Posted on September 17, 2014 by Bob Berwyn
Coral growth is slowing dramatically along parts of the Great Barrier Reef. Photo courtesy NOAA.
Will the world’s coral reefs simply dissolve as oceans become more acidic?
FRISCO — Scientists monitoring the Great Barrier Reef said they’ve tracked a “perilous” 40 percent slowdown in coral growth rates since the 1970s.
The trend may be linked with increasing ocean acidification, according to the new study led by researchers with the Carnegie Institution for Science.
The researchers compared current measurements of the growth rate of a section of Australia’s Great Barrier Reef with similar measurements taken more than 30 years ago. Continue reading
Filed under: biodiversity, climate and weather, coral reefs, Environment, global warming, ocean acidification | Tagged: carbon dioxide, climate change, CO2, coral reefs, greenhouse gases, ocean acidification | Leave a comment »
Posted on September 8, 2014 by Bob Berwyn
U.S. airlines have long lobbied against any measures aimed at cutting greenhouse gas emissions from aircraft, but they won’t be able to dodge new EPA pollution regulations developed under the authority of the Clean Air Act.
Agency targets spring 2016 to make initial findings
By Bob Berwyn
FRISCO — U.S. airlines may soon be required to at least start thinking about cutting their carbon footprint.
Aviation accounts for about 11 percent of carbon dioxide emissions from the U.S. transportation sector and is one of the fastest-growing sources of carbon pollution, rising between 3 percent to 5 percent a year. Carbon emissions from global aviation will quadruple by mid-century without action. Continue reading
Filed under: air quality, climate and weather, Environment, global warming | Tagged: air pollution, airlines, climate change, EPA, greenhouse gases | 5 Comments »
Posted on September 1, 2014 by Bob Berwyn
Taking a lunch break during a search for orchids in the Austrian countryside.
‘Agricultural practices are not necessarily at fault here – but our choice of food is’
FRISCO — Forget about greenhouse gas pollution from factories and transportation — by 2050 emissions of carbon dioxide and methane from food production alone could exceed targets set to prevent catastrophic global warming, University of Cambridge scientists warn in a new paper.
A major shift in food consumption norms has to be a big part of an overall plan to cut atmospheric concentrations of heat-trapping air pollution, especially given the current trend toward meat-heavy Western diets, the authors wrote in the journal Nature Climate Change. Continue reading
Filed under: agriculture, climate and weather, Environment, global warming | Tagged: climate change, Environment, global food production, global warming, greenhouse gases | 2 Comments »
Posted on August 27, 2014 by Bob Berwyn
Odds of 30-year dry spells increase dramatically as global temps rise
Green bars indicate wet periods, the larger the bar the more unusually wet. In a similar way, yellow indicates dry and droughty periods. The graph stretches from January 1895 on the left to last month on the right, showing how the cycle of droughts alternating with wet years has changed, with dry years becoming more prevalent.
By Summit Voice
FRISCO — Tree ring records clearly show that the southwestern U.S. experienced megadroughts long before the anthropogenic global warming era. One such decades-long dry spell may have been a factor in the collapse of the Anasazi civilization at Mesa Verde.
But the steady buildup of heat-trapping gases in the atmosphere is loading the dice in favor of another megadrought sooner, rather later, according to scientists with Cornell University, the University of Arizona and U.S. Geological Survey. The chances of a decade-long drought is now at least 50 percent, and there’s a 20 percent to 50 percent chance of a 30-year megadrought.
“For the southwestern U.S., I’m not optimistic about avoiding real megadroughts,” said Toby Ault, Cornell assistant professor of earth and atmospheric sciences and lead author of the paper. “As we add greenhouse gases into the atmosphere – and we haven’t put the brakes on stopping this – we are weighting the dice for megadrought conditions.” Continue reading
Filed under: climate and weather, Drought, extreme weather, global warming | Tagged: Arizona, California drought, climate change, global warming, greenhouse gases, megadrought, New Mexico, Southwest | 1 Comment »
Posted on August 18, 2014 by Bob Berwyn
‘In our data we find unambiguous evidence of anthropogenic contribution to glacier mass loss’
Shrinking glaciers on the Dachstein Mountains in Austria will affect water supplies far downstream in local areas and in distant rivers. bberwyn photo.
FRISCO — Some of the world’s glaciers were shrinking before the onset of unchecked heat-trapping pollution, but the human factor in the glacial equation has grown exponentially in the past few decades.
A new modeling study led by scientists at the University of Innsbruck (Austria) shows that only about 25 percent of the global glacier mass loss during the period of 1851 to 2010 is attributable to anthropogenic causes. However, between 1991 and 2010 the fraction increased to about two-thirds.
“In the 19th and first half of 20th century we observed that glacier mass loss attributable to human activity is hardly noticeable but since then has steadily increased,” said researcher Ben Marzeion, explaining that scaled-down regional models can detect an anthropogenic influence in America and the Alps, where glacier changes are particularly well documented. Continue reading
Filed under: climate and weather, Environment | Tagged: climate, Environment, glaciers, global warming, greenhouse gases, mountains, water | Leave a comment »
Posted on July 30, 2014 by Bob Berwyn
Cutting methane could slow global temperature surge.
Action could help avert climate tipping points
FRISCO — Leading scientists say the U.S. must do more to cut methane emissions from fossil fuel exploitation and other sectors to try and avoid reaching climate tipping points that could have disastrous implications.
Methane is a much more potent heat-trapping gas than carbon dioxide, but it only stays in the atmosphere for about 12 years, which means that big cuts could have a tangible short-term benefit in the race to cap global warming. Continue reading
Filed under: climate and weather, energy, Environment, global warming, greenhouse gases | Tagged: climate change, Environment, global warming, greenhouse gases, methane | Leave a comment »