The earth’s climate is dynamic, promoting the evolution of various living forms and changing the structure and chemical composition of the atmosphere. Over the past few decades, acceleration in the human-induced changes in the earth’s climate has become the focus of scientific and social scrutiny. The gaseous composition of the atmosphere has undergone a significant change mainly through increased industrial emissions, fossil fuel combustion, widespread deforestation and burning of biomass, and changes in land use and land management practices.
According to scientists of the Indian Agriculture Research Institute (IARI), these anthropogenic activities have resulted in an increased emission of radiatively active gases, e.g., carbon dioxide, methane, and nitrous oxide, popularly known as the ‘greenhouse gases’. These greenhouse gases trap the outgoing infrared radiation from the earth’s surface.
Global warming, in turn, leads to regional changes in climate-related parameters such as rainfall, soil moisture, and sea level. The extensive and frequent occurrence of climatic extremes such as droughts, heat, and floods in the last decade in many parts of the world may be the fallout. The sea level has risen by 10-20 cm with regional variations. Similarly, snow cover is also believed to be gradually decreasing.
More floods, frequent droughts and forest fires, decrease in agricultural and aqua-cultural productivity, displacement of coastal dwellers by sea-level rise and intense tropical cyclones, and the degradation of mangroves may be some of the likely consequences of climate change in Asia.
Such consequences could considerably affect the food supply and access through direct and indirect effects on crops, soils, livestock, fisheries, and pests. On the other hand, the increasing temperature can reduce crop duration, increase crop respiration rates, affect the equilibrium between crops and pests, hasten nutrient mineralisation in soils, decrease fertiliser use efficiencies, and increase evapotranspiration among others.
Uncertainty in precipitation causing droughts and floods has been responsible for many famines, rural poverty, and migration despite the development of impressive irrigation potentials. These environmental changes, particularly temperature increase and sea-level rise, could also affect fisheries directly and indirectly through changes in feed availability. Similarly, with increased temperatures, the changes in fodder and water availability may affect meat and milk production.
All these changes would have a tremendous impact on agricultural production and, hence, on the food security of any region. Several critical socioeconomic determinants of food supply, such as Government policies, capital availability, prices, and returns, infrastructure, land reforms, and inter-and intra-national trade, are also expected to be altered by environmental changes.
Alarmed by the possible impact of global climatic change on the quality of life of human beings, there has been a serious concern all over the world in understanding the processes and developing strategies to mitigate the negative effects. It has been realised by all that a change in environmental quality affects all aspects of life. Efforts are, therefore, needed to reduce the emission of greenhouse gases, which are mainly responsible for atmospheric warming.
The solution to such environmental issues is closely linked with the problems of socioeconomic problems. Each country or region addresses the problem with its individualistic perception of what is best suited for its economic development and not necessarily what is best for the world’s health. Therefore, such environmental problems generally involve conflicts between the interests of those who benefit greatly and those who benefit less or none at all.