中国气候变化信息网 China Climate Change Info-Net

The UN Intergovernmental Panel on Climate Change (IPCC), the top world authority on global warming, issued a report on Friday based on the findings of 2,500 scientists.

More than 100 countries agreed on the following:

PROBLEMS SO FAR

-- Since the mid-20th century, rising temperatures are changing the face of the globe, mostly due to human production of greenhouse gases.

-- Researchers examined areas such as when trees sprout, compiled 29,000 sets of data and found that 90 percent of them pointed to global warming.

-- They say, with "medium confidence", that there have been more heat-related deaths in Europe, more infectious diseases and more pollen allergies because of global warming.

FUTURE FLOODS, DROUGHTS

-- Dry areas will get drier. In some countries, crop yields could drop by 50 percent by 2020.

-- The effect on agriculture will be uneven, with production increasing modestly in some places as it falls in others. As temperatures rise, the effects will change.

-- At first, commercial timber production will increase modestly, but the effects will vary around the globe.

-- More than one billion people may face shortages of fresh water by 2050, especially as demand rises with living standards in Central, South, East and Southeast Asia.

-- By the 2080s, millions of people will be threatened by floods because of rising sea levels, especially in the mega-deltas of Asia and Africa and on small islands.

-- Mountains will have fewer glaciers, less snow, less winter tourism and as much as 60 percent species loss by 2080 if high emissions of greenhouse gases continue. Winter flooding will increase and less water will be available for energy, agriculture and human consumption.

OCEANS AND SPECIES

-- Coral bleaching will cause widespread mortality unless the coral can adapt. The Great Barrier Reef could lose "significant" biodiversity by 2020.

-- Between 20 to 30 percent of plant and animal species examined to date face an increased risk of extinction if the average global temperature rise exceeds 1.5-2.5 degrees Celsius.

-- Health will suffer from increases in malnutrition and heat waves, floods, storms and droughts.