Global warming may cause climate extremes, such as floods, droughts and heatwaves, to become more frequent in the future. A new study of 16 developing countries has assessed the impact of these extremes on poverty and found that the urban poor may be particularly vulnerable, with poor grain harvests increasing the price of food.
For poor people in developing countries, staple grains, such as rice and maize, make up a significant part of daily diet; the prices of which are important determinants of their cost-of-living. For farmers, grains are also an important source of earnings. Climate change may detrimentally affect crop yields which in turn will have an impact on the price of food and make more people vulnerable to poverty.
The researchers analysed the wettest, hottest and driest climate events across the globe for two 30-year time periods: 1971-2000 and 2071-2100. The most extreme wet events of the late 20th century to occur in a thirty year period will occur more often and with greater intensity in the future.
The results suggest that all countries will also experience hotter and more frequent heat extremes. For instance, parts of the northern Mediterranean will experience more than a 2700 per cent increase in extreme hot episodes. In addition, most countries will have more severe and frequent droughts. The occurrence of these events over Mediterranean Europe, for example, will increase by more than 800 per cent and the duration of the drought will increase by 60 per cent.
However, some countries, including Colombia and Uganda, will experience less intense and less frequent droughts. Tanzania, Indonesia and the Philippines will also be faced with more frequent droughts, but which are less intense.
For the current climate, the researchers statistically estimated the distribution of changes in grain productivity in 16 developing countries in Africa, Asia and Latin America in the late 20th Century, from which they then determined the impact of a one-in-thirty climate extreme on grains production.
The study found that all people in developing countries would be more vulnerable to extreme climate events. The urban poor, dependent on a wage for labour, are a particularly vulnerable group. Extreme climate events would increase food prices for these populations, and may result in populations dropping below the poverty level.
Although agricultural households are also affected by these extreme climate events, through lower grain harvests, they would benefit from higher food prices and are generally less vulnerable to falling into poverty. However, this depends on local conditions.
Policy makers responsible for international development can tailor adaptation strategies in developing countries to lessen the adverse impacts of climate change. This includes investing in infrastructure, such as sustainable irrigation systems in Tanzania, and ensuring farmers have access to credit and information to help them mitigate the effects of climate change.
Source: Ahmed, S.A., Diffenbaugh, N.S. and Hertel, T.W. (2009). Climate volatility deepens poverty vulnerability in developing countries. Environmental Research Letters. 4: 034004 (8pp) doi:10.1088/1748-9326/4/3/034004.
Contact: sahmed20@worldbank.org [1]