Tag Archives: global warming

US West Coast Erosion Spiked In Winter 2009-10, Previewing Likely Future As Climate Changes

SANTA CRUZ, Calif. – Knowing that the U.S. west coast was battered during the winter before last by a climatic pattern expected more often in the future, scientists have now pieced together a San Diego-to-Seattle assessment of the damage wrought by that winter’s extreme waves and higher-than-usual water levels. Getting a better understanding of how the 2009-10 conditions tore away and reshaped shorelines will help coastal experts better predict future changes that may be in store for the Pacific coast, the researchers say.

“The stormy conditions of the 2009-10 El Niño winter eroded the beaches to often unprecedented levels at sites throughout California and vulnerable sites in the Pacific Northwest,” said Patrick Barnard, USGS coastal geologist. In California, for example, winter wave energy was 20 percent above average for the years dating back to 1997, resulting in shoreline erosion that exceeded the average by 36 percent, he and his colleagues found. (more…)

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Warming Ocean Layers Will Undermine Polar Ice Sheets

*The UA-led research, based on climate models, shows that melting of the ice sheets will occur in this century and next.

Warming of the ocean’s subsurface layers will melt underwater portions of the Greenland and Antarctic ice sheets faster than previously thought, according to new University of Arizona-led research. Such melting would increase the sea level more than already projected.

The research, based on 19 state-of-the-art climate models, proposes a new mechanism by which global warming will accelerate the melting of the great ice sheets during this century and the next. (more…)

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Ocean’s Harmful Low-Oxygen Zones growing, are Sensitive to Small Changes in Climate

Fluctuations in climate can drastically affect the habitability of marine ecosystems, according to a new study by UCLA scientists that examined the expansion and contraction of low-oxygen zones in the ocean.

The UCLA research team, led by assistant professor of atmospheric and oceanic sciences Curtis Deutsch, used a specialized computer simulation to demonstrate for the first time that the size of low-oxygen zones created by respiring bacteria is extremely sensitive to changes in depth caused by oscillations in climate. These oxygen-depleted regions, which expand or contract depending on their depth, pose a distinct threat to marine life. (more…)

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With Global Warming, Arctic Access Will Diminish By Land But Improve By Sea

Global warming over the next 40 years will cut through Arctic transportation networks like a double-edged sword, limiting access in certain areas and vastly increasing it in others, a new UCLA study predicts.

“As sea ice continues to melt, accessibility by sea will increase, but the viability of an important network of roads that depend on freezing temperatures is threatened by a warming climate,” said Scott Stephenson, a UCLA graduate student in geography and the study’s lead author. (more…)

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Climate Change From Black Carbon Depends on Altitude

Palo Alto, CA — Scientists have known for decades that black carbon aerosols add to global warming. These airborne particles made of sooty carbon are believed to be among the largest man-made contributors to global warming because they absorb solar radiation and heat the atmosphere. New research from Carnegie’s Long Cao and Ken Caldeira, along with colleagues George Ban-Weiss and Govindasamy Bala, quantifies how black carbon’s impact on climate depends on its altitude in the atmosphere. Their work, published online by the journal Climate Dynamics, could have important implications for combating global climate change. (more…)

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Think Globally, but Act Locally When Studying Plants, Animals, Global Warming, Researchers Advise

AUSTIN, Texas — Global warming is clearly affecting plants and animals, but we should not try to tease apart the specific contribution of greenhouse gas driven climate change to extinctions or declines of species at local scales, biologists from The University of Texas at Austin advise.

Camille Parmesan, Michael C. Singer and their coauthors published their commentary online this week in Nature Climate Change.

“Yes, global warming is happening. Yes, it is caused by human activities. And yes, we’ve clearly shown that species are impacted by global warming on a global scale,” says Parmesan, associate professor of integrative biology. (more…)

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