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Cars Emerge as Key Atmospheric Warming Force: Study

http://pda.physorg.com/climate-warming-aerosols_news185807209.html

For decades, climatologists have studied the gases and particles that have potential to alter Earth's climate. They have discovered and described certain airborne chemicals that can trap incoming sunlight and warm the climate, while others cool the planet by blocking the Sun's rays.

Now a new study led by Nadine Unger of NASA's Goddard Institute for Space Studies (GISS) in New York City offers a more intuitive way to understand what's changing the Earth's climate. Rather than analyzing impacts by chemical species, scientists have analyzed the climate impacts by different economic sectors.

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In their analysis, motor vehicles emerged as the greatest contributor to atmospheric warming now and in the near term. Cars, buses, and trucks release pollutants and greenhouse gases that promote warming, while emitting few aerosols that counteract it.

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Warmer planet temperatures could cause longer-lasting weather patterns

http://pda.physorg.com/blocking-blockingevents-atmosphericblocking_news185719909.html

Whether it's never-ending heat waves or winter storms, atmospheric blocking can have a significant impact on local agriculture, business and the environment. Although these stagnant weather patterns are often difficult to predict, University of Missouri researchers are now studying whether increasing planet temperatures and carbon dioxide levels could lead to atmospheric blocking and when this blocking might occur, leading to more accurate forecasts.

"In this research, we're trying to see if increased carbon dioxide in the atmosphere and the resulting atmospheric warming will affect the onset and duration of future blocking events," said Tony Lupo, professor and chair of the atmospheric science department at the MU College of Agriculture, Food and Natural Resources. "We're hoping that the research will add cues that could help fellow forecasters better predict blocking and warn people in cases of long-lasting, severe weather."

Atmospheric blocking occurs between 20-40 times each year and usually lasts between 8-11 days, Lupo said. Although they are one of the rarest weather events, blocking can trigger dangerous conditions, such as a 2003 European heat wave that caused 40,000 deaths. Blocking usually results when a powerful, high-pressure area gets stuck in one place and, because they cover a large area, fronts behind them are blocked. Lupo believes that heat sources, such as radiation, condensation, and surface heating and cooling, have a significant role in a blocking's onset and duration. Therefore, planetary warming could increase the frequency and impact of atmospheric blocking.

"It is anticipated that in a warmer world, blocking events will be more numerous, weaker and longer-lived," Lupo said. "This could result in an environment with more storms. We also anticipate the variability of weather patterns will change dramatically over some parts of the world, such as North America, Europe and Asia, but not in others."

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Ocean geoengineering scheme no easy fix for global warming

http://pda.physorg.com/carbondioxide-globalwarming-carbon_news185710063.html

Pumping nutrient-rich water up from the deep ocean to boost algal growth in sunlit surface waters and draw carbon dioxide down from the atmosphere has been touted as a way of ameliorating global warming. However, a new study led by Professor Andreas Oschlies of the Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel, Germany, pours cold water on the idea.

"Computer simulations show that climatic benefits of the proposed geo-engineering scheme would be modest, with the potential to exacerbate global warming should it fail," said study co-author Dr Andrew Yool of the National Oceanography Centre, Southampton (NOCS).

If international governmental policies fail to reduce emissions of carbon dioxide to levels needed to keep the impacts of human-induced climate change within acceptable limits it may necessary to move to 'Plan B'. This could involve the implementation of one or more large-scale geo-engineering schemes proposed for reducing the carbon dioxide increase in the atmosphere.

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Soil contributes to climate warming more than expected

http://www.physorg.com/news184925284.html

The climatic warming will increase the carbon dioxide emissions from soil more than previously estimated. This is a mechanism that will significantly accelerate the climate change. Already now the carbon dioxide emissions from soil are ten times higher than the emissions of fossil carbon. A Finnish research group has proved that the present standard measurements underestimate the effect of climate warming on emissions from the soil.

The error is serious enough to require revisions in climate change estimates. In all climate models, the estimates of emissions from soil are based on measurements made using this erroneous method. Climate models must be revised so that the largest carbon storage of the land ecosystems will be estimated correctly. The sensitivity of the soil carbon storage to climatic warming will endanger the carbon sink capacity of forests in the future.

Research on the effect of climate change on the carbon dioxide release from soil is seriously studied by many research groups around the world. It is known that emissions from soil have a significant influence on the carbon dioxide concentration in the atmosphere and thereby on the future climate. However, these studies are usually based on short-term measurements of the carbon dioxide production of soil. According to the results of the Finnish research group, such a method gives systematically biased estimates on the effects of climate change on the emissions.

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"The studies in boreal forests showed that carbon dioxide emissions from the soil will be up to 50 percent higher than those suggested by the present mainstream method, if the mean temperature will rise as it is estimated, that is, by 5 centigrades before the end of this century, and if the carbon flow to the soil will not increase."

That certainly confirms it.
 
Ice shelves disappearing on Antarctic Peninsula

http://pda.physorg.com/ice-iceshelves-antarctic_news186068531.html

Ice shelves are retreating in the southern section of the Antarctic Peninsula due to climate change. This could result in glacier retreat and sea-level rise if warming continues, threatening coastal communities and low-lying islands worldwide.

Research by the U.S. Geological Survey is the first to document that every ice front in the southern part of the Antarctic Peninsula has been retreating overall from 1947 to 2009, with the most dramatic changes occurring since 1990. The USGS previously documented that the majority of ice fronts on the entire Peninsula have also retreated during the late 20th century and into the early 21st century.

The ice shelves are attached to the continent and already floating, holding in place the Antarctic ice sheet that covers about 98 percent of the Antarctic continent. As the ice shelves break off, it is easier for outlet glaciers and ice streams from the ice sheet to flow into the sea. The transition of that ice from land to the ocean is what raises sea level.

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Deep in sediments off Antarctica, Stanford scientists find insight into past ...

Deep in sediments off Antarctica, Stanford scientists find insight into past -- and possible future -- climates

http://pda.physorg.com/sealevel-icesheet-ice_news185729199.html

From the Antarctic Ocean, Earth scientist Rob Dunbar blogs about the challenges of drilling ancient deep-sea sediments -- and what he's found in them.

If cabin fever is gnawing at you this winter, consider taking a vicarious voyage with Stanford Earth scientist Rob Dunbar, who is drilling in - and blogging from - the deep sea off the East Antarctic Ice Sheet. He's in search of clues to Earth's past climate, and his blog, full of video clips, photos and written entries, gives a lively account of an expedition to Wilkes Land, an area due south of Australia that has never been drilled before.

Dunbar and his fellow researchers are extracting cores of sediment from deposits under the ocean that were laid down over the last 50 million years or so, stretching back to a time when a balmier Antarctica was largely ice free and covered with forests. The team particularly wants to analyze sediments deposited about 34 million years ago, during the transition from that warm climate to a cooler one that produced the first growth of polar ice caps.

Dunbar said the transition is thought to have been triggered by changes in the levels of carbon dioxide and other greenhouse gases in the atmosphere. "Learning more about abrupt climate transitions in the past will help us better understand what lies ahead in our greenhouse future," he said.
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Marine Scientist Finds 'Little Ice Age' Had Dramatic Effect on Gulf

http://pda.physorg.com/climatechange-climate-iceage_news186089477.html

More than 350 years ago, the temperatures in northern Europe dropped dramatically in an event known as the “Little Ice Age.” Now - deep below the waters of the Gulf of Mexico and buried in the sand, silt and mud - a USF marine geologist has discovered new evidence showing just how this long-ago climate change also affected the low latitude of subtropical areas.

Using deep-sea sediment samples pulled from below the gulf floor, climate change researcher Julie Richey has been able to reconstruct what happened to temperatures on the gulf’s surface. Her discovery: the Gulf of Mexico cooled 2 to 3-degrees during the Little Ice Age, a much more dramatic effect that suggests the region may be more sensitive to climate change than scientists expected.

“The more we learn about past climate change, the more we understand about what is occurring now,” said Richey, a presidential doctoral fellow at the College of Marine Science.

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I thought the Little Ice Age was disproved by the Hockey Stick?


The little ice age is readily apparent in all the climate reconstitution. It is, however, much smaller then the blade of the hockey stick. For some strange reason anti-science blogger seem to think that if the LIA exists it must be larger then recent climate change.

in keeping with the purpose of this thread to discuss actual published science not loony blogsphere pseudo-science here is the most comprehensive climate reconstruction to date.

http://www.pnas.org/content/early/2008/09/02/0805721105.full.pdf+html
 
Some posts moved to AAH. Please keep discussion centred on the studies posted in this thread. There are plenty of other threads for general AGW debate. Thank you for your cooperation
Replying to this modbox in thread will be off topic  Posted By: Professor Yaffle
 
Two huge icebergs let loose off Antarctica's coast

http://pda.physorg.com/water-glacier-oxygen_news186387978.html

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The new iceberg is 48 miles (78 kilometers) long and about 24 miles (39 kilometers) wide and holds roughly the equivalent of a fifth of the world's annual total water usage, Young told The Associated Press.

Experts are concerned about the effect of the massive displacement of ice on the ice-free water next to the glacier, which is important for ocean currents.

This area of water had been kept clear because of the glacier, said Steve Rintoul, a leading climate expert. With part of the glacier gone, the area could fill with sea ice, which would disrupt the ability for the dense and cold water to sink.

This sinking water is what spills into ocean basins and feeds the global ocean currents with oxygen, Rintoul explained.

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Coffee hit by global warming say growers

http://pda.physorg.com/coffee-producers-countries_news186418664.html

Coffee producers say they are getting hammered by global warming, with higher temperatures forcing growers to move to prized higher ground, putting the cash crop at risk.

"There is already evidence of important changes" said Nestor Osorio, head of the International Coffee Organization (ICO), which represents 77 countries that export or import the beans.

"In the last 25 years the temperature has risen half a degree in coffee producing countries, five times more than in the 25 years before," he said.

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http://pda.physorg.com/ice-iceloss-glaciermelt_news186758202.html

http://pda.physorg.com/ice-iceloss-glaciermelt_news186758202.html

The melting of glaciers is well documented, but when looking at the rate at which they have been retreating, a team of international researchers steps back and says not so fast.
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Schiefer said melting glaciers in Alaska originally were thought to contribute about .0067 inches to sea-level rise per year. The team's new calculations put that number closer to .0047 inches per year. The numbers sound small, but as Schiefer said, "It adds up over the decades."
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While the team determined a lower rate of glacial melt during a greater than 40-year span, Schiefer said other studies have demonstrated the rate of ice loss has more than doubled in just the last two decades.

"With current projections of climate change, we expect that acceleration to continue," Schiefer said. This substantial increase in ice loss since the 1990s is now pushing up the rise in sea level to between .0098 inches and .0118 inches per year—more than double the average rate for the last 40 years.

So, the good news; Not as much contribution over the last 40 years as believed from smaller studies. The bad news; its accelerating.
 
Old diving tank air extends CSIRO Air Archive

http://pda.physorg.com/air-capegrim-greenhousegases_news186833230.html

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According to the diving diary of the SCUBA tank's owner, Mr J. Allport of Beaumaris, the tank was last filled in 1968 and last used in 1970. A diving service company in Melbourne's CBD filled the tank and it therefore contains ambient air from the city precinct.

Analysis of the air sample using a range of detectors has generated new trace gas data on; propellants, refrigerants and aluminium smelter emissions (HFCS and PFCs), present in the global background atmosphere of 1968, but not widely used in Melbourne at that time.

"If tanks were filled in a clean coastal environment their usefulness in measuring greenhouse gases such as carbon dioxide, methane, nitrous oxide and chloro-flurocarbons (CFCs) is much broader," Dr Fraser said.
 
http://news.bbc.co.uk/1/hi/sci/tech/8550090.stm

A review from the UK Met Office says it is becoming clearer that human activities are causing climate change.

It says the evidence is stronger now than when the Intergovernmental Panel on Climate Change carried out its last assessment in 2007.

The analysis, published in the Wiley Interdisciplinary Reviews Climate Change Journal, has assessed 110 research papers on the subject. [...]

The study, which looks at research published since the IPCC's report, has found that changes in Arctic sea ice, atmospheric moisture, saltiness of parts of the Atlantic Ocean and temperature changes in the Antarctic are consistent with human influence on our climate.

Guardian report on the same study: http://www.guardian.co.uk/environment/2010/mar/05/met-office-analysis-climate-change

The map at the end of the article is interesting.
 
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Aquatic 'dead zones' contributing to climate change

http://pda.physorg.com/nitrousoxide-waters-production_news187537818.html

The increased frequency and intensity of oxygen-deprived "dead zones" along the world's coasts can negatively impact environmental conditions in far more than just local waters. In the March 12 edition of the journal Science, University of Maryland Center for Environmental Science oceanographer Dr. Lou Codispoti explains that the increased amount of nitrous oxide (N2O) produced in low-oxygen (hypoxic) waters can elevate concentrations in the atmosphere, further exacerbating the impacts of global warming and contributing to ozone "holes" that cause an increase in our exposure to harmful UV radiation.

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