LA PAZ, Dec. 21 (Xinhua) -- The surface of the glaciers at the Real Mountain Range in the Andes has been reduced by 24 percent, about 84 square km, from 1987 to 2004 due to climate change, the United Nations Population Fund (UNFPA) reported Monday.

    According to the UNFPA representative in Bolivia, Jaime Nadal, the disintegration process will continue affecting mainly the snowy mountains of Bolivia and Peru, leading to a critical situation due to thawing glaciers.

    Nadal said that in Bolivia, the loss of the glaciers in Huayna Potosi and Chacaltaya has caused a problem for the water supply in the cities of La Paz and El Alto.

    "The glaciers that used to supply large amounts of clean as well as crystal-clear water to those communities have been sharply reduced in the last 15 to 20 years," the UNFPA said.

    The UNFPA added that demographic control is very important to avoid tragic results of the climate change.

    Almost all of the tropical glaciers of the hemisphere are located in the Andes, while 20 percent of them are in Bolivia.