Crop selection : adapting to climage change in Africa

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.Crops&Crop Management Systems,Climate Change,Agriculture&Farming Systems,Renewable Energy,Global Environment Facility

A ricardian analysis of the impact of climate change on African cropland

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 areespecially 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.Climate Change,Environmental Economics&Policies,Global Environment Facility,Common Property Resource Development,Crops&Crop Management Systems

How will climate change shift agro-ecological zones and impact African agriculture ?

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.Climate Change,Common Property Resource Development,Forestry,Crops&Crop Management Systems,Global Environment Facility

Scarperation : an empirical inquiry into the role of scarcity in fostering cooperation between international river riparians

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.Water and Industry,Water Supply and Sanitation Governance and Institutions,Environmental Economics&Policies,Town Water Supply and Sanitation,Water Conservation

The impact of climate change on African agriculture : a ricardian approach

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.Environmental Economics&Policies,Climate Change,Common Property Resource Development,Rural Development Knowledge&Information Systems,Global Environment Facility

The Process and Performance of Decentralization of River Basin Resource Management: A Global Analysis

This paper focuses on empirically assessing determinants of river basin management decentralization, which is poorly understood while growing in popularity 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 water scarcity is found to be a stimulus to reform and financially endowed or developed basins do not outperform poor an underdeveloped basins; conditions improving decentralization performance include: existence of dispute resolution mechanisms; greater financial responsibility of users; and external government financial support of basin budget.Resource /Energy Economics and Policy,

The impact of water supply variability on treaty cooperation between international bilateral river basin riparian states

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 mainlyon 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.Water Supply and Sanitation Governance and Institutions,Water and Industry,Town Water Supply and Sanitation,Drought Management,Common Property Resource Development

Differential adaptation strategies by agro-ecological zones in African livestock management

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.Livestock&Animal Husbandry,Wildlife Resources,Peri-Urban Communities,Rural Urban Linkages,Dairies&Dairying

Long-term adaptation : selecting farm types across agro-ecological zones in Africa

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.Crops&Crop Management Systems,Climate Change,Agriculture&Farming Systems,Livestock&Animal Husbandry,Rural Development Knowledge&Information Systems

Differential adaptation strategies to climate change in African cropland by agro-ecological zones

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.Crops&Crop Management Systems,Climate Change,Food&Beverage Industry,Renewable Energy,Rural Poverty Reduction