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Most scientists now agree that global warming is inevitable, and that it will have major impacts on climates worldwide. It will take a long time to reverse this trend, and in the meantime adverse impacts on the poor in developing countries will be especially harsh. We must help them.

The poor can also help us, because they have been there before. Dryland inhabitants have always been adjusting to large variations in climate, both short and long-term. By looking back, we will find clues to our future.

We also view current climatic variability as a learning opportunity — in a sense, as a dress rehearsal for future climate change. By helping the dryland poor to cope better with current climate variability, we help them better prepare for the future.

Squall lines that bring unpredictable deluges to the West African drylands are the embryos of the Atlantic hurricanes that later hit the Caribbean and North America

At ICRISAT we are learning from poor land-users through village-level socio-economic studies, land-use surveys, and ‘farmer field schools.’ We also involve farmers in our plant breeding research to learn about the plant traits that they value most.

Villagers in India and in Southern/Eastern Africa, for example tell us they have noticed changes in the amount and irregular timing of rainfall in the past 30 years; whereas rainfall has been slowly increasing in Africa’s Sahel region over the past two decades (interspersed by punishing droughts). In all three regions farmers have adjusted cropping practices and the varieties of crops that they grow. We should work with them to build on their solutions.

More from more

Satellite data illustrate changing vegetation trends across Africa, especially the re-greening of the Sahel since the mid-1980s. Green: increasing vegetation; red: decreasing vegetation*

We must help farmers prepare not only for risks, but also for opportunities. Climate prediction models do not yet tell us with great certainty whether rainfall will increase or decrease in many dryland areas, or between seasons. Higher rainfall and in some areas warmer temperatures could even enable increases in agricultural productivity, but may also bring diseases, pests and invasive species.

To help farmers get a better handle on these uncertainties, we’ve partnered with meteorological services and leading climate modeling researchers worldwide. We blend their knowledge with our expertise on tropical dryland farming systems using climate-driven risk analysis. This involves the use of leading-edge tools such as weather-driven crop simulation models, spatial weather data generators, and seasonal climate forecasting models.

Nitrogen fertilizer is essential to boost yields, but can be risky in unpredictable climates because it stimulates plants to use more water. Computerized crop growth models combined with weather data allow scientists to quantify this risk vs. reward.**

We should also seek opportunities to make better use of natural resource assets, pools and flows. Take water, for example. Much of the rain that falls on the drylands, paradoxically, is ‘wasted’ from a farming point of view—water that is never picked up by plants because it comes in flood surges, or because soils are surface-sealed and unable to absorb it, or because crop roots are underdeveloped due to malnutrition and thus unable to take up the water efficiently from the soil. We are helping farmers devise ways to manage landscapes, soils and crops so that more of the water and nutrient resources are stored and used more efficiently and over a longer time period. This will prepare farm families to better endure the greater variability of rainfall that many expect in the future.

Likewise, we can get more from more by improving economic and social resource assets, pools and flows. Co-learning with farmers and research on how they innovate helps build social and knowledge capital, and extends their benefits more widely. These studies help us improve institutions and cooperation mechanisms such as community self-help and joint credit associations, micro-credit from socially-conscious lenders, market opportunities that diversify risk, and affordable insurance against severe drought. These increase farmers’ resilience in the face of both current climate variability and future climate change.

Breeders identify hardy millet varieties that can resist extreme stress conditions.

Learning from genes

Farmers have also been astute in their development and use of special breeds of livestock, crops and trees that are genetically engraved with astonishing adaptive traits, many of which we are yet to decipher.

They know that different plants vary for soil fertility requirements and tolerance to flooding, heat, insects and diseases, pressures that are all likely to be affected by climate change. Natural and farmer-aided selection have favored the evolution of remarkable traits such as ‘photoperiod sensitivity’, which ensures that the plants mature around the same calendar date each year regardless of planting date. This trait is valuable because farmers can only plant after the rains begin in earnest — a date that is unpredictable and varies widely from year to year.

Farmers insist on planting mixtures of genetically-different plants and varieties because they know that if a stress knocks out one genetic type, another is likely to survive it. They take this even further: they not only diversify varieties within crops, but they also grow a range of different crops, including trees that disrupt winds and moderate the baking heat and pounding storms that will increasingly punish crops as climate change kicks in.

ICRISAT helped farmers in the poor village of Powerguda become the first in India to sell carbon credits (147 tons of carbon worth US$645). The credits, bought by the World Bank, were earned by growing Pongamia trees that store extra carbon while yielding bio-diesel, yet another additional income source.

There is a lesson here for our mono-cultured world. We have been narrowing genetic diversity to fit our industrial agriculture over the last hundred years. We need to do a better job of protecting and utilizing our dwindling biodiversity assets, because with climate change on the way we will need them more than ever.

We are carrying this lesson forward to help farmers expand their agro-biodiversity and marketing options. By increasing the number of high-value crops, trees, shrubs, and herbs available for cultivation, and by growing them together in more diverse farming systems, farmers will be less vulnerable to climatic and economic shocks.

Together we can

To magnify our capacities and increase momentum on the crucial topic of climate variability, we are building a coalition with the Soil-Water Management Network of the Association for Strengthening Agricultural Research in East and Central Africa (ASARECA) and 15 national, regional and international organizations. This consortium is endorsed by the New Partnership for Africa’s Development (NEPAD) and its Comprehensive African Agricultural Development Plan (CAADP).

Farmers in the Sahel protect trees such as Faidherbia albida that tap deep water tables to provide shade and dry-season fodder for livestock, which in turn produce manure that improves crop production. Trees also moderate the land surface micro-climate and reduce wind erosion.

Investors have a key role to play too, because they make our work possible. Some say we owe it to the poor—after all, they are not the ones causing climate change. But they are helping us find solutions. Through increased investment and the use of modern scientific tools we can accelerate the pace and scope of research —helping the poor not only to survive, but to thrive.

by William D. Dar
Director General, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)

*Vegetation changes may reflect human activities as well as climatic variations. Data are differences between the periods 1985-1992 and 1996-2003 for averaged normalized difference vegetation indices (NDVI). Source: data processed by ICRISAT from the Global Inventory Modeling and Mapping Studies (GIMMS), University of Maryland.
** A simulation model (APSIM) was used to predict how maize would respond to fertilizer in a drought-prone, variable-rainfall area of Zimbabwe (Masvingo), using rainfall data from a 46-year period (1952-98). The model found that farmers were highly likely to enjoy a positive return on investment in nearly all years, gaining a 10-fold return in about half of the years when using micro-doses of just 17kg N/ha, exceeding the financial returns obtained from the conventionally recommended rate of 52kg/ha. These results have given confidence to researchers, extensionists and fertilizer enterprises to test micro-dosing with 200,000 dryland farmers in recent years.