Tag Archives: climate

Hazy days of summer: Southeast U.S. field work measures mercury, smog

Dozens of atmospheric scientists, including three University of Washington faculty members, are taking part in what’s being described as one of the largest atmospheric field campaigns in decades.

The six-week Southeast Atmosphere Study, through July 15, includes scientists from more than 30 different institutions. Together they are studying how pollutants combine with natural vegetation emissions to affect climate and air quality in the Southeastern U.S. (more…)

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British butterfly desperate for warm weather this summer

Butterflies are extremely sensitive to changes in temperature and new research has revealed that when summer weather turns bad the silver-spotted skipper battles for survival.

The butterfly, which previously faced extinction from habitat loss, is recovering following conservation efforts but the recent cool wet summers in England have almost stalled its progress.

A 27 year study by researchers at the University of Exeter in collaboration with the University of York, the University of Liverpool, Sussex Wildlife Trust, the Centre for Ecology & Hydrology and the charity Butterfly Conservation has been published in the journal Ecology Letters. The study estimated changes in temperature across a range of silver-spotted skipper habitats and found that localised fluctuations in temperature lead to extreme fluctuations in the butterfly population size and in the probability of the butterflies colonising new sites. (more…)

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In last great age of warmth, CO2 at work — but hardly alone

Warming patterns during Earth’s last period of prolonged global warmth differed dramatically from modern temperature patterns, according to new research by a Yale University scientist and colleagues. Cloud feedbacks, ocean mixing, or other dynamic factors must have played a greater role in Pliocene warming than commonly recognized, the scientists argue, and these must be accounted for in order to make meaningful predictions about Earth’s future climate.

In a paper published April 4 in the journal Nature, Yale climate scientist Alexey Fedorov and colleagues compile records of sea surface temperatures going back five million years, to the early Pliocene. These records reveal a world with fairly uniform warm temperatures in the whole of the Tropics prior to 4 million years ago — a significant scenario that typical climate model simulations fail to show. (more…)

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Dead Forests Release Less Carbon Into Atmosphere Than Expected

Billions of trees killed in the wake of mountain pine beetle infestations, ranging from Mexico to Alaska, have not resulted in a large spike in carbon dioxide released into the atmosphere, contrary to predictions, a UA-led study has found.

Massive tree die-offs release less carbon into the atmosphere than previously thought, new research led by the University of Arizona suggests. 

Across the world, trees are dying in increasing numbers, most likely in the wake of a climate changing toward drier and warmer conditions, scientists suspect. In western North America, outbreaks of mountain pine beetles (Dendroctonus ponderosae) have killed billions of trees from Mexico to Alaska over the last decade.  (more…)

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Volcanic Aerosols, not Pollutants, Tamped down Recent Earth Warming, Says CU Study

A team led by the University of Colorado Boulder looking for clues about why Earth did not warm as much as scientists expected between 2000 and 2010 now thinks the culprits are hiding in plain sight — dozens of volcanoes spewing sulfur dioxide.

The study results essentially exonerate Asia, including India and China, two countries that are estimated to have increased their industrial sulfur dioxide emissions by about 60 percent from 2000 to 2010 through coal burning, said lead study author Ryan Neely, who led the research as part of his CU-Boulder doctoral thesis. Small amounts of sulfur dioxide emissions from Earth’s surface eventually rise 12 to 20 miles into the stratospheric aerosol layer of the atmosphere, where chemical reactions create sulfuric acid and water particles that reflect sunlight back to space, cooling the planet. (more…)

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Climate Change is not an All-or-Nothing Proposition, Researcher Says

BOSTON — An Ohio State University statistician says that the natural human difficulty with grasping probabilities is preventing Americans from dealing with climate change.

In a panel discussion at the American Association for the Advancement of Science meeting on Feb. 15, Mark Berliner said that an aversion to statistical thinking and probability is a significant reason that we haven’t enacted strategies to deal with climate change right now. (more…)

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Lungs of the Planet Reveal Their True Sensitivity to Global Warming

Tropical rainforests are often called the “lungs of the planet” because they generally draw in carbon dioxide and breathe out oxygen. 

But the amount of carbon dioxide that rainforests absorb, or produce, varies hugely with year-to-year variations in the climate.

In a paper published online (Feb 6 2013) by the journal Nature, a team of climate scientists from the University of Exeter, the Met Office-Hadley Centre and the NERC Centre for Ecology & Hydrology, has shown that these variations reveal how vulnerable the rainforest is to climate change. (more…)

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Study Provides New Insights on Drought Predictions in East Africa

Research May Also Help Determine Effects of Global Warming in the Region

With more than 40 million people living under exceptional drought conditions in East Africa, the ability to make accurate predictions of drought has never been more important. In the aftermath of widespread famine and a humanitarian crisis caused by the 2010-2011 drought in the Horn of Africa—possibly the worst drought in 60 years— researchers are striving to determine whether drying trends will continue.

While it is clear that El Niño can affect precipitation in this region of East Africa, very little is known about the drivers of long-term shifts in rainfall. However, new research described in the journal Nature helps explain the mechanisms at work behind historical patterns of aridity in Eastern Africa over many decades, and the findings may help improve future predictions of drought and food security in the region. (more…)

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