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Climate: New ice core record shows three distinct CO2 pulses about 10,000 years ago, as ice age ended

‘The natural carbon cycle can change a lot faster than we thought’

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How will Earth’s climate respond to the current rise in CO2?

Staff Report

FRISCO — One of the most detailed ice cores samples ever taken from Antarctica shows three sharp spikes of atmospheric carbon dioxide ushering in the end of the ice age about 10,000 years ago.

Based on the findings, the researchers said that the increase in atmospheric CO2 from the peak of the last ice age to complete deglaciation was about 80 parts per million, taking place over 10,000 years, with about half that increase occurring in just a few centuries.

They’re not sure what caused the sudden surges, but suspect it was a combination of factors, including ocean circulation, changing wind patterns, and terrestrial processes. But understanding the mechanisms that caused the changes would help determine what take the Earth in and out of ice age regimes. Continue reading

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Climate: Ocean acidification may be stunting coral growth

Mapping coral diseases is helping researchers determine the cause. Photo courtesy NOAA.

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?

Staff Report

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

Climate: Cut carbon, stream your movies online

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Study finds that online movie viewing is more energy efficient

Staff Report

FRISCO —All those trips to the video store and Red Box, and all the fossil fuel used to manufacture and transport DVDs and CDs added up to more than 4 billion pounds of carbon dioxide emissions that could have been avoided (in 2011) if all media were simply streamed online, scientists concluded after taking a close look at the carbon budget of the entertainment business.

The study, published May 29 in the journal Environmental Research Letters, says more energy efficient electronic devices have tipped the balance toward online consumption of movies and music. A significant proportion of the energy consumption and carbon emissions for streaming comes from the transmission of data, which increases drastically when more complex, high-definition content is streamed. Continue reading

Study: CO2 buildup could affect food quality

Wheat field in Upper Austria

A wheat field in Upper Austria ripens under a summer sun. bberwyn photo.

Protein levels in key grains could decline by 3 percent

Staff Report

FRISCO — Along with cutting yields of some key crops, increasing atmospheric carbon dioxide is also expected to affect the nutritional quality of food crops. Field tests by UC Davis scientists show that elevated levels of carbon dioxide make it harder for some plants to convert nitrogen into proteins.

“Food quality is declining under the rising levels of atmospheric carbon dioxide that we are experiencing,” said lead author Arnold Bloom, a professor in the Department of Plant Sciences at UC Davis. “Several explanations for this decline have been put forward, but this is the first study to demonstrate that elevated carbon dioxide inhibits the conversion of nitrate into protein in a field-grown crop,” Bloom said. Continue reading

Climate: Methane emissions from freshwater ecosystem set to soar as Earth warms

New study assesses freshwater methane on a global scale

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Microorganisms in freshwater ecosystems generate significant amounts of methane.

Staff Report

FRISCO — After recalculating Earth’s greenhouse gas budget, Princeton scientists say that methane emissions will start increasing at a faster pace than carbon dioxide, primarily due to the release of methane from microscopic freshwater organisms.

Methane is about 30 times more effective than CO2 at trapping the sun’s heat, and for every degree of warming, methane emissions will increase several times over, according to the research published in Nature.

Continue reading

Climate: Permafrost thaw doubles carbon losses

Study says greening tundra won’t offset permafrost meltdown

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Study says new plant growth won’t compensate for carbon emissions from melting tundra in the Arctic. bberwyn photo.

Staff Report

FRISCO — Permafrost could dwindle by 30 to 70 percent by the end of the century, and more vegetation in the Arctic won’t be enough to offset the carbon emissions from thawing organic soils.

Scientists with the Woods Hole Research Center reached their conclusions after a series of field tests designed to measure net gains or losses in carbon emissions. The study is published in the journal Ecology.

“Our results show that while permafrost degradation increased carbon uptake during the growing season, in line with decadal trends of ‘greening’ tundra, warming and permafrost thaw also enhanced winter respiration, which doubled annual carbon losses,” said WHRC assistant scientist Sue Natali. Continue reading

Forest fungi help stabilize climate during low CO2 times

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Yet another study shows how fungi may play a key role in regulating carbon.

By Summit Voice

FRISCO — While most current climate research focuses on increasing levels of carbon dioxide, scientists in the UK recently studied long-past eras when CO2 levels were much lower, and discovered a biological mechanism that could explain how the Earth’s atmospheric carbon dioxide and climate were stabilized over the past 24 million years.

When CO2 levels became too low for plants to grow properly, forests appear to have kept the climate in check by slowing down the removal of carbon dioxide from the atmosphere. The report has been published in Biogeosciences, an open access journal of the European Geosciences Union.

“As CO2 concentrations in the atmosphere fall, the Earth loses its greenhouse effect, which can lead to glacial conditions,” said lead-author Joe Quirk, with the University of Sheffield. “Over the last 24 million years, the geologic conditions were such that atmospheric CO2 could have fallen to very low levels … but it did not drop below a minimum concentration of about 180 to 200 parts per million. Why?” Continue reading

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