
Western US’s Stronger Storms Traced to Asia Pollution
Winter cyclones may be gaining intensity as they pick up soot and other particles, says a US research team.
March 12, 2007
What happens in one’s country, does not necessarily stay in that country. Researchers have been studying the burning of coal in China and the effects it has on the other side of the world. They have noted that tiny particles of soot from the coal combustion process has vast impacts on the weather in North America, particularly the frequency and strength of its storms and cyclones. Furthermore, experts are very concerned that the industrialization of China along with its increasing hunger for coal-derived energy will only further escalate the problem. Experts believe that clean coal technologies are the answer to this global crisis. Airborne Clean Energy is the answer to this global pollution problem. Its clean coal technologies remove virtually all the pollution from coal burning power plant.
The following is the relative information from the article “Western US’s Stronger Storms Traced to Asia Pollution” by Peter N. Spotts.
Air pollution blowing over the western US from Asia has been a growing environmental concern for several years. Now, it seems, it's giving winter storms added punch as well.
Tiny aerosols and soot from burning wood and coal in winter, especially in China, appear to be seeding clouds in large winter storms that churn thousands of miles east across the northern Pacific, says a team of US scientists. The pollution is turning relatively routine marine rain clouds into towering thunderheads, much like those seen above land.
Previous studies have shown that during the last half of the 20th century, northern Pacific winter storms have become steadily more frequent and stronger, based on tracking wind speeds and atmospheric pressure. The latest results, published last week, indicate that ill winds blowing out of Asia are adding muscle to the types of clouds these stronger winter cyclones carry.
The team posits that the shift toward these types of clouds, with their strong updrafts, could be altering global circulation patterns – perhaps even masking the effects of global warming, because the thicker, taller clouds reflect more sunlight back into space. And they could be contributing to more rapid melting of snow and ice in the Arctic as dark soot is lofted by strong updrafts in these clouds and carried north to fall back to the surface.
Others have noted this effect of smoke and soot on individual thunderstorms in the Amazon. But this is the first time researchers have seen the effect on storm systems hundreds of miles across.
"As you change things in the atmosphere, whether it's particulates or climate change, all of the effects are not obvious" immediately, says Renyi Zhang, an atmospheric scientist at Texas A&M University in College Station, who led the study.
A POOR GRASP ON AEROSOLS' EFFECTS
The team has long been interested in the effects soot and tiny particles called aerosols have on climate. The latest report on global-warming science from the Intergovernmental Panel on Climate Change, released last month, shows that researchers have a poor grasp on these effects. Of all the agents affecting climate – sunlight, greenhouse gases, mineral dust blowing around, for example – the "indirect" effect aerosols have on climate through seeding clouds remains the largest source of uncertainty the report lists. The US and Europe have imposed tough air-pollution laws, and, indeed, no such cloud trends were seen over the north Atlantic during the study period. Asian countries, with their rapidly growing economies, have been slow to follow suit.
For this study, the scientists used satellite photos of winter storm clouds from two sets of satellites. They used images taken throughout each January between 1984 and 2005.
Then they compared cloud information averaged over the first 10 years with cloud data from the second 10 years. The number of so-called deep convective clouds – driven by strong updrafts and typical of intense thunderstorms – rose by 20 to 50 percent over much of the region. Then the team used one of the latest computer models capable of simulating cloud activity to test the notion that aerosols might be driving the change.
The team found a marked increase in deep convective clouds when the aerosols were included. Cloud formation reverted to more normal types when aerosols were left out of the calculations.
Some researchers say the team's explanation for the increase in convective clouds is plausible. But they also note that the physical processes involved challenge the ability of computer models to simulate them.
WIND PATTERNS ARE CHANGING
Still, the results imply a one-two punch, adds Henry Diaz, an atmospheric scientist at the National Oceanic and Atmospheric Administration's Earth System Research Laboratory in Boulder, Colo.
Long-term changes in large-scale wind patterns in the north Pacific, driven by rising ocean temperatures in the tropics, appear to be "forcing more intense cyclones, and those are better able to use the particulates to enhance themselves," he says.
Aerosols' effects, however, may be on the decline. Last year, China adopted a five-year plan than calls for a 20 percent reduction in sulfur-dioxide emissions by 2010.
The full text of the above article can be found at the following websites:
http://www.csmonitor.com/2007/0312/p02s01-sten.html
http://www.csmonitor.com/2007/0312/p02s01-sten.html?page=2
|