Asian Pollution Fuelling North American Storms Satellite images
show that the north Pacific Ocean has recently become much
cloudier, particularly during winter. Over a large portion of
the ocean, between latitudes 30 north and 50 north, the area
covered by deep convective clouds increased by 20 to 50% in a
decade. These tall, thick clouds head for North America’s west
coast where they forcefully release large dumps of
precipitation. The changing cloud patterns observed over the
Pacific between 1984 and 2005 do not correspond to natural
patterns generated by sea surface temperatures, El Niño or East
Asian winter monsoons. Nor are the same changes appearing with
cloud cover over the north Atlantic. Instead, scientists have
traced the cause to human activity in Asia. Besides documenting
a dramatic change in Pacific cloud cover, satellites have also
measured soot and sulphur dioxide levels in the atmosphere over
Asia. As a consequence of expanding industrialization discharge
of these air pollutants has risen shar