LONDON (Kyodo) Rising temperatures and extreme weather conditions brought on by climate change could reduce rice yields by as much as 40 percent by the end of the 21st century in much of central and southern Japan, according to research data released by the Intergovernmental Panel on Climate Change.
The official public launch of the full IPCC assessment — "Climate Change 2007: Impacts, Adaptation and Vulnerability" — identifies world regions most likely to be affected by climate change and highlights crops and agriculture under threat in Asia as a whole.
Evidence included in the report that was gathered by the International Rice Research Institute suggests that rice yields "decrease by 10 percent for every 1 degree increase in growing-season minimum temperature," leading to a decline in potentially good agricultural land.
Even the irrigated lowlands in many prefectures in central and southern Japan are thought likely to suffer from the projected doubling of atmospheric carbon dioxide and the resultant occurrence of "heat-induced floret sterility." Research into the climate-related biodiversity loss in Asia also revealed that besides changes in the flowering date of Japanese cherry trees, there has been a "decrease in alpine flora in Hokkaido and other high mountains and the expansion of the distribution of southern broad-leaved evergreen trees."
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