Rain

‘Crazy’ climate re-engineering could reduce vital rains, study says

Publication: NBC News   Date: November 1, 2013   View Article

If global warming gases build up so much that record-setting rains, droughts and coastal floods routinely bankrupt businesses and cities, the world’s economic and political powers may decide to aggressively re-engineer the global climate. One option is to fill the atmosphere with enough sunlight-reflecting particles to restore surface temperatures to pre-industrial levels. If they do, would all be cool?

Absolutely not, according to a new study that asked the question to 12 models forced to simulate the global climate with four times more carbon dioxide in the atmosphere than existed in 1850, the start of the industrial revolution. Under such conditions, reflecting sunlight in order to lower temperatures to pre-industrial levels would cause monsoonal rains to drop 5 to 7 percent below pre-industrial levels.

Warming planet could spawn bigger, badder thunderstorms

Publication: NBC News   Date: September 23, 2013   View Article

As the Earth continues to warm during this century, atmospheric conditions ripe for severe thunderstorms and tornadoes will increase in the U.S., according to a new study.

Given the amount of damage caused by the straight-line winds, golf-ball-sized hail or flash floods associated with any given severe thunderstorm, understanding whether they will increase in frequency or intensity on a warming planet is a key question in climate science.

Colorado floods triggered by convergence of geography and climate, experts say

Publication: NBC News   Date: September 17, 2013   View Article

The torrent of water that gushed over and down the Rocky Mountains late last week resulted from a fateful confluence of geography and weather. While the deluge is unprecedented in the historic record, it may offer a window onto the new normal as the planet continues to warm.

The exact role of global climate change in the deluge is uncertain, but it certainly played a part, according to climate, weather and policy experts.

As of Tuesday, more than 17 inches of rain had fallen since Sept. 12 in Boulder, Colo. The soaking, described as “biblical” by the National Weather Service, left at least eight people dead with hundreds more still missing and rendered untold millions of dollars in property damage.

Australia’s sponge effect caused global sea levels to drop, study says

Publication: NBC News   Date: August 19, 2013   View Article

A serendipitous convergence of weather patterns funneled so much water over Australia that normally rising global sea levels actually fell in 2011, according to a new study.

In other words, the rain in Australia stays mainly … out of the ocean.

Unlike other land masses, the soils and topography of Australia are such that the continent acts like a giant sponge, preventing most of the rainfall it receives from quickly running off into the sea.

When it rains: Rising carbon emissions (finally) making world wetter, study says

Publication: NBC News   Date: June 30, 2013   View Article

Keep the rain boots and slickers handy, suggests new research that indicates the world will get wetter as cities rein in air pollution from power plants, factories and cars.

Climate scientists thought global precipitation would rise in step with rising greenhouse gases that are warming the atmosphere, allowing it to hold more water. But that has not occurred, according to Peter Stott, a climate scientist with the Met Office Hadley Center in the United Kingdom.

Photos: Honeycomb Clouds “Communicate,” Rain in Unison

Publication: National Geographic News   Date: August 20, 2010   View Article

Wisps of clouds form a honeycomb-like structure (center) over the Peruvian coast.

Such open-cell marine clouds “communicate” with each other so that they constantly oscillate, or rearrange themselves, in a synchronized pattern, according to a new study from the U.S. National Oceanic and Atmospheric Administration (NOAA).

Inside the thick clouds of the cell walls, water droplets grow, then fall as rain, and the walls dissipate. The raindrops evaporate as they fall, cooling the air, which generates downward air currents.

When the downdrafts hit the ocean surface, they flow outward and collide with each other and “force the air to move upward again” and “form new open cell walls at a different location,” explained study co-author Hailong Wang, a cloud physicist at the Pacific Northwest National Laboratory in Richland, Washington.

Humans Changing Rainfall Patterns, Study Says

Publication: National Geographic News   Date: July 23, 2007   View Article

Humans have caused global precipitation patterns to change substantially over the past century, new research says.

About 1.8 inches (4.5 centimeters) more rain fell annually in Canada, Russia, and Europe in recent years than it did in 1925.

© 2008-2010 Collected Writings By John Roach