IMPACT OF GLOBAL WARMING AND CLIMATE CHANGE ON AGRICULTURE
Global warming in short-term is likely to favour agricultural production in temperate regions (largely northern Europe, North America) and negatively impact tropical crop production (South Asia, Africa). This is likely to have consequences on international food prices and trade and hence our food security. Small changes in temperature and rainfall could have significant effect on quality of cereals, fruits, aromatic, and medicinal plants with resultant implications on their prices and trade. Pathogens and insect populations are strongly dependent upon temperature and humidity. Increases in these parameters will change their population dynamics resulting in yield loss. Increasing sea and river water temperature is likely to affect fish breeding, migration, and harvests.
Although increase in carbon dioxide is likely to be beneficial to several crops, associated increase in temperatures, and increased variability of rainfall would considerably impact food production. Recent IPCC report and a few other global studies indicate a probability of 10 – 40% loss in crop production in India with increases in temperature by 2080 – 2100.
There are a few Indian studies based on theme and they generally confirm similar trend of agricultural decline with climate change.
It is, however, possible for farmers and other stakeholders to adapt to a limited extent and reduce the losses. Simple adaptations such as change in planting dates and crop varieties could help in reducing impacts of climate change to some extent. For example, the Indian Agricultural Research Institute study quoted above indicates that losses in wheat production in future can be reduced from 4 – 5 million tons to 1 – 2 million tons if a large percentage of farmers could change to timely planting and changed to better adapted varieties. This change of planting would, however, need to be examined from a cropping systems perspective.