The World Meteorological Organization (WMO) has activated its Environmental Emergency Response mechanism to monitor the meteorological conditions in and around the quake-hit areas of Japan, the WMO announced on Tuesday.

The mechanism, according to the UN meteorological body, was activated at an early request by the International Atomic Energy Agency (IAEA), to assistant its effort to contain the nuclear disaster, following the devastating earthquake and tsunami in Japan.

Three WMO's regional specialized meteorological centers in Beijing, Tokyo and Obninsk (Russian) were tasked to monitor the radio-active particles leaked from the damaged Japanese nuclear reactors and providing round the clock information to the IAEA and weather and hydrological services in the region.

Atmospheric trajectories and dispersions charts corresponded to the times of the two explosions at the Fukushima nuclear power plant provided to the IAEA showed winds were blowing to the northeast and east, towards the open ocean.

In a video message delivered Tuesday, WMO Secretary-General Michel Jarraud said, contrary to the Tchernobyl nuclear disaster, which sent the radioactive particles high into atmosphere to remain for a long time and covering a vast zone, available information from Japan indicated that for the time being the particles were confined to the lower atmosphere.

However, considering the constantly changing weather patterns, he said 24-hour operational link between the monitoring centers and decision-makers was crucial.