Climate Change, Agriculture, and Food Security in Tanzania

The consequences of climate change for agriculture and food security in developing countries are of serious concern. Due to their reliance on rain-fed agriculture both as a source of income and consumption, many low-income countries are generally considered to be most vulnerable to climate change. Here, we estimate the impact of climate change on food security in Tanzania. Representative climate projections are used in calibrated crop models to predict crop yield changes for 110 districts in Tanzania. These results are in turn imposed on a highly-disaggregated, dynamic economy-wide model of Tanzania. We find that, relative to a no climate change baseline and considering domestic agricultural production as the principal channel of impact, food security in Tanzania appears likely to deteriorate as a consequence of climate change. The analysis points to a high degree of diversity of outcomes (including some favourable outcomes) across climate scenarios, sectors, and regions. The economic modelling indicates that markets have the potential to smooth outcomes on households across regions and income groups, though noteworthy differences in impacts across households persist both by region and by income category.climate change; agriculture; food security; crop model; CGE model; Tanzania

A Systems Approach to Design of Agricultural Drainage Systems in Egypt

Agricultural drainage systems provide the principal means of coping with waterlogging and salinization of soils, two of the major environmental problems of agriculture. To illustrate the enormity of the problems caused by salinization, one need only note that the total soil loss in the world due to secondary salinization is larger than the amount of soil presently irrigated worldwide. Dr. Strzepek's paper is written from a perspective unusual at IIASA. Generally, the type of decision which concerns IIASA scientists is one of feasibility -- whether a specific project should be developed and what the principle features of such a project would be. In contrast, Dr. Strzepek's approach is to discuss the ways in which the techniques of systems analysis can be used to solve universal problems of engineering design. This methodological point of view is thus of interest not only to the task "Environmental Problems of Agriculture, "but also to the entire institute and decisionmakers in general. The background work for this paper was initiated at the Massachusetts Institute of Technology, but the paper was written at IIASA

Adaptation Advantage to Climate Change Impacts on Road Infrastructure in Africa through 2100

The African continent is facing the potential of a US$183.6 billion liability to repair and maintain roads damaged from temperature and precipitation changes related to climate change through 2100. As detailed, the central part of the continent faces the greatest impact from climate change with countries facing an average cost of US$22 million annually, if they adopt a proactive adaptation policy and a US$54 million annual average, if a reactive approach is adopted. Additionally, countries face an average loss of opportunity to expand road networks from a low of 22 per cent to a high of 235 per cent in the central region.infrastructure, climate change, roads, cost estimates

Adaptation advantage to climate change impacts on road infrastructure in Africa through 2100

The African continent is facing the potential of a US$183.6 billion liability to repair and maintain roads damaged from temperature and precipitation changes related to climate change through 2100. As detailed, the central part of the continent faces the greatest impact from climate change with countries facing an average cost of US$22 million annually, if they adopt a proactive adaptation policy and a US$54 million annual average, if a reactive approach is adopted. Additionally, countries face an average loss of opportunity to expand road networks from a low of 22 per cent to a high of 235 per cent in the central region

Inter-sectoral Water Use in South Africa: Efficiency Versus Equity

While water supply sources are dwindling in South Africa, the demand for the scarce water resource is increasing. This situation requires a switch from supply to demand management of water in the country. The study updates the 1999 social accounting matrix for South Africa, using the Trade and Industrial Policy Strategies (TIPS) time series data, STATSA's 2001 census report and 2000 water accounts, the 2002 national income accounts, published by the South African Reserve Bank (SARB) and the Water Resource Management Strategy (WRMS) registration data. Using the updated SAM, the contribution of water to economic development in South Africa is estimated through the traditional SAM multiplier analysis. The paper then investigates the impact of reallocating water among the production sectors, on the basis of economic efficiency, on output growth, factor remuneration and households' income generation. The computational and simulation results show that, though agriculture is among the sectors that have the least marginal value of water, water reallocation based on marginal values will reduce the incomes of the poorest households, and put at stake the livelihoods of the most vulnerable population. Scenario analyses suggest that this effect will be minimal if marginal productivity consideration for inter-sectoral water reallocation is reduced to 30%, while intra-sectoral water reallocation on the basis of efficiency is currently viewed as the most viable option.SAM multipliers, output growth, factor remuneration, income generation, efficiency, equity, R20, Resource /Energy Economics and Policy, C67, D57, L60, Q25,

Infrastructure and climate change: a study of impacts and adaptations in Malawi, Mozambique, and Zambia

The African Development Bank has called for $40 Billion USD per year over the coming decades to be provided to African countries to address development issues directly related to climate change. The current study addresses a key component of these issues, the effect of climate change on the road infrastructure of Malawi, Mozambique, and Zambia. The study incorporates a stressor-response approach to estimate the effects of projected precipitation, temperature, and flooding changes on the paved and unpaved road infrastructure of these countries. The paper highlights the result of running 425 climate scenarios for each road type and policy option from 2010 to 2050. Based on this broad analysis, it is estimated that the three southern African countries are facing a potential$596 million price tag based on median climate scenarios to maintain and repair roads as a result of damages directly related to temperature and precipitation changes from potential climate change through 2050. The challenge for policy makers is to determine the potential risk that a country is facing based on the uncertainties associated with the multiple aspects of climate change modeling. This article is part of a Special Issue on “Climate Change and the Zambezi River Valley” edited by Finn Tarp, James Juana, and Philip Ward

Examining the Impacts of Land-Use Change on Hydrologic Resources

The research community over the past several years has put a great effort into studying the potential impacts of a changing climate. But the issues that face the world today encompass greater change than just that of climate. For instance, there are changes due to population dynamics (such as migration), economics, and the way that land is used. Water resources are affected specifically by changes in climate and land use. A water balance developed for the purpose of examining climate change was extended to allow analysis of impacts from land-use change. In addition, it was modified so that a watershed could be modeled by multiple smaller units within the basin. Two methodologies were applied to break the basin into smaller parts: first, hydrologic boundaries of major tributaries were used, and second, a delineation based on five classes of land-use type, which included tundra, forest, rangeland, agriculture, and urban land, was created. The model originally had three parameters which were calibrated statistically. A goal of this project was to take a step towards making these parameters physically-based in the watershed, thereby avoiding the need for statistical calibration which might allow parameters to mask interconnections in the hydrologic process. The parameter which represents maximum soil moisture capacity was therefore set based on land-use type. The South Platte Basin upstream of the town of Masters, Colorado was chosen as a case study basin. The study included eight sub-basins delineated by hydrologic boundaries and the five land classes mentioned previously. A climate change sensitivity analysis was performed and a hypothetical land-use scenario was analyzed. This hypothetical scenario increased the percentage of urban land and removed all agriculture. In addition, some rangeland was converted to forested land. These tests were examined individually and in a combined scenario. Results found that the land-use scenario estimated greater runoff and acted to mitigate negative effects and enhance positive impacts of climate change. The magnitude of the impact of land-use change was found to be of the same order as that of climate change, and it therefore further warrants further research into possible effects of such changes. The study clearly demonstrated the sensitivity of model results to inclusion of land-use change, and the need for further development of the hydrological model for the Yellow River basin in North China, a water-critical region of the LUC project study area

Analysis of Tile Drainage Design Policies in Egypt

Recent field studies have shown that in some cases tile drains have been ineffective in increasing crop production. This paper examines the effect that the policies of 40 meter minimum spacing and aggregating large areas under a single drain design may have upon the effectiveness of tile drains. An approach that synthesizes crop yield response, the physics of drainage and economics is used to determine the possible cost of these two policies. A case study from the Nile Delta is examined. The paper shows that these policies can have a great effect upon the efficiency of tile drain performance under certain conditions

MITSIM-2: A Simulation Model for Planning and Operational Analysis of River Basin Systems

Mathematical simulation models have become a common tool for the analysis of water resources problems . The models fall in two categories, those for studying long range planning of water resources development and those for the analysis of detailed operation of water resource systems. The planning models tend to be of a longer time step usually on the order of one month, while the operational models may need a time steps of days and in some cases hours. This paper presents a model that incorporates features of both planning models and operational models. MITSIM-1, a river basin simulation model for long range planning was modified to account for daily operational rules and complex institutional constraints within a basin. A new model ,MITSIM-2 , was developed that provides quasi-daily operational rules for reservoirs and irrigation requirements, while retaining the features necessary for efficient long range planning of basin development . MITSIM-2 is applied to the regional water supply system of South Western Skane to demonstrated its applicability to incorporate planning and operational analysis successfully in one model