Global warming could imperil future rice crops: researchers

TSUKUBA, Ibaraki Pref. (Kyodo) Global warming poses a threat to Japan's future rice crops and thus its food security, a Japanese agricultural research group warned Wednesday.

If farming methods are left unaltered, Japan's rice harvest will fall by 10 percent by 2090 as a result of global warming, according to the group.

Researchers at the National Institute for Agro-Environmental Sciences in Tsukuba, Ibaraki Prefecture, project that while harvests will increase in colder regions such as Hokkaido, the national average will fall by 10 percent.

If cultivation methods remain unchanged, the warmer regions of Chugoku and Shikoku in western Japan and Kyushu in the southwest will see a rice crop decrease of 15 percent to 18 percent, the group forecasts.

The quality of rice may also decline as warmer temperatures shorten the time for rice to ripen.

Japan produces about 10 million tons of rice a year, according to data provided by the Agriculture, Forestry and Fisheries Ministry.

"It might be difficult for Japan to secure its food supply in the future," said Isamu Noguchi, head of the institute's meteorological research group.

In order to sustain cultivation of Japonica short-grained rice, the staple food in Japan, either a new variety that is resistant to high temperatures will have to be developed or farmers will have to adjust the rice planting season, according to Noguchi.

The predictions are based on forecasts that temperatures in Japan will rise by 3.3 to 3.8 in 100 years from the average for 1990.