Could China & India's Air
Pollution be behind our Cold, Snowy Winters?
From: Michaeleen Doucleff, NPR It's March. It's freezing. And there's half a foot of snow on the ground. When is this winter going to end?
Many scientists think that climate
change might be one cause of this year's "snowpocalypse" in Boston
and cold snaps in New York and Washington.
But physicists at NASA's Jet Propulsion Laboratoryhave
been looking into another culprit: air pollution in China and India.
"Over the past 30 years or so, man-made emission centers have shifted from traditional industrialized countries to fast, developing countries in Asia," physicist Jonathan Jiang writes in an email.
The animation from NASA shows how pollution from
Asia and other continents mixes and moves around the world. (It's a simulation
made with satellite data from September 2006 to April 2007.)
The colorful swirls represent
airborne particles in the atmosphere. Many of those particles are sea salt
(shown in blue) picked up from the ocean, and dust (shown in red-orange)
scooped up from deserts.
But there are also man-made
sources of particles. Soot from fires is shown in green-yellow, and sulfur from
fossil fuel emissions and volcanoes is in white.
As the animation moves through
time, you can see fires billow up from South America and parts of Africa. Dust
from the Sahara Desert sweeps west, and power plants in North America and
Europe emit sulfur that blows east.
Then, about 43 seconds into the
video, Asia comes into view. And its coal-powered industrialization is clear.
Large swaths of emissions from
burning coal pulse from China and Southeast Asia in white. Sometimes the
particles blow east and mix with storms above the Pacific Ocean. These storms
can have a big effect on winter weather in the U.S., Jiang says.
Storms in the Pacific move
northwest; some hit the West and cause
rain and snow. Others end up far north in Canada, where they can alter the
weather across the entire U.S., Jiang says.
So what does a bunch of extra
pollution from Asia do to clouds over the Pacific? It makes them bigger and
heavier with more precipitation, Jiang and his colleagues reported last year.
Continue reading at NPR.