Climate change is becoming an existential threat with warming in excess of 2°C within the next three decades and 4°C to 6°C within the next several decades. Warming of such magnitudes will expose as many as 75% of the world’s population to deadly heat stress in addition to disrupting the climate and weather worldwide.
Rising temperatures because of increased emissions of long-lived greenhouse gases (LLGHGs) have had and will continue to have significant negative impacts on crop yields. However, other climate changes caused by short-lived climate pollutants (SLCPs) are also significant for agricultural productivity. The SLCPs black carbon and ozone impact temperature, precipitation, radiation, and—in the case of ozone—are directly toxic to plants.
At last, all the major emitters of greenhouse gases (GHGs) have agreed under the Copenhagen Accord that global average temperature increase should be kept below 2
Over a four-day period in December 1952, a thick still fog settled on London. By the time it dissipated, an estimated 5,000 people had been killed. The culprit was the smoke and sulphur particles belching forth from thousands of chimneys throughout the city. Soot or black carbon is a major component of smoke.
Most initiatives to slow global warming involve reducing carbon dioxide emissions. Little attention has been given to reducing emissions of the light-absorbing particles known as "black carbon" or the gases that form ozone--even though doing so would be easier and cheaper and have a more immediate effect.
Greenhouse gases (GHGs) warm the surface and the atmosphere with significant implications for rainfall, retreat of glaciers and sea ice, sea level, among other factors. About 30 years ago, it was recognized that the increase in tropospheric ozone from air pollution (NOx, CO and others) is an important greenhouse forcing term.
Increasing amount of soot, sulphates and other aerosol components in atmospheric brown clouds (ABCs) are causing major threats to the water and food security of Asia and have resulted in surface dimming, atmospheric solar heating and soot deposition in the Hindu Kush-Himalayan-Tibetan (HKHT) glaciers and snow packs.
