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Environmental factors, particularly climate conditions, play a crucial role in influencing the growth and yield of cultivated crops. Although knowledge on their influence has been revealed in many records, our understanding of their relationship in West Papua is limited due to lack of data. This research leveraged data of monthly climate variables (temperature, rainfall, and radiation intensity) and crop yields from West Papua, Indonesia for period 2011-2020. The Analysis revealed varying trends in the highest average monthly air temperature, humidity, rainfall, and radiation intensity across different months. Despite these fluctuations, there was a general tendency towards increased harvested area and rice, maize, and soybeans production. While the overall impact of climate variables on crop productivity appeared insignificant, certain nuances emerge. Specifically, air humidity demonstrated a notable influence on rice productivity, while air temperature has a stronger effect on maize productivity than other climate variables. However, correlation tests indicated that the relationship between climate variables (air temperature, humidity, rainfall, and radiation intensity) and crop productivity, particularly maize, rice, and soybeans, did not reach statistical significance. This underscores the complexity of the interplay between climate dynamics and agricultural outcomes. [ABSTRACT FROM AUTHOR]

This paper explores what the San Diego region may look like in the year 2050 as projected changes in regional climate conditions take place. Focusing on interrelated issues of climate change, sea level rise, population growth, land use, and changes in water, energy, public health, wildfires, biodiversity, and habitat, the paper reviews the potential impacts of a changing climate by 2050 and makes recommendations for changes in planning processes at the local and regional levels to prepare for these impacts. The original research for this study was completed in 2008 by a team of 40 experts from the region including universities, nonprofit organizations, local governments, public sector agencies and private sector entities. This paper has now been updated with more recent research regarding climate change adaptation while preserving the integrity of the original research team's work. The simulated impacts discussed in this study are based on regional projections of climate change generated by scientists at Scripps Institution of Oceanography, employing three climate models and two emissions scenarios used by the Intergovernmental Panel on Climate Change. The impacts are discussed in the context of significant regional growth expected during the period as well as an aging population base. Key issues explored in the report include potential inundation of six selected low-lying coastal areas in San Diego due to sea level rise, potential shortfalls in water deliveries, peak energy demand increases due to higher temperatures, growing risk of devastating wildfires, migrations of species in response to higher temperatures in an increasingly fragmented natural habitat, and public health issues associated with extreme temperature events. [ABSTRACT FROM AUTHOR]

Greater economic growth could lead to greater greenhouse gas emissions, while simultaneously enhancing various aspects of human well-being and the capacity to adapt to climate change. This begs the question as to whether and, if so, for how long would a richer-but-warmer world be better for well-being than poorer-butcooler worlds. To shed light on this issue, this paper draws upon results of the ‘Fast Track’ assessment (FTA) reported in a special issue of Global Environmental Change: Part A 14 (1): 1-99 (2004), which employed the IPCC's emissions scenarios to project future climate change and its global impacts on various determinants of human and environmental well-being. Results suggest that notwithstanding climate change, through much of this century, human well-being is likely to be highest in the richest-but-warmest (A1FI) world and lower in poorerbut-cooler worlds. With respect to environmental well-being, matters may be best under the A1FI world for some critical environmental indicators through 2085-2100, but not necessarily for others. An alternative analysis using the Stern Review's worst-case results for potential welfare losses due to climate change indicates that welfare, adjusted for market and non-market impacts of climate change and the risk of catastrophe, should be highest under the A1FI scenario, at least through 2100. [ABSTRACT FROM AUTHOR]

This paper describes the development, testing and validation of a simple steady-state hygrothermal bed model (BED) which predicts conditions of temperature and relative humidity within the bed core (the occupied space between mattress and covering), given the temperature and relative humidity of the bedroom. BED is the second of three simple steady-state models that in combination allow the impact of modifying bedroom hygrothermal conditions on dust mite populations to be assessed. The first of the trio is Condensation Targeter II, an existing validated model that predicts average monthly conditions of temperature and relative humidity within the bedroom. These conditions are then used as boundary conditions for the BED model which predicts hygrothermal conditions within the bed core. Finally, these outputs are in turn used as inputs to a simple Mite Population Index (MPI) model (to be described elsewhere) that predicts their likely effect on house dust mite population growth in the bed. As reported here, BED has been validated using monitored bedroom and bed data for a full year in three dwellings and the results show that the steady state model predicts monthly bed hygrothermal conditions with a reasonable degree of accuracy. Using Condensation Targeter II and BED in combination, a sensitivity study has been carried out to assess the impact of changes in input parameters of both models on hygrothermal conditions in the bed core. This highlights the importance that the design of the fabric and services of the building has on the hygrothermal conditions in a bed. The impact of climate change has also been assessed using future climate change scenarios. Practical application: This paper describes in detail a simple steady-state model, (BED) which is used to predict the monthly average temperature and relative humidity within a bed, given the ambient conditions within the bedroon. The input parameters, output parameters and the model formulae are provided so that the model can be easily implemented. BED is the second of three simple models that are used to predict, first the bedroon conditions (Condensation Targeter II), second the bed conditions (BED) and finally the likely effect on house dust mite population growth using a simple Mite Population Index (MPI). The Condensation Targeter II and MPI models are described in detail elsewhere. The suite of models allows the testing of the impact of dwelling design and occupant use on likely mite population growth and therefore the health risks of the occupants. It also allows the impact of climate change to be analysed. [ABSTRACT FROM AUTHOR]

This paper quantifies the vulnerability of and risk to water resources (VRWR) under a scenario of climate change in the arid and semi-arid region of West China. A new approach integrating hazard, sensitivity, resilience, exposure and risk is developed to assess the VRWR from climate change. Drought is regarded as the key hazard, with its frequency and severity defined using a surface humidity index. Exposure is quantitatively linked with indicators of population and social and economic characteristics using statistical and Geographical Information System (GIS) methodologies. Risk is defined as the product of hazard, exposure and vulnerability, while vulnerability is treated as a function of sensitivity and adaptation. Vulnerability and risk in the water resources system in the coming 20 years are assessed for the RCP 4.5 scenario. The results reveal that both hazard and exposure of water resources display strong spatial variation in the study area. High hazard and exposure are found in the northern Tianshan Mountain as well as the eastern part of Hexi Corridor. Water resources are particularly sensitive to variation in precipitation and potential evapotranspiration in the upstream areas of Hexi Corridor, rivers in Central Asia, headwater streams of Tarim River and most of Chang Tang Plateau. Our assessment shows that there is high vulnerability of and risk to water resources in the study area, especially in the areas of Hexi Corridor, northern Tianshan Mountain and Tarim River. Under the RCP 4.5 climate change scenario, the vulnerability and risk decline over the entire area but remain at a serious level in inland rivers in Hexi Corridor, northern Tianshan Mountain and headwater streams of Tarim River. Thus, these areas are the highest priority for strengthening policy measures to adapt to climate change and reduce exposure and vulnerability and their risk to water resources. [ABSTRACT FROM AUTHOR]

The Thornthwaite Moisture Index (TMI) is a climate classification used in biophysical and biological studies. A TMI mapping of Victoria/Australia over the century indicated its applicability to assess climate change induced patterns of moisture variability. This paper progresses upon this, developing analytical procedures to assess the quality of the climate data used as input, and to select suitable spatial resolution for the output map. It is argued here that these are interrelated issues, and that the selection of a certain data quality level or a spatial resolution for TMI mapping needs to consider a trade-off between precision and scale. Results indicated that different trade-off options affect the climate classification and, therefore, a proposed framework can be used for non-arbitrary decisions on TMI mapping. [ABSTRACT FROM PUBLISHER]

Climatic zoning is an essential element of most building energy efficiency programs, however there is no widely accepted scientific technique for its delineation. This paper reports an investigation on this issue, which comprised the review of climatic zoning methodologies for building energy efficiency programs adopted by 54 countries. The paper identified that the nature and magnitude of climatic variations are not the main elements in the definition of the number of climatic zones in a country. The number of climatic zones seems to be mainly driven by the expected simplicity of the final climatic zoning, respecting in most cases a maximum of 8 zones independent of the country size and climatic variations. A total of 19 different variables, techniques and parameters used in climatic zoning were identified, the most frequent being temperature, degree days, altitude, administrative divisions and relative humidity. However, around 80% of the countries analysed in this study used only up to three variables/techniques/parameters to define their climatic zoning. This simplicity comes at the cost of ignoring several aspects of climate and building energy performance. From the techniques identified in this review, only the combination of building performance simulation and cluster analysis seems to provide robust tools to tackle the complex relations between climate and building energy performance. Combined, these tools may provide the means to explore scenarios and support evidence-based decision making in energy policy. The lack of consensus in several aspects of climate zoning indicates the need for further research in this area. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach to incorporate the non-stationarities characterised in the GCM outputs, into the Predictor-Predictand Relationships (PPRs) in statistical downscaling models. In this approach, a series of 42 PPRs based on multi-linear regression (MLR) technique were determined for each calendar month using a 20-year moving window moved at a 1-year time step on the predictor data obtained from the NCEP/NCAR reanalysis data archive and observations of precipitation at 3 stations located in Victoria, Australia, for the period 1950–2010. Then the relationships between the constants and coefficients in the PPRs and the statistics of reanalysis data of predictors were determined for the period 1950–2010, for each calendar month. Thereafter, using these relationships with the statistics of the past data of HadCM3 GCM pertaining to the predictors, new PPRs were derived for the periods 1950–69, 1970–89 and 1990–99 for each station. This process yielded a non-stationary downscaling model consisting of a PPR per calendar month for each of the above three periods for each station. The non-stationarities in the climate are characterised by the long-term changes in the statistics of the climate variables and above process enabled relating the non-stationarities in the climate to the PPRs. These new PPRs were then used with the past data of HadCM3, to reproduce the observed precipitation. It was found that the non-stationary MLR based downscaling model was able to produce more accurate simulations of observed precipitation more often than conventional stationary downscaling models developed with MLR and Genetic Programming (GP). [ABSTRACT FROM AUTHOR]

The northern edge of the East Asian monsoon region is also a transition zone of temperate continental and monsoon climate, which is a sensitive zone of global climate and ecological environment change. It is an urgent problem to find out the long-term climate change rules of this region. Using 101 tree core samples obtained from 54 trees, a 343-year tree-ring width chronology of the Platycladus orientalis (L.) Franco (1673–2016) in the Wula Mountains, Inner Mongolia, China was established. The analysis shows that the radial growth of P. orientalis is closely related to hydrothermal conditions, the average minimum temperature and relative humidity are the main factors that determine the growth of P. orientalis. Based on the strong correlation between the tree-ring indices and the annual average minimum temperature (r = −0.870, p < 0.001), we reconstructed an average annual minimum temperature series from 1673 to 2016 using a linear regression equation, and the reconstructed equation can explain 75.724% of the variance, respectively. According to the data from the past 343 years, the changes in the annual average minimum temperature series had the cycles of 58.6-, 7.7-, 3.4-, 3.1-, 2.2-, and 2.1-years; the series showed three warm periods (1824–1830, 1909–1922, and 1986–2011) and 4 cold periods (1703–1712, 1731–1738, 1754–1763, and 1937–1951). The low temperature periods recorded in the reconstructed series for the 17th and 18th centuries are consistent with the Little Ice Age that occurred in the northern hemisphere, and the heating rate significantly increased at the end of the 20th century. In addition, the cold and warm periods recorded by the reconstruction result is basically consistent with the extreme climate events recorded in the historical documents of the region and the reconstruction results in other regions. In this paper, the world's first chronology of P. orientalis tree ring width was established. A historical sequence of annual average minimum temperature of 343 years was reconstructed in a typical region of the East Asian monsoon climate. It fills in the blank of reconstruction sequence and variation characteristics of mean minimum temperature in the northern edge of East Asian monsoon and transition zone of temperate continental and monsoon climate in recent four centuries. [ABSTRACT FROM AUTHOR]

The concentration of sugar in the nectars of unprotected flowers of several species was measured and did not reach the high values that would be in equilibrium with the daytime humidities recorded outside the corolla, although the sugar concentration was highly correlated with ambient relative humidity. This paper examines features that maintain low nectar sugar concentrations at low ambient humidities. Post-secretory changes in concentration are influenced to a small extent by nectar composition but depend largely on physico-chemical and microclimatic effects. Factors contributing to the maintenance of steep gradients in water activity between the nectar and the ambient air include corolla morphology, sugar concentration gradients and waterproofing lipid monolayers on the nectar surface. This paper considers the relative importance of such features in relation to the pollination syndrome. A simple technique is described for the measurement of intrafloral relative humidity. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the L.N. Gumilyov Eurasian National University. Technical science & Technology series is the property of L.N. Gumilyov Eurasian National University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Globally there is already a lot of pressure on water resources because of climate change, economic development, as well as an increasing global populace. Many rivers originate in the mountains, where snowfall fluctuations and the global climate's inherent unpredictability affect the hydrological processes. Climate change sensitivity has been recognized in recent years and would affect hydropower, such as humidity, cloudiness, and precipitation, that are considered; global warming emerges as one of the most important contributors to climate change. The Yangtze River supports rich biodiversity and provides important ecosystem services for human survival and development. In addition, climate changes, particularly short-term and long-term precipitation and temperature fluctuations, influence the snow regime and the hydrological development of river flow response at the basin and sub-basin scales. More precise this review focused to understand the hydropower potential, freshwater fisheries, and hydrological response of snow dynamics in snow-dominated basins. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kirkuk University for Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The South China Sea is a hotspot for regional climate research. Over the past 40 years, considerable improvement has been made in the development and utilization of the islands in the South China Sea, leading to a substantial change in the land-use of the islands. However, research on the impact of human development on the local climate of these islands is lacking. This study analyzed the characteristics of local climate changes on the islands in the South China Sea based on data from the Yongxing Island Observation Station and ERA5 re-analysis. Furthermore, the influence of urbanization on the local climate of the South China Sea islands was explored in this study. The findings revealed that the 10-year average temperature in Yongxing Island increased by approximately 1.11 °C from 1961 to 2020, and the contribution of island development and urbanization to the local warming rate over 60 years was approximately 36.2%. The linear increasing trend of the annual hot days from 1961-2020 was approximately 14.84 days per decade. The diurnal temperature range exhibited an increasing trend of 0.05 °C per decade, whereas the number of cold days decreased by 1.06 days per decade. The rapid increase in construction on Yongxing Island from 2005 to 2021 led to a decrease in observed surface wind speed by 0.32 m s-1 per decade. Consequently, the number of days with strong winds decreased, whereas the number of days with weak winds increased. Additionally, relative humidity exhibited a rapid decline from 2001 to 2016 and then rebounded. The study also found substantial differences between the ERA5 re-analysis and observation data, particularly in wind speed and relative humidity, indicating that the use of re-analysis data for climate resource assessment and climate change evaluation on island areas may not be feasible. [ABSTRACT FROM AUTHOR]

Mitigating the global climate crisis and its consequences, such as more frequent and severe droughts, is one of the major challenges for future agriculture. Therefore, identifying land use systems and management practices that reduce greenhouse gas (GHG) emissions and promote water use efficiency (WUE) is crucial. This, however, requires accurate and precise measurements of carbon dioxide (CO 2) fluxes and evapotranspiration (ET). Despite that, commercial systems to measure CO 2 and ET fluxes are expensive and thus often exclude research in ecosystems within the Global South. This is especially true for research and data of agroecosystems in these areas, which are to date still widely underrepresented. Here, we present a newly developed low-cost, non-dispersive infrared (NDIR)-based CO 2 and ET flux measurement device (∼ EUR 200) that provides reliable, accurate and precise CO 2 and ET flux measurements in conjunction with manually operated closed chambers. To validate the system, laboratory and field validation experiments were performed, testing multiple different low-cost sensors. We demonstrate that the system delivers accurate and precise CO 2 and ET flux measurements using the K30 FR NDIR (CO 2) and SHT31 (RH, relative humidity) sensor. An additional field trial application demonstrated its longer-term stability (> 3 months) and ability to obtain valid net ecosystem C balances (NECBs) and WUE. This was the case, even though environmental conditions at the field trial application site in sub-Saharan Africa were rather challenging (e.g., extremely high temperatures, humidity and rainfall). Consequently, the developed low-cost CO 2 and ET flux measurement device not only provides reasonable results but also might help with democratizing science and closing current data gaps. [ABSTRACT FROM AUTHOR]

In recent decades, China has experienced substantial climate change and significant vegetation greenness due to the extensive implementation of artificial ecological restoration programs. However, the quantitative contributions of climatic and anthropogenic drivers to the national variations in associated evapotranspiration (ET) and gross primary productivity (GPP) over China at different climate zoning sub-regions remain unclear. Based on the analysis of climate factor and vegetation disturbance trends created by anthropogenic activities, this study constructed a remote sensing-based ecological model consisting of Penman–Monteith–Leuning (PML) and light use efficiency (LUE) components. The proposed model simulated the spatiotemporal changes in ET and GPP between 1999 and 2018 over China. The contributions of climatic factors and anthropogenic activities to ET and GPP variations were quantitatively calculated by ridge regression. The results show that (1) both interannual ET and GPP markedly increased, by 1.32 mm yr−1 and 8.01 g C m−2 yr−1, respectively; (2) vegetation changes due to anthropogenic disturbance made the dominant contribution to GPP variations over China, while the dominant factor influencing ET changes differed by sub-region due to the joint effects of vegetation and climate; (3) temperature and precipitation positively affected ET, while wind speed, humidity, and solar radiation negatively contributed to ET in most parts of Mainland China. These findings may provide a workable, scientific reference for further ecological restoration decision-making processes in China. [ABSTRACT FROM AUTHOR]

The mid-Pliocene (approximately 3.3–3.0 Ma) was one of the past geological warm periods. Since this past warmer climate was in many respects comparable to near future warming projections, how the regional monsoonal rainfall changed during the mid-Pliocene is an important scientific and socioeconomic concern. Based on phase 2 of the Pliocene Model Intercomparison Project (PlioMIP2), this work examines the simulated changes of Sahel summer rainfall during the mid-Pliocene. The results show the considerable intermodel uncertainty of the simulated mid-Pliocene Sahel rainfall changes in the PlioMIP2 multimodel ensemble, which is due to the uncertainties of both the simulated dynamic and thermodynamic responses to this past warmer climate. In particular, we find that the intermodel spread in the simulated northern North American warming is a major source of the uncertainty of the mid-Pliocene Sahel summer rainfall changes through two processes. One is a direct dynamic process: a stronger warming over northern North America could enhance the meridional temperature gradient between the extratropical and tropical regions, inducing an interhemisphere energy imbalance of the atmosphere. This could lead to a northward shift of the intertropical convergence zone, strengthening the Western African summer monsoon (WASM) circulation and Sahel summer rainfall. Another is an indirect thermodynamic process: the strengthened WASM circulation could further induce anomalous moisture convergence over the Sahel region, increasing local atmospheric moisture at the low-level troposphere, in favor of a wetter Sahel. Our results suggest that an improved warming simulation over northern North America is essential for the hydrological cycle simulation around the Sahel in the mid-Pliocene warmer climate. Significance Statement: The Sahel summer rainfall change in a global warmer climate is a widespread scientific and socioeconomic issue because of its important impacts on regional agriculture, ecosystems, food security, water resources, and even cultural environment. However, the present study identifies a nonnegligible intermodel uncertainty of the simulated Sahel rainfall changes during the mid-Pliocene (one of the most recent geological warm periods in Earth's history) in the Pliocene Model Intercomparison Project phase 2 (PlioMIP2) multimodel ensemble. In particular, such an intermodel uncertainty of the simulated Sahel rainfall changes during the mid-Pliocene is attributed to that of the simulated northern North America warming via both the direct dynamic process and the indirect thermodynamic process. This is quite different from the uncertainty source of near-future projections of Sahel summer rainfall changes. The present results improve our understanding of the underlying physics of the hydrological cycle change around the Sahel region in the mid-Pliocene warmer climate, with implications for the future projections of regional monsoonal rainfall. [ABSTRACT FROM AUTHOR]

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This paper assesses intermodel spread in the slope of global-mean precipitation change Δ P with respect to surface temperature change. The ambiguous estimates in the literature for this slope are reconciled by analyzing four experiments from phase 5 of CMIP (CMIP5) and considering different definitions of the slope. The smallest intermodel spread (a factor of 1.5 between the highest and lowest estimate) is found when using a definition that disentangles temperature-independent precipitation changes (the adjustments) from the slope of the temperature-dependent precipitation response; here this slope is referred to as the hydrological sensitivity parameter η. The estimates herein show that η is more robust than stated in most previous work. The authors demonstrate that adjustments and η estimated from a steplike quadrupling CO2 experiment serve well to predict Δ P in a transient CO2 experiment. The magnitude of η is smaller in the coupled ocean-atmosphere quadrupling CO2 experiment than in the noncoupled atmosphere-only experiment. The offset in magnitude due to coupling suggests that intermodel spread may undersample uncertainty. Also assessed are the relative contribution of η, the surface warming, and the adjustment on the spread in Δ P on different time scales. Intermodel variation of both η and the adjustment govern the spread in Δ P in the years immediately after the abrupt forcing change. In equilibrium, the uncertainty in Δ P is dominated by uncertainty in the equilibrium surface temperature response. A kernel analysis reveals that intermodel spread in η is dominated by intermodel spread in tropical lower tropospheric temperature and humidity changes and cloud changes. [ABSTRACT FROM AUTHOR]

To address the problems and limitations identified through a comprehensive evaluation in Part I paper, several modifications are made in model inputs, treatments, and configurations and sensitivity simulations with improved model inputs and treatments are performed in this Part II paper. The use of reinitialization of meteorological variables reduces the biases and increases the spatial correlations in simulated temperature at 2-m (T2), specific humidity at 2-m (Q2), wind speed at 10-m (WS10), and precipitation (Precip). The use of a revised surface drag parameterization further reduces the biases in simulated WS10. The adjustment of only the magnitudes of anthropogenic emissions in the surface layer does not help improve overall model performance, whereas the adjustment of both the magnitudes and vertical distributions of anthropogenic emissions shows moderate to large improvement in simulated surface concentrations and column mass abundances of species in terms of domain mean performance statistics, hourly and monthly mean concentrations, and vertical profiles of concentrations at individual sites. The revised and more advanced dust emission schemes can help improve PM predictions. Using revised upper boundary conditions for O 3 significantly improves the column O 3 abundances. Using a simple SOA formation module further improves the predictions of organic carbon and PM 2.5 . The sensitivity simulation that combines all above model improvements greatly improves the overall model performance. For example, the sensitivity simulation gives the normalized mean biases (NMBs) of −6.1% to 23.8% for T2, 2.7–13.8% for Q2, 22.5–47.6% for WS10, and −9.1% to 15.6% for Precip, comparing to −9.8% to 75.6% for T2, 0.4–23.4% for Q2, 66.5–101.0% for WS10, and 11.4%–92.7% for Precip from the original simulation without those improvements. It also gives the NMBs for surface predictions of −68.2% to −3.7% for SO 2 , −73.8% to −20.6% for NO 2 , −8.8%–128.7% for O 3 , −61.4% to −26.5% for PM 2.5 , and −64.0% to 7.2% for PM 10 , comparing to −84.2% to −44.5% for SO 2 , −88.1% to −44.0% for NO 2 , −11.0%–160.3% for O 3 , −63.9% to −25.2% for PM 2.5 , and −68.9%–33.3% for PM 10 from the original simulation. The improved WRF/Chem is applied to estimate the impact of anthropogenic aerosols on regional climate and air quality in East Asia. Anthropogenic aerosols can increase cloud condensation nuclei, aerosol optical depth, cloud droplet number concentrations, and cloud optical depth. They can decrease surface net radiation, temperature at 2-m, wind speed at 10-m, planetary boundary layer height, and precipitation through various direct and indirect effects. These changes in turn lead to changes in chemical predictions in a variety of ways. [ABSTRACT FROM AUTHOR]

The Baltic Sea coasts hold huge potential for summer beaching in the 21st century. The appropriate temperature and precipitation regime are prior to Mediterranean Sea climatic conditions which become too hot with regular heat waves in summer. The originally designed method allows to evaluate more “precise” UTCI values (in °C) using averaged monthly data of meteorological variables (air temperature, humidity, wind velocity, cloudiness, and atmospheric pressure) instead of daily values. The evaluation in this paper covers the period from 1980 to 2009. Only the summer beaching period (May–September) was analysed. The initial data was taken from the European Climate Assessment & Dataset project database. The monthly reanalysis fields of meteorological variables were used for covering the Baltic Sea coasts and adjacent territories (180 grid points). The UTCI values were obtained using BioKlima version 2.6 software. The UTCI values were visualized using ArcGIS 10.2 version software. The evaluation period was divided into two parts (1980–1994 and 1995–2009). The results showed that the temporal and spatial changes are already happening on the coastline. The UTCI values became higher in almost the entire perimeter of the Baltic Sea coastline and the warming process included every summer month. The whole Baltic Sea coastline corresponds to comfortable conditions (UTCI >9°C) of the UTCI categorization from May to August. Only in September did conditions become less comfortable. However, the real “thermal comfort zone” conditions (UTCI >17.5°C) on the Baltic Sea coasts last from the middle of June until the middle of August. The southern part is significantly warmer compared to other parts in May and September, while the UTCI values are more similar over the other summer months. [ABSTRACT FROM AUTHOR]

The paper introduces a novel method for risk assessment and preventive conservation of organic hygroscopic cultural heritage objects. The method is based on the analysis of the historic climate that is established in the European Standard EN 15757:2010. This new approach enables interpreting visible damage and assessing cause–effect relationships and it finds practical application in improving conservation strategies for real life buildings and objects. The paper investigates how it may be advantageous to reconstruct the historic climate back in time to obtain sound information about the target relative humidity (RH) level and the domain of RH fluctuations that can be considered safe for conservation. The method was applied to an inlaid wooden choir in the basilica of S. Giustina, Padua, Italy. The past indoor climate has been reconstructed over the whole life of the object, built in 1477, with documentary proxy data, instrumental readings and building simulation. Winter has been found to be the most critical season for the mechanical stress and wood yield. For the future, the indoor climate has been simulated until 2100 to timely devise preventive conservation measures to reduce the risk induced by climate change. Finally an evaluation of uncertainties has been considered. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings of the Estonian Academy of Sciences is the property of Teaduste Akadeemia Kirjastus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper analyzed the spatial and temporal variations of surface relative humidity in Nigeria in the context of climate variability and change. The study is based on the data collected from the Nigerian Meteorological Agency, Oshodi, Lagos Nigeria for the period ranging from 1950 - 2012 with variations in data length across the stations. Basic data consist of monthly mean daily relative humidity values expressed in percent at 0900 hours GMT from 20 meteorological stations spread across different ecological zones and climate belts in Nigeria. Statistical techniques used for the analyses include time series plots, correlation analysis, descriptive statistics, Mann-Kendall's rank correlation tests, bar charts and the least square linear fitting of the linear regression model. These analyses were executed using MATLAB 2008, SPSS version 17 and the 'R' programming language software packages. The descriptive statistics indicate that the mean and the coefficient of variation show latitudinal dependence. The Mann-Kendall's tests results show that 4 stations (representing 20%) show significant downward trends while 3 stations (representing 15%) show significant upward trends at the 1% and 5% levels with no discernible pattern across latitudinal bands. The inter station correlation as revealed by the Pearson's product moment correlation coefficients show strong positive correlations significant at the 1% level across all station pairs. The bar charts show more marked seasonal variations in the north than in the south with peak values from June to October and minimum extending from November to March across Nigeria. The results suggest that the spatial variability of surface relative humidity is impacted by some local processes and local clouds as the spatial and temporal trends are not consistent with the increasing global temperatures based on positive feedback of water vapour on surface temperature in model simulations. [ABSTRACT FROM AUTHOR]

The question of why, in the annual-mean, the northern hemisphere (NH) is warmer than the southern hemisphere (SH) is addressed, revisiting an 1870 paper by James Croll. We first show that ocean is warmer than land in general which, acting alone, would make the SH, with greater ocean fraction, warmer. Croll was aware of this and thought it was caused by greater specific humidity and greenhouse trapping over ocean than over land. However, for any given temperature, it is shown that greenhouse trapping is actually greater over land. Instead, oceans are warmer than land because of the smaller surface albedo. However, hemispheric differences in planetary albedo are negligible because the impact of differences in land-sea fraction are offset by the SH ocean and land reflecting more than their NH counterparts. In the absence of a role for albedo differences it is shown that, in agreement with Croll, northward cross-equatorial ocean heat transport (X-OHT) is critical for the warmer NH. This is examined in a simple box model based on the energy budget of each hemisphere. The hemispheric difference forced by X-OHT is enhanced by the positive water vapor-greenhouse feedback, and is partly compensated by the southward atmospheric energy transport. Due to uncertainties in the ocean data, a range of X-OHT is considered. A X-OHT of larger than 0.5 PW is needed to explain the warmer NH solely by X-OHT. For smaller X-OHT, a larger basic state greenhouse trapping in the NH, conceived as imposed by continental geometry, needs to be imposed. Numerical experiments with a GCM coupled to a slab ocean provide evidence that X-OHT is fundamentally important in determining the hemispheric differences in temperature. Therefore, despite some modifications to his theory, analysis of modern data confirms Croll's 140-year-old theory that the warmer NH is partly because of northward X-OHT. [ABSTRACT FROM AUTHOR]

Previous work by the same authors has shown that in mixed-humid climates, tight, super-insulated residential structures can experience high humidity events in summer months. Standard, commercially available vapor compression-based air conditioners struggle to control humidity in such structures with low cooling loads. Therefore a desiccant-assisted heat pump system for tight, super-insulated residential structures is proposed. This paper first reviews solid desiccant cooling cycles. Then a hybrid desiccant cooling cycle is explained and a prototype machine based on the cycle is described. The machine, known as HAWC (hybrid air/water conditioner), accomplishes cooling, dehumidification, ventilation, and domestic hot water heating. This paper models the HAWC within the framework of dynamic building energy modeling software and concludes that a refined version of the HAWC prototype is capable of completely eliminating high humidity events in the summer time while still saving energy as compared to a traditional HVAC system. [ABSTRACT FROM AUTHOR]

Background Over the last decade, the incidence of confirmed malaria has declined significantly in Nepal. The aim of this paper is to assess the spatio-temporal distribution of malaria and its association with climatic factors and vector control interventions in two high-risk districts of Nepal. Methods Hotspot analysis was used to visualize the spatio-temporal variation of malaria incidence over the years at village level and generalized additive mixed models were fitted to assess the association of malaria incidence with climatic variables and vector control interventions. Results Opposing trends of malaria incidence were observed in two high-risk malaria districts of eastern and far-western Nepal after the introduction of long-lasting insecticidal nets (LLINs). The confirmed malaria incidence was reduced from 2.24 per 10,000 in 2007 to 0.31 per 10,000 population in 2011 in Morang district but increased from 3.38 to 8.29 per 10,000 population in Kailali district. Malaria hotspots persisted mostly in the same villages of Kailali district, whereas in Morang district malaria hotspots shifted to new villages after the introduction of LLINs. A 1° C increase in minimum and mean temperatures increased malaria incidence by 27% (RR =1.27, 95% CI =1.12-1.45) and 25% (RR =1.25, 95% CI =1.11-1.43), respectively. The reduction in malaria incidence was 25% per one unit increase of LLINs (RR =0.75, 95% CI =0.62-0.92). The incidence of malaria was 82% lower in Morang than in Kailali district (RR =0.18, 95% CI =0.11-0.33). Conclusions The study findings suggest that LLIN coverage should be scaled up to entire districts rather than high-incidence foci only. Climatic factors should be considered for malaria microstratification, mosquito repellents should be prescribed for those living in forests, forest fringe and foothills and have regular visits to forests, and imported cases should be controlled by establishing fever check posts at border crossings. [ABSTRACT FROM AUTHOR]

In this paper, the climate change in Haiyan County in recent decades was analyzed in detail with the methods of moving average, Mann-Kendall non-parametric mutation test and wavelet analysis. According to the variation trend of meteorological factors such as temperature, relative humidity, wind speed, pan evaporation and precipitation in recent decades, the climate of Haiyan County has a tendency of drought, which is becoming more and more serious. From the results of the analysis, the sunshine hours and the air temperature in Haiyan County have an obvious upward trend. The average surface temperature has increased by 2.75 °C from 1976, and its largest increase occurred in the late 1970s and 1980s. At this stage, the average surface temperature increased by 1.37 °C. The relative humidity has a decreasing trend that has decreased by 2.75%. From 1976 to the present, there are two quasi-3a cycles and one quasi-6a cycle. The precipitation and evaporation showed the opposite change trend, in which the trend of precipitation fluctuated upward, while the trend of evaporation showed a fluctuating downward tendency, which led to the serious loss of water in the feeding area. The wind direction in Haiyan County are mainly from west to east, and its wind speed has a trend of slight increase. [ABSTRACT FROM AUTHOR]

Global and regional climate change is disturbing all sectors of the national economy. The most affected is agriculture, which takes place under open sky. Bulgaria is located in area with insufficient atmospheric and soil moisture. Climate change cause changes in agro-meteorological conditions and agro-climatic resources, depending on the geographical location. All agro technical activities - sowing, soil cultivation, fertilization, plant protection and harvesting, are highly dependent on weather conditions. The crops development, quantity and quality of production are determined to a great extent by the weather conditions, in particular, by those which have an adverse effect on plants and production processes such as drought, torrential rain and hail. Agricultural production is connected with many risks. Therefore, solving problems in this production area must be linked to agro-climatic and agro-meteorological research to improve agro-technologies with aim to mitigate the effects of climate change and adapt the agriculture sector to these changes. The purpose of this study is to define trends in production and average yields of basic agricultural crops in Bulgaria over the last two decades in climate change and different weather conditions. [ABSTRACT FROM AUTHOR]

Arid and semi-arid regions of the world are particularly vulnerable to greenhouse gas-driven hydroclimate change. Climate models are our primary tool for projecting the future hydroclimate that society in these regions must adapt to, but here, we present a concerning discrepancy between observed and model-based historical hydroclimate trends. Over the arid/semi-arid regions of the world, the predominant signal in all model simulations is an increase in atmospheric water vapor, on average, over the last four decades, in association with the increased water vapor-holding capacity of a warmer atmosphere. In observations, this increase in atmospheric water vapor has not happened, suggesting that the availability of moisture to satisfy the increased atmospheric demand is lower in reality than in models in arid/semi-arid regions. This discrepancy is most clear in locations that are arid/semi-arid year round, but it is also apparent in more humid regions during the most arid months of the year. It indicates a major gap in our understanding and modeling capabilities which could have severe implications for hydroclimate projections, including fire hazard, moving forward. [ABSTRACT FROM AUTHOR]

Mountain lee waves present significant hazards to aviation, often inducing turbulence and aircraft icing. The current study focuses on understanding the potential impact of global climate change on the precursor environments to mountain lee wave cloud episodes over central Iberia. We examine the suitability of several Global Climate Models (GCMs) from CMIP6 in predicting these environments using the ERA5 reanalysis as a benchmark for performance. The dataset is divided into two periods: historical data (2001–2014) and projections for the SSP5–8.5 future climate scenario (2015–2100). The variations and trends in precursor environments between historical data and future climate scenarios are exposed, with a particular focus on the expansion of the Azores High towards the Iberian Peninsula, resulting in increased zonal winds throughout the Iberian Peninsula in the future. However, the increase in zonal wind is insufficient to modify the wind pattern, so future mountain lee wave cloud events will not vary significantly. The relative humidity trends reveal no significant changes. Moreover, the risk of icing precursor environments connected with mountain lee wave clouds is expected to decrease in the future, due to rising temperatures. Our results highlight that the EC-EARTH3 GCM reveals the closest alignment with ERA5 data, and statistically significant differences between the historical and future climate scenario periods are presented, making EC-EARTH3 a robust candidate for conducting future studies on the precursor environments to mountain lee wave cloud events. [ABSTRACT FROM AUTHOR]

Simple Summary: Our study shows that the African citrus psyllid, a vector of Huanglongbing disease, prefers to develop at mild temperatures and is not well adapted to dry regions, where relative humidity is around or below 40%. Its life cycle is not completed or is severely delayed at temperatures above 30 °C and below 10 °C. Eggs are unable to hatch at constant temperatures below 8 °C or above 33 °C. Thus, T. erytreae establishment and spread will be maximum in regions with a temperate and humid climate, being rare in regions where dry weather conditions predominate. The African citrus psyllid, Trioza erytreae, is one of the two vectors of Huanglongbing, the most serious citrus disease worldwide. The first detection of T. erytreae in the European mainland was on the northwest of the Iberian Peninsula in 2014. Since then, the pest has spread throughout northern Spain (Galicia, Asturias, Cantabria, País Vasco) and along the western Atlantic coast of Portugal (from the Douro e Minho region to the Algarve). We conducted a series of laboratory experiments on lemon plants at different temperatures (from 8 to 34 °C) and humidity conditions (from 40 to 90%) to find out the influence of extreme temperatures and relative humidities (RHs) on the mortality, development and reproduction of T. erytreae. Our results show that temperatures above 30 °C and below 10 °C are very detrimental for nymphal development and nymphs were unable to reach the adult stage. Furthermore, eggs were unable to hatch under temperatures above 33 °C and below 8 °C. Adult mortality was highest at 34 °C and killed more than 50% of the population. We also found that relative humidity is crucial for the development and survival of T. erytreae. Nymphs were unable to reach the adult stage at an RH of 90% and 40%. Also, fecundity was significantly reduced at 90 and 40% RH, and fertility was lowest at 40% RH. Nymphal mortality was highest at an RH of 40%, which was the most detrimental humidity among all tested for the survival and development of T. erytreae. Our work concludes that T. erytreae establishment and spread will be maximum in regions with a temperate and humid climate, being rare in regions where dry and hot weather conditions predominate. [ABSTRACT FROM AUTHOR]

Addressing the impacts of climate change requires, first of all, understanding the mechanisms driving changes, especially at the regional scale. In particular, policymakers and other stakeholders need physically robust climate change information to drive societal responses to a changing climate. This study analyses late 21st-century (2071–2100) precipitation projections for the Congo Basin under representative concentration pathway (RCP) 8.5, using the Rossby Centre Regional Climate Model (RCM) RCA4. Specifically, we examine the impact of the RCM formulation (reduction of turbulent mixing) on future change in seasonal mean precipitation by comparing the results of the modified model version (RCA4-v4) with those of the standard version (RCA4-v1) used in CORDEX (Coordinated Regional Climate Downscaling Experiment). The two RCM versions are driven by two global climate models participating in the Coupled Model Intercomparison Project phase 5 (CMIP5). The results show that seasonal precipitation is largely affected by modifications in the atmospheric column moisture convergence or divergence, and, in turn, associated with changes in the dynamic (ΔDY) and thermodynamic (ΔTH) components of the moisture-budget equation. Projected decreased precipitation in the dry seasons (December–January–February and June–July–August) is linked to increased moisture divergence driven by dynamic effects (changes in circulation), with most experiments showing ΔDY as the main contributor (>60%) to the total moisture budget. Overall, precipitation is projected to increase in the wet seasons (March–April–May and September–October–November), which can be attributed to both dynamic and thermodynamic effects, but with a larger thermodynamic contribution (changes in specific humidity, ΔTH > 45%), compared to the dynamic one (ΔDY > 40%). Through a comparison of the two model versions, we found that the formulation (reducing turbulent mixing) and boundary conditions (driving GCM) strongly influence precipitation projections. This result holds substantial value for ensuring the fitness of models for future projections intended for decision-makers. [ABSTRACT FROM AUTHOR]

In the context of the predicted global warming, we investigated whether the feeding activity and the behaviour of three Oniscidean species (Porcellionides pruinosus, Porcellio laevis and Armadillidium tunisiense) would be affected by the relative humidity (RH) decrease. A decreasing gradient of relative humidity (90%, 70% and 50%) was used to study the impact of predicted climate change on the survival rate, litter consumption rate, growth efficiency, faeces production, localization and stress behaviour within woodlice. After 3 weeks of exposure, we found that all species were variously affected by the RH decrease. The species A. tunisiense showed to be the least affected by the increased dry conditions. In driest conditions, woodlice spend less time at foraging inducing a low rate of litter consumption and faeces production. Perhaps, the authors findings could contribute to changes in the decomposition process and then the soil functionality. [ABSTRACT FROM AUTHOR]

There has been considerable debate about the degree to which climate has driven societal changes in the eastern Mediterranean region, partly through reliance on a limited number of qualitative records of climate changes and partly reflecting the need to disentangle the joint impact of changes in different aspects of climate. Here, we use tolerance-weighted, weighted-averaging partial least squares to derive reconstructions of the mean temperature of the coldest month (MTCO), mean temperature of the warmest month (MTWA), growing degree days above a threshold of 0 ∘ C (GDD0), and plant-available moisture, which is represented by the ratio of modelled actual to equilibrium evapotranspiration (α) and corrected for past CO 2 changes. This is done for 71 individual pollen records from the eastern Mediterranean region covering part or all of the interval from 12.3 ka to the present. We use these reconstructions to create regional composites that illustrate the long-term trends in each variable. We compare these composites with transient climate model simulations to explore potential causes of the observed trends. We show that the glacial–Holocene transition and the early part of the Holocene was characterised by conditions colder than the present. Rapid increases in temperature occurred between ca. 10.3 and 9.3 ka, considerably after the end of the Younger Dryas. Although the time series are characterised by centennial to millennial oscillations, the MTCO showed a gradual increase from 9 ka to the present, consistent with the expectation that winter temperatures were forced by orbitally induced increases in insolation during the Holocene. The MTWA also showed an increasing trend from 9 ka and reached a maximum of ca. 1.5 ∘ C greater than the present at ca. 4.5 and 5 ka, followed by a gradual decline towards present-day conditions. A delayed response to summer insolation changes is likely a reflection of the persistence of the Laurentide and Fennoscandian ice sheets; subsequent summer cooling is consistent with the expected response to insolation changes. Plant-available moisture increased rapidly after 11 ka, and conditions were wetter than today between 10 and 6 ka, but thereafter, α declined gradually. These trends likely reflect changes in atmospheric circulation and moisture advection into the region and were probably too small to influence summer temperature through land–surface feedbacks. Differences in the simulated trajectory of α in different models highlight the difficulties in reproducing circulation-driven moisture advection into the eastern Mediterranean. [ABSTRACT FROM AUTHOR]

During and after recent La Niña events, the decline of the eastern East African (EA) March‐April‐May (MAM) rains has set the stage for life‐threatening sequential October‐November‐December (OND) and MAM droughts. The MAM 2022 drought was the driest on record, preceded by three poor rainy seasons, and followed by widespread starvation. Connecting these dry seasons is an interaction between La Niña and climate change. This interaction provides important opportunities for long‐lead prediction and proactive disaster risk management, but needs exploration. Here, for the first time, we use observations, reanalyses, and climate change simulations to show that post‐1997 OND La Niña events are robust precursors of: (a) strong MAM "Western V sea surface temperature Gradients" in the Pacific, which (b) help produce large increases in moisture convergence and atmospheric heating near Indonesia, which in turn produce (c) regional shifts in moisture transports and vertical velocities, which (d) help explain the increased frequency of dry EA MAM rainy seasons. We also show that, at 20‐year time scales, increases in atmospheric heating in the Indo‐Pacific Warm Pool region are attributable to warming Western V SST, which is in turn largely attributable to climate change. As energy builds up in the oceans and atmosphere, during and after La Niña events, we see stronger heating and heat convergence over warm tropical waters near Indonesia. The result of this causal chain is that increased Warm Pool atmospheric heating and moisture convergence sets the stage for dangerous sequential droughts in EA. These factors link EA drying to a stronger Walker Circulation and explain the predictable risks associated with recent La Niña events. Plain Language Summary: In 2022, an unprecedented sequence of five sequential failed rainy seasons, exacerbated by high global food and fuel prices, drove an exceptional food security crisis in Ethiopia, Somalia, and Kenya, pushing more than 20 million people into extreme hunger. The potential for famine loomed in some areas. Beginning in late 2020, this was the longest and most severe drought recorded in the Horn of Africa in at least 70 years, resulting in multiple failed harvests and large‐scale livestock deaths that decimated the food and income sources of rural communities. It placed increasing pressure on the cost of food among urban communities and led to rising levels of destitution and displacement. These droughts occurred against the backdrop of the "East Africa Climate Paradox", which centers on the discrepancy between climate change model projections of increased East African March–April–May rains, and many observational studies pointing toward declines. Before the western Pacific Ocean warmed dramatically in 1998, the link between La Niña events and dry March‐April‐May (MAM) rains was weak. Since 1998, the link has been very strong. This set the stage for dangerous sequential droughts in October‐November‐December and MAM, such as in 2010/11, 2016/17, 2020/21, and 2021/22. Here, we link the decline to an important question: Why are so many recent La Niña events associated with dry March–April–May rains? La Niña events tend to reach their maximum intensity in the boreal fall and winter, often producing East African droughts during the October‐November‐December "short rains". We explain the link between La Niña and dry MAM seasons using observations, reanalyses, and the latest (Phase 6) climate change simulations. While climate change models do not recreate the observed East African drying, they recreate the observed west Pacific warming very well. Climate change, not natural decadal variability associated with the Pacific Decadal Oscillation, has increased west Pacific sea surface temperatures. This, in turn, is increasing the "Western V Gradient", a measure of the east‐west differences in Pacific Ocean temperatures. When this gradient is negative, there are frequent East African droughts, and this happens in a predictable way during or after recent La Niña events. This allows us to predict many dry rainy seasons approximately 8 months in advance. Such predictive capacity is important, because the frequency of strong Pacific temperature gradients is increasing. We show that climate change simulations recreate this tendency for stronger Pacific SST gradients, and project that it will continue over the coming decades. What connects East African droughts to Pacific temperature gradients? We answer this question by examining observed atmospheric heating, moisture transports, and moisture convergence patterns. In general, eastern East Africa is dry because it resides along the western edge of the Indian Ocean branch of the Indo‐Pacific "Walker Circulation". Across eastern East Africa and the western Indian Ocean, and over the central and eastern Pacific, rainfall and moisture levels are low. In the area around Indonesia (the eastern Indian and western Pacific Oceans), winds drive moisture convergence and heavy rains. Here, building on many years of research by scientists working for the Famine Early Warning Systems Network, we show for the first time that the strength of the Walker Circulation can be quantified using atmospheric heating and moisture convergence. Since 1998, when there has been a La Niña in October–November–December, there has almost always been strong March‐April‐May heating and moisture convergence around Indonesia, and suppressed rainfall in eastern East Africa. Climate change‐enhanced La Niñas amplify the Pacific trade winds which produce strong March–April–May sea surface temperature gradients. These gradients amplify the Walker Circulation, and reduce moisture convergence and ascending atmospheric motions over the eastern Horn of Africa. We conclude with a look toward the future evolution of the Walker Circulation by relating the observed strength of the Walker Circulation to 20‐year averages of western and eastern Pacific sea surface temperatures. Both play a significant role, and together explain 96% of the observed variability. The observed Walker Circulation intensification is primarily driven by the west Pacific, which in turn is strongly related to climate change. CMIP6 projections of Pacific sea surface temperatures, combined with the observed empirical relationships, imply further strong increases in Walker Circulation intensities. Hence, additional rainfall declines appear likely, especially during or directly following La Niña events. More optimistically, the process‐based analyses presented here suggest that many of the dry seasons may be predictable at long lead times, based on Pacific sea surface temperature gradients. Key Points: Human‐induced warming in the Western V region of the Pacific, combined with La Niña, has produced frequent, predictable March‐April‐May droughtsThermodynamic analyses link these droughts to a stronger Walker Circulation driven by predictable warming in the Western V regionProjected CMIP6 SST increases imply a tendency for continued Walker Circulation intensification and associated drought risks in eastern East Africa [ABSTRACT FROM AUTHOR]

Based on the daily data of relative humidity from 23 meteorological stations in the Tarim River Basin of northwest China during the period from 1961 to 2010, this paper analyzed the multifractal and long memory property of humidity process. Main findings are as follows: (1) The processes present scaling and multifractal property. (2) The left-skewed multifractal spectrum f( α) indicates that the time series of relative humidity is predominated by small fluctuations. (3) There exists long memory with the δ ∈ (0, 0.5) in the processes, except for Kalpin and Aksu's exhibiting non-stationary long memory with the parameter δ being 0.67 and 0.69 respectively. (4) We found that on the whole, the degree of multifractality exhibits a strengthening trend with the longitude and latitude increasing, but decreasing trend with elevation rising; For length of long memory, we investigated that on the whole, the δ values increased with the longitude and latitude increasing, which indicates that the bigger the longitude and latitude is, the longer the memory of humidity process is, but the higher the elevation is, the shorter the memory of humidity process is. [ABSTRACT FROM AUTHOR]

The explanation for climate change is still searching for an experimental proof and the most important question is whether climate change is anthropogenic. According to the Intergovernmental Panel on Climate Change IPCC global warming is mostly man made due to the increasing CO2 concentration. In this work we study the contributions of humidity and clouds to the surface temperature. We will show that changes of relative humidity or low cloud cover explain the major changes in the global mean temperature. We will present the evidence of this argument using the observed relative humidity between years 1970 and 2011 and the observed low cloud cover between years 1983 and 2008. One percent increase in relative humidity or in low cloud cover decreases the temperature by 0.15 °C and 0.11 °C, respectively. In the time periods mentioned before the contribution of the CO2 increase was less than 10% to the total temperature change. [ABSTRACT FROM AUTHOR]

In this study, the hydrologic and hydraulic processes occurring in green roofs are analyzed and the similarities and differences in the rainfall-runoff transformation between green roofs and regular catchments are identified. Analytical equations, which can be used to evaluate the long-term average runoff reduction rates, fractions of time when irrigation is needed, and irrigation water requirements of both extensive and intensive green roofs with or without storage layers, are derived by modifying or extending the analytical probabilistic model which was previously developed to model probabilistically the rainfall-runoff processes occurring on regular catchments. The accuracy of these analytical equations is verified by comparing with continuous simulation results. Also demonstrated in this paper are the performances of green roofs with widely different hydrologic designs under arid and humid climate conditions. [ABSTRACT FROM AUTHOR]

This paper studies the climatic conditions of warm and cold dry months in the humid and semi-humid Argentine region and some aspects of the regional circulation related to these cases. The climatic analysis of warm (temperatures above percentile 80) and cold (temperatures below percentile 20) dry months is based on precipitation and temperature data registered at reference stations over a period of at least 70 years, while the associated circulation is derived from daily data of geopotential height at 500 hPa from NCEP-DOE Reanalysis 2 database. The reference station for the center of the country registered a greater number of warm dry months during both the warm season (October-March) and the cold season (April-September), whereas the reference stations in the north-east and center-east showed differences depending on the time of the year, with more cold dry months during the April-September season and more warm dry months in the October-March season. A classification of daily fields of geopotential height anomalies at 500 hPa was used to analyze the atmospheric circulation related to warm and cold dry months. The circulation patterns were obtained by applying principal component analysis and cluster analysis. Findings show that some mid-level circulation patterns occur with a significant different frequency during the warm dry months or the cold dry months studied. Finally, cases of spatially extended precipitation-deficit conditions (hereinafter generalized droughts) were studied, noting dominant patterns that are coherent with the previous results. [ABSTRACT FROM AUTHOR]

This paper examines possible adaptations to climate change in terms of pasture and crop land use and stocking rate in the United States (U.S.). Using Agricultural Census and climate data in a statistical model, we find that as temperature and precipitation increases agricultural commodity producers respond by reducing crop land and increasing pasture land. In addition, cattle stocking rate decreases as the summer Temperature-humidity Index (THI) increases and summer precipitation decreases. Using the statistical model with climate data from four General Circulation Models (GCMs), we project that land use shifts from cropping to grazing and the stocking rate declines, and these adaptations are more pronounced in the central and the southeast regions of the U.S. Controlling for other farm production variables, crop land decreases by 6 % and pasture land increases by 33 % from the baseline. Correspondingly, the associated economic impact due to adaptation is around −14 and 29 million dollars to crop producers and pasture producers by the end of this century, respectively. The national and regional results have implications for farm programs and subsidy policies. [ABSTRACT FROM AUTHOR]

This paper presents a discussion on assessing the potential impacts of climate change on the atmospheric corrosion rates of exposed steel structures. The effects on atmospheric corrosion due to changes in the environmental temperature, carbon dioxide, relative humidity, wind, rainfall and pollution are considered. The limitations and complexities of these assessments are discussed. To demonstrate the use and limitations of this science to evaluate effects related to climate change, a model developed in Australia to predict corrosion is combined with climate change models to project the change in the corrosion rates of steel components and protective zinc coatings in constructions. The method is applied to constructions located along the coastal areas of two Australian cities: Melbourne and Brisbane. These assessments are made using the A1FI scenario, the highest emission scenario defined by the Intergovernmental Panel on Climate Change, applied to nine general circulation models. The projected changes in corrosion rates were found to be an increase of ∼14% for both zinc and steel in Brisbane and a decrease of ∼14% for steel and 9% for zinc in Melbourne. It was also found that the uncertainties associated with the climate change models were small compared to those involved in modelling corrosion for engineering purposes. [ABSTRACT FROM AUTHOR]

This paper compares three existing Palmer Drought Severity Index (PDSI) formulations for simulating summer moisture variability in western Canada and a preliminary analysis of climate change impacts on summer moisture anomalies. The three models considered are Palmer's original algorithm (orPDSI), the self-calibrating PDSI (scPDSI), and a version modified for Canadian Prairie conditions (cpPDSI). In all formulations, potential evapotranspiration was parameterized by the Penman-Monteith method instead of the traditional Thornthwaite method. The scPDSI was used as a benchmark for evaluation as it is more appropriate for comparing drought severity of diverse climates. The results confirm that orPDSI produces inflated drought statistics as compared to scPDSI, whereas cpPDSI produced more conservative drought statistics than scPDSI. On the basis of results from scPDSI, historical moisture availability in the Canadian Prairies has shown a significant downward trend since 1950 at the 5% level, whereas southern British Columbia has shown a significant increasing trend. No discernible trend was found in the northern parts of the study area. These results were corroborated by trends in annual precipitation and summer temperature over the respective regions. When scPDSI parameters were calibrated using historical climate data, simulations for the 2050s using climate change scenarios from the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4) showed increases in summer moisture deficit relative to the 1961-90 baseline. However, projecting the extent to which the frequency of extreme drought and/or wet spell categories will change is not trivial since the computation of scPDSI is tied to the definition of the frequency of extreme events. [ABSTRACT FROM AUTHOR]

Fire danger indices are descriptors of fire potential in a large area, and combine a few variables that affect the initiation, spread and control of forest fires. The Canadian Fire Weather Index (FWI) is one of the most widely used fire danger indices in the world, and it is built upon instantaneous values of temperature, relative humidity and wind velocity at noon, together with 24 hourly accumulated precipitation. However, the scarcity of appropriate data has motivated the use of daily mean values as surrogates of the instantaneous ones in several studies that aimed to assess the impact of global warming on fire. In this paper we test the sensitivity of FWI values to both instantaneous and daily mean values, analyzing their effect on mean seasonal fire danger (seasonal severity rating, SSR) and extreme fire danger conditions (90th percentile, FWI90, and FWI>30, FOT30), with a special focus on its influence in climate change impact studies. To this aim, we analyzed reanalysis and regional climate model (RCM) simulations, and compared the resulting instantaneous and daily mean versions both in the present climate and in a future scenario. In particular, we were interested in determining the effect of these datasets on the projected changes obtained for the mean and extreme seasonal fire danger conditions in future climate scenarios, as given by a RCM. Overall, our results warn against the use of daily mean data for the computation of present and future fire danger conditions. Daily mean data lead to systematic negative biases of fire danger calculations. Although the mean seasonal fire danger indices might be corrected to compensate for this bias, fire danger extremes (FWI90 and specially FOT30) cannot be reliably transformed to accommodate the spatial pattern and magnitude of their respective instantaneous versions, leading to inconsistent results when projected into the future. As a result, we advocate caution when using daily mean data and strongly recommend the application of the standard definition for its calculation as closely as possible. Threshold-dependent indices derived from FWI are not reliably represented by the daily mean version and thus can neither be applied for the estimation of future fire danger season length and severity, nor for the estimation of future extreme events. [ABSTRACT FROM AUTHOR]

Since several destructive floods have occurred in Germany in the last decades, it is of considerable interest and relevance ( e.g., when undertaking flood defense design) to take a closer look at the climatic factors driving the changes in flood hazard in Germany. Even if there also exist non-climatic factors controlling the flood hazard, the present paper demonstrates that climate change is one main driver responsible for the increasing number of floods. Increasing trends in temperature have been found to be ubiquitous in Germany, with impact on air humidity and changes in (intense) precipitation. Growing trends in flood prone circulation pattern and heavy precipitation are significant in many regions of Germany over a multi-decade interval and this can be translated into the rise of flood hazard and flood risk. [ABSTRACT FROM AUTHOR]