78 results
Search Results
2. A Descriptive Systematic Review of Food Insecurity and Intimate Partner Violence in Southern Africa.
- Author
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Macassa, Gloria, Francisco, Jose da Cruz, Militao, Elias, and Soares, Joaquim
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INTIMATE partner violence ,ONLINE information services ,FOOD security ,SYSTEMATIC reviews ,CRIMINALS ,RISK assessment ,MEDLINE ,CLIMATE change - Abstract
Food insecurity and intimate partner violence are important determinants of health and wellbeing in southern Africa. However, very little research has attempted to investigate the association between them even though food insecurity is anticipated to increase in the region, mostly owing to climate change. The objective of this paper was to descriptively review peer reviewed studies that investigated the relationship between food insecurity and intimate partner violence in southern Africa. Literature searches were carried out in Scopus, Web of Science and PubMed databases without any time restriction. A total of five studies that investigated the association between food insecurity and intimate partner violence were identified in South Africa and Swaziland. Of these four studies used a cross-sectional design, and one employed a longitudinal design. Samples varied from 406 to 2479 individuals. No empirical studies were found for the remaining southern African countries of Angola, Botswana, Malawi, Namibia, Zambia, Zimbabwe, Lesotho, and Mozambique. Moreover, the reported findings indicated that there was an association between food insecurity and interpersonal violence (i.e., physical, psychological, and emotional) in the sub-region regardless the fact that the five studies used diverse measurements of both food insecurity and intimate partner violence. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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3. Gender and conservation agriculture in East and Southern Africa: towards a research agenda.
- Author
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Farnworth, Cathy Rozel, Baudron, Frédéric, Andersson, Jens A., Misiko, Michael, Badstue, Lone, and Stirling, Clare M.
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CLIMATE change ,CROP management ,CROP residues ,DECISION making - Abstract
It is remarkable that despite wide-ranging, in-depth studies over many years, almost no conservation agriculture (CA) studies consider gender and gender relations as a potential explanatory factor for (low) adoption rates. This is important because CA demands new ways of working with the farm system. Implementation will inevitably involve a reallocation of men's and women's resources as well as having an impact upon their ability to realize their gender interests. With respect to intra-household decision-making and the distribution of benefits, CA interventions have implications for labour requirements and labour allocation, investment decisions with respect to mechanization and herbicide use, crop choice, and residue management. CA practice may impact upon the ability of households to source a wide variety of crops, wild plants, and insects and small animals for household nutrition. Gender biases in extension service design can sideline women. This paper examines the limited research to date on the interactions between CA interventions and gender in East and Southern Africa, and, based on the gaps observed, sets out a research agenda. It argues that attention to gender in CA is particularly timely given the increasing interest in CA as a means of adapting to climate change. [ABSTRACT FROM PUBLISHER]
- Published
- 2016
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4. Late Quaternary research in southern Africa: progress, challenges and future trajectories.
- Author
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Fitchett, Jennifer M., Grab, Stefan W., Bamford, Marion K., and Mackay, Anson W.
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QUATERNARY paleoecology ,PALEOENVIRONMENTAL studies ,CLIMATE change ,INTRODUCED organisms & the environment ,ANTHROPOGENIC effects on nature ,ECOLOGY - Abstract
Southern African late Quaternary research has developed rapidly during recent decades, with an increase in the range of proxies used, the inclusion of new field sites, and increased international collaboration and skills transfer. This has enabled recent meta-studies into the synoptic drivers of palaeoenvironmental shifts across the region, and of spatial variability in climatic and environmental changes. Expanded research has also highlighted uncertainties in the understanding of southern African palaeoenvironments, and the relationships with Northern Hemisphere analogues, encouraging on-going critical debate within the discipline. Given current concerns of climate change impacts on the natural environment, the spread of invasives, increased fire frequency, and anthropogenic influences on the natural environment, palaeoenvironmental data and inferences are increasingly being utilised outside of the palaeoenvironmental discipline, providing a valuable inter-disciplinary platform for global change science in the region. Relative to the size, landscape and climatic heterogeneity and resultant biome variability across southern Africa, the network of palaeoenvironmental study sites remains sparse, and arguably insufficient to resolve key debates. This paper critically reviews these spatial gaps in palaeoenvironmental knowledge, with a particular emphasis on the shortfalls of the current network of study sites and palaeoenvironmental records in resolving debates concerning latitudinal shifts of the Westerlies, conditions during the last glacial maximum and contemporaneous Northern and Southern Hemisphere climatic events. Southern African applications of palaeoenvironmental science in exploring ecological trait shifts, fire influences and anthropogenic impacts are briefly discussed, to facilitate the future identification of key sites, proxies, debates and applications in ongoing regional Quaternary work. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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5. Climate change impacts on agricultural trade and food security in emerging economies: case of Southern Africa.
- Author
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Sabola, Gift Andrew
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CLIMATE change ,FOOD security ,AGRICULTURAL industries ,GLOBAL temperature changes - Abstract
Climate change has been a significant threat to sustainable agriculture impacting trade and food security. This research investigates the impacts of climate change on agricultural trade and food security in emerging economies focusing on Southern Africa. The research employed the dynamic panel Generalised Method of Moments (GMM) using panel data for the period 2012 to 2021 obtained from a sample of 12 Southern African countries selected based on data availability. The main independent variables to the research were climate change variables (temperature and precipitation). Other control variables included were population growth, food inflation and agricultural growth. The study found significant negative effects of climate change on agriculture trade. Whilst temperature changes were found to have insignificant effects, precipitation changes were found to have significant positive effects. The research recommends concerted efforts towards climate change adaptation and mitigation for sustainable agriculture. Based on the Findings, sustainable food security and agricultural trade Southern African emerging economies may be attained through effective climate change mitigation and adaptation approaches particularly promoting climate-smart agriculture (CSA). [ABSTRACT FROM AUTHOR]
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- 2024
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6. Linking poverty, HIV/AIDS and climate change to human and ecosystem vulnerability in southern Africa: consequences for livelihoods and sustainable ecosystem management.
- Author
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Shackleton, Sheona E. and Shackleton, Charlie M.
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CLIMATE change ,BIOTIC communities ,ECOSYSTEM management ,POVERTY ,AIDS - Abstract
People in southern Africa are facing escalating levels of risk, uncertainty and consequently vulnerability as a result of multiple interacting stressors, including HIV/AIDS, poverty, food insecurity, weak governance, climate change and land degradation, to name but a few. Vulnerability or livelihood insecurity emerges when poor people as individuals or social units have to face harmful threats or shocks with inadequate capacity to respond effectively. In such situations, people often have no choice but to turn to their immediate environment for support. Evidence suggests that rising levels of human vulnerability are driving increased dependency on biodiversity and ecosystem services, which in turn, and along with other threats, is rendering ecosystems more vulnerable. This paper explores the dynamic and complex linkages and feedbacks between human vulnerability and ecosystem vulnerability, drawing on data from the southern African region. Human vulnerability is conceptualized as a threat to ecosystem health, as driven by the interplay between a number of current and emerging factors. We focus on poverty, HIV/AIDS and more intense climate extremes as examples of stressors on livelihoods and direct and indirect drivers of ecosystem change. We discuss how some of the responses to increased vulnerability may pose threats to biodiversity conservation, ecosystem management and sustainable development, whilst considering potential solutions that rely on a thorough understanding of coupled social–ecological systems and the interplay between multiple stressors and responses at different scales. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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7. Drought regimes in Southern Africa and how well GCMs simulate them.
- Author
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Ujeneza, Eva and Abiodun, Babatunde
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DROUGHTS ,CLIMATE change ,SPATIOTEMPORAL processes ,SIMULATION methods & models ,PRINCIPAL components analysis - Abstract
This paper presents the spatial and temporal structures of drought regimes in Southern Africa and evaluates the capability of ten global climate models (GCMs) in simulating the regimes. The study uses a multi-scaled standardized index (called standardized precipitation evapo-transpiration index, SPEI) in characterizing droughts over Southern Africa at 3- and 12-month scales. The spatial patterns of the drought regimes are identified using the rotated principal component analysis (PCA) on the SPEI, while the temporal characteristics of the drought regimes are studied using wavelet analysis. The relationship between each drought regime and global SSTs (and climate indices) is quantified using correlation analysis and wavelet coherence analysis. The study also quantifies the capability of the GCMs in simulating the drought regimes. The PCA results show four main drought regimes that jointly explain about 50 % SPEI variance over South Africa. The drought regimes (hereafter PF1, PF2, PF3 and PF4) centre over the south-western part of Southern Africa (i.e. South Africa, Botswana and Namibia common border), Zimbabwe, Tanzania, and Angola, respectively. PF1, PF2 and PF4 are strongly correlated with SST over the South Atlantic, Tropical Pacific and Indian Oceans, while PF3 is strongly correlated with the SST over the Tropical Pacific, Atlantic and Indian Oceans. The drought regimes (except PF4) have significant coherence with some atmospheric teleconnection, but the strength, duration, and phase of the coherence vary with time. All the GCMs simulate the drought regimes better at a 3-month scale than at a 12-month scale. At a 3-month scale, 70 % of the GCMs simulate all the drought regimes with a high correlation coefficient (r > 0.6), but at a 12-month scale only 60 % of the models simulate at least three of the drought regimes with a high correlation coefficient (r > 0.6). The results of this study have applications in using GCMs to study the underlying atmospheric dynamics that control droughts and to understand the impacts of global warming on droughts. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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8. Advancing climate compatible development: lessons from southern Africa.
- Author
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Stringer, Lindsay, Dougill, Andrew, Dyer, Jen, Vincent, Katharine, Fritzsche, Florian, Leventon, Julia, Falcão, Mario, Manyakaidze, Pascal, Syampungani, Stephen, Powell, Philip, and Kalaba, Gabriel
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CLIMATE change ,BIOLOGICAL adaptation ,ECONOMIC development ,FORESTS & forestry ,AGRICULTURE - Abstract
Climate compatible development (CCD) has emerged as a new concept that bridges climate change adaptation, mitigation and community-based development. Progress towards CCD requires multi-stakeholder, multi-sector working and the development of partnerships between actors who may not otherwise have worked together. This creates challenges and opportunities that require careful examination at project and institutional levels and necessitates the sharing of experiences between different settings. In this paper, we draw on the outcomes from a multi-stakeholder workshop held in Mozambique in 2012, the final in a series of activities in a regional project assessing emerging CCD partnerships across southern Africa. The workshop involved policymakers, researchers and representatives from NGOs and the private sector. We employ a content analysis of workshop notes and presentations to identify the progress and challenges in moving four case study countries (the Democratic Republic of the Congo, Mozambique, Zambia and Zimbabwe) towards CCD pathways, by exploring experiences from both project and policy levels. To advance institutional support for the development of successful CCD policies, practices and partnerships, we conclude that there is a need for: (a) institutional development at the national level to strengthen coordination and more clearly define roles and responsibilities across sectors, based on the identification of capacity and knowledge gaps; (b) partnership development, drawing on key strengths and competences of different stakeholders and emphasising the roles of the private sector and traditional authorities; (c) learning and knowledge-sharing through national and regional fora; and (d) development of mechanisms that permit more equitable and transparent distribution of costs and benefits. These factors can facilitate development of multi-stakeholder, multi-level partnerships that are grounded in community engagement from the outset, helping to translate CCD policy statements into on-the-ground action. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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9. Rainfall-derived growing season characteristics for agricultural impact assessments in South Africa.
- Author
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Ambrosino, Chiara, Chandler, Richard, and Todd, Martin
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METEOROLOGICAL precipitation ,ENVIRONMENTAL impact analysis ,SUBSISTENCE farming ,CLIMATE change ,RAINFALL anomalies ,PRECIPITATION anomalies ,AGRICULTURE ,AGRICULTURAL climatology - Abstract
Precipitation variability imposes significant pressure in areas where agricultural practice is dominated by smallholder farmers who are dependent on subsistence farming. Advances in the understanding of this variability, in both time and space, have an important role to play in increasing the resilience of agricultural systems. The need is particularly pressing in regions of the world such as the African continent, which is already affected by multiple stresses including poverty and economic and political instability. In this paper, we explore the use of generalised linear models (GLMs) for this purpose, via a case study from north-east South Africa. A GLM is used to link the local rainfall variability to large-scale climate drivers identified from previous subcontinental-scale analyses, and the ability of the resulting model to simulate precipitation features that are relevant in agricultural applications is evaluated. We focus in particular on a set of growing season indices, proposed for the investigation of intraseasonal characteristics relevant for maize production in the region. Seven indices were computed from spatially averaged daily rainfall series from nine stations in the study area. As a first attempt to use GLMs for this type of application, the results are encouraging and suggest that the models are able to reproduce a range of agriculture-relevant indices. However, further research into spatial correlation structure is recommended to improve the multisite generation of the rainfall-derived characteristics. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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10. Lightning as a geomorphic agent on mountain summits: Evidence from southern Africa.
- Author
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Knight, Jasper and Grab, Stefan W.
- Subjects
- *
GEOMORPHIC cycle , *MOUNTAINS , *GEOMORPHOLOGY , *CLIMATE change - Abstract
Abstract: The presence of angular bedrock-derived debris on mountain summits worldwide has usually been associated with present or past periglacial frost shattering, thermal fracturing and other climatically-mediated weathering processes. Climatic inferences are commonly made based on such geomorphological evidence, even if frost shattering and other processes are unlikely under present climatic conditions. This paper questions this assumed genetic link between present/past climate and production of angular bedrock-derived debris by describing the geomorphological impacts of lightning strikes on exposed mountain summits. Using examples from the high Drakensberg of eastern Lesotho, southern Africa, the impacts of lightning strikes are described, which include the generation of angular, fractured bedrock-derived debris. These impacts are identified in the field based on clear and unambiguous criteria that can be used to distinguish between lightning-induced weathering processes and those processes associated with ‘more typical’ alpine weathering. This paper argues that lightning strikes are an important geomorphic agent of, in particular, low-latitude mountain summits, and that to make uncritical climatic inferences based on the presence of ‘frost shattered debris’ on mountain summits is wholly erroneous. [Copyright &y& Elsevier]
- Published
- 2014
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11. A simple regional coupled model experiment for summer-time climate simulation over southern Africa.
- Author
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Ratnam, J., Behera, S., Masumoto, Y., Takahashi, K., and Yamagata, T.
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SUMMER ,CLIMATE change ,ATMOSPHERIC models ,METEOROLOGICAL precipitation ,WIND shear ,OCEAN temperature ,SIMULATION methods & models - Abstract
The main aim of this paper is to evaluate the Advanced Research Weather Research and Forecasting (WRF) regional model in simulating the precipitation over southern Africa during austral summer. The model's ability to reproduce the southern African mean climate and its variability around this mean state was evaluated by using the two-tier approach of specifying sea surface temperature (SST) to WRF and by using the one-tier approach of coupling the WRF with a simple mixed-layer ocean model. The boundary conditions provided by the reanalysis-II data were used for the simulations. Model experiments were conducted for twelve austral summers from DJF1998-99 to DJF2009-10. The experiments using both the two-tier and one-tier approaches simulated the spatial and temporal distributions of the precipitation realistically. However, both experiments simulated negative biases over Mozambique. Furthermore, analysis of the wet and dry spells revealed that the one-tier approach is superior to the two-tier approach. Based on the analysis of the surface temperature and the zonal wind shear it is noted that the simple mixed-layer ocean model coupled to WRF can be effectively used in place of two-tier WRF to simulate the climate of southern Africa. This is an important result because specification of SST at higher temporal resolutions in the subtropics is the most difficult task in the two-tier approach for most regional prediction models. The one-tier approach with the simple mixed-layer model can effectively reduce the complicacy of finding good SST predictions. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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12. Climate Change Impacts on Water Availability and Use in the Limpopo River Basin.
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Zhu, Tingju and Ringler, Claudia
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WATER supply management ,CLIMATE change ,WATER use ,WATER consumption ,IRRIGATION - Abstract
This paper analyzes the effects of climate change on water availability and use in the Limpopo River Basin of Southern Africa, using a linked modeling system consisting of a semi-distributed global hydrological model and the Water Simulation Module (WSM) of the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT). Although the WSM simulates all major water use sectors, the focus of this study is to evaluate the implications of climate change on irrigation water supply in the catchments of the Limpopo River Basin within the four riparian countries: Botswana, Mozambique, South Africa, and Zimbabwe. The analysis found that water resources of the Limpopo River Basin are already stressed under today's climate conditions. Projected water infrastructure and management interventions are expected to improve the situation by 2050 if current climate conditions continue into the future. However, under the climate change scenarios studied here, water supply availability is expected to worsen considerably by 2050. Assessing hydrological impacts of climate change is crucial given that expansion of irrigated areas has been postulated as a key adaptation strategy for Sub-Saharan Africa. Such expansion will need to take into account future changes in water availability in African river basins. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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13. The relationship of ungulate δ13C and environment in the temperate biome of southern Africa, and its palaeoclimatic application.
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Luyt, Julie, Hare, Vincent J., and Sealy, Judith
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- *
BIOMES , *ECOSYSTEM services , *CLIMATE change , *MOISTURE - Abstract
Abstract The relationship between ungulate stable carbon isotope values and environmental variables (temperature, relative humidity, precipitation) remains poorly understood. In this paper, we evaluate this relationship for, predominantly, C 3 ecosystems in the winter rainfall areas of southern Africa. In our dataset (290 individuals representing 23 species), δ13C values of ungulate enamel are significantly correlated with mean annual precipitation (MAP), moisture index (MI) and summer aridity index (SAI), variables that also influence the distribution of C 3 /C 4 grasses. Our study confirms previous findings that faunal δ13C values in C 3 ecosystems are most strongly correlated with variables related to precipitation. δ13C enamel values for ungulate browsers are more strongly correlated with a larger number of environmental variables than values for grazers and mixed feeders and vary according to vegetation type. We apply regressions derived from the modern dataset to estimate palaeoclimatic shifts based on δ13C enamel values of browsing fauna at the Pleistocene sites of Hoedjiespunt and Elandsfontein in South Africa. Highlights • Ungulate δ13C correlates best with seasonality of rainfall index SAI, as well as MAP and a moisture index. • Browser δ13C values are correlated with (among others) MAP and MAPE. • Meteorological correlates of δ13C ensembles reveal palaeoenvironments. • Correction for palaeo-pCO 2 has a significant impact on the interpretation of fossil δ13C. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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14. 'Carry on sampling!'- assessing marine fish biodiversity and discovery rates in southern Africa.
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Von Der Heyden, Sophie
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MARINE fishes ,BIODIVERSITY ,ENDEMIC animals ,FISH speciation ,FISH surveys ,CLIMATE change ,MAXIMUM likelihood statistics - Abstract
Biodiversity inventories are not yet complete, with potentially thousands of species unknown to science. This paper aims to (1) elucidate the historical discovery rate of endemic southern African marine fishes and (2) to estimate the number of potentially undescribed endemic marine fishes in the region using a statistical model and which factors (e.g. size/depth) contribute to unknown diversity. Thirdly, all species described globally for eight families (Blennidae, Clinidae, Gobiidae, Lutjanidae, Rajidae, Sciaenidae, Scyliorhinidae, Sparidae) were analysed to elucidate unknown diversity in these groups. The oceans of southern Africa, including Namibia, South Africa and Mozambique, encompassing sections of the south-eastern Atlantic Ocean and the western Indian Ocean. Literature surveys from a number of sources were carried out to compile lists of species descriptions from 1758 onwards. Species-accumulation curves were plotted for all endemic species, as well as for different components of size and depth. A maximum likelihood model was used to estimate the number of undescribed endemic marine fishes in southern Africa, as well as for all other categories, including global families. Fish discovery rates in southern Africa have varied with time. Estimates suggest that at least 25% of the total endemic fish fauna remain unknown and that size is the greatest predictor of whether a fish has been described. Smaller-sized fishes and those inhabiting shallow areas are most likely to be undersampled. It is likely that most undescribed fishes inhabit the subtropical/tropical waters of the east coast. At the current rate of fish description, it will take at least 50 years to describe the total endemic fish fauna. However, estimates of unknown species are probably higher because of cryptic species within currently recognized taxa. Climate change may also contribute to range expansions of marine species, further complicating the status of endemicity in southern African marine fishes. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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15. Rainfall variability and trends in semi-arid Botswana: Implications for climate change adaptation policy
- Author
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Batisani, Nnyaladzi and Yarnal, Brent
- Subjects
- *
RAINFALL , *ACCLIMATIZATION , *ARID regions , *GOVERNMENT policy on climate change , *AGRICULTURAL scientists - Abstract
Abstract: Rainfall variability is an important feature of semi-arid climates, and climate change is likely to increase that variability in many of these regions. An understanding of rainfall variability and trends in that variability is needed to help vulnerable dryland agriculturalists and policymakers address current climate variation and future climate change. The goals of this paper are to examine this climatic phenomenon in semi-arid Botswana, to investigate these results for signs of climate change, and to explore the policy implications for climate adaptation. To reach these goals, the paper determines rainfall variability and monthly and annual trends in that variability. The results agree with earlier work showing gradients in rainfall and rainfall variability across Botswana. The results also identify a trend towards decreased rainfall throughout the nation, which is associated with decreases in the number of rainy days. Both the drying trend and decrease in rainy days agree with climate change projections for southern Africa. The paper discusses policies that the government could adopt to help its farmers adapt to climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
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16. Adaptation to climate change in Southern Africa: factoring in AIDS.
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Drimie, Scott and Gillespie, Stuart
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CLIMATE change ,AIDS ,FOOD security ,LITERATURE reviews ,BIOLOGICAL adaptation ,CIVIL society ,FOOD deserts - Abstract
Abstract: This paper addresses the interactions between the AIDS epidemic and climate change in southern Africa, particularly as they impact on food security. An assessment was undertaken through a comprehensive literature review. Understanding the underlying causes of regional food insecurity inevitably means understanding the role of the AIDS epidemic and increasingly climate change amongst other stressors. AIDS cuts through household and community level capacity, as well as the capacity of key facilitators of the adaptation process including state extension services and civil society organisations. The main argument of the paper is that adaptation to climate change must explicitly factor in the existing and long-term effects of the epidemic. While calls for embracing adaptation abound, little is being done to assess and strengthen the organisational capacity of institutions, which should play leading roles in any attempt to help prepare for a changing climate. In particular the capacity of key agencies has been undermined by the AIDS epidemic. This reiterates the need for a multisectoral approach and building bridges between agriculture and health sectors to ensure longer term support to livelihoods where HIV and hunger coexist, often overlaid by climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
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17. Climate variability and change over southern Africa: impacts and challenges.
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Sithole, Alec and Murewi, Cyril T. F.
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CLIMATOLOGY ,RAINFALL ,VEGETATION & climate ,ENVIRONMENTAL degradation ,BIODIVERSITY - Abstract
In this paper, the influence of climate variability and change on the environment was studied over southern Africa using ground-based and remotely sensed data. A time series analysis of rainfall and temperature anomalies indicated that there was a high rainfall and temperature variability in the region. The influence of global teleconnections on rainfall patterns over southern Africa showed that in some areas there was a spatial variation in their strength, increasing from west to east. Maps of NDVI, from 1982 to 2004, showed that changes in vegetation cover were more apparent during the dry season than during the wet season. The study also revealed that climate variability and change are linked to decreasing rainfall and hence, decreasing regional water resources and biodiversity and increasing environmental degradation. With the regional population expected increase, this depletion of resources poses the greatest regional environmental challenge to humankind. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
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18. Global Change and Southern Africa.
- Author
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Meadows, Michael E.
- Subjects
CLIMATE change ,BIODIVERSITY ,AGRICULTURE ,WATER supply ,AGRICULTURAL policy - Abstract
The developing nations of southern Africa have previously been identified as vulnerable to the vagaries of global change, particularly in terms of future climate change. This paper explores recent climate change scenarios for the region in terms of some representative sectors of the environment-society interface, namely biodiversity, agriculture and related land uses, water resources and health issues. It is concluded that the impacts of predicted climate changes over the next century are likely to be very marked indeed. Biome distribution, agriculture, rangelands and water resources are highlighted as being negatively impacted in ways that will increase the vulnerability of the great majority of the region's population to natural hazards. The potential impact of these changes on the prolific biodiversity of southern Africa is clear. Holistic policy responses, incorporating both environmental and human development concerns, are required in the near future if a crisis is to be averted. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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19. How do sectoral policies support climate compatible development? An empirical analysis focusing on southern Africa.
- Author
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England, Matthew I., Stringer, Lindsay C., Dougill, Andrew J., and Afionis, Stavros
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GOVERNMENT policy on climate change ,PARIS Agreement (2016) ,ENVIRONMENTAL policy ,GREENHOUSE gas mitigation ,FEDERAL government - Abstract
Promoting inclusive and sustainable economic and social development whilst simultaneously adapting to climate change impacts and mitigating greenhouse gas emissions – Climate Compatible Development (CCD) – requires coherent policy approaches that span multiple sectors. This paper develops and applies a qualitative content analysis to assess national sector policies of ten southern African countries to determine their approaches for water, agriculture, forestry and energy and their compatibility with the aims of the three dimensions of CCD (development, climate adaptation and climate mitigation). Results indicate that sector policies currently only partially support shifts towards CCD, with approaches that both complement and detract from CCD being prioritized by national governments. Agriculture offers the greatest number of potentially viable approaches capable of achieving the development, adaptation and mitigation aims inherent in CCD, while energy the least. National governments should focus on developing coherent, cross-sector approaches that deliver such potential triple wins in order to promote new forms of inclusive and sustainable economic and social development, whilst facilitating adaptation to climate change impacts and supporting mitigation activities. Doing so will also go a long way towards ensuring the progress needed for achieving the Sustainable Development Goals (SDGs) and Nationally Determined Contributions (NDCs) to the Paris Climate Agreement. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
20. Evaluating manual conservation agriculture systems in southern Africa.
- Author
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Thierfelder, Christian, Matemba-Mutasa, Rumbidzai, Bunderson, W. Trent, Mutenje, Munyaradzi, Nyagumbo, Isaiah, and Mupangwa, Walter
- Subjects
- *
AGRICULTURAL conservation , *SEED treatment , *SOWING , *AGRICULTURAL ecology , *CLIMATE change , *CROPPING systems - Abstract
Future threats of climate variability and change and accelerated soil degradation in southern Africa have increased the need for more sustainable and “climate-smart” agriculture practices. Manual systems of conservation agriculture (CA) based on seeding into planting basins or direct seeding techniques have received increased attention over the last decade. However, a critical review of the pros and cons of the different manual seeding systems under different agro-ecologies has been lacking. This paper aims at analysing different manual seeding systems in areas extending from central Mozambique to central Malawi. Results show that CA systems perform differently in contrasting agro-ecological environments. Direct seeded treatments had greater maize yields than conventional tillage practices by an average of 12–27% and outperformed the conventional practice in nine out of fourteen yield comparisons. Basin planted treatments performed well only in Sofala and Manica (15%) with yield penalties of −9% in Tete. The strongest factor influencing maize grain yields in the more variable areas of Manica and Sofala was the quality of season and the location, whereas tillage treatment and location were more important in the higher rainfall areas of Tete. Direct seeding systems out-yielded other treatments in areas of higher rainfall and responded better to a favourable environment than conventional tillage practices. CA systems, especially direct seeding in Malawi, Manica and Sofala, showed greater financial returns to investments and labour productivity due to reduced labour costs and higher yields. Labour savings of up to 43 labour days ha −1 could be achieved with direct seeded treatments in Malawi. The results of this research clearly highlight the need for site-specific recommendations and adaptation of CA systems to different agro-ecological environments. Blanket recommendations of one CA system across many agro-ecologies, as has often been done in the past, will only lead to underperformance of CA in some areas and rejection by smallholder farmers if yield benefits are not achieved. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
21. The impact of the Agulhas Current System on precipitation in southern Africa in regional climate simulations covering the recent past and future.
- Author
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Tim, Nele, Zorita, Eduardo, Hünicke, Birgit, and Ivanciu, Ioana
- Subjects
AGULHAS Current ,METEOROLOGICAL precipitation ,CLIMATOLOGY ,CLIMATE change - Abstract
Southern African climate is strongly impacted by climate change. Precipitation is a key variable in this region as it is linked to agriculture and water supply. An analysis of simulations with a regional atmospheric model over the last decades and the 21st century shows that in the past precipitation has decreased in some coastal areas of South Africa and increased in the rest of southern Africa. However, it is projected to decrease over the whole southern part of the domain in the future. The Agulhas Current System, including the current and the leakage, surrounds the continent in the east and south and it is found to impact precipitation. The reduction in the strength of the Agulhas Current is linked to a reduction in precipitation along the southeast coast. The Agulhas leakage, the part of the Agulhas Current that leaves the system and flows into the South Atlantic, impacts the precipitation in the southwest of the continent, located in the winter rainfall zone. A more intense Agulhas leakage is linked to a reduction in precipitation in this region. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
22. Rock hyrax middens: A palaeoenvironmental archive for southern African drylands
- Author
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Chase, Brian M., Scott, Louis, Meadows, Michael E., Gil-Romera, Graciela, Boom, Arnoud, Carr, Andrew S., Reimer, Paula J., Truc, Loïc, Valsecchi, Verushka, and Quick, Lynne J.
- Subjects
- *
ROCK hyrax , *CLIMATE change , *OCEAN circulation , *RAINFALL , *WETLANDS , *ARID regions - Abstract
Abstract: Like many of the world''s subtropical regions, southern Africa is highly sensitive to changes in the earth''s climate system, but a dearth of reliable palaeoenvironmental records means that relatively little is known about how regional environments have been affected over centennial to multi-millennial timescales. To a large extent this sensitivity is a function of the position of these regions at the interface between temperate and tropical circulation systems. The resulting seasonality and irregularity of rainfall have limited the development of suitable archives, such as lakes and wetlands, for the preservation of palaeoenvironmental proxies. This paper reviews and evaluates the value of rock hyrax middens as novel palaeoenvironmental archives in southern Africa. Considered are (1) the contemporary taxonomy, distribution and ecology of hyraxes, (2) the mechanisms of hyrax midden development, their physical and chemical structure, rates of accumulation and age; and (3) the palaeoenvironmental proxies preserved within hyrax middens, including fossil pollen, stable isotopes and biomarkers. The interpretive constraints and opportunities offered by these various midden characteristics are assessed with a view to demonstrating the potential of these deposits, widespread as they are through arid and semi-arid southern Africa, in providing a more detailed and chronologically resolved view of late Quaternary palaeoenvironments across the subcontinent. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
23. Rainfall variability and vegetation dynamics of the lower Limpopo Valley, Southern Africa, 500AD to present
- Author
-
Ekblom, Anneli, Gillson, Lindsey, Risberg, Jan, Holmgren, Karin, and Chidoub, Zara
- Subjects
- *
RAINFALL , *VEGETATION dynamics , *RIPARIAN ecology , *HYDROLOGY , *SAVANNA ecology , *PALEOECOLOGY - Abstract
Abstract: The long‐term responses of vegetation to climate variability are of relevance for predicting present and future vegetation change, and have implications for the management of savanna and riparian ecosystems. This paper explores the links between regional rainfall, hydrology and vegetation dynamics in the savannas and riverine forests of the lower Limpopo Valley, southern Africa, from 800AD to the present, reviewing palaeoecological data (fossil pollen, spores, diatoms and lithology) from several hydrological systems in Kruger National Park (KNP), South Africa and Limpopo National Park (PNL), Mozambique. The PNL–KNP records show that riverine arboreal taxa expanded during wetter periods, including 800–1400AD and after 1800AD. Between 1400 and 1800AD, grasses, savanna taxa and generalist taxa were favored over riparian taxa, a change that is linked with the onset of dry spells in the region (corresponding to the so-called Little Ice Age). The most extreme drought events around 1700AD resulted in a marked decline of riparian forest taxa near Lake Mapimbi, KNP. In contrast, many water-scarce sequences away from the riverine environment, such as Radio Pan, Mafayeni Pan, Malahlapanga Pan and Lake Makwadzi show stable grassland vegetation throughout the last 1200years. The results demonstrate the resilience of the grassland–savanna ecosystems to projected climate change with warmer and overall drier climate. The riverine forests are predicted to be more vulnerable especially as more extreme weather events are projected. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
24. Using Principal Component Analysis for information-rich socio-ecological vulnerability mapping in Southern Africa
- Author
-
Abson, David J., Dougill, Andrew J., and Stringer, Lindsay C.
- Subjects
- *
PRINCIPAL components analysis , *SOCIAL ecology , *PSYCHOLOGICAL vulnerability , *ECOLOGICAL mapping , *CLIMATE change , *INVESTORS , *DATA analysis - Abstract
Abstract: Aggregate measures that capture multiple aspects of socio-ecological vulnerability in a single or small number of vulnerability indices can produce vulnerability maps that act as powerful visual tools to identify those areas most susceptible to future environmental changes. Such indices are easily communicable and offer valuable guidance to policymakers and investors, providing insights as to where more targeted research or policy interventions can address current challenges and reduce future risks. However, such aggregation inevitably reduces the richness of information provided by the suites of individual vulnerability indicators on which the maps are based. This trade-off between information richness and information communicability is a challenge in the quantification and communication of complex phenomena such as socio-ecological vulnerability. This paper investigates the use of Principal Component Analysis (PCA) techniques as a means of creating information-rich spatially-explicit aggregate indices of socio-ecological vulnerability. We present a ‘proof of concept’ analysis of socio-ecological vulnerability for the Southern Africa Development Community (SADC) region using both PCA and traditional normalization based techniques for generating spatially explicit, aggregated socio-ecological vulnerability indices. The vulnerability indices are based on published biophysical and socio-economic data and mapped at a 10 arc minute resolution. The resulting PCA based vulnerability maps indicate the regional spatial variability of four statistically independent, unique components of socio-ecological vulnerability, providing more information than the single index produced using a normalization/summation approach. Such uncorrelated, information-rich vulnerability indices represent a potentially useful policy tool for identifying areas of greatest concern in terms of both the relative level, and the underlying causes and impacts of, socio-ecological vulnerability to environmental changes across broad spatial scales. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
25. Assessing the sustainability of energy technological systems in Southern Africa: A review and way forward.
- Author
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Musango, Josephine K. and Brent, Alan C.
- Subjects
TECHNOLOGICAL innovations ,ENERGY security ,CLIMATE change ,ENERGY policy ,RENEWABLE energy sources ,DECISION making - Abstract
Abstract: The field of technology assessment is not new, but it continues to be relevant today more than ever, especially in the energy sector. Issues related to climate change, energy security and sustainability in general are at the core of all energy policies and strategies. The development of new and more sustainable energy technologies are needed to address these challenges. As part of this, energy technology assessment tools can help decision-makers with the identification of sustainable energy solutions, in order to integrate them in long-term energy policies and strategies. The concept and practice of sustainable development has subsequently manifested in the technology assessment field. This implies the re-classification of technology assessment into ecological, economic and social (and other) goals. In the Southern African context, specifically, there is no formal and coherent approach to energy technology assessment from a sustainability perspective. Governments in the region are finding it challenging to establish national policies concerning energy technology assessment. Indeed, the review reveals the limited use of the term “technology assessment” in energy evaluation studies in Southern Africa. Energy sustainability assessments may be reported, but certainly not from the perspectives of the technology management community, and, although a number of studies have discussed the issues of sustainability in technology assessment, none account for technology sustainability assessment from a holistic perspective. The paper argues that it is in this area that further research is needed. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
26. “A sky of brass and burning winds”: documentary evidence of rainfall variability in the Kingdom of Lesotho, Southern Africa, 1824–1900.
- Author
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Nash, David J. and Grab, Stefan W.
- Subjects
- *
WEATHER forecasting , *RAINFALL , *CLIMATE change , *DROUGHTS , *TEMPERATURE effect - Abstract
Forecasting austral summer rainfall in southern Africa is hampered by a lack of long-term instrumental data. This paper extends the historical record for the subcontinent by presenting the first extensive 19th century climate history for Lesotho derived from documentary evidence. The data sources included unpublished English-, French- and Sesotho-language materials archived in Lesotho, South Africa and the UK. These included letters, journals and reports written by missionaries and colonial authorities, which were supplemented by newspapers, diaries, travelogues and other historical sources. Each source was read in chronological order, with any climate information recorded verbatim. Observations were classified into five categories (Very Wet, Relatively Wet, ‘Normal’, Relatively Dry, and Very Dry) based upon the predominant documented climate during each ‘rain-year’ (July to June). The latter portion of the chronology was then compared for accuracy against available instrumental precipitation records from Maseru (1886–1900). The results yield a semi-continuous record of climate information from 1824 to 1900. Data are restricted to lowland areas, but reveal drought episodes in 1833–34, 1841–42, 1845–47, 1848–51, 1858–63, 1865–69, 1876–80, 1882–85 and 1895–99 (the most severe drought years being 1850–51 and 1862–63) and wet periods or floods in 1835–36, 1838–41, 1847–48, 1854–56, 1863–65, 1873–75, 1880–81, 1885–86 and 1890–94. The rainfall chronology is compared with similar records for South Africa, Botswana and Zimbabwe. Linkages to possible forcing mechanisms, including ENSO teleconnections and historical coral-derived southwest Indian Ocean sea surface temperature variations are also explored. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
27. Evaluating Successful Livelihood Adaptation to Climate Variability and Change in Southern Africa.
- Author
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Osbahr, Henny, Twyman, Chasca, Adger, W. Neil, and Thomas, David S. G.
- Subjects
- *
AGRICULTURE , *CLIMATE change , *ECOLOGICAL resilience , *RURAL development - Abstract
This paper examines the success of small-scale farming livelihoods in adapting to climate variability and change. We represent adaptation actions as choices within a response space that includes coping but also longer-term adaptation actions, and define success as those actions which promote system resilience, promote legitimate institutional change, and hence generate and sustain collective action. We explore data on social responses from four regions across South Africa and Mozambique facing a variety of climate risks. The analysis suggests that some collective adaptation actions enhance livelihood resilience to climate change and variability but others have negative spillover effects to other scales. Any assessment of successful adaptation is, however, constrained by the scale of analysis in terms of the temporal and spatial boundaries on the system being investigated. In addition, the diversity of mechanisms by which rural communities in southern Africa adapt to risks suggests that external interventions to assist adaptation will need to be sensitive to the location-specific nature of adaptation. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
28. Adaptations to climate change, drought and desertification: local insights to enhance policy in southern Africa.
- Author
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Stringer, Lindsay C., Dyer, Jen C., Reed, Mark S., Dougill, Andrew J., Twyman, Chasca, and Mkwambisi, David
- Subjects
CLIMATE change ,DESERTIFICATION ,DROUGHTS ,NATURAL resources ,SOCIOECONOMICS ,ENVIRONMENTAL engineering ,BIOLOGICAL adaptation - Abstract
Abstract: The impacts of climate change, drought and desertification are closely interlinked, and most acutely experienced by populations whose livelihoods depend principally on natural resources. Given the increases in extreme weather events projected to affect the Southern Africa region, it is essential to assess how household and community-level adaptations have been helped or hindered by institutional structures and national policy instruments. In particular, there is a need to reflect on efforts related to the United Nations’ environmental conventions to ensure that policies support the maintenance of local adaptations and help retain the resilience of socio-economic and environmental systems. This paper examines three interlinked drivers of adaptation: climate change, desertification and drought, assessing the extent to which international and national policy supports local adaptive strategies in three countries in southern Africa. We show that while common ground exists between desertification and climate change adaptations at the policy level, they are insufficiently mainstreamed within broader development approaches. Similarly, there are some overlaps between policy-driven and autonomous local adaptations, but the mutually supportive links between them are poorly developed. Further efforts to integrate local adaptation strategies within policy could increase local resilience to environmental change, while also contributing to wider development goals. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
29. Last Glacial Maximum dune activity in the Kalahari Desert of southern Africa: observations and simulations
- Author
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Chase, Brian M. and Brewer, Simon
- Subjects
- *
SAND dunes , *GLACIERS , *CLIMATE change , *SIMULATION methods & models , *WEATHER - Abstract
Abstract: It has long been understood that as ephemeral landscape features sand dunes are highly sensitive to environmental change, and thus their distribution and the timing of their development may provide clues to past climate dynamics. The relationship between climate and dune activity, however, is neither simple nor straightforward, with a range of controls affecting the balance between erodibility (the availability of sediment for deflation) and erosivity (the potential for sediment transport). To explore such complex systems over large spatial and temporal scales, a number of dune activity indices (DAI) have been created that incorporate wind speed and moisture balances to calculate the potential for, and degree of dune mobilisation. Using modern weather station data, these indices have generally been shown to provide reasonable indications of dune activity potential. Until recently, however, the detailed quantitative data required to inform these equations has not been available for past climate scenarios, and attempts to determine the relative importance of the various controls of dune activity have relied on rough estimations of climatic parameters. This paper combines data from monthly general circulation model (GCM) outputs from the coupled Ocean-Atmosphere GCMs for 21ka with the most detailed DAI equation presently available to calculate the potential for dune reactivation in southern Africa during the Last Glacial Maximum (LGM, 18–24ka). Based on these data and calculations it is indicated that there was significantly less potential for dune activity across southern Africa at 21ka. When compared to the aeolian sediment records from the region, this study poses serious and fundamental questions about: 1) the reliability of the model outputs, 2) the degree to which DAIs are able to account for the complexity and dynamics of aeolian systems, and/or 3) the interpretation of dune records as palaeoclimatic proxies at millennial time scales. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
30. The climate of Namaqualand in the nineteenth century.
- Author
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Kelso, Clare and Vogel, Coleen
- Subjects
- *
CLIMATE change ,HISTORY of Southern Africa - Abstract
Southern African climatic change research is hampered by a lack of long-term historical data sets. This paper aims to extend the historical climate record for southern Africa to the semi-arid area of Namaqualand in the Northern Cape province of South Africa. This is achieved through extensive archival research, making use of historical documentary sources such as missionary journals and letters, traveller's writings and government reports and letters. References to precipitation and other climatic conditions have been extracted and categorised, providing a proxy precipitation data set for Namaqualand for the nineteenth century. Notwithstanding problems of data accuracy and interpretation the reconstruction enables the detection of severe and extreme periods. Measured meteorological data, available from the late 1870s, was compared to the data set derived from documentary sources in order to ascertain the accuracy of the data set and monthly rainfall data has been used to identify seasonal anomalies. Confidence ratings on derived dry and wet periods, where appropriate, have been assigned to each year. The study extends the geographical area of existing research and extracts the major periods of drought and climatic stress, from the growing body of historical climate research. The most widespread drought periods affecting the southern and eastern Cape, Namaqualand and the Kalahari were 1820-1821; 1825-1827; 1834; 1861-1862; 1874-1875; 1880-1883 and 1894-1896. Finally, a possible correspondence is suggested between some of the widespread droughts and the El Nino Southern Oscillation (ENSO). [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
31. Lightning as a geomorphic agent: Reply to comments by Sumner.
- Author
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Knight, Jasper and Grab, Stefan W.
- Subjects
- *
GEOMORPHOLOGY , *LIGHTNING , *CLIMATE change , *LANDFORMS , *MOUNTAINS - Abstract
Abstract: Sumner's comments are mainly concerned with the climatic interpretation of angular boulders and associated landforms. This goes beyond the aims and scope of our paper (Knight and Grab, 2014), which are to examine the role of lightning as a geomorphic agent on mountain summits. We critically address three issues raised by Sumner: (1) that we have misinterpreted the literature that we cited in our paper; (2) that the role of lightning during the last glacial maximum can be evaluated; and (3) that studies of processes, geomorphology and palaeoclimate in the Drakensberg, southern Africa, do not make use of circular reasoning. We reiterate that lightning strikes are a significant geomorphic agent in generating angular debris on low-latitude mountain summits, and therefore to make uncritical climatic inferences based on the presence of ‘frost shattered debris’ is erroneous and should be avoided. [Copyright &y& Elsevier]
- Published
- 2014
- Full Text
- View/download PDF
32. A network to understand the changing socio‐ecology of the southern African woodlands (SEOSAW): Challenges, benefits, and methods.
- Subjects
FORESTS & forestry ,TROPICAL dry forests ,CLIMATE change ,SUSTAINABILITY - Abstract
Societal Impact Statement: The sustainable management of the southern African woodlands is closely linked to the livelihoods of over 150 M people. Findings from the Socio‐Ecological Observatory for the Southern African Woodlands (SEOSAW) will underpin the sustainability of two of the largest industries on the continent: woodfuels and timber. SEOSAW will also improve our understanding of how human use shapes the biogeography and functioning of these ecosystems. Summary: Here we describe a new network of researchers and long‐term, in situ, measurements that will characterize the changing socio‐ecology of the woodlands of southern Africa. These woodlands encompass the largest savanna in the world, but are chronically understudied, with few long‐term measurements.A network of permanent sample plots (PSPs) is required to: (a) address management issues, particularly related to sustainable harvesting for energy and timber; (b) understand how the woodlands are responding to a range of global and local drivers, such as climate change, CO2 fertilization, and harvesting; and (c) answer basic questions about biogeography, ecosystem function, and the role humans play in shaping the ecology of the region.We draw on other successful networks of PSPs and adapt their methods to the specific challenges of working in southern African woodlands. In particular we suggest divergences from established forest monitoring protocols that are needed to (a) adapt to a high level of ecosystem structural diversity (from open savanna to dry forest); (b) quantify the chronic disturbances by people, fire, and herbivores; (c) quantify the diversity and function of the understory of grasses, forbs, and shrubs; (d) understand the life histories of resprouting trees; and (e) conduct work in highly utilized, human‐dominated landscapes.We conclude by discussing how the SEOSAW network will integrate with remote sensing and modeling approaches. Throughout, we highlight the challenges inherent to integrating work by forest and savanna ecologists, and the wide range of skills needed to fully understand the socio‐ecology of the southern African woodlands. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
33. Ecocriticism and Youth Climate Heroes in Southern Africa: Centering Global South Perspectives and Activism in Isaura.
- Author
-
Schreiber, Katja
- Subjects
ECOCRITICISM ,ACTIVISM ,SUSTAINABILITY ,CLIMATE change - Published
- 2021
- Full Text
- View/download PDF
34. Using a coupled dynamic factor – random forest analysis (DFRFA) to reveal drivers of spatiotemporal heterogeneity in the semi-arid regions of southern Africa.
- Author
-
Southworth, Jane, Bunting, Erin, Zhu, Likai, Ryan, Sadie J., Herrero, Hannah V., Waylen, Peter, Muñoz-Carpena, Rafael, Campo-Bescós, Miguel A., and Kaplan, David
- Subjects
ARID regions climate ,RANDOM forest algorithms ,CLIMATE change ,SOCIOECONOMIC factors - Abstract
Understanding the drivers of large-scale vegetation change is critical to managing landscapes and key to predicting how projected climate and land use changes will affect regional vegetation patterns. This study aimed to improve our understanding of the role, magnitude, and spatial distribution of the key environmental and socioeconomic factors driving vegetation change in a southern African savanna. This research was conducted across the Kwando, Okavango and Zambezi catchments of southern Africa (Angola, Namibia, Botswana and Zambia) and explored vegetation cover change across the region from 2001–2010. A novel coupled analysis was applied to model the dynamic biophysical factors then to determine the discrete / social drivers of spatial heterogeneity on vegetation. Previous research applied Dynamic Factor Analysis (DFA), a multivariate times series dimension reduction technique, to ten years of monthly remotely sensed vegetation data (MODIS-derived normalized difference vegetation index, NDVI), and a suite of time-series (monthly) environmental covariates: precipitation, mean, minimum and maximum air temperature, soil moisture, relative humidity, fire and potential evapotranspiration. This initial research was performed at a regional scale to develop meso-scale models explaining mean regional NDVI patterns. The regional DFA predictions were compared to the fine-scale MODIS time series using Kendall’s Tau and Sen’s Slope to identify pixels where the DFA model we had developed, under or over predicted NDVI. Once identified, a Random Forest (RF) analysis using a series of static social and physical variables was applied to explain these remaining areas of under- and over- prediction to fully explore the drivers of heterogeneity in this savanna system. The RF analysis revealed the importance of protected areas, elevation, soil type, locations of higher population, roads, and settlements, in explaining fine scale differences in vegetation biomass. While the previously applied DFA generated a model of environmental variables driving NDVI, the RF work developed here highlighted human influences dominating that signal. The combined DFRFA model approach explains almost 90% of the variance in NDVI across this landscape from 2001–2010. Our methodology presents a unique coupling of dynamic and static factor analyses, yielding novel insights into savanna heterogeneity, and providing a tool of great potential for researchers and managers alike. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
35. Impact of Climate Change on Precipitation in Zambeze River Basin in Southern Africa.
- Author
-
Banze, Felix, Jiali Guo, and Shi Xiaotao
- Subjects
METEOROLOGICAL precipitation ,CLIMATE change ,WATER supply -- Climatic factors - Abstract
The Intergovernmental Panel on Climate Change (IPCC) concluded that there is a consensus that the increase in atmospheric greenhouse gases will result in climate change, which will cause the sea level to rise, increase frequency of extreme climatic events such as intense storms, heavy rainfall events and droughts. This will increase the frequency of climate-related hazards, causing loss of life, social disruption and economic hardships. There is less consensus on the magnitude of change of climatic variables, nonetheless several studies have shown that climate change will have an impact on the availability and demand for water resources. Southern Africa lies in one of the regions of the world that is most susceptible to climate variability and change. In southern Africa, climate change is likely to affect nearly every aspect of human well-being, from agricultural productivity and energy use to flood control, municipal and industrial water supply as well as wildlife management, since the region is characterized by highly spatial and temporally variable rainfall, and in some cases, scarce water resources. This study presents the future change projection in precipitation under RCP2.6, RCP4.5 and RCP8.5 scenarios of the CanESM2 outputs using the Statistical Downscaling Model (SDSM) for 50 stations in Zambeze River basin during the two future periods: near future (2031-2060) and far future (2071-2100). For assessment of climate change, the baseline period (1979-2013) was partitioned into two periods for SDSM calibration (1979-1996) and validation (1997-2013). The results show that SDSM was not a very robust method for the simulation of precipitation for this study area, the model could not replicate observed precipitation very well. This is due to its conditional nature and high variability in space. The results also showed that there is a decrease in monthly precipitation during wet period (October-March) and an increase during the dry period (April-September). The upward monthly increase in projected precipitation expected is in August (300%, 325%) with RCP4.5 and maximum decrease in March (38%) with RCP4.5 for all scenarios for NF and FF respectively, and the projected annual precipitation is expected to decrease with time for all scenarios. It was observed that the maximum decrease will range from 7-21.8% for near future (NF) and 2-21% for far future (FF). [ABSTRACT FROM AUTHOR]
- Published
- 2018
36. Beyond the nature-labour divide: trade union responses to climate change in South Africa.
- Author
-
Räthzel, Nora, Cock, Jacklyn, and Uzzell, David
- Subjects
ENVIRONMENTAL policy ,ENVIRONMENTAL degradation ,LABOR unions ,LABOR movement ,CLIMATE change - Abstract
We present the life histories of two environmentally engaged unionists in South Africa, who were decisive for formulating the environmental programmes of their respective trade unions. Their experiences of participating in the resistance against apartheid in universities and factories taught them the necessity to connect different struggles and equipped them with the knowledge and ability to connect the fight for workers’ rights with the fight against environmental degradation. Both activists experienced the difficulty of integrating ‘the environment’ politically and practically into a trade union agenda. The labour movement has traditionally experienced nature as a place outside of work to be enjoyed for recreation. While nature constitutes an indispensable condition for labour, it has been privately appropriated by Capital. For environmental policies to form an integral part of union agendas, nature needs to be wrestled away from its appropriation by Capital and understood as an inseparable ally of labour. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
37. Austral summer Southern Africa precipitation extremes forced by the El Niño-Southern oscillation and the subtropical Indian Ocean dipole.
- Author
-
Hoell, Andrew and Cheng, Linyin
- Subjects
METEOROLOGICAL precipitation ,EL Nino ,CLIMATE change ,ANTICYCLONES ,ECOLOGY - Abstract
Southern Africa, defined here as the African continent south of 15°S latitude, is prone to seasonal precipitation extremes during December-March that have profound effects on large populations of people. The intensity of summertime precipitation extremes can be remarkable, with wet seasons experiencing up to a doubling of the seasonal average precipitation. Recognizing the importance of understanding the causes of Southern Africa precipitation extremes for the purpose of improved early warning, an 80-member ensemble of atmospheric model simulations forced by observed time-varying boundary conditions during 1979-2016 is used to examine the mechanisms by which December-March precipitation extremes are delivered to Southern Africa and whether the El Niño-Southern Oscillation (ENSO) and the Subtropical Indian Ocean Dipole (SIOD) modify the probabilities of extreme seasonal precipitation occurrences. The model simulations reveal that the synchronous ENSO and SIOD phasing conditions the probability of December-March extreme precipitation occurrences. The probability of extreme wet seasons is greatly increased by La Niña, especially so when combined with a positive SIOD, and greatly decreased by El Niño regardless of SIOD phasing. By contrast, the probability of extreme dry seasons is increased by El Niño and is decreased by La Niña. The mechanisms by which extreme precipitation are delivered are the same regardless of ENSO and SIOD phase. Extreme wet seasons are a result of an anomalous lower tropospheric cyclone over Southern Africa that increases convergence and moisture fluxes into the region while extreme dry seasons are a result of an anomalous lower tropospheric anticyclone that decreases convergence and moisture fluxes into the region. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
38. Climate change, urban settlements and quality of life: The case of the Southern African Development Community region.
- Author
-
Mupedziswa, Rodreck and Kubanga, Kefentse Princess
- Subjects
DEFORESTATION ,FLOODS ,CLIMATE change ,QUALITY of life - Abstract
Climate change has become a major national, regional and international problem cutting across developed and developing countries alike. Within the developing world, the effects of climate change have been devastating; this has caused enormous human suffering. The Southern African Development Community (SADC), a regional economic block of 15 countries, has been badly ravaged by the vagaries of climate change. The urban areas in particular appear to have been very badly impacted as flooding, drought, pollution and deforestation have become endemic. The impacts of climate change have triggered human suffering of immense magnitude, especially in areas occupied by the marginalised. This article is based on desk research and, using qualitative analysis, examines the impact of climate change on SADC countries, considers initiatives that the regional block has in place in efforts to mitigate the human suffering experienced as a consequence of the negative impact of climate change and, finally, considers a way forward. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
- Full Text
- View/download PDF
39. Smallholder Farmers' Perceptions on Climate Change and the Use of Sustainable Agricultural Practices in the Chinyanja Triangle, Southern Africa.
- Author
-
Makate, Clifton, Makate, Marshall, and Mango, Nelson
- Subjects
CLIMATE change ,SUSTAINABLE agriculture ,AGRICULTURAL policy ,ECOLOGICAL resilience - Abstract
In developing regions with high levels of poverty and a dependence on climate sensitive agriculture, studies focusing on climate change adaptation, planning, and policy processes, have gained relative importance over the years. This study assesses the impact of farmer perceptions regarding climate change on the use of sustainable agricultural practices as an adaptation strategy in the Chinyanja Triangle, Southern Africa. In this empirical approach, we adopt methods that account for the plausibility that unmeasured characteristics exist, which are correlated with perceptions and the adoption of Sustainable Agricultural Practices. We use a unique and representative dataset collected in December 2012 and June 2013, from smallholder farmers in the Chinyanja Triangle. The results indicate that farmer's perceptions significantly influence the use of sustainable agricultural practices. Specifically, we established that farmer perceptions considerably impact the use of grain legume rotations, inorganic fertilizers, compost, and farmyard manure. Our results highlight the need for a serious and perhaps equal consideration of farmer perceptions regarding climate change, as important inputs to climate change adaptation policies targeted at enhancing climatic resilience in smallholder farming communities. This is plausible as the adaptation and pliability of farmers to the effects of climate change should be a social process involving the collective efforts from various stakeholders. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
40. Pigeonpea breeding in eastern and southern Africa: challenges and opportunities.
- Author
-
Kaoneka, Seleman R., Saxena, Rachit K., Silim, Said N., Odeny, Damaris A., Ganga Rao, Nadigatla Veera Prabha Rama, Shimelis, Hussein A., Siambi, Moses, Varshney, Rajeev K., and Léon, J.
- Subjects
PLANT breeding ,FOOD security ,PLANT germplasm ,AGROFORESTRY ,PIGEON pea - Abstract
Pigeonpea ( Cajanus cajan [ L.] Millspaugh) is an important multipurpose grain legume crop primarily grown in tropical and subtropical areas of Asia, Africa and Latin America. In Africa, the crop is grown for several purposes including food security, income generation, livestock feed and in agroforestry. Production in Eastern and Southern Africa ( ESA) is however faced with many challenges including limited use of high-yielding cultivars, diseases and pests, drought, under-investment in research and lack of scientific expertise. The aim of this review is to highlight the challenges facing pigeonpea breeding research in ESA and the existing opportunities for improving the overall pigeonpea subsector in the region. We discuss the potential of the recently available pigeonpea genomic resources for accelerated molecular breeding, the prospects for conventional breeding and commercial hybrid pigeonpea, and the relevant seed policies, among others, which are viewed as opportunities to enhance pigeonpea productivity. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
41. Review of the projected impacts of climate change on coastal fishes in southern Africa.
- Author
-
Potts, W., Götz, A., and James, N.
- Subjects
CLIMATE change ,FISHERIES ,MICROCOSM & macrocosm ,HABITATS - Abstract
The coastal zone represents one of the most economically and ecologically important ecosystems on the planet, none more so than in southern Africa. This manuscript examines the potential impacts of climate change on the coastal fishes in southern Africa and provides some of the first information for the Southern Hemisphere, outside of Australasia. It begins by describing the coastal zone in terms of its physical characteristics, climate, fish biodiversity and fisheries. The region is divided into seven biogeographical zones based on previous descriptions and interpretations by the authors. A global review of the impacts of climate change on coastal zones is then applied to make qualitative predictions on the likely impacts of climate change on migratory, resident, estuarine-dependent and catadromous fishes in each of these biogeographical zones. In many respects the southern African region represents a microcosm of climate change variability and of coastal habitats. Based on the broad range of climate change impacts and life history styles of coastal fishes, the predicted impacts on fishes will be diverse. If anything, this review reveals our lack of fundamental knowledge in this field, in particular in southern Africa. Several research priorities, including the need for process-based fundamental research programs are highlighted. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
42. Southern Africa winter temperature shifts and their link to the Southern Annular Mode.
- Author
-
Manatsa, Desmond, Matarira, Caxton, Mushore, Terrence, and Mudavanhu, Chipo
- Subjects
ATMOSPHERIC temperature ,ANTARCTIC oscillation ,MODES of variability (Climatology) ,ORTHOGONAL functions ,CLIMATE change - Abstract
The main characteristics of spatial and temporal variability of the winter (June-August) observed surface air minimum temperature (SAMT) of southern Africa (Africa south of the equator) were examined from 1960 to 2011. The empirical orthogonal function (EOF) analysis was used to extract the dominant mode of SAMT variability. Statistically significant shifts were detected in both the index derived from the spatially averaged regional SAMT and its EOF1 time coefficients. These discontinuities displayed a sharp rise followed by an abrupt drop during the periods around 1988 and 2007 respectively. The years corresponded to change points in the Southern Annular Mode index where the 1988 significant alteration to a relatively more positive index polarity was followed by a sudden weakening during the latter shift. The development of the warm phase coincided with the decoupling of SAM from SAMT. This occurred when the strengthening of the western ridge of the Mascarene High appeared to be coupled to the creation of anomalously low pressure systems over Angola and the region pole-ward of South Africa. In this epoch, the meridional wind over southern Africa reversed to become predominantly northerly and hence was symptomatic of warm temperature advection from the lower latitudes. However the post 2007 era, though still of indeterminate length, is characterized by a partial return to the pre-1988 circulation conditions. This implies that the impacts of SAM's epochal alterations have implications not only for the current climate, but also for the interpretation of climate change over southern Africa. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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43. Considering the impact of climate change on human communities significantly alters the outcome of species and site-based vulnerability assessments.
- Author
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Segan, Daniel B., Hole, David G., Donatti, Camila I., Zganjar, Chris, Martin, Shaun, Butchart, Stuart H. M., Watson, James E. M., and Richardson, David
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EFFECT of human beings on climate change ,BIODIVERSITY ,ENVIRONMENTAL impact analysis ,SPECIES distribution - Abstract
Aim Human activities are largely responsible for the processes that threaten biodiversity, yet potential changes in human behaviour as a response to climate change are ignored in most species and site-based vulnerability assessments (VAs). Here we assess how incorporation of the potential impact of climate change on humans alters our view of vulnerability when using well-established site and species VA methodologies. Location Southern Africa. Methods Our baseline was two published studies that used accepted VA methodologies aimed at examining the direct impacts of climate changes on species and sites. The first identified potential shifts in the distributions of 164 restricted-range avian species, the second forecasted species turnover in 331 Important Bird and Biodiversity Areas (IBAs). We used a published spatially explicit assessment of potential climate change impacts on people to evaluate which species and sites overlap with human populations most likely to be impacted. By doing this, we were able to assess how the integration of potential climate impacts on human populations changes our perception of which species and sites are most vulnerable to climate change. Results We found no correlation between species and sites most likely to be impacted directly by climate change and those where the potential response of human populations could drive major indirect impacts. The relative vulnerability of individual species and sites shifted when potential impacts of climate change on human communities were considered, with more than one-fifth of species and one-tenth of sites moving from 'low' to 'high' risk. Main conclusions Standard VA methodologies that fail to consider how people are likely to respond to climate change will result in systematically biased assessments. This may lead to the implementation of inappropriate management actions, and a failure to address those species or sites that may be uniquely, or additionally, imperilled by the impacts of human responses to climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
44. Last Glacial Maximum conditions in southern Africa: Are we any closer to understanding the climate of this time period?
- Author
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Stone, Abi E.C.
- Subjects
GLACIAL climates ,CLIMATE change ,PALEOENVIRONMENTAL studies ,COMPUTER simulation - Abstract
The Last Glacial Maximum (LGM) (21±2 ka) is an important period for which to understand past climatic and environmental conditions. In particular it is a key time-slice for evaluating the performance of numerical climate model simulations of glacial palaeoclimates using palaeoenvironmental data sets. However, our palaeoenvironmental data sets and reconstructions of climatic conditions at the LGM are still debated in certain regions. This is the case for southern Africa, despite more than half a century of research since early conceptual models of palaeoclimate were proposed. The greatest debates are about the spatial patterning of relatively wetter and drier conditions than present and the position of the mid-latitude westerlies at the LGM. Different patterns emerge from: separate syntheses of palaeoenvironmental proxies, from different numerical model simulations and from comparisons of the two. In this review of the progress over half a century of research in southern Africa: (1) a brief historical review of key conceptual models is given, (2) key points of conflict that emerge in synthesis of palaeoenvironmental proxy records are outlined and (3) numerical model simulations are considered. From these, some points for future progress are suggested. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
45. Climate Variability and Societal Dynamics in Pre-Colonial Southern African History (AD 900-1840): A Synthesis and Critique.
- Author
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HANNAFORD, MATTHEW J., BIGG, GRANT R., JONES, JULIE M., PHIMISTER, IAN, and STAUB, MARTIAL
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CLIMATE & civilization ,CLIMATE change ,PALEOCLIMATOLOGY ,RAINFALL ,AGRICULTURE ,GREAT Zimbabwe (Extinct city) ,MAPUNGUBWE Site (South Africa) ,HISTORY ,ECOLOGY - Abstract
The role of climate variability in pre-colonial southern African history is highly disputed. We here provide a synthesis and critique of climate-society discourses relating to two regionally-defining periods of state formation and disaggregation. The first period involves the eleventh-thirteenth century development of socio-political complexity and the rise of southern Africa's first state, Mapungubwe, followed by its collapse and the shift in regional power to Great Zimbabwe. The later period encompasses the early-nineteenth century difaqane/mfecane mass migrations, violence and ensuing state-building activity. To further our assessment, we consider the wider contentious issues of climate causation and determinism in a regional context, but dispute suggestions of paradigm shift towards simplistic environmental collapse. Nevertheless, we specifically point to ambiguities in palaeoclimate records, a narrative tendency toward monocausal explanations and a lack of integration among the literature as reasons for a sustained divergence in interpretation regarding the significance of climate. We move on to discuss the potential of integrative approaches to illuminate understanding of the complex interactions between past climate variability and human activity. In order to do so, we highlight interlinked concepts such as vulnerability and resilience as key for bridging the gap between the natural and social sciences. To conclude, we point to future climate-society priorities and ways forward in the form of research areas, data prospects and questions. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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46. The bi-decadal rainfall cycle, Southern Annular Mode and tropical cyclones over the Limpopo River Basin, southern Africa.
- Author
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Malherbe, Johan, Landman, Willem, and Engelbrecht, Francois
- Subjects
RAINFALL ,CLIMATE change ,TROPICAL cyclones ,OCEAN circulation - Abstract
The association between bi-decadal rainfall variability over southern Africa and the rainfall contributed by tropical cyclonic systems from the Southwest Indian Ocean (SWIO) provides a potential means towards understanding decadal-scale variability over parts of the region. A multi-decadal period is considered, focusing on the anomalous tropospheric patterns that induced a particularly wet 8-year long sub-period over the Limpopo River Basin. The wet sub-period was also characterized by a larger contribution to rainfall by tropical cyclones and depressions. The findings suggest that a broadening of the Hadley circulation underpinned by an anomalous anticyclonic pattern to the east of southern Africa altered tropospheric steering flow, relative vorticity and moisture contents spatially during the sub-period of 8 years. These circulation modulations induced enhanced potential for tropical systems from the SWIO to cause precipitation over the Limpopo River Basin. The same patterns are also conducive to increasing rainfall over the larger subcontinent, therefore explaining the positive association in the bi-decadal rainfall cycle and rainfall contributed by tropical cyclonic systems from the SWIO. An overview of regional circulation anomlies during alternating near-decadal wet and dry epochs is given. The regional circulation anomalies are also explained in hemispheric context, specifically in relation to the Southern Annular Mode, towards understanding variation over other parts of the Southern Hemisphere at this time scale. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
47. Dynamical seasonal prediction of Southern African summer precipitation.
- Author
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Yuan, Chaoxia, Tozuka, Tomoki, Landman, Willem, and Yamagata, Toshio
- Subjects
LONG-range weather forecasting ,STATISTICAL correlation ,CLIMATE change ,METEOROLOGICAL precipitation ,SUMMER ,EL Nino - Abstract
Prediction skill for southern African (16°-33°E, 22°-35°S) summer precipitation in the Scale Interaction Experiment-Frontier coupled model is assessed for the period of 1982-2008. Using three different observation datasets, deterministic forecasts are evaluated by anomaly correlation coefficients, whereas scores of relative operating characteristic and relative operating level are used to evaluate probabilistic forecasts. We have found that these scores for December-February precipitation forecasts initialized on October 1st are significant at 95 % confidence level. On a local scale, the level of prediction skill in the northwestern and central parts of southern Africa is higher than that in northeastern South Africa. El Niño/Southern Oscillation (ENSO) provides the major source of predictability, but the relationship with ENSO is too strong in the model. The Benguela Niño, the basin mode in the tropical Indian Ocean, the subtropical dipole modes in the South Atlantic and the southern Indian Oceans and ENSO Modoki may provide additional sources of predictability. Within the wet season from October to the following April, the precipitation anomalies in December-February are the most predictable. This study presents promising results for seasonal prediction of precipitation anomaly in the extratropics, where seasonal prediction has been considered a difficult task. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
48. Correlates of hyperdiversity in southern African ice plants ( Aizoaceae).
- Author
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Valente, Luis M., Britton, Adam W., Powell, Martyn P., Papadopulos, Alexander S. T., Burgoyne, Priscilla M., and Savolainen, Vincent
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ICE plant ,PLANT phylogeny ,CLIMATE change ,PLANT diversity ,PLANT morphology - Abstract
The exceptionally high plant diversity of the Greater Cape Floristic Region ( GCFR) comprises a combination of ancient lineages and young radiations. A previous phylogenetic study of Aizoaceae subfamily Ruschioideae dated the radiation of this clade of > 1500 species in the GCFR to 3.8-8.7 Mya, establishing it as a flagship example of a diversification event triggered by the onset of a summer-arid climate in the region. However, a more recent analysis found an older age for the Ruschioideae lineage (17 Mya), suggesting that the group may in fact have originated much before the aridification of the region 10-15 Mya. Here, we reassess the tempo of radiation of ice plants by using the most complete generic-level phylogenetic tree for Aizoaceae to date, a revised calibration age and a new dating method. Our estimates of the age of the clade are even younger than initially thought (stem age 1.13-6.49 Mya), supporting the hypothesis that the radiation post-dates the establishment of an arid environment in the GCFR and firmly placing the radiation among the fastest in angiosperms (diversification rate of 4.4 species per million years). We also statistically examine environmental and morphological correlates of richness in ice plants and find that diversity is strongly linked with precipitation, temperature, topographic complexity and the evolution of highly succulent leaves and wide-band tracheids. © 2013 The Authors. Botanical Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174, 110-129. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
49. Agroclimatological suitability mapping for dryland maize production in Lesotho.
- Author
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Moeletsi, Mokhele and Walker, Sue
- Subjects
AGRICULTURAL meteorology ,ARID regions agriculture ,CORN ,PROBABILITY theory ,CLIMATE change - Abstract
The climatic potential of maize under dryland farming in Lesotho, southern Africa, was investigated using five suitability indices comprising probability of accumulating heat units of greater than 1,500 growing degree days, probability of a frost-free growing season, probability of seasonal rainfall of more than 500 mm, probability of drought during the flowering to grain-filling stages and the slope of an area. A geographic information system layer was prepared for each of these parameters and the layers overlaid using different weights for each of the climatic suitability indices to obtain an agroclimatic maize suitability map for Lesotho. This analysis yielded different suitability classes. This variability points to prevalence of climatic constraints that need to be acknowledged when attempting to identify management strategies that can optimize the rain-fed maize production in climatically variable environments. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
50. Cloud bands over southern Africa: seasonality, contribution to rainfall variability and modulation by the MJO.
- Author
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Hart, Neil, Reason, Chris, and Fauchereau, Nicolas
- Subjects
ATMOSPHERIC troughs ,CLOUDS ,RAINFALL ,CLIMATE change ,SEASONS - Abstract
Tropical-extratropical cloud band systems over southern Africa, known as tropical temperate troughs (TTTs), are known to contribute substantially to South African summer rainfall. This study performs a comprehensive assessment of the seasonal cycle and rainfall contribution of TTTs by using a novel object-based strategy that explicitly tracks these systems for their full life cycle. The methodology incorporates a simple assignment of station rainfall data to each event, thereby creating a database containing detailed rainfall characteristics for each TTT. This is used to explore the importance of TTTs for rain days and climatological rainfall totals in October-March. Average contributions range from 30 to 60 % with substantial spatial heterogeneity observed. TTT rainfall contributions over the Highveld and eastern escarpment are lower than expected. A short analysis of TTT rainfall variability indicates TTTs provide substantial, but not dominant, intraseasonal and interannual variability in station rainfall totals. TTTs are however responsible for a high proportion of heavy rainfall days. Of 52 extreme rainfall events in the 1979-1999 period, 30 are associated with these tropical-extratropical interactions. Cut-off lows were included in the evolution of 6 of these TTTs. The study concludes with an analysis of the question: does the Madden-Julian Oscillation influence the intensity of TTT rainfall over South Africa? Results suggest a weak but significant suppression (enhancement) of intensity during phase 1(6). [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
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