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This paper explores the determinants of carbon taxation by focusing on recent efforts to tax carbon in Washington State. The paper identifies citizen demand, energy interests, and tax structure as possible factors in the emergence of carbon taxation. Washington has relatively high demand for climate action, and is unique with respect to its high reliance on indirect taxation and its low level of local fossil fuel interests. I argue this context, especially the high reliance on indirect taxation, makes taxation more appealing than other carbon pricing alternatives. I then test whether local tax structure shapes preferences for carbon taxation using county level opinion data. I find evidence that support for carbon taxation is higher in states with higher gasoline taxes, but no effect from sales and sin taxes. I conclude summarizing various accounts of each initiative's failure, and highlight a few lessons from the efforts to tax carbon in Washington state. [ABSTRACT FROM AUTHOR]

The incidence of dry or wet day sequences has a great influence on crops management and development. The lack of spatialized observed data with appropriate temporal resolution to investigate the changes that has occurred during the last century regarding the length and frequencies of those sequences has led to reliance on reanalysis products. However, the question can be raised about the suitability of those products when evaluating such climate indices and their impacts on crop production. Different products are here investigated to evaluate how the succession of dry and wet days are depicted in Sweden. Results show that reanalysis product tends to overestimate the number of wet days and wet periods and underestimate dry periods. We also showed clearly that the frequency and intensity of dry and wet spells returned can differ widely between products. For instance, number of dry spell events can range from 1 to 11 over the same decade for two different products. This paper does not aim to classify the RPs regarding their goodness or efficiency but try to highlights the divergence between them in representation of spells which could generate substantial differences in climate impact analysis in agricultural modeling. [ABSTRACT FROM AUTHOR]

Understanding the historical and future spatio-temporal changes in climate extremes and their potential risk to rice production is crucial for achieving food security in Bangladesh. This paper presents results from a study on trend analysis for 13 climate metrics that significantly influence rice production. The analysis was conducted using the non-parametric Mann-Kendall test and the Theil-Sen slope estimator methods. The study included data from all available weather stations in Bangladesh and the assessment was done for both the wet (May to October) and dry (November to April) seasons, which cover the growing seasons of the country's three types of rice: Aus, Aman and Boro. Results show significant decreasing trends for wet season rainfall (>12 mm/season/year in some stations) in the central and north regions. In addition, dry season rainfall is decreasing significantly in many areas, whilst dry season dry spells are increasing throughout Bangladesh. Decrease in rainfall in some of these areas are of concern because of its impacts on rainfed Aus rice and in the sowing/planting of rainfed Aman rice and irrigated dry season Boro rice. The maximum temperatures in the wet season are increasing throughout the country at 0.5°C every ten years, significantly at most of the climate stations. The analysis shows that the number of days with temperature >36°C has significantly increased in 18 stations over the last three decades, which implies a serious risk to Aman rice yield. The current maximum temperatures (both in the wet and dry seasons) are higher than the optimum temperature ranges for rice production, and this will have likely adverse effects on yield in the face of climate change with increasing temperatures. The results herein have practical implications for planning appropriate adaptation policies to ensure food security in the country. [ABSTRACT FROM AUTHOR]

Climate change may pose an acute threat to humanity due to physical and biological constraints on regional habitability. A recent study proposed that the human climate niche is a narrow segment of the Earth's temperature range, with a mode of habitation around 13°C. Here, the human climate niche is recharacterized using a novel graphical technique, the size-intensity chart. Several measures of population distribution were compiled to test the idea that humans live preferentially in the temperate range (10-20°C) rather than the warm range (20-30°C). The temperate range has a higher average population density (people/ km2), which suggests that it is more suitable for humans than the warm range. However, other population measures suggest the opposite. The warm range has a greater overall population; and regions with high population densities cover a greater land area and are home to more people in the warm range. Population density also depends on annual precipitation R; size intensity charts show that population density increases sharply with precipitation for 40 < R < 80 cm/yr. The warm temperature range has a greater surface area with desert conditions of R < 10 cm/yr, but sparse habitation in dry regions does not explain the lower average population density of the warm range. Overall, human habitation patterns do not show a consistent preference for temperate over warm lands, and that precipitation may mediate, but not limit this relationship. [ABSTRACT FROM AUTHOR]

The 2015 Paris Agreement outlined the goal to limit temperature increases below 2°C, preferably to 1.5°C. In response, several countries have announced net-zero emission pledges (NZEP). The credibility of these pledges varies because countries have committed to different target years. Moreover, some pledges outline sectoral as opposed to economy-wide targets and vary in how they monitor progress. To assess the pledge's credibility, we create a novel NZEP stringency score. We find that climate leaders with a higher share of renewable energy in final energy consumption are more likely to have announced more stringent NZEPs. However, economic development, the size of the economy, countries' embeddedness in international environmental treaties, and the robustness of domestic civil society are not associated with NZEP stringency. [ABSTRACT FROM AUTHOR]

Detailed knowledge about the intra-urban air temperature variability within a city is crucial for the implementation of adaptation strategies to counteract the negative effects of urban heat stress. Various methods to model urban-rural temperature differences exist, but they often only cover certain periods (heatwave, hot day) or meteorological conditions (sunny and calm) due to computational limitations or limited data availability. Here, we present a land use regression approach to model nocturnal air temperature fields for every single night of the summers 2018 to 2020 in a city with complex terrain (Bern, Switzerland). Furthermore, we investigate the applicability of different model structures and straight-forward computable GIS variables to model cold air drainage, which exerts an important influence on the local-scale climate of cities with complex terrain. The geostatistical models are calibrated with in-situ data of a dense low cost air temperature measurement network and high resolution spatiotemporal (land use and meteorology) data, which are all publicly available. The resulting land use regression models are capable to model and map intra-urban air temperature differences with a good model performance (R²: 0.65-0.71; RMSE: 0.69-0.76 K). Evaluations with data from additional measurement stations and periods (summer 2021) show that the models are able to estimate different meteorological and spatial conditions, but that the representation of small-scale topographic features remains difficult. However, the comparatively low computational and financial effort needed to calculate nocturnal air temperature fields at daily basis enable new applications for cities with restricted resources for various areas of interest, such as urban planning (e.g. effect of heat mitigation policies) or heat risk management (e.g. analyze small-scale urban heat vulnerability). [ABSTRACT FROM AUTHOR]

Climate-Smart Agricultural (CSA) practices are crucial in managing climatic shocks faced by smallholder farmers in sub-Saharan Africa. However, evidence on the socio-psychological drivers of farmers' adoption of CSA practices remains limited. This study employed the Theory of Planned Behavior framework to analyze smallholder farmers' intention and adoption behavior toward CSA practices in rural Ghana. The study sampled 350 smallholder farmers from the Upper East and North-East Regions of Ghana and employed the Structural Equation Model to understand smallholder farmers' intention and adoption behavior toward CSA practices. Results showed that farmers' attitudes (notably their beneficial evaluation of CSA practices) had a significant impact (0.25) on their intention to adopt CSA practices. Social pressure exerted on farmers to use CSA practices (Subjective norm) also had a significant impact (0.52) on farmers' adoption behavior. Perceived behavior control which measures the controllability and use of CSA practices also had a significant impact on both the intention (0.43) and adoption behavior (0.20) of smallholder farmers. Findings highlight the role socio-psychological factors play in explaining the adoption of CSA practices in rural Ghana. We recommend the need to create awareness of CSA practices by sharing relevant information more widely on CSA practices through community leaders, chief farmers, assembly members, and clan heads in order to exert influence on farmer's adoption of CSA practices. [ABSTRACT FROM AUTHOR]

We present a survey of the French research community and climate change carried out in 2020. It is one of the largest surveys ever conducted on this issue: it is based on a sample of more than 6,000 respondents representative of the French public sector research community, regardless of their status and discipline. On the one hand, it measures practices that emit large amounts of greenhouse gases, such as air travel, and addresses the differences between disciplines and within them according to different individual characteristics (gender, status, location, etc.). On the other hand, it questions the representations of research actors concerning the climate emergency, and what they are willing to do to reduce their emissions. The survey highlights three results: first, an acute awareness of environmental and climate issues widely shared by members of the scientific community; second, a willingness to implement changes; and third, a clear gap between these attitudes and practices that still emit large amounts of greenhouse gases. This raises the question of the role of research institutions, whose support is required to implement profound reforms in the organization of research activities. [ABSTRACT FROM AUTHOR]

Vegetation is subject to multiple pressures in the 21st century, including changes in climate, atmospheric composition and human land-use. Changes in vegetation type, structure, and function also feed back to the climate through their impact on the surface-atmosphere fluxes of carbon and water. Dynamic Global Vegetation Models (DGVMs), are therefore key component of the latest Earth System Models (ESMs). Model projections for the future land carbon sink still span a wide range, in part due to the difficulty of representing complex ecosystem and biogeochemical processes at large scales (i.e. grid lengths ≈ 100km). The challenge for developers of DGVMs is therefore to find an optimal balance between detailed process representation and the ability to scale-up. We categorise DGVMs into four groups; Individual, Average Area, Two Dimensional Cohort and One Dimensional Cohort models. From this we review popular methods used to represent dynamic vegetation within the context of Earth System modelling. We argue that the minimum level of complexity required to effectively model changes in carbon storage under changing climate and disturbance regimes, requires a representation of tree size distributions within forests. Furthermore, we find that observed size distributions are consistent with Demographic Equilibrium Theory, suggesting that One Dimensional Cohort models with a focus on tree size, offer the best balance between computational tractability and realism for ESM applications. [ABSTRACT FROM AUTHOR]

The number of people in food crisis around the world is increasing, exacerbated by COVID-19, conflict, and climate change. Major crop yields are projected to decrease in low-latitude regions, making tropical and sub-tropical food systems particularly vulnerable. Increased cultivation of breadfruit (Artocarpus altilis), a neglected and underutilized species (NUS), has the potential to enhance climate resilience and overall sustainability of low-latitude agricultural systems. To better understand breadfruit's cultivation suitability and geographic range in current and future climates, we use breadfruit presence data collected from previous studies and a global citizen science database, and a selection of bioclimactic variables, to build an ensemble of 6 species distribution models that delineate the current climatically viable breadfruit range. We then assess the climatically viable future breadfruit range (2061-2080) under stabilization and high emission scenarios using an ensemble of 8 global circulation model (GCM) projections. The area of suitable breadfruit range within the global tropics and subtropics is projected to decrease ~4.4% in the stabilization scenario and ~4.5% in the high emission scenario. In Southeast Asia and the Pacific Islands, yield quality and consistency show minimal decreases under the high emission scenario, with increases in total suitable area under both. In contrast, in Latin America and the Caribbean, the current suitable breadfruit range is projected to contract ~10.1-11.5% (stabilization-high emission). Present and future model suitability outputs suggest opportunities to successfully expand breadfruit cultivation over the next decades in sub-Saharan Africa, where food insecurity is coincidentally high. However, in all regions, high emission scenario conditions reduce the overall consistency and quality of breadfruit yields compared to the stabilization scenario. Our results have the potential to inform global food security adaptation planning, highlighting breadfruit as an ideal NUS to incorporate in food security adaptation strategies. [ABSTRACT FROM AUTHOR]

Mobile bottom fishing using trawls and dredges may cause significant reductions in seabed sediment organic carbon stores, limiting the oceanic carbon sink. Although uncertainties remain about the fate of disturbed carbon, protecting the most important and highly disturbed seabed carbon sinks for climate change mitigation represents a sensible precautionary policy. Using spatial modelling of best available datasets relating to seabed carbon stocks and fishing disturbance in the UK Exclusive Economic Zone (EEZ), we estimate the cumulative disturbance of organic carbon by mobile bottom fishing to be 109 Mt per year. Areas with high carbon stocks and disturbance are geographically restricted enabling identification of potential priority areas for precautionary carbon management and/or future research. By targeting areas with the highest 1%, 5% and 10% of carbon values, while also accounting for fisheries displacement, we examined three management levels ranging from 3-12% of the area of the EEZ. These areas encompass between 7-29% of organic carbon stocks. If all mobile bottom fishing disturbance in priority areas was eliminated it would reduce seabed carbon disturbance across the EEZ by 27-67%. Eliminating this fishing effort would be estimated to affect fisheries landings worth between £55m and £212m per year. In contrast, if all mobile bottom fishing was displaced from priority areas to other areas within the study region, our modelling predicts net reductions of organic carbon disturbance between 11% and 22%. Further research is needed to quantify how much of this carbon is remineralised following disturbance and therefore the magnitude of carbon emissions/savings. We also find that to offset the carbon and financial impacts of fisheries displacement, complementary management will be necessary to protect more carbon, including gear modifications to reduce seabed disturbance, overall effort reductions, and incentives to switch to alternative fishing methods. [ABSTRACT FROM AUTHOR]

The Galaápagos Islands play host to an iconic ecosystem--a UNESCO World Heritage Site and the second largest marine reserve in the world, home to several endangered species. The waters off the west coast of the Galaápagos are also one of the few places in the world ocean that are presently cooling, with potentially significant ecological consequences of this local reprieve from global warming. Here I show, using a recently developed high-resolution ocean state estimate, that the observed cooling in the Galápagos is the result of a strengthening of the wind-driven equatorial ocean circulation. An acceleration and shift of the Equatorial Undercurrent, which can be attributed to a strengthening of the cross-equatorial component of the trade wind in response to the interhemispheric gradient in surface warming, leads to a 54% increase in upwelling velocity along the western Galápagos Islands as well as increased shear-induced mixing. Analogous to other so-called "cold blobs," such as the one south of Greenland in the North Atlantic, this is an early and important sentinel of a broader change in the tropical ocean circulation. Thus far, and for perhaps the very near future, the western shores of the Galápagos appear to offer refuge from some of the deleterious impacts of anthropogenic climate change including suppressed upwelling and surface warming. [ABSTRACT FROM AUTHOR]

The Andean-Amazon foothills region, one of the richest biodiversity ecoregions on earth, is threatened by climate change combined with unsustainable agricultural and extensive livestock farming. These land-use practices tend to reduce the diversification of rural farming, decreasing households' livelihood alternatives and rendering them more vulnerable to climate change. We studied the relationship between rural livelihood diversification and household-level vulnerability to climate change in a sample of Andean-Amazon foothills households in Colombia and Peru. Firstly, we determined typologies of households based on their rural livelihood diversification, including farming diversification (agrobiodiversity and farming activities) and agroecological management practices. Secondly, we evaluated each household typology's vulnerability to climate change by assessing sensitivity and adaptive capacity based on the 'livelihood assets pentagon', which encompasses the five human capitals: natural, social, human, physical, and financial. We concluded that households with higher rural livelihood diversification are less vulnerable to climate change. However, it is impossible to draw significant conclusions about the relationship between the factors of diversification of management practices and vulnerability to climate change because most households have few agroecological practices. Results may inform future interventions that aim to decrease Andean-Amazon foothills households' sensitivity and strengthen their adaptive capacity to climate change. [ABSTRACT FROM AUTHOR]

Long-term monitoring of the spring and autumn phenology of five animal species, four plant species, phytoplankton communities, lake temperatures and ice cover on the Paul Smith's College Phenology Trail in the uplands of the Adirondack State Park (NY, USA) has produced time series spanning 1990-2020 for the biological and water temperature records and 1909-2020 for lake ice. In conjunction with climate records from three nearby weather stations these observations demonstrate that the ice on Lower Saint Regis Lake now thaws one week earlier, on average, than it did in 1909 while the region as a whole warmed by 1.7°C and received 19 cm more precipitation annually. Statistically significant warming trends between 1990 and 2020 were restricted to July and September and therefore contributed to a scarcity of temporal shifts in the spring phenologies of species and lake ice during that shorter time frame, but the lake surface warmed by 1.9°C on average in October. Although most of the phenological records displayed no statistically significant directional change within the 1990-2020 time interval they revealed strong correlations between phenology and monthly air temperatures that are of predictive value. Together with projections from regionally down-scaled climate models these relationships suggest that the phenologies of the species and ice dynamics in question could shift by ca. 1-3 weeks by 2100 depending on the analytical approach used and the magnitude of fossil fuel emissions during this century. As Adirondack winters become shorter and milder before potentially losing snow and ice altogether over the longer term, the unique cultural ecology of the region's human residents will face profound existential challenges along with the ecosystems and species around them. [ABSTRACT FROM AUTHOR]

International financial support for climate adaptation is expected to double by 2025. As adaptation finance expands, however, concern is growing that it is failing to benefit those most vulnerable to negative climate impacts. Qualitative studies have demonstrated how entrenched forms of inequality, such as patronage, can enable elite capture of international resources and prevent benefits from reaching relatively vulnerable households within communities. This study contributes to the literature on power in adaptation and climate finance by quantitatively analyzing the distributional outcomes of a UN Adaptation Fund project in the Aloatra-Mangoro region of Madagascar. We employ mixed-methods to examine how informal mechanisms of patronage influenced the distribution of project benefits. Using a multi-level model to analyze 599 household surveys, we compare the political connectivity of beneficiary and non-beneficiary households. We find that households that participated had higher levels of political connectivity than those that did not. This finding is robust across three different measures of participation and is reinforced by qualitative findings from formal and informal interviews. We conclude that rather than targeting the most vulnerable, the project likely disproportionately benefited households already better positioned to adapt and exacerbated inequality within targeted communities. By unpacking how household-level political power shaped access to benefits, this study advances discussion on rethinking approaches to power and inequality in internationally financed adaptation. [ABSTRACT FROM AUTHOR]

With increasing urgency of local and regional climate adaptation, there is a growing need for governments to identify and respond effectively to the concerns of communities they serve and to align investments. We designed and piloted a novel hyperlocal method for urban adaptation planning combining two social science tools that have been widely but separately used to foster community engagement and strategize solutions. Our not-for-profit community partners facilitated multi-session online workshops with participants from two communities in South Florida with whom they have well-established relationships and in which socioeconomic conditions and climate risks represent notable vulnerabilities. The workshops first employed photovoice to elicit individual narratives about climate change impacts; participants then followed a design thinking protocol to critically evaluate the leading concerns they identified and propose adaptation solutions. Geospatial mapping and data tools were provided for participants to gain additional tools and further knowledge. Local planning and resilience officials attended some or all of the workshops as observers and interlocutors, dialoguing with participants. Comparative analysis revealed differences in risk awareness and primary concerns between communities, and further demonstrated that concerns and solutions proposed by members of at-risk neighborhoods do not always align with geospatial data that often drives infrastructure adaptation planning in the region, suggesting that more widespread use of community engaged methods could enhance government climate adaptation responses for local communities. [ABSTRACT FROM AUTHOR]

Climate issues widely feature in policy discussions, but it is not clear if voters reward politicians who champion climate policies. In some countries, candidates and parties with an explicit climate agenda have done well in elections (Switzerland and Germany being recent examples) while in other cases, voters have either ignored climate issues or punished candidates/parties for their climate positions (Australia, the U.K., and Canada). Focusing on the U.S. as a case study, we examine the electoral appeal of the Green New Deal (GND) legislative proposal which outlined a vision for a sustainable and equitable economy. Different versions of the GND policy idea have been adopted across the world. The GND was introduced in the US Congress in 2019 and was endorsed by 102 of the 232 House Democrats, but not by a single Republican. Our analysis finds an association between Democrats' endorsement of the GND and a 2.01 percentage point increase in their vote share, even after controlling for the 2018 vote share. Unlike most western democracies, the U.S. is a laggard on climate issues. Yet, we find that U.S. voters reward legislators who advocate an ambitious climate policy agenda. [ABSTRACT FROM AUTHOR]

This study estimated the effect of changes in the amount of precipitation associated with climate change on pluvial flood damage and the effectiveness of mitigation and adaptation measures throughout Japan. First, the cost of damage caused by pluvial flooding was calculated based on extreme rainfall, assuming a situation in which river levels are high, and rainwater does not drain into the rivers. Additionally, extreme rainfall in future climates was estimated from the output values of five general circulation models. Then, using these figures for extreme rainfall, the cost of pluvial flood damage in future climates was estimated. Improving the maintenance level of inland water drainage facilities and converting buildings to a piloti design were selected as adaptation measures. The results showed that in the Representative Concentration Pathway (RCP) 8.5 scenario, the expected annual damage cost (EADC) in the late 21st-century climate (2081-2100) scenario increases to approximately 2.3 times that of the baseline climate (1981-2000). If climate change is mitigated to RCP 2.6, the EADC in the late 21st-century climate scenario is estimated to be reduced by 28% compared to the EADC in the RCP 8.5 scenario. It is also estimated that the EADC in future climates could be kept lower than in the baseline climate by taking multiple rather than single measures. However, in the RCP 8.5 scenario for the late 21st-century climate, even if multiple adaptation measures are taken, the EADC was estimated to increase by 9% compared to the EADC in the baseline climate. [ABSTRACT FROM AUTHOR]

Climate reconstructions have contributed tremendously to our understanding of changes in the climate system and will continue to do so. However, in climate science the focus has partly shifted away from past seasonal and annual mean climate towards weather variability and extreme events. Weather events are more directly relevant for climate impacts and they capture the scale at which important processes take place. Weather reconstructions therefore help to better understand atmospheric processes, particularly during extreme events, to assess decadal-to-multidecadal climate variability through the lens of weather changes, and they allow impact modelling of past events. Consequently, attempts are currently undertaken to extend weather data sets far back into the past. In this review I discuss methods of weather reconstructions that are in use today. The methods range from expert analyses to data assimilation, from analog approaches to machine learning. Products range from weather types to four-dimensional fields. The methods complement each other as they are based on different assumptions and are based on different data sets. Weather reconstructions require more meteorological data than climate reconstructions. Additional data rescue efforts are therefore needed. [ABSTRACT FROM AUTHOR]

Around the world, most people are aware of the problem of climate change, believe it is anthropogenic, and feel concerned about its potential consequences. What they think should be done about the problem, however, is less clear. Particularly due to widespread support among policy experts for putting a price on greenhouse gas emissions, more studies have investigated public attitudes towards carbon taxes than any other type of policy. Such studies have found substantial public opposition to carbon taxes, largely due to political distrust, though also some evidence that careful design and messaging can mitigate people's skepticism. Surprisingly few studies have investigated attitudes towards other climate policies, and there is an urgent need for more research about what--given their beliefs about the nature and severity of the problem--people would like to see their governments doing. This is especially the case for residents of lower-income and/or non-Western nations. [ABSTRACT FROM AUTHOR]

In this study, we aimed to understand how restaurants can contribute to climate change mitigation via menu design. We investigated two types of interventions: changing the configuration of menu entries with variable side dishes so that the most climate-friendly option is set as the default and indicating the greenhouse gas emission of each dish via carbon labels. In an online simulation experiment, 265 participants were shown the menus of nine different restaurants and had to choose exactly one dish per menu. In six menus, the main dishes were presented with different default options: the side dish was associated either with the highest or with the lowest greenhouse gas emissions. The other three menus consisted of unitary dishes for which the default rules did not apply. All menus were presented either with or without carbon labels for each dish option. The results indicated that more climate-friendly dish choices resulting in lower greenhouse gas emissions were made with the low-emission than the high-emission default condition, and when carbon labels were present rather than absent. The effects of both interventions interacted, which indicates that the interventions partly overlap with regard to cognitive predecessors of choice behavior, such as attentional focus and social norms. The results suggest that the design of restaurant menus has a considerable effect on the carbon footprint of dining. [ABSTRACT FROM AUTHOR]

This study demonstrates how a comprehensive knowledge base can be used by the aquaculture industry, researchers, and policymakers as a foundation for more targeted and detailed climate change impact analysis, risk assessments and adaptation planning. Atlantic salmon (Salmo salar) production in Norway was used as a case study and to illustrate the need to consider impacts from multiple stressors across different production stages and the wider supply chain. Based on literature searches and industry news, a total of 45 impacts and 101 adaptation responses were identified. Almost all impacts were linked to multiple climate stressors, and many adaptation responses can be used for a range of impacts. Based on the research, a move towards more targeted and detailed assessments is recommended. This can be facilitated through a strong knowledge base, further research to address complexities, and better communication between all stakeholders. The results also demonstrate the need for more climate change research that reflects the challenges that the aquaculture sector faces, where multiple stressors and the range of impacts across production stages and the wider supply chain are included. Highlighting the wide range of stressors, impacts and adaptation responses provides a more holistic understanding of the real-world complexities that aquaculture producers face. This again could facilitate adoption of more effective responses to climate change needed to maintain or increase production sustainably. [ABSTRACT FROM AUTHOR]

"It is now well established that the influence of anthropogenic climate change on certain individual extreme weather events can be quantified by event attribution techniques. It is time that these activities move from the research community to the operational centers. Such routine evaluation of the human influence on extreme weather increases our scientific understanding and informs the public of climate change impacts. Furthermore, quantification of the human influence on extreme weather can be used to fairly evaluate climate change induced loss and damages". [ABSTRACT FROM AUTHOR]

Animal agriculture contributes significantly to global warming through ongoing emissions of the potent greenhouse gases methane and nitrous oxide, and displacement of biomass carbon on the land used to support livestock. However, because estimates of the magnitude of the effect of ending animal agriculture often focus on only one factor, the full potential benefit of a more radical change remains underappreciated. Here we quantify the full "climate opportunity cost" of current global livestock production, by modeling the combined, long-term effects of emission reductions and biomass recovery that would be unlocked by a phaseout of animal agriculture. We show that, even in the absence of any other emission reductions, persistent drops in atmospheric methane and nitrous oxide levels, and slower carbon dioxide accumulation, following a phaseout of livestock production would, through the end of the century, have the same cumulative effect on the warming potential of the atmosphere as a 25 gigaton per year reduction in anthropogenic CO2 emissions, providing half of the net emission reductions necessary to limit warming to 2°C. The magnitude and rapidity of these potential effects should place the reduction or elimination of animal agriculture at the forefront of strategies for averting disastrous climate change. [ABSTRACT FROM AUTHOR]

To improve the robustness of projections of freshwater fish distributions under climate change, species distribution models (SDMs) were calculated for six fish species in southwestern Germany with different ecological requirements along an upstream-downstream gradient in a multi-general circulation model (GCM) approach. Using the maximum entropy (Maxent) algorithm and a high number of occurrence records (N = 4684), species distributions were projected to future climate conditions derived from 13 GCMs across the most likely representative carbon pathways (RCP4.5 and 8.5) and two time spans (near future 2050, and far future 2070), resulting in 104 distribution maps per species that were then used for the statistical analysis of future trends. Climate change is likely to affect the distribution of four of the six fish species. The potential ranges of salmonids are predicted to decline by up to 92% (brown trout) and 75% (grayling). In contrast, habitat suitability for perch and roach is predicted to increase by up to 108% and 53%, respectively. Even when accounting for broad variation in GCMs and realistic RCPs, these results suggest climate change will drive a significant redistribution of fish habitat. Salmonid-dominated communities in headwaters seem more sensitive to climate change than the fish communities of downstream sections. Because headwaters are a prevailing element of the hydrographic network in southwestern Germany, such changes may result in large-scale regressions of valuable fish communities that currently occupy broad geographic niches. [ABSTRACT FROM AUTHOR]

The future climate outlook was based on a combination of CCMs based on three Representative Concentration Pathway (RCP) scenarios including RCP 2.6, RCP 4.5 and RCP 8.5 for the future period of 2021-2051. The results showed an increase of the average Tmax in June, July and August (averaged by 1.8°C compared to the observed period) and a decrease in rainfall in May to September (averaged by 30.76 mm compared to the observed period under all three scenarios. Estimation of phenological stages of sesame under different scenarios showed that with increasing Tmax in April and May, the beginning of flowering, grain filling and physiological maturity was accelerated, also with increasing temperature from June to August the duration of the phenological stages was decreased. The effect of deficit irrigation (DI, supplying of 50% plant water requirement) on sesame phenological stages was not significantly different from full irrigation (FI). Simulation of canopy cover evolution (CC) and dry matter accumulation using the AquaCrop model revealed that the length of the late-season and the mid-season stages, have the greatest liability to be changed under the future climate change. Under the studied scenarios, the beginning of sesame growing season will accelerate from 9 to 11 days, which makes possible delayed sowing of sesame. The average of biomass (B) produced under three scenarios in DI and FI conditions were 17920 and 17241 kg ha-1, and the average of grain yield (GY) was 2905 and 3429 kg ha-1, respectively, which shows an increase by 31.5% and 28.7% of B, 18.4% and 39.5% of GY, compared to the observations (year 2016). The results revealed that under the future climate (except for RCP8 scenario), DI strategy can be used without reducing the GY of sesame due to the very little reduction (1.2%) in GY under DI compared to FI. [ABSTRACT FROM AUTHOR]