In Malaysia, at least 12 people have died and 8,000 were forced to flee their homes as flood waters rose in the north of the country. In Australia, the worst floods in 50 years have put a third of New South Wales and part of Queensland under water. The latest weather woes follow hard on the heels of flooding this year in Vietnam, Cambodia, Bangladesh and eastern India that has killed hundreds of people and left millions homeless. At the same time, severe drought has wrought havoc in Iran, Afghanistan and the former Soviet Central Asian republics. United Nations weather experts say rainfall and drought in Asia this year have been in the extremes of what has been recorded over the last 100 years, and this suggests a profound shift in the world climate.
Some greenhouse gases occur naturally in the atmosphere, while others result from human activities.
Naturally occuring greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Certain human activities, however, add to the levels of most of these naturally occurring gases. Methane is emitted during the production and transport of coal, natural gas, and oil. Methane emissions also result from the decomposition of organic wastes in municipal solid waste landfills, and the raising of livestock. Nitrous oxide is emitted during agricultural and industrial activities, as well as during combustion of solid waste and fossil fuels.