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Africa is projected to experience diverse and severe impacts of climate change. The need to adapt is increasingly recognized, from the community level to regional and national governments to the donor community, yet adaptation faces many constraints, particularly in low income settings. This study documents and examines the challenges facing adaptation in Africa, drawing upon semi-structured interviews (n = 337) with stakeholders including high-level stakeholders, continent-wide and across scales: in national government and UN agencies, academia, donors, non-governmental organizations, farmers and extension officers. Four key concerns about adaptation emerge: i) Climate data, scenarios and impacts models are insufficient for supporting adaptation, particularly as they relate to food systems and rural livelihoods; ii) The adaptation response to-date has been limited, fragmented, divorced from national planning processes, and with limited engagement with local expertise; iii) Adaptation policies and programs are too narrowly focused on explicit responses to climate change rather than responses to climate variability or broader development issues; and iv) Adaptation finance is insufficient, and procedures for accessing it present challenges to governments capacities. As a response to these concerns, we propose the 4-Cs framework which places adaptation for Africa at the center of climate projections, climate education, climate governance and climate finance, with corresponding responsibilities for government and non-government actors.

Transformational adaptation is increasingly viewed as necessary to prevent the worst offsets in development gains due to severe climate impacts. However, clarity regarding how to produce transformational adaptation in practice is lacking, creating problems for project design and implementation. This paper examines (1) how transformational adaptation has been defined by major funders of adaptation; (2) how the concept has influenced funding priorities and the financing of projects. The study is based on a comparative analysis of the investment criteria, board meeting minutes, documents, and reports of the primary financial mechanisms under the United Nations Framework Convention on Climate Change: the Least Developed Country Fund, the Special Climate Change Fund, the Adaptation Fund and the Green Climate Fund. Our study demonstrates an increasing emphasis on transformational adaptation across funds over time, particularly in the Green Climate Fund. Transformative potential does guide funding decisions, but a clear understanding of whether transformational change is achievable, feasible, and desirable under all conditions has not yet emerged, an issue acknowledged by the funds and regularly discussed. Our analysis suggests that acknowledging tensions which arise with transformation in adaptation finance is critical because investment criteria and definitions of transformation impact the approaches to adaptation countries take.

Multiple cropping systems provide more harvest security for farmers, allow for crop intensification and furthermore influence ground cover, soil erosion, albedo, soil chemical properties, pest infestation and the carbon sequestration potential. We identify the traditional sequential cropping systems in ten sub-Saharan African countries from a survey dataset of more than 8600 households. We find that at least one sequential cropping system is traditionally used in 35% of all administrative units in the dataset, mainly including maize or groundnuts. We compare six different management scenarios and test their susceptibility as adaptation measure to climate change using the dynamic global vegetation model for managed land LPJmL. Aggregated mean crop yields in sub-Saharan Africa decrease by 6–24% due to climate change depending on the climate scenario and the management strategy. As an exception, some traditional sequential cropping systems in Kenya and South Africa gain by at least 25%. The crop yield decrease is typically weakest in sequential cropping systems and if farmers adapt the sowing date to changing climatic conditions. Crop calorific yields in single cropping systems only reach 40–55% of crop calorific yields obtained in sequential cropping systems at the end of the 21st century. The farmers’ choice of adequate crops, cropping systems and sowing dates can be an important adaptation strategy to climate change and these management options should be considered in climate change impact studies on agriculture.

This study predicts the impact of climate change on African agriculture. We use a generalized linear model (GLM) framework to estimate the relationship between the proportion of various Agro-Ecological Zones (AEZs) in a district and climate. Using three climate scenarios, we project how climate change will cause AEZs to shift, causing changes in acreage and net revenue per hectare of cropland. Our results predict that Africa will suffer heavy annual welfare losses by 2070–2100, ranging between US$14 billion and US$70 billion, depending on the climate scenario and cropland measure considered.

Water scarcity is popularly associated with inter-state conflict, yet the academic literature also touts scarcity as an important variable for understanding cooperation over international freshwater. Building on studies that consider the relationship between scarcity and hydro-political cooperation, this paper empirically investigates why water treaties are negotiated for some rivers and between some riparians, and not others. Rather than considering a linear relationship between scarcity and cooperation, this study hypothesizes a curvilinear relationship expecting agreements to emerge in situations where scarcity is moderate rather than very low or high. Additional variables considered for understanding treaty formation include level of governance among the riparian states, prevailing power dynamics along the river, overall inter-riparian relations (measured by trade, diplomatic ties, and militarized disputes), and the geographical configuration of the entire river. The hypothesized curvilinear relationship between water scarcity and cooperation finds significant support in the empirical analyses. Governance, diplomatic relations, and trade are likewise found to be salient in explaining the levels of cooperation. The geographical configuration of the river was significant in only part of the estimates, and the militarized disputes variable was found to be insignificant across all models. Finally, while results confirm that cooperation may not depend on power asymmetries within riparian dyads, as suggested by some theories, the paper does find support for the contention that more developed states are in a position to provide incentives, such as financial transfers, to less-developed states so as to facilitate an international agreement.

Although there is now an extensive literature on the economic impacts of climate change on agriculture, no study has yet addressed the endogeneity of irrigation. This paper examines how climate affects the choice to irrigate and the conditional income earned by each farmer. The paper develops a selection model of irrigation choice and conditional income. Using data from farmers across eleven African countries, the paper demonstrates that the choice of irrigation is sensitive to both temperature and precipitation. Rainfed and irrigated farm income also both respond to climate but have different climate sensitivity. Impact models that fail to account for endogenous irrigation are biased.

This study measured the economic impacts of climate change on crop and livestock farming in Africa based on a cross-sectional survey of over 8000 farming households from 11 countries in east, west, north and southern Africa. The response of net revenue from crop and livestock agriculture across various farm types and systems in Africa to changes in climate normals (i.e. mean rainfall and temperature) is analysed. The analyses controlled for effects of key socioeconomic, technology, soil and hydrological factors influencing agricultural production. Results show that net farm revenues are in general negatively affected by warmer and drier climates. The small-scale mixed crop and livestock system predominantly typical in Africa is the most tolerant whereas specialized crop production is the most vulnerable to warming and lower rainfall. These results have important policy implications, especially for the suitability of the increasing tendency toward large-scale mono-cropping strategies for agricultural development in Africa and other parts of the developing world in light of expected climate changes. Mixed crop and livestock farming and irrigation offered better adaptation options for farmers against further warming and drying predicted under various future climate scenarios.

Surveys for more than 9,500 households were conducted in the growing seasons 2002/2003 or 2003/2004 in eleven African countries: Burkina Faso, Cameroon, Ghana, Niger and Senegal in western Africa; Egypt in northern Africa; Ethiopia and Kenya in eastern Africa; South Africa, Zambia and Zimbabwe in southern Africa. Households were chosen randomly in districts that are representative for key agro-climatic zones and farming systems. The data set specifies farming systems characteristics that can help inform about the importance of each system for a country’s agricultural production and its ability to cope with short- and long-term climate changes or extreme weather events. Further it informs about the location of smallholders and vulnerable systems and permits benchmarking agricultural systems characteristics.

This paper focuses on empirically assessing determinants of river basin management decentralization, which is growing in popularity among water resource managers world wide. Measuring decentralization as a shift of decision-making responsibility to water users or governments at the river basin level or below, the analysis sheds light on the decentralization reform process and its success, using primary data from 83 river basins world wide. Contrary to common perception that primarily emergency situations trigger reform, persistent water scarcity is found to be a major stimulus to reform. Similarly, financially well-endowed or -developed basins do not necessarily outperform poor and underdeveloped basins. Conditions improving decentralization performance include: existence of dispute resolution mechanisms; greater financial responsibility of users; and as opposed to traditional thinking, government financial support to basin budget.

This paper measures the influence of climate normals (average long-term surface wetness and temperature) and interannual climate variance on farms in the United States and Brazil using satellite data. The paper finds that just climate normals or just climate variance variables can explain both net revenues and how much land is used for cropland. However, because they are correlated with each other, it is important to include both normals and variance in the same statistical model to get accurate measures of their individual contribution to farm outcomes. In general, higher climate variance increases the probability that land is used for cropland in both countries and higher temperatures reduce both cropland and land values. Other annual effects were not consistent across the two countries.

This paper compares how well satellite versus weather station measurements of climate predict agricultural performance in Brazil, India, and the United States. Although weather stations give accurate measures of ground conditions, they entail sporadic observations that require interpolation where observations are missing. In contrast, satellites have trouble measuring some ground phenomenon such as precipitation but they provide complete spatial coverage of various parameters over a landscape. The satellite temperature measurements slightly outperform the interpolated ground station data but the precipitation ground measurements generally outperform the satellite surface wetness index. In India, the surface wetness index outperforms station precipitation but this may be reflecting irrigation, not climate. The results suggest that satellites provide promising measures of temperature but that ground station data may still be preferred for measuring precipitation in rural settings.

This paper tests whether climate has an impact on per capita rural income. The study finds that total (agricultural and nonagricultural) income in rural counties and municipios in the US and Brazil are affected by climate. The study demonstrates that this income effect is due to changes in the net value of agriculture. Regions with better climates for agriculture support higher rural incomes and regions with poor climates have more rural poverty. The results also suggest that global warming will likely increase rural poverty.

This paper examines the impact of climate change on the net revenue (NR) of farmers from Bangladesh, Indonesia, Sri Lanka, Thailand and Vietnam. Two Ricardian models are estimated: (1) a traditional Ricardian model of the impact of climate change on annual farm NR and (2) a structural Ricardian model that first estimates the number of growing seasons and then the net revenue per season. The traditional model reveals annual NR is sensitive to autumn and summer climate variables. The seasonal effects offset each other so that uniform marginal effects are insignificant. Future climate scenarios likely harm Sri Lanka but could either benefit or harm Indonesia depending on the climate scenario. The structural Ricardian model suggests climate change will reduce the net revenue of three-season farms and increase the revenue of one-season farms causing farmers to switch from three-season farming to one-season farming. Expected losses by 2100 for the region range from [Formula: see text]10% to [Formula: see text]18%. Impacts in Indonesia may be higher ranging from [Formula: see text]20% to [Formula: see text]28%.

A survey of farmers in Bangladesh, Indonesia, Sri Lanka, Thailand, and Vietnam reveals that farmers are keenly aware of even slight changes in their climate. Over 90% of the farmers interviewed perceived small changes in temperature or precipitation patterns where they lived. Over half claimed to have changed their irrigation, timing, or crop choices because of climate change. Although the link between perceived changes and stated adaptations is weak, farmers are aware of the types of changes they need to make in response to climate change in South-East Asia. Adaptation responses must be firmly grounded in not only local conditions, but also the views of participants at the front lines of climate change impacts. The knowledge base of farmers grappling with the challenges of climate change must be taken into account when policy responses to support adaptation are formulated.

This special issue examines the impact of climate on agriculture as well as the economics of farmer adaptation in South-East Asia. An extensive survey was undertaken of small farmers in Bangladesh, Indonesia, Mongolia, Sri Lanka, Thailand and Vietnam. Ricardian studies were undertaken to measure the likely impact of climate change on these farmers. Adaptation studies were undertaken to measure how farmers would likely change their behavior (choices) as climate changed. Perceptions were asked to gauge farmer awareness of climate change and their plans to adapt. The overall study provides many useful analyses into the climate sensitivity of agriculture in the region as well as how farmers might adapt to climate changes.

Bangladesh, Sri Lanka, Thailand, and Vietnam each conducted a Ricardian analysis of crop net revenue (NR) in their country. The countries defined seasons slightly differently depending on their monsoon and dry periods. They also sometimes included slightly different variables in their regressions. The countries are small so that the climate results are often insignificant. However, the Ricardian model does predict near term damage in Bangladesh in the CanESM climate scenario and near and far term damage in Thailand in the CMCC climate scenario.

This study finds that South-East Asian farming is sensitive to climate change. Traditional Ricardian studies at the country and regional levels reveal that net revenue is affected by seasonal climate. A structural Ricardian model of growing season choice reveals climate change will reduce net revenues in the near term by 4–8% and in the long term by 10–18%. The implications of this impact on key sustainable development goals such as poverty reduction is likely to be profound. The study finds that farmers who rely on cultivating in three seasons will be especially hard hit by climate change relative to those that rely only on a single season. The results indicate that farmers will switch from 3 seasons to 1 season per year and reduce some of the losses that they would otherwise sustain. An analysis of crop adaptation finds that farmers will also adjust irrigation, crop choice, and the timing of planting in response to climate change. The livestock adaptation study finds that farmers will move towards livestock as climate warms. Farmers will also shift their choice of species away from large animals and move towards small animals. An analysis of perceptions finds that farmers throughout the region are aware that temperature is rising and they generally perceive that precipitation is falling. Half of the farmers interviewed have begun to take measures such as those reported in this study to adapt to climate change. The overall results suggest that acting on their self-interest, the agriculture sector will undertake a great deal of adaptation on its own. However, measures taken by the government such as providing up-to-date weather reports, extension, irrigation and assistance with new varieties can also be effective.

This paper assesses the impact of water supply variability on treaty cooperation between international bilateral river basin riparian states. Climate change is anticipated to change the variability of water supply, as well as its expected magnitude. Previous studies have focused mainly on water scarcity, measured in terms of mean precipitation or per capita water availability in the country, as a trigger for conflict or cooperation. The water variability measure used here captures both annual runoff variability and precipitation variability over periods of 30 and 100 years. The analysis used economic and international relations data to identify incentives for international cooperation in addressing water supply variability. The authors find that small-to-moderate increases in variability create an impetus for cooperation, although large increases in variability would reduce incentives for treaty cooperation. Stronger diplomatic and trade relations support cooperation, while uneven economic power inhibits cooperation. Various measures of democracy/governance suggest different impacts on cooperation across the basin riparians. The findings have policy implications in the context of preparedness for impacts of climate change on the water sector.

Elevated world temperatures, as forecasted by the 4th IPCC report, are expected to increase the hydrological cycle activity, leading to a change in precipitation patterns and increase in evapotranspiration. These in turn are expected to affect river runoff and water variability, depending on basin latitude. In this paper, we assess the impact of water supply variability on ‘treaty cooperation’ (defined here as the likelihood of treaty formation and number of treaties formed) between international bilateral river basin riparian states. The water variability measure that we use captures both annual runoff variability and precipitation variability. We employ additional control variables adopted from economic and international relations theories on international cooperation. The main results suggest that water supply variability in international bilateral basins creates an impetus for cooperation. Our results support an inverted U-shaped relationship between water supply variability and treaty cooperation. Similarly, interactions between the states in the form of diplomatic and trade relations support cooperation. Various measures of democracy/governance suggest different impacts on cooperation. Uneven economic power between the riparian states inhibits treaty cooperation. The geography variables we use are insignificant in all the estimated relationships.

This paper examines African livestock management across Agro-Ecological Zones (AEZs) to learn how they would adapt to climate change in the coming century. We analyze farm level decisions to own livestock and to choose a primary livestock species using logit models with and without country fixed effects or AEZ fixed effects. With a hot dry scenario, the results indicate that livestock ownership will increase slightly across all of Africa, but especially in West Africa and high elevation AEZs. Dairy cattle will decrease in semi-arid regions, sheep will increase in lowlands, and rearing chickens will increase at high elevations. On the other hand, if climate becomes wetter, livestock ownership will fall dramatically in lowlands and high elevation moist AEZs. Beef cattle will increase and sheep will fall in dry AEZs, dairy cattle will fall precipitously and goats will rise in moist AEZs, and chickens will increase at high elevations but fall at mid elevations. Therefore, adaptation measures should be tailored to a specific AEZ.

The study develops a new method to measure the impacts of climate change on agriculture called the Agro-Ecological Zone (AEZ) Model. A multinomial logit is estimated to predict the probability of each AEZ in each district. The average percentage of cropland and average crop net revenue are calculated for each AEZ. Then an estimate of the amount of cropland in Africa and where it is located is provided. Using current conditions, the model calculates baseline values of cropland and crop net revenue, and estimates the future impact of climate change using two scenarios-harsh and mild. Total cropland does not change much across the two climate scenarios. However, the predicted change in African crop revenue ranges from a loss of 14 percent in the mild climate scenario to 30 percent in the harsher climate scenario. The analysis reveals that the greatest harm from climate change is that it will shift farms from high to low productive AEZs. The approach not only identifies the aggregate impacts, but also indicates where the impacts occur across Africa. The central region of Africa is hurt the most, especially in the harsher climate scenario. The Agro-Ecological Zone Model is a promising new method for valuing the long-term impacts of climate change on agriculture.

This paper examines the distribution of climate change impacts across the six- teen Agro-Ecological Zones (AEZs) of Africa. We combine net revenue from livestock and

Using economic data from more than 8,500 household surveys across 10 African countries, this paper examines whether the choice of farm type depends on the climate and agro-ecological zone of each farm. The paper also studies how farm type choice varies across farmers in each zone, using a multinomial logit choice model. Farmers are observed to choose from one of the following five types of farms: rainfed crop-only, irrigated crop-only, mixed rainfed (crop and livestock), mixed irrigated, and livestock-only farming. The authors compare current decisions against future decisions as if the only change were climate change. They focus on two climate scenarios from existing climate models: the Canadian Climate Centre scenario, which is hot and dry, and the Parallel Climate Model scenario, which is mild and wet. The results indicate that the change in farm types varies dramatically by climate scenario but also by agro-ecological zone. Policy makers must be careful to encourage the appropriate suite of measures to promote the most adapted farm type to each location.

This paper quantifies how African farmers have adapted their crop and irrigation decisions to their farm's current agro-ecological zone. The results indicate that farmers carefully consider the climate and other conditions of their farm when making these choices. These results are then used to forecast how farmers might change their irrigation and crop choice decisions if climate changes. The model predicts African farmers would adopt irrigation more often under a very hot and dry climate scenario but less often with a mild and wet scenario. However, farms in the deserts, lowland humid forest, or mid elevation humid forest would reduce irrigation even in the very hot and dry climate scenario. Area under fruits and vegetables would increase Africa-wide with the very hot and dry climate scenario, except in the lowland semi-arid agro-ecological zone. Millet would increase overall under the mild and wet scenario, but decline substantially in the lowland dry savannah and lowland semi-arid agro-ecological zones. Maize would be chosen less often across all the agro-ecological zones under both climate scenarios. Wheat would decrease across Africa. The authors recommend that care must be taken to match adaptations to local conditions because the optimal adaptation would depend on the agro-ecological zone and the climate scenario.

This paper examines how farmers have adapted their livestock operation to the current climate in each agro-ecological zone in Africa. The authors examine how climate has affected the farmer's choice to raise livestock or not and the choice of animal species. To measure adaptation, the analysis regresses the farmer's choice on climate, soil, water flow, and socio-economic variables. The findings show that climate does in fact affect the farmer's decision about whether to raise livestock and the species. The paper also simulates how future climates may alter these decisions using forecasts from climate models and the estimated model. With a hot dry scenario, livestock ownership will increase slightly across all of Africa, but especially in West Africa and high elevation agro-ecological zones. Dairy cattle will decrease in semi-arid regions, sheep will increase in the lowlands, and chickens will increase at high elevations. With a mild and wet scenario, however, livestock adoption will fall dramatically in lowland and high latitude moist agro-ecological zones. Beef cattle will increase and sheep will fall in dry zones, dairy cattle will fall precipitously and goats will rise in moist zones, and chickens will increase at high elevations but fall at mid elevations. Livestock adaptations depend on the climate scenario and will vary across the landscape. Agro-ecological zones are a useful way to capture how these changes differ from place to place.

This paper examines the distribution of climate change impacts across the 16 agro-ecological zones in Africa using data from the Food and Agriculture Organization combined with economic survey data from a Global Environment Facility/World Bank project. Net revenue per hectare of cropland is regressed on a set of climate, soil, and socio-economic variables using different econometric specifications"with"and"without"country fixed effects. Country fixed effects slightly reduce predicted future climate related damage to agriculture. With a mild climate scenario, African farmers gain income from climate change; with a more severe scenario, they lose income. Some locations are more affected than others. The analysis of agro-ecological zones implies that the effects of climate change will vary across Africa. For example, currently productive areas such as dry/moist savannah are more vulnerable to climate change while currently less productive agricultural zones such as humid forest or sub-humid zones become more productive in the future. The agro-ecological zone classification can help explain the variation of impacts across the landscape.

This paper uses the Ricardian approach to examine how farmers in 11 countries in Africa have adapted to existing climatic conditions. It then estimates the effects of predicted changes in climate while accounting for whatever farmer adaptation might occur. This study differs from earlier ones by using farmers' own perceptions of the value of their land. Previous research, by contrast, has relied on either observed sale prices or net revenues, sometimes aggregated over geographically large tracts of terrain. The study also makes use of high resolution data describing soil quality and runoff. Furthermore, it tackles the challenges involved in modeling the effect of climate on agriculture in a study that includes countries in the northern and southern hemispheres, as well as the tropics. The study confirms that African agriculture is particularly vulnerable to climate change. Even with perfect adaptation, regional climate change by 2050 is predicted to entail production losses of 19.9 percent for Burkina Faso and 30.5 percent for Niger. By contrast, countries such as Ethiopia and South Africa are hardly affected at all, suffering productivity losses of only 1.3 percent and 3 percent, respectively. The study also confirms the importance of water supplies as measured by runoff, which, being affected by both temperature and precipitation, may itself be highly sensitive to climate change.

This paper examines whether the choice of crops is affected by climate in Africa. Using a multinomial logit model, the paper regresses crop choice on climate, soils, and other factors. The model is estimated using a sample of more than 7,000 farmers across 11 countries in Africa. The study finds that crop choice is very climate sensitive. For example, farmers select sorghum and maize-millet in the cooler regions of Africa; maize-beans, maize-groundnut, and maize in moderately warm regions' and cowpea, cowpea-sorghum, and millet-groundnut in hot regions. Further, farmers choose sorghum, and millet-groundnut when conditions are dry; cowpea, cowpea-sorghum, maize-millet, and maize when medium wet; and maize-beans and maize-groundnut when wet. As temperatures warm, farmers will shift toward more heat tolerant crops. Depending on whether precipitation increases or decreases, farmers will also shift toward drought tolerant or water loving crops, respectively. There are several policy relevant conclusions to draw from this study. First, farmers will adapt to climate change by switching crops. Second, global warming impact studies cannot assume crop choice is exogenous. Third, this study only examines choices across current crops. Future farmers may well have more choices. There is an important role for agronomic research in developing new varieties more suited for higher temperatures. Future farmers may have even better adaptation alternatives with an expanded set of crop choices specifically targeted at higher temperatures.

This study examines the impact of climate change on cropland in Africa. It is based on a survey of more than 9,000 farmers in 11 countries: Burkina Faso, Cameroon, Egypt, Ethiopia, Ghana, Kenya, Niger, Senegal, South Africa, Zambia, and Zimbabwe. The study uses a Ricardian cross-sectional approach in which net revenue is regressed on climate, water flow, soil, and economic variables. The results show that net revenues fall as precipitation falls or as temperatures warm across all the surveyed farms. In addition to examining all farms together, the study examined dryland and irrigated farms separately. Dryland farms are especially climate sensitive. Irrigated farms have a positive immediate response to warming because they are located in relatively cool parts of Africa. The study also examined some simple climate scenarios to see how Africa would respond to climate change. These uniform scenarios assume that only one aspect of climate changes and the change is uniform across all of Africa. In addition, the study examined three climate change scenarios from Atmospheric Oceanic General Circulation Models. These scenarios predicted changes in climate in each country over time. Not all countries are equally vulnerable to climate change. First, the climate scenarios predict different temperature and precipitation changes in each country. Second, it is also important whether a country is already hot and dry. Third, the extent to which farms are irrigated is also important.

Previous Ricardian analyses of agriculture have either omitted irrigation or treated irrigation as though it is exogenous. In practice, it is a choice by farmers that is sensitive to climate. This paper develops a choice model of irrigation in the context of a Ricardian model of cropland. The authors examine how climate affects the decision to use irrigation and then how climate affects the net revenues of dryland and irrigated land. This Ricardian 'selection' model, using a modified Heckman model, is then estimated across 8,400 farmers in Africa. The analysis explicitly models irrigation but controls for the endogeneity of irrigation. The authors find that the choice of irrigation is sensitive to both temperature and precipitation. Simulations of the welfare impacts of several climate scenarios demonstrate that a model which assumes irrigation is exogenous provides a biased estimate of the welfare effects of climate change. If dryland and irrigation are to be estimated separately in the Ricardian model, irrigation must be modeled endogenously. The results also indicate that African agriculture is sensitive to climate change. Many farmers in Africa will experience net revenue losses from warming. Irrigated farms, on the other hand, are more resilient to temperature change and, on the margin, are likely to realize slight gains in productivity. But any reduction in precipitation will be especially deleterious to dryland farmers, generally the poorest segment of the agriculture community. The results indicate that irrigation is an effective adaptation against loss of rainfall and higher temperatures provided there is sufficient water available. This will be an effective remedy in select regions of Africa with water. However, for many regions there is no available surface water, so that warming scenarios with reduced rainfall are particularly deleterious.

The environment and security literature has argued that freshwater scarcity often leads to inter-state conflict, and possibly acute violence. The contention, however, ignores the long history of hydro-political cooperation exemplified by hundreds of documented agreements. Building on a theory that considers the relationship between scarcity and hydro-political cooperation, this paper empirically investigates why treaties are negotiated for some rivers and between some riparians, and not others. The paper suggests that long-term water scarcity has a significant influence on levels of cooperation. Additional variables considered include trade, level of governance among the riparian states, and the geography of the river. Findings confirm that cooperation and scarcity embody a concave (inverted U curve) relationship. Governance has a positive impact on cooperation. In addition, riparians may either arrange the use of their scarce water resources via a treaty or trade (and indirectly exchange [virtual] water). Scarcity, governance, and trade were found to be most salient in explaining levels of cooperation while geography is significant in some of the estimates.

Measurement of the likely magnitude of the economic impact of climate change on African agriculture has been a challenge. Using data from a survey of more than 9,000 farmers across 11 African countries, a cross-sectional approach estimates how farm net revenues are affected by climate change compared with current mean temperature. Revenues fall with warming for dryland crops (temperature elasticity of -1.9) and livestock (-5.4), whereas revenues rise for irrigated crops (elasticity of 0.5), which are located in relatively cool parts of Africa and are buffered by irrigation from the effects of warming. At first, warming has little net aggregate effect as the gains for irrigated crops offset the losses for dryland crops and livestock. Warming, however, will likely reduce dryland farm income immediately. The final effects will also depend on changes in precipitation, because revenues from all farm types increase with precipitation. Because irrigated farms are less sensitive to climate, where water is available, irrigation is a practical adaptation to climate change in Africa.

The authors examine wage inequalities in Sri Lanka's formal sector using data from the Sri Lanka Integrated Survey 1999-2000. The study aims to: a) investigate whether the labor market is characterized by wage disparities among ethnic and gender groups; b) identify the determinants of wages and the factors that affect the wage differential; c) analyze the determinants of wages across the conditional wage distribution; and d) disaggregate the ethnic or gender wage disparities where observed into a component affected by the endowment of productive characteristics, as well as a component affected by the returns to those productive characteristics in the labor market. The authors find that ethnicity is not a significant determinant of wages. The result is robust to different specifications. In addition, ethnicity is not significant in any of the emotional quantiles estimated. However, there is gender disparity in wage rates in Sri Lanka. The magnitude of this disparity varies depending on the worker's ethnicity. This gender wage disparity varies by about 10 percent for Tamils and 48 percent among other ethnicities. In addition, the authors find that much of the gender disparity is not explained by productive characteristics, implying that discrimination against women may play a role. The quantile regression estimates indicate that the premium paid to male workers in the labor force is more pronounced in the upper conditional wage rate distribution.