Climate Change May Lead To Bumpier Airplane Rides, Study Finds

Climate Change May Lead To Bumpier Airplane Rides, Study Finds
POPULAR SCIENCE – NEW TECHNOLOGY, SCIENCE NEWS, THE FUTURE NOW | APRIL 8, 2013
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The first study of global warming’s effects on clear-air turbulence offers some uncomfortable predictions.

By 2050, plane trips between the U.S. and Europe could take longer, use more fuel and be subject to more turbulence, according to a new study.

The study investigated clear-air turbulence, or turbulence that occurs in clear sky instead of inside clouds or near mountains. Clear-air turbulence is impossible for pilots to spot or radar to detect, but models do exist to predict where and when it will occur. Two climate researchers in the U.K. combined different models to come up with a calculation for how a doubling in atmospheric carbon dioxide levels, compared to pre-industrial levels, could affect clear-air turbulence. (In one of the Intergovernmental Panel on Climate Change’s four possible future scenarios for climate change, carbon dioxide levels double by the middle of the 21st century.)

In the new hybrid model, twice as much carbon dioxide in the air would increase median clear-air turbulence strength along common transatlantic routes by 41 percent. Turbulence of at least moderate severity would happen 40 percent to 170 percent more often. Carbon dioxide increases strengthen jet streams, which are a major driving factor in clear-air turbulence.

Airline passengers won’t necessarily feel these exact numbers, as what passengers feel is mostly that stomach-dropping, up-and-down turbulence, which doesn’t always increase linearly with overall turbulence. Nevertheless, New York-to-London will probably get bumpier. The U.K. researchers cited two observational studies that suggested that transatlantic flights are already more turbulent than they used to be.

The researchers said avoiding increased turbulence spots could account for increased passenger jet fuel use and flight times.

This is the first time anyone has studied how global warming will affect clear-air turbulence, the researchers wrote in their paper,published today in the journal Nature Climate Change

By 2050, Arctic to be warmer and greener

By 2050, Arctic to be warmer and greener
TECHNOLOGY & SCIENCE | APRIL 4, 2013
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By Tia Ghose
LiveScience

Large swaths of the Arctic tundra will be warm enough to support lush vegetation and trees by 2050, a new study suggests.

Higher temperatures will lessen snow cover, according to the study, which is detailed in the March 31 issue of the journal Nature Climate Change. That, in turn, will decrease the sunlight reflected back into the atmosphere and increase warming. About half the areas will see vegetation change, and areas currently populated by shrubs may find woody trees taking their place.

More on warming from NBCNews.com:

Product picked from Greenland tundra

Arctic gets greener as climate warms up

“Substitute the snowy surface with the darker surface of a coniferous tree, and the darker surface stores more heat,” said study co-author Pieter Beck, a vegetative ecologist at the Woods Hole Research Center in Massachusetts. “It’s going to exacerbate warming.”

Warming Arctic
The Arctic climate affects the world: Changes in sea ice affect ocean circulation, which, in turn, affects atmospheric circulation that then impacts the globe, said Bruce Forbes, a geographer at the Arctic Center at the University of Lapland in Finland, who was not involved in the study. [Images of Melt: Earth’s Vanishing Ice]

Past research suggested that warming has already brought later winters and earlier springs to the Arctic. And fossil forests reveal the Arctic was once green as well.

To find out exactly how much greening Arctic warming would bring, the team used a model that projected how temperature changes would affect snow cover, vegetation and the increased evaporation and transpiration from plants in the Arctic.

Transformed tundra
The team found that at least half of the tundra would see changes in the plant types it supported by 2050. In addition, they found more than a 50 percent increase in how much woody greenery — such as coniferous trees — would populate the Arctic. The tree line would also shift north, with coniferous forests sprouting where shrubs once grew.

Most of the greening was driven by the loss of reflectivity, or albedo, from snow cover. With less snow to reflect heat back into the atmosphere and more dark trees, the Earth gets warmer, “just like a dark car gets hotter in a warm parking lot than a light car does,” Beck told LiveScience.

That warmth supports more tree and shrub growth, creating a positive feedback cycle to the warming, Beck said.

Real effect
The findings match forecasts for Arctic greening predicted by various other methods, and they foreshadow effects that will strike closer to home later, Forbes said.

“What’s happening now in the Arctic is a faster version of what will be happening at lower latitudes,” Forbes told LiveScience.

That could worsen extreme weather events like Hurricane Sandy in the future.

“The snowstorms in Washington, D.C., and New York, and the flooding and the freezing on the River Thames — the extreme weather will continue to be extreme but it won’t be so uncommon,” Forbes said…. Read more