For more than half of humanity, rice is life. It is the grain that has shaped the cultures, diets, and economies of billions of people in Asia. For them, life without rice is simply unthinkable.
Rice reality : Between now and 2020, 1.2 billion new rice consumers will be added in Asia. Feeding these people will require the greatest effort in the history of agriculture: rice production must be increased by one third from today’s 320 million tons to 420 million tons. Farmers will have to grow an extra 3.7 million tons every year—at the very time that rice land is decreasing and the remaining fields seem to be wearing out. Today, there is barely enough rice for everyone. And in some places, because of political and economic turmoil, there is not enough—and people are going hungry.
What about tomorrow? If we do not begin to respond to today’s cries for help, Asia’s future will be bleak.
Environmental woes : Growing more and more rice from less and less land, however, may simply not be sustainable. Chemical pesticides are already polluting the lakes, rivers, and groundwater. Genetic biodiversity is eroding, salinity is encroaching farther inland, and there is less water for irrigation. Air and water pollution are already problems in many places.
What kind of environment will our children inherit?
Rhythm of life : Grown in Asia for at least 10,000 years, rice has richly influenced the cultures and lives of billions of people. In the old societies of Asia, rice dictates the rhythm of life. It is the grain that links Heaven and Earth, gods and mortals. Throughout the region, rice dominates customs, beliefs, rituals, and celebrations.
But as societies become affluent, they are slowly becoming less attached to rice. And the death of an elder often means the loss of age-old traditions and legends. Who will preserve the priceless rice heritage?
Teetering on the edge : In much of Asia, where rice is the essence of survival, poor people in both cities and rural areas spend half to three fourths of their incomes on rice—and only rice. Keeping rice prices within their means is an absolute must for social, economic, and political stability—and for promoting development and reducing poverty. The current Asian economic crisis is a sobering reminder that rice cannot be taken for granted. For Asia, rice sufficiency is the foundation of a healthy and vibrant society. Asia will be prosperous only if it can feed itself.
Before time runs out : In recent years, traditional western funding sources for global rice research have been drying up, and the budgets of national rice programs in Asia are inadequate to support long-term research programs. But much remains to be done. Rice research must continue to provide better ways of coaxing more rice from less land while preserving the fragile environment.
Rice farming, if it is to be attractive to future generations, must be transformed into a respected and economically profitable profession. Asians must become more conscious of the importance of rice in their lives. And the priceless rice cultural heritage must also be preserved for the education and enjoyment of posterity. Because of the magnitude of these endeavors, no one organization can do it all. Collaboration among diverse partners is the key.
To succeed, this massive effort must be well coordinated, timely—and well funded. Because more than 90 percent of the world’s rice is grown and consumed in Asia, Asians must become responsible for financing rice research and development. A new regional initiative is needed to help keep Asia’s rice bowls full.
Human activities are releasing greenhouse gases into the atmosphere.
Carbon dioxide is produced when fossil fuels are used to generate energy and when forests are cut down and burned. Methane and nitrous oxide are emitted from agricultural activities, changes in land use, and other sources. Artificial chemicals called halocarbons (CFCs, HFCs, PFCs) and other long-lived gases such as sulphur hexafluoride (SF6) are released by industrial processes. Ozone in the lower atmosphere is generated indirectly by ,amongst other things, automobile exhaust fumes and other sources.
Rising levels of greenhouse gases are already changing the climate.
By absorbing infrared radiation, these gases control the way natural energy flows through the climate system. In response to humanity's emissions, the climate has started to adjust to a "thicker blanket" of greenhouse gases in order to maintain the balance between energy arriving from the sun and energy escaping back into space. Observations show that global temperatures have risen by about 0.6 ˚C over the 20 th century. There is new and stronger evidence that most of the observed warming over the last 50 years is attributable to human activities.
Climate models predict that the global temperature will rise by about 1.4 – 5.8°C by the year 2100.
This change would be much larger than any climate change experienced over at least the last 10,000 years. The projection is based on a wide range of assumptions about the main forces driving future emissions (such as population growth and technological change) but does not reflect any efforts to control emissions due to concerns about climate change. It is based on current emissions trends and assumes that no efforts are made to limit greenhouse gas emissions. There are many uncertainties about the scale and impacts of climate change, particularly at the regional level. Because of the delaying effect of the oceans, surface temperatures do not respond immediately to greenhouse gas emissions, so climate change will continue for hundreds of years many decades after atmospheric concentrations have stabilized. Meanwhile, there is new and stronger evidence that most of the warming observed over the last 50 years can be attributed to human activities.
Human society will face new risks and pressures.
Food security is unlikely to be threatened at the global level, but some regions are likely to experience food shortages and hunger. Water resources will be affected as precipitation and evaporation patterns change around the world. Physical infrastructure will be damaged, particularly by sea-level rise and by extreme weather events. Economic activities, human settlements, and human health will experience many direct and indirect effects. The poor and disadvantaged are the most vulnerable to the negative consequences of climate change.
In this summary we look first at the possible biophysical responses of agro ecosystems to the specific environmental changes that are anticipated as a result of the buildup of global greenhouse gases, and then at the range of adaptive actions that might be taken to ameliorate their effects. It’s including discussions of regional and global assessments, the effects of uncertainty, thresholds, and surprises, and the possible consequences of global warming on agricultural sustainability and food security.