Given current conditions, the damage would hit China between 2030 and 2050.

The report, based on an inventory of greenhouse gas emissions carried out between 1990 and 1994, was presented at the 10th annual UN climate change conference, meeting here December 6-17.

Some 5,000 scientists, environmental activists and government officials from nearly 190 countries attended. A focus this year is preparing to implement the 1997 Kyoto accord, the world's most ambitious and complex environmental treaty.

The accord legally commits 39 industrial nations and territories to trim their output of six greenhouse gases -- especially carbon dioxide -- by at least 5.2 percent by 2012, compared with 1990 levels.

Russia's ratification in November gave the protocol the final stamp of approval needed to go into force on February 16. China signed the accord and ratified it in 2002.

"Simulations indicate that the potential food production would decrease by ten percent due to climate change and extreme weather events during 2030-2050, under the present cropping system, (given) present crop varieties and present management levels," reads an executive summary of the China report.

"Climate warming would speed up plant growth and shorten the crop growing period," read the report, adding that there would be "an overall decreasing trend for wheat, rice and maize yield."

China's climate change trend corresponds "to the general trend of global climate change," the report said, noting that the 1990's "was one of the warmest decade in the last 100 years."

The warming was most noticeable across northern China, according to the report.

While the number of cold snaps is likely to decrease, heat waves "are likely to increase, and the drought and flooding are likely to be enhanced."

There has been "a continuous drought in the north China plain since the 1980s, while flooding disasters have happened frequently in southern China. This impact has been especially enhanced since the 1990s," the report read.

Since the 1950s the sea level has risen along China's coast, a trend that "has become significantly more obvious in the past few years."

The ocean is currently rising at a rate of 1.4 to 2.6 millimeters (0.05 to 0.1 inches) a year, and the current projections are for a rise of between 31 to 65 centimeters (12 to 25.5 inches) by 2100, aggravating coastal erosion and increasing the amount of ocean water entering river, thus degrading "the fresh water quality and adversely affect the fresh water supply along the river mouth," the report read.

In an interview Monday with AFP, the head of the Chinese delegation, Gao Feng, insisted that China has already done much to fight global warming.

China's pollution levels, however, remain high because of its reliance on coal as an energy source.

Future actions to decrease greenhouse gas emissions include increased energy efficiency and recycling. "We will try to use some cleaner energies like nuclear power," he said.

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