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Post Info TOPIC: Greenhouse Gases


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Posts: 131433
Date:
Stronger hurricanes
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 Atmospheric scientists have uncovered fresh evidence to support the hotly debated theory that global warming has contributed to the emergence of stronger hurricanes in the Atlantic Ocean.
The unsettling trend is confined to the Atlantic, however, and does not hold up in any of the world's other oceans, researchers have also found.
Scientists at the University of Wisconsin-Madison and the National Climatic Data Centre (NCDC) of the National Oceanic and Atmospheric Administration reported the finding in the journal Geophysical Research Letters. The work should help resolve some of the controversy that has swirled around two prominent studies that drew connections last year between global warming and the onset of increasingly intense hurricanes.

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RE: Greenhouse Gases
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 To most people, soil is just dirt. But to microbiologists, it is a veritable zoo of bacteria, fungi and nematodes. It's also a vast carbon dioxide factory. As these microorganisms consume carbon-based materials found in soil, they release carbon dioxide gas into the atmosphere as a normal part of their metabolism.
As the world gets warmer, they'll likely be cranking it out faster than ever.

"As the climate warms, it is predicted that soil carbon is going to be decomposed faster by soil microbes, which means more carbon dioxide is going to be released into the atmosphere. So, there is a very real possibility that you might get this vicious cycle - a positive feedback loop - where increased warming causes more carbon dioxide (to be released from the soil), which causes even more warming" - Teri Balser, assistant professor of soil science at the University of Wisconsin-Madison College of Agricultural and Life Sciences.

Current climate models mostly ignore the specific role that soil microbes play in the release of carbon dioxide into the atmosphere. The information they do include is often based on assumptions that have never been tested in the field, and may be wrong or overly simplistic.
Balser hopes to change that. She recently received a career award from the National Science Foundation to help generate the data needed to correctly account for the role of soil microbes in climate change models.

"Even a tiny change in the amount of carbon in the soil (due to soil microbe activity) could really influence atmospheric carbon dioxide levels" - Teri Balser.

With her new NSF grant award, Balser plans to test the effects of climate change on various microbial communities.
In one experiment, Balser will collect soil samples from northern Wisconsin, and then move half of each sample to southern Wisconsin, where the temperature is slightly warmer. Then, she will compare carbon dioxide released by the same microbial communities at the two different latitudes.
In a second experiment, Balser plans to remove soil cores from the earth, and then replace them upside-down in the same place. In this case, the soil microbes that were previously deeper underground where the temperature is relatively steady will be exposed to the fluctuating temperatures found near the surface. Again, she will look for changes in volumes of carbon dioxide released by the microbes.
Balser will also explore the types of carbon consumed by the microbes. More than 90 percent of soil carbon is stored in a "stable" form that is relatively difficult for microbes to utilise.

"We want to keep carbon in the soil, and not have it released into the atmosphere. The more complex the carbon molecule, the more likely it is to stay in the soil. (So) we don't want soil microbes using complex carbon" - Teri Balser.

Current climate models that do include soil microbe factors assume that as temperatures rise, microbes will utilise more of the stable carbon stored in the ground. These predictions are based on common laws of chemistry.
However, Balser's preliminary data suggest that this assumption is faulty.

"When you look at the physiology of soil microbes in the ground, you get the opposite result of what climate modellers are assuming. We saw that when the temperature went up, the utilization of simple carbon increased and the utilization of complex, difficult-to-use carbon decreased" - Teri Balser.

This result doesn't surprise Balser. Microbes are more than a collection of chemical reactions, she points out. They are biological creatures that behave according to their biological imperatives.

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L

Posts: 131433
Date:
Gas Hydrates
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Scientists Gather Valuable Information On Gas Hydrates
Scientists on the German research ship Sonne have completed the first part of a three-month investigation of gas hydrates under the seafloor off the North Island’s East Coast.
They have successfully used a range of sophisticated instruments to probe deposits of frozen methane beneath the seafloor. The frozen methane is a potential source of natural gas fuel. Scientists are also concerned that these deposits can vaporise under natural conditions and possibly contribute to global warming.

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RE: Greenhouse Gases
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Storing tiny bubbles of carbon dioxide underground could substantially reduce the emission of harmful greenhouse gases says an international team of scientists from Imperial College London, MIT, and Stanford.

In a paper published in a recent issue of Water Resources Research, the scientists describe a mechanism for capturing carbon dioxide emissions from a power plant and injecting the CO2 into the ground. From there it will be trapped naturally as tiny bubbles and safely stored in briny porous rock.
This means, according to the team, that a power plant could have all its CO2 emissions captured and injected underground throughout the life of the plant, and then safely stored over centuries and even millennia. The carbon dioxide eventually would dissolve in the brine and a fraction would adhere to the rock in the form of minerals such as iron and magnesium carbonates.
The researchers consider the possibility of storing CO2 beneath the Earth’s surface in at least three types of geologic formations: depleted oil and gas fields, unminable coal seams, and deep saline aquifers.

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The Senate Commerce Committee's hearing on Climate Change Research and Scientific Integrity
The hearing ended on a very strong note, as Senator John Kerry essentially eviscerated a hapless representative of the Bush administration, acting Climate Change Science Program (CCSP) chairman Bill Brennan [pictured at left]. With Kerry terming the administration's approach to climate change science and policy "the most serious dereliction of public responsibility that I have ever seen," Brennan--who tried to stick with talking points--was massively outgunned.

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Sea level on the rise
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In this five and a half minute podcast, CSIRO's Dr John Church, discusses whether our climate is responding more quickly to rising carbon emissions than previously predicted.

Listen (5140kb, mp3)

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RE: Greenhouse Gases
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At least 300,000 people in north-west China are short of drinking water because of unseasonably warm weather officials say is due to climate change.
Drought hit parts of Shaanxi province after January saw as little as 10% of average rainfall, state media say.
Frozen lakes are melting and trees are blossoming in the capital Beijing as it experiences its warmest winter for 30 years, the China Daily reports.
China is the world's biggest producer of greenhouse gases after the US.

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In releasing its latest comprehensive report, the Intergovernmental Panel on Climate Change (IPCC) focuses an important spotlight on the current state of the Earth’s climate.
Climate change is just one of the many symptoms exhibited by a planet under pressure from human activities.

"Global environmental change, which includes climate change, threatens to irreversibly alter our planet" - Kevin Noone, Executive Director of the International Geosphere-Biosphere Programme (IGBP).

Global studies by IGBP show that human-driven environmental changes are affecting many parts of the Earth’s system, in addition to its climate. For example:

• Half of Earth’s land surface is now domesticated for direct human use.
• 75 percent of the world’s fisheries are fully or over-exploited.
• The composition of today's atmosphere is well outside the range of natural variability the Earth has maintained over the last 650,000 years.
• The Earth is now in the midst of its sixth great extinction event.

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China will spend more to research global warming but lacks the money and technology to significantly reduce the greenhouse gas emissions that are worsening the problem, a government official said Tuesday.
China "lags behind Europe and the United States" in the technology needed to clean its coal, which accounts for 69 percent of its energy output, said Qin Dahe, chief of the China Meteorological Administration.
"It takes time to catch up," said Qin, who served as one of China's representatives to the United Nations Intergovernmental Panel on Climate Change that last week announced that global warming is very likely caused by mankind and will continue for centuries.
Qin's comments at a news conference Tuesday, the first official Chinese response to the report, came as winter temperatures in China's capital hit a 30-year high, state media said.
The China Daily newspaper said Beijing's temperature hit 55 degrees Fahrenheit on Saturday - a 30-year high for the date - prompting an early spring, with frozen lakes melting and trees blooming.
China wants to reduce its dependence on coal but converting to cleaner energies on a mass scale would be prohibitively costly for China, which is still a developing economy.
The lack of technology to clean coal - so it can burn without producing a much pollution - is a serious problem because China is already the world's largest producer and consumer of coal, and is expected to surpass the United States as the world's largest greenhouse gas emitter in the next decade.
Qin said the central government already had set a "very ambitious and arduous goal" of reducing carbon dioxide and other emissions by 4 percent a year over the next five years.

The central government is "very serious about the commitment and has firmly demanded all regions to meet the emissions reduction targets," he said.

However, China has no binding international commitments to reduce its emissions and failed to meet similar targets set by the government five years ago.
A separate Chinese report released last month said climate change will harm China's ecology and economy in the coming decades, possibly causing large drops in agricultural output.
In the latter half of this century production of wheat, corn and rice in China will drop by as much as 37 percent, and the country's average temperatures would rise by 2 or 3 degrees Celsius in the next 50 to 80 years, the report said.
It also said evaporation rates for some inland rivers would increase by 15 percent. China already faces a severe water shortage, especially in the northern part of the country.
A British environmental expert said Monday that water shortages in China already were reaching "incredible" proportions, with Shanghai particularly vulnerable unless drastic action is taken quickly.
Justin Mundy, a government adviser on climate change, pointed to the current low levels of aquifers in Shanghai as a prime example of the problems China faces. Shanghai is going to have to use desalinised water in the next 10 years, then build the infrastructure to import water from Southwest China.

"All the water in the southwest of China is fed by glacial melt. Glacial melt in about 25 years' time is not going to be there in anything like the capacity that is going to be required. What then, Shanghai?"

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The British Geological Survey (BGS) welcomes the Intergovernmental Panel on Climate Change: The Physical Science Basis 4th Assessment Report published on 2 February 2007.
BGS recognises the major contribution that the world's scientists have made to the IPCC. BGS scientists note that it is indisputable that emissions of green house gases from fossil fuels need to be urgently reduced. BGS will continue to deliver the geoscience research and development required to help enable the world to move rapidly to low emission energy technologies especially with respect to CO2 capture and storage from fossil fuels, nuclear and renewable energy.

The IPCC report makes it clear that we have little time left to achieve deep cuts in greenhouse gas emissions. It is vital that the emphasis for R&D, technological deployment and intergovernmental agreements is one of avoiding further risk of damage from fossil fuel emissions to our global atmosphere and oceans, in this narrow time window of opportunity now left to the world. We must also continue to gain better knowledge of the future effects of climate change, so that we can plan ahead- but I doubt we will ever adapt to many of the consequences of global warming and ocean acidification that will arise should we fail to reduce emissions at the appropriate rate. This is, in my view, is the greatest global challenge society has faced. It demands urgent action by everyone" - Dr Nick Riley MBE, Head of Sustainable and Renewable Energy at the British Geological Survey.

Source BGS

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