North Korea says the incident of yellow dust storms has grown dramatically since 2000, damaging the nation's public health, agriculture and economy.

An almanac published by the North's official Korean Central News Agency said Monday that the higher frequency of the yellow dust phenomenon decreased sunlight exposure ten percent and dropped the average daytime temperature two or three degrees.

Massive amounts of yellow dust float eastward every year from the Gobi Desert, northwestern China and the Yellow River region.

The almanac said yellow dust was particularly bad in 2002 at ten tons per square kilometer of dust, adding "it rained mud" in February and March 2004.

Harmful substances such as silicides and viruses in yellow dust can cause disease in humans.

The North said it has formed a team of weather, environmental and geographical experts to closely monitor yellow dust and issue warnings.