"If it's sunny on August 25, 2003, sprinkle water at the gates of your homes and offices at noon." Japan's Ministry of Land Infrastructure and Transport supported this refreshing attempt to combat the heat-island effect in Tokyo. The heat island effect is abnormal warming of the atmosphere due to a high concentration of heat-absorbing buildings and roads in cities.

The custom of sprinkling water on gardens and streets to lay the dust and for cooling - called uchimizu in Japanese - used to be seen everywhere in Japan. The wisdom of uchimizu, which was particularly common in the Edo Period (1603-1867), may again become an effective measure to mitigate the heat-island effect. During this period, Tokyo was called Edo.

Some researchers estimate that sprinkling one liter of water per square meter can reduce the ground temperature by more than two degrees Celsius. Moreover, this two-degree decrease can lead to a reduction of up to four percent in maximum power generation demand per hour. The Ministry of Land, Infrastructure and Transport of Japan, which supports this campaign, will help evaluate the effectiveness of this activity.

This campaign also aims at promoting secondary use of rainwater and used bathwater.





Posted: 2003/09/27 11:51:50 AM
Japanese version

TAG Food/Water , Global warming , NGO/Citizen