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THE SCIENCE OF CLIMATE CHANGE

Below you will find a series of informative articles from various scientific sources on the topic of Climate Change
The material is being provided by GreeningUSA, --  www.greeningusa.org 

"No government can continue good but under the control of the people; and . . . . their minds are to be informed by education what is right and what wrong; to be encouraged in habits of virtue and to be deterred from those of vice . . . . These are the inculcations necessary to render the people a sure basis for the structure and order of government."
Thomas Jefferson

Canadian Arctic Glacier Melt Accelerating, Irreversible, Projections Suggest

http://www.sciencedaily.com/releases/2013/03/130312134914.htm

Mar. 12, 2013 ­ Ongoing glacier loss in the Canadian high Arctic is accelerating and probably irreversible, new model projections by Lenaerts et al. suggest. The Canadian high Arctic is home to the largest clustering of glacier ice outside of Greenland and Antarctica -- 146,000 square kilometers (about 60,000 square miles) of glacier ice spread across 36,000 islands.

In the past few years, the mass of the glaciers in the Canadian Arctic archipelago has begun to plummet. Observations from NASA's Gravity Recovery and Climate Experiment (GRACE) satellites suggest that from 2004 to 2011 the region's glaciers shed approximately 580 gigatons of ice. Aside from glacier calving, which plays only a small role in Canadian glacier mass loss, the drop is due largely to a shift in the surface-mass balance, with warming-induced meltwater runoff outpacing the accumulation of new snowfall.

Using a coupled atmosphere-snow climate model, the authors reproduced the observed changes in glacier mass and sought to forecast projected changes given a future of continued warming. Driving the model with a climate reanalysis dataset for the period 1960 to 2011 and with a potential future warming pathway, the authors find that their model accurately reproduces observed glacier mass losses, including a recent up-tick in the rate of the ice's decline.

The authors calculate that by 2100, when the Arctic archipelago is 6.5 Kelvin (14 degrees Fahrenheit) warmer, the rate of glacier mass loss will be roughly 144 gigatons per year, up from the present rate of 92 gigatons per year. In total, the researchers expect Canadian Arctic archipelago glaciers to lose around 18 percent of their mass by the end of the century. Given current warming trends, they suggest that the ongoing glacier loss is effectively irreversible.
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The above story is reprinted from materials provided by American Geophysical Union, via EurekAlert!, a service of AAAS.

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Journal Reference:

1. Jan T. M. Lenaerts, Jan H. van Angelen, Michiel R. van den Broeke, Alex S. Gardner, Bert Wouters, Erik van Meijgaard. Irreversible mass loss of Canadian Arctic Archipelago glaciers. Geophysical Research Letters, 2013; DOI: 10.1002/grl.50214

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More Storms Like Sandy? Arctic Ice Loss Amplified Superstorm Sandy Violence

http://www.sciencedaily.com/releases/2013/03/130305145133.htm

Mar. 5, 2013 ­ If you believe that last October's Superstorm Sandy was a freak of nature -- the confluence of unusual meteorological, atmospheric and celestial events -- think again.

Cornell and Rutgers researchers report in the March issue of Oceanography that the severe loss of summertime Arctic sea ice -- attributed to greenhouse warming -- appears to enhance Northern Hemisphere jet stream meandering, intensify Arctic air mass invasions toward middle latitudes, and increase the frequency of atmospheric blocking events like the one that steered Hurricane Sandy west into the densely populated New York City area.

The article, "Superstorm Sandy: A Series of Unfortunate Events?" was authored by Charles H. Greene, Cornell professor of earth and atmospheric sciences and director of Cornell's Ocean Resources and Ecosystems program; Jennifer A. Francis of Rutgers University's Institute of Marine and Coastal Sciences; and Bruce C. Monger, Cornell senior research associate, earth and atmospheric sciences.

The researchers assert that the record-breaking sea ice loss from summer 2012, combined with the unusual atmospheric phenomena observed in late October, appear to be linked to global warming.

A strong atmospheric, high-pressure blocking pattern over Greenland and the northwest Atlantic prevented Hurricane Sandy from steering northeast and out to sea like most October hurricanes and tropical storms from the Caribbean. In fact, Sandy traveled up the Atlantic coast and turned left "toward the most populated area along the eastern seaboard" and converged with an extratropical cyclone; this, in turn, fed the weakening Hurricane Sandy and transformed it into a monster tempest.

Superstorm Sandy's extremely low atmospheric pressure and the strong high-pressure block to the north created violent east winds that pushed storm surge against the eastern seaboard. "To literally top it off, the storm surge combined with full-moon high tides and huge ocean waves to produce record high water levels that exceeded the worst-case predictions for parts of New York City," write the researchers.

Greene, Francis and Monger add: "If one accepts this evidence and . . . takes into account the record loss of Arctic sea ice this past September, then perhaps the likelihood of greenhouse warming playing a significant role in Sandy's evolution as an extratropical superstorm is at least as plausible as the idea that this storm was simply a freak of nature."

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The above story is reprinted from materials provided by Cornell University. The original article was written by Blaine Friedlander.

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Sunlight Stimulates Release of Climate-Warming Gas from Melting Arctic Permafrost

http://www.sciencedaily.com/releases/2013/02/130211162116.htm

Feb. 11, 2013 ­ Ancient carbon trapped in Arctic permafrost is extremely sensitive to sunlight and, if exposed to the surface when long-frozen soils melt and collapse, can release climate-warming carbon dioxide gas into the atmosphere much faster than previously thought.

University of Michigan ecologist and aquatic biogeochemist George Kling and his colleagues studied places in Arctic Alaska where permafrost is melting and is causing the overlying land surface to collapse, forming erosional holes and landslides and exposing long-buried soils to sunlight.

They found that sunlight increases bacterial conversion of exposed soil carbon into carbon dioxide gas by at least 40 percent compared to carbon that remains in the dark. The team, led by Rose Cory of the University of North Carolina, reported its findings in an article to be published online Feb. 11 in the Proceedings of the National Academy of Sciences.

"Until now, we didn't really know how reactive this ancient permafrost carbon would be -- whether it would be converted into heat-trapping gases quickly or not," said Kling, a professor in the U-M Department of Ecology and Evolutionary Biology. EEB graduate student Jason Dobkowski is a co-author of the paper.

"What we can say now is that regardless of how fast the thawing of the Arctic permafrost occurs, the conversion of this soil carbon to carbon dioxide and its release into the atmosphere will be faster than we previously thought," Kling said. "That means permafrost carbon is potentially a huge factor that will help determine how fast the Earth warms."

Tremendous stores of organic carbon have been frozen in Arctic permafrost soils for thousands of years. If thawed and released as carbon dioxide gas, this vast carbon repository has the potential to double the amount of the heat-trapping greenhouse gas in the atmosphere on a timescale similar to humanity's inputs of carbon dioxide due to the burning of fossil fuels.

That creates the potential for a positive feedback: As Earth warms due to the human-caused release of heat-trapping gases into the atmosphere, frozen Arctic soils also warm, thaw and release more carbon dioxide. The added carbon dioxide accelerates Earth's warming, which further accelerates the thawing of Arctic soils and the release of even more carbon dioxide. Recent climate change has increased soil temperatures in the Arctic and has thawed large areas of permafrost. Just how much permafrost will thaw in the future and how fast the carbon dioxide will be released is a topic of heated debate among climate scientists.

Already, the melting of ground ice is causing land-surface subsidence features called thermokarst failures. A thermokarst failure is generated when ice-rich, permanently frozen soils are warmed and thawed. As the ice melts, the soil collapses and either creates an erosional hole in the tundra or -- if the slope is steep enough -- a landslide.

Thermokarst failures change the trajectory of the debate on the role of the Arctic in global climate, according to Kling and his colleagues. The unanticipated outcome of the study reported in PNAS is that soil carbon will not be thawed and degraded directly in the soils. Instead, the carbon will be mixed up and exposed to sunlight as the land surface fails.

Sunlight -- and especially ultraviolet radiation, the wavelengths that cause sunburn -- can degrade the organic soil carbon directly to carbon dioxide gas, and sunlight can also alter the carbon to make it a better food for bacteria. When bacteria feed on this carbon, they respire it to carbon dioxide, much the same way that people respire carbon in food and exhale carbon dioxide as a byproduct.

"Whether UV light exposure will enhance or retard the conversion of newly exposed carbon from permafrost soils has been, until recently, anybody's guess," said University of North Carolina's Cory, the study's lead author. "In this research, we provide the first evidence that the respiration of previously frozen soil carbon will be amplified by reactions with sunlight and their effects on bacteria."

"We know that in a warmer world there will be more of these thermokarst failures, and that will lead to more of this ancient frozen carbon being exposed to surface conditions," Kling said. "While we can't say how fast this Arctic carbon will feed back into the global carbon cycle and accelerate climate warming on Earth, the fact that it will be exposed to light means that it will happen faster than we previously thought."

The researchers analyzed water from seven thermokarst failures near Toolik Lake, Alaska, as well as 27 other undisturbed sites nearby.

In addition to Cory, Kling and Dobkowski, Byron Crump of the University of Maryland was a co-author of the PNAS paper. The research was supported by several grants from the National Science Foundation.
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The above story is reprinted from materials provided by University of Michigan.

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Northeast U.S. Sees Second Driest November in More Than a Century

http://www.sciencedaily.com/releases/2012/12/121205142325.htm

ScienceDaily (Dec. 5, 2012) ­ Even though Hurricane Sandy helped create wet start to the month for several states, November 2012 went into the record books as the second-driest November since 1895 in the Northeast. With an average of 1.04 inches or precipitation, the region received only 27 percent of its normal level.

The record driest November was 1917 when the Northeast received only 0.88 inches of precipitation.

All states were drier than average. Departures ranged from 16 percent of normal in Connecticut, their second-driest November, to 37 percent of normal in New Jersey, their 11th driest. Of the remaining states, New Hampshire, Vermont and West Virginia had their second-driest November; Delaware, Maine, Maryland and New York had their third driest. Pennsylvania, Rhode Island and Massachusetts also ranked in the top 10 driest Novembers.

Overall for autumn, the Northeast was slightly drier than average with 11.36 inches of precipitation (98 percent of normal). The region was split down the middle with half of the states drier and half the states wetter than normal. Connecticut took the title of driest state with only 78 percent of normal, while Delaware led the wet states with 120 percent of normal.

The latest U.S. Drought Monitor, issued Nov. 27, indicated abnormal dryness continued in upstate New York while a new area of abnormal dryness popped up near the Vermont-New Hampshire border and in central-southern West Virginia.

In addition to being dry, the Northeast was cooler than normal for November -- in spite of a brief mind-month warmup. With an average temperature of 37.2 degrees, it was 2.5 degrees cooler than normal and was the coolest November since 1997. All states reported below average temperatures for the first time since October 2009. West Virginia and Maine were the coolest at 4.1 degrees below average. Departures for the rest of the states ranged from 4 degrees below normal in New Jersey to 0.9 degrees below normal in Vermont.

Autumn's overall average temperature of 50 degrees was average for November in the Northeast. West Virginia was the coolest at 1.6 degrees below average for the season. Of the warm states, Vermont was the warmest at 1.1 degrees above average.

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The above story is reprinted from materials provided by Cornell University.

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Record High for Global Carbon Emissions

http://www.sciencedaily.com/releases/2012/12/121202164059.htm

ScienceDaily (Dec. 2, 2012) ­ Global carbon dioxide (CO₂) emissions are set to rise again in 2012, reaching a record high of 35.6 billion tonnes -- according to new figures from the Global Carbon Project, co-led by researchers from the Tyndall Centre for Climate Change Research at the University of East Anglia (UEA).

The 2.6 per cent rise projected for 2012 means global emissions from burning fossil fuel are 58 per cent above 1990 levels, the baseline year for the Kyoto Protocol.

This latest analysis by the Global Carbon Project is published December 2 in the journal Nature Climate Change with full data released simultaneously by the journal Earth System Science Data Discussions.

It shows the biggest contributors to global emissions in 2011 were China (28 per cent), the United States (16 per cent), the European Union (11 per cent), and India (7 per cent). (My addition. Not part of this article - Pete Wirth. I thought these pop. figures might be helpful.  China's pop. 1,347,350,000 December 31, 2011, 19.09% of world's pop.,  US. pop. 314,873,000 December 3, 2012,  4.46% of world's pop., India's pop.1,210,193,422 March 1, 2011, 17.15% of world's population.)

Emissions in China and India grew by 9.9 and 7.5 per cent in 2011, while those of the United States and the European Union decreased by 1.8 and 2.8 per cent.

Emissions per person in China of 6.6 tonnes of CO₂ were nearly as high as those of the European Union (7.3), but still below the 17.2 tonnes of carbon used in the United States. Emissions in India were lower at 1.8 tonnes of carbon per person.

Prof Corinne Le Quéré, director of the Tyndall Centre for Climate Change Research and professor at UEA, led the publication of the data. She said: "These latest figures come amidst climate talks in Doha. But with emissions continuing to grow, it's as if no-one is listening to the entire scientific community."

The 2012 rise further opens the gap between real-world emissions and those required to keep global warming below the international target of two degrees.

"I am worried that the risks of dangerous climate change are too high on our current emissions trajectory. We need a radical plan," added Prof Corinne Le Quéré.

The analysis published in Nature Climate Change shows significant emission reductions are needed by 2020 to keep two degrees as a feasible goal.

It shows previous energy transitions in Belgium, Denmark, France, Sweden, and the UK have led to emission reductions as high as 5 per cent each year over decade-long periods, even without climate policy.

Lead author Dr Glen Peters, of the Centre for International Climate and Environmental Research in Norway, said: "Scaling up similar energy transitions across more countries can kick-start global mitigation with low costs. To deepen and sustain these energy transitions in a broad range of countries requires aggressive policy drivers."

Co-author Dr Charlie Wilson, of the Tyndall Centre at UEA, added: "Public policies and institutions have a central role to play in supporting the widespread deployment of low carbon and efficient energy-using technologies, and in supporting innovation efforts."

Emissions from deforestation and other land-use change added 10 per cent to the emissions from burning fossil fuels. The CO₂ concentration in the atmosphere reached 391 parts per million (ppm) at the end of 2011.

These results lends further urgency to recent reports that current emissions pathways are already dangerously high and could lead to serious impacts and high costs on society. These other analyses come from the International Energy Agency, the United Nations Environment Programme, the World Bank, the European Environment Agency, and PricewaterhouseCoopers.

Story Source:

The above story is reprinted from materials provided by University of East Anglia, via AlphaGalileo.

Journal References:

1. Glen P. Peters, Robbie M. Andrew, Tom Boden, Josep G. Canadell, Philippe Ciais, Corinne Le Quéré, Gregg Marland, Michael R. Raupach, Charlie Wilson. The challenge to keep global warming below 2 °C. Nature Climate Change, 2012; DOI: 10.1038/nclimate1783
2. C. Le Quéré, R. J. Andres, T. Boden, T. Conway, R. A. Houghton, J. I. House, G. Marland, G. P. Peters, G. van der Werf, A. Ahlström, R. M. Andrew, L. Bopp, J. G. Canadell, P. Ciais, S. C. Doney, C. Enright, P. Friedlingstein, C. Huntingford, A. K. Jain, C. Jourdain, E. Kato, R. F. Keeling, K. Klein Goldewijk, S. Levis, P. Levy, M. Lomas, B. Poulter, M. R. Raupach, J. Schwinger, S. Sitch, B. D. Stocker, N. Viovy, S. Zaehle, N. Zeng. The global carbon budget 1959–2011. Earth System Science Data Discussions, 2012; 5 (2): 1107 DOI: 10.5194/essdd-5-1107-2012

Sea Levels Rising Faster Than IPCC Projections

The above story is reprinted from materials provided by Institute of Physics.

Journal Reference:

1. Stefan Rahmstorf, Grant Foster, Anny Cazenave. Comparing climate projections to observations up to 2011. Environmental Research Letters, 2012; 7 (4): 044035 DOI: 10.1088/1748-9326/7/4/044035

This is the document referred to in the article Four-Degrees Briefing for the World Bank: The Risks of a Future Without Climate Policy ScienceDaily (Nov. 19, 2012)

The 84-page document,
http://climatechange.worldbank.org/sites/default/files/Turn_Down_the_heat_Why_a_4_degree_centrigrade_warmer_world_must_be_avoided.pdf  

“Turn Down the Heat: Why a 4°C  (7.2 degrees Fahrenheit)  Warmer World Must Be Avoided,” was written for the World Bank by the Potsdam Institute for Climate Impact Research and Climate Analytics and published last week.

" The 4°C scenarios are devastating: the inundation of coastal cities; increasing risks for food production potentially leading to higher malnutrition rates; many dry regions becoming dryer, wet regions wetter; unprecedented heat waves in many regions, especially in the tropics; substantially exacerbated water scarcity in many regions; increased frequency of high-intensity tropical cyclones; and irreversible loss of biodiversity, including coral reef systems," Dr. Jim Yong Kim President, World Bank Group.

© 2012 International Bank for Reconstruction and Development / The World Bank
1818 H Street NW
Washington DC 20433
Telephone: 202-473-1000
Internet: www.worldbank.org

Four-Degrees Briefing for the World Bank: The Risks of a Future Without Climate Policy
http://www.sciencedaily.com/releases/2012/11/121119104842.htm

ScienceDaily (Nov. 19, 2012) — Humankind's emissions of greenhouse gases are breaking new records every year. Hence we're on a path towards 4-degree global warming probably as soon as by the end of this century. This would mean a world of risks beyond the experience of our civilization -- including heat waves, especially in the tropics, a sea-level rise affecting hundreds of millions of people, and regional yield failures impacting global food security. These are some of the results of a report for the World Bank, conducted by the Potsdam Institute for Climate Impact Research (PIK) and Climate Analytics in Berlin. The poorest in the world are those that will be hit hardest, making development without climate policy almost impossible, the researchers conclude.

"The planetary machinery tends to be jumpy, this is to respond disproportionately to disruptions that come with the manmade greenhouse effect," PIK's director Hans Joachim Schellnhuber points out. "If we venture far beyond the 2-degree guardrail, towards 4 degrees, we risk crossing tipping points in the Earth system." This could be the case with coral reefs which face collapse under unabated global warming, or with the Greenland ice sheet. To melt the ice sheet would take thousands of years, yet this might be an irreversible process that could start soon. "The only way to avoid this is to break with the fossil-fuel-age patterns of production and consumption," says Schellnhuber.

Climate impacts: Heat waves, sea-level rise, yield failures

Already today impacts of climate change are observed. The Russian heat wave in 2010, according to preliminary estimates, produced a death toll of several thousand, annual crop failure of about 25%, and economic losses of about US$15 billion. Extreme events like this at 4 degrees global warming would become "the new normal" in some parts of the world, according to the report. In the tropics, the coolest months at the end of the century are likely to be substantially warmer than the warmest months today.

Sea level, under this scenario, would rise by 50 to 100 centimeters within this century, and more so in coming centuries. The rate of rise varies from one region to the other, depending on sea currents and other factors. Projections suggest that sea-level rise will be strongest in countries like the Philippines, Mexico, and India.

Within economic sectors, too, tipping effects with rapidly increasing damages can occur, for instance in agriculture. Already, observations showed that important cereals are sensitive to temperature increases passing certain thresholds, resulting in large-scale yield failure. Changes in the water cycle can aggravate this, when droughts occur or flooding affects farmed land.

World Bank President Kim: "A 4-degree warmer world can, and must be, avoided"

"The report draws from the current state of science and delivers new analysis of heat waves and regional sea-level rise, so of course there remain some uncertainties," says William Hare, co-founder of Climate Analytics in Berlin and guest scientist at PIK. "We work with that by defining risk as potential damage multiplied with the probability -- a rather improbable event can be a great risk if its impacts are huge."

World Bank President Jim Yong Kim who was nominated early this year by US President Barack Obama and assumed his new position in July, has personally been briefed on the 4-degrees report by Schellnhuber some weeks ago in Washington D.C.. "A 4-degree warmer world can, and must be, avoided -- we need to hold warming below 2 degrees," President Kim now said in a statement. "Lack of action on climate change threatens to make the world our children inherit a completely different world than we are living in today. Climate change is one of the biggest single challenges facing development, and we need to assume the moral responsibility to take action on behalf of future generations, especially the poorest."

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The above story is reprinted from materials provided by Potsdam Institute for Climate Impact Research (PIK).

Glaciers Cracking in the Presence of Carbon Dioxide

The above story is reprinted from materials provided by Institute of Physics, via EurekAlert!, a service of AAAS.

Journal Reference:

1. Zhao Qin and Markus J Buehler. Carbon dioxide enhances fragility of ice crystals. J. Phys. D: Appl. Phys., 2012 DOI: 10.1088/0022-3727/45/44/445302

Glacial Thinning Has Sharply Accelerated at Major South American Icefields

The above story is reprinted from materials provided by American Geophysical Union.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

1. Michael J. Willis, Andrew K. Melkonian, Matthew E. Pritchard, and Andrés Rivera. Ice loss from the Southern Patagonian Ice Field, South America, between 2000 and 2012. Geophysical Research Letters, 2012; DOI: 10.1029/2012GL053136, 2012

Arctic Sea Ice Reaches Lowest Extent Ever Recorded

The above story is reprinted from materials provided by University of Colorado at Boulder.

Climate Change Will Have Profound Effects On Northeast U.S. Forests, Report Says

The above story is reprinted from materials provided by USDA Forest Service - Northern Research Station.

Extreme Weather Linked to Global Warming, Nobel Prize-Winning Scientist Says
http://www.sciencedaily.com/releases/2012/08/120820114041.htm

ScienceDaily (Aug. 20, 2012) — New scientific analysis strengthens the view that record-breaking summer heat, crop-withering drought and other extreme weather events in recent years do, indeed, result from human activity and global warming, Nobel Laureate Mario J. Molina, Ph.D., said at a conference in Philadelphia on August 20.

Molina, who shared the 1995 Nobel Prize in Chemistry for helping save the world from the consequences of ozone depletion, presented the keynote address at the 244th National Meeting & Exposition of the American Chemical Society.

"People may not be aware that important changes have occurred in the scientific understanding of the extreme weather events that are in the headlines," Molina said. "They are now more clearly connected to human activities, such as the release of carbon dioxide ? the main greenhouse gas ? from burning coal and other fossil fuels."

Molina emphasized that there is no "absolute certainty" that global warming is causing extreme weather events. But he said that scientific insights during the last year or so strengthen the link. Even if the scientific evidence continues to fall short of the absolute certainly measure, the heat, drought, severe storms and other weather extremes may prove beneficial in making the public more aware of global warming and the need for action, said Molina.

"It's important that people are doing more than just hearing about global warming," he said. "People may be feeling it, experiencing the impact on food prices, getting a glimpse of what everyday life may be like in the future, unless we as a society take action."

Molina, who is with the University of California, San Diego, suggested a course of action based on an international agreement like the Montreal Protocol that phased out substances responsible for the depletion of the ozone layer.

"The new agreement should put a price on the emission of greenhouse gases, which would make it more economically favorable for countries to do the right thing. The cost to society of abiding by it would be less than the cost of the climate change damage if society does nothing," he said.

In the 1970s and 1980s, Molina, F. Sherwood Rowland, Ph.D., and Paul J. Crutzen, Ph.D., established that substances called CFCs in aerosol spray cans and other products could destroy the ozone layer. The ozone layer is crucial to life on Earth, forming a protective shield high in the atmosphere that blocks potentially harmful ultraviolet rays in sunlight. Molina, Rowland and Crutzen shared the Nobel Prize for that research. After a "hole" in that layer over Antarctica was discovered in 1985, scientists established that it was indeed caused by CFCs, and worked together with policymakers and industry representatives around the world to solve the problem. The result was the Montreal Protocol, which phased out the use of CFCs in 1996.

Adopted and implemented by countries around the world, the Montreal Protocol eliminated the major cause of ozone depletion, said Molina, and stands as one of the most successful international agreements. Similar agreements, such as the Kyoto Protocol, have been proposed to address climate change. But Molina said these agreements have largely failed.

Unlike the ozone depletion problem, climate change has become highly politicized and polarizing, he pointed out. Only a small set of substances were involved in ozone depletion, and it was relatively easy to get the small number of stakeholders on the same page. But the climate change topic has exploded. "Climate change is a much more pervasive issue," he explained. "Fossil fuels, which are at the center of the problem, are so important for the economy, and it affects so many other activities. That makes climate change much more difficult to deal with than the ozone issue."

In addition to a new international agreement, other things must happen, he said. Scientists need to better communicate the scientific facts underlying climate change. Scientists and engineers also must develop cheap alternative energy sources to reduce dependence on fossil fuels.

Molina said that it's not certain what will happen to Earth if nothing is done to slow down or halt climate change. "But there is no doubt that the risk is very large, and we could have some consequences that are very damaging, certainly for portions of society," he said. "It's not very likely, but there is some possibility that we would have catastrophes."
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The above story is reprinted from materials provided by American Chemical Society (ACS).

July 2012 Marked Hottest Month On Record for Contiguous U.S.; Drought Expands to Cover Nearly 63 Percent of the Lower 48

• Higher-than-average temperatures engulfed much of the contiguous U.S. during July, with the largest temperature departures from the 20th century average occurring across most of the Plains, the Midwest, and along the Eastern Seaboard. Virginia had its warmest July on record, with a statewide temperature 4.0°F above average. In total, 32 states had July temperatures among its ten warmest, with seven states having their second warmest July on record.
• Drier-than-average conditions continued across the Central Plains and Midwest during July. Nebraska, Iowa, Illinois, and Missouri had July precipitation totals ranking among their ten driest. Maine had its fifth driest July on record.
• An active storm pattern in the Southwest contributed to California having its fifth wettest July on record and Nevada having its eighth wettest. Wetter-than-average conditions were also observed through the rest of the Southwest, along the western Gulf Coast, and through the Ohio Valley where West Virginia had its tenth wettest July.
• The warm and dry conditions over a large portion of the country were associated with ideal wildfire conditions. Over 2 million acres were burned nationwide during July due to wildfires, nearly half a million acres above average, and the fourth most on record since 2000.

• The May-July months, an important period for agriculture, was the second warmest and 12th driest such three-months for the Lower 48, contributing to rapid expansion of drought. The central regions of the country were hardest hit by the drought, where ten states had three-month precipitation totals among their ten driest, including Nebraska, Kansas, and Arkansas which were record dry.
• According to the July 31, 2012, U.S. Drought Monitor (USDM), 62.9 percent of the contiguous U.S. was experiencing moderate to exceptional drought at the end of July. This is an increase of about 6.9 percent compared to the end of June. The maximum value of 63.9 percent reached on July 24 is a record in the 13-year history of the USDM.
• The area of the country in the worst drought categories (extreme to exceptional drought) doubled from 10 percent last month to 22 percent this month. The extreme dryness and excessive heat devastated crops and livestock from the Great Plains to Midwest.
• The Primary Corn and Soybean Agricultural Belt, hard hit by drought, experienced its eighth driest July, third driest June-July, and sixth driest April-July (growing season) in the 1895-2012 record.
• According to the Palmer Drought Severity Index, whose record spans the 20th century, about 57 percent of the contiguous U.S. was experiencing moderate-to-extreme drought in July. The last drought this extensive was in December 1956 when about 58 percent of the nation was in moderate-to-extreme drought.

• The January-July period was the warmest first seven months of any year on record for the contiguous United States. The national temperature of 56.4°F was 4.3°F above the long-term average. Most of the contiguous U.S. was record and near-record warm for the seven-month period, except the Pacific Northwest, which was near average.
• The first seven months of 2012 were drier than average, ranking as 15th driest January-July on record. Below-average precipitation totals were observed for a large portion of the country, with 12 states having January-July precipitation totals among their ten driest. Above-average precipitation was observed for the Upper Midwest and the Pacific Northwest.
• The U.S. Climate Extremes Index (USCEI), an index that tracks the highest and lowest 10 percent of extremes in temperature, precipitation, drought and tropical cyclones across the contiguous U.S., was a record-large 46 percent during the January-July period, over twice the average value, and surpassing the previous record large CEI of 42 percent which occurred in 1934. Extremes in warm daytime temperatures (83 percent) and warm nighttime temperatures (74 percent) both covered record large areas of the nation, contributing to the record high year-to-date USCEI value.

• The August 2011-July 2012 period was the warmest 12-month period of any 12-months on record for the contiguous U.S., narrowly surpassing the record broken last month for the July 2011-June 2012 period by 0.07°F. The nationally averaged temperature of 56.1°F was 3.3°F above the long term average. Except Washington, which was near average, every state across the contiguous U.S. had warmer than average temperatures for the period.

• NOAA July U.S. Climate Report: http://www.ncdc.noaa.gov/sotc/national/2012/7
• NOAA Climate Portal: http://www.climate.gov/
• U.S. Drought Monitor: http://www.drought.gov/

The above story is reprinted from materials provided by National Oceanic and Atmospheric Administration.

Chronic 2000-04 Drought, Worst in 800 Years, May Be the 'New Normal'

The above story is reprinted from materials provided by Oregon State University, via Newswise.

Journal Reference:

1. Christopher R. Schwalm, Christopher A. Williams, Kevin Schaefer, Dennis Baldocchi, T. Andrew Black, Allen H. Goldstein, Beverly E. Law, Walter C. Oechel, Kyaw Tha Paw U, Russel L. Scott. Reduction in carbon uptake during turn of the century drought in western North America. Nature Geoscience, 2012; DOI: 10.1038/NGEO1529

Climate Change Linked to Ozone Loss: May Result in More Skin Cancer

The above story is reprinted from materials provided by Harvard University, via EurekAlert!, a service of AAAS.

1. James G. Anderson, David M. Wilmouth, Jessica B. Smith, and David S. Sayres. UV Dosage Levels in Summer: Increased Risk of Ozone Loss from Convectively Injected Water Vapor. Science, 26 July 2012 DOI: 10.1126/science.1222978

Global CO2

The above story is reprinted from materials provided by European Commission, Joint Research Centre (JRC)

Glacier Break Creates Ice Island Twice Size of Manhattan

The above story is reprinted from materials provided by University of Delaware. The original article was written by Tracey Bryant.

Extreme Heat Raises Climate Change Questions, Concerns

The above story is reprinted from materials provided by University of Wisconsin-Madison. The original article was written by Steve Pomplun.

Arctic Warming Linked to Combination of Reduced Sea Ice and Global Atmospheric Warming
http://www.sciencedaily.com/releases/2012/07/120706164203.htm
ScienceDaily (July 6, 2012) ­ The combination of melting sea ice and global atmospheric warming are contributing to the high rate of warming in the Arctic, where temperatures are increasing up to four times faster than the global average, a new University of Melbourne study has shown.

Professor Ian Simmonds from the University of Melbourne's School of Earth Sciences co-authored the study and said the new information showed this combined effect at both ground and atmospheric level played a key role in increasing the rate of warming in the Arctic.

"Loss of sea ice contributes to ground level warming while global warming intensifies atmospheric circulation and contributes to increased temperatures higher in the Arctic atmosphere," Professor Simmonds said.

Lead author, Dr James Screen of the School of Earth Sciences at the University of Melbourne, said the sea ice acted like a shiny lid on the Arctic Ocean.

"When it is heated, it reflects most of the incoming sunlight back into space. When the sea ice melts, more heat is absorbed by the water. The warmer water then heats the atmosphere above it," he said.

Professor Simmonds said as temperatures increase across the globe, so does the intensity of atmospheric circulation.

"This circulation transports energy to the Arctic region, increasing temperatures further up in the atmosphere," he said.

"Water vapour is a very strong greenhouse gas. As the atmosphere warms it can hold more moisture, which acts as a positive feedback signal, increasing the greenhouse effect. However, in the cold Arctic where there is less moisture in the air, this positive feedback is much weaker hence the 'direct' greenhouse effect is smaller in the Arctic than elsewhere.

"Even though the Arctic region has a relatively small greenhouse effect, the effect of the melted ice combined with greater transports of heat from the south are more than enough to make up for this modest 'local' greenhouse warming."

The study was published in Geophysical Research Letters and featured in Nature.
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The above story is reprinted from materials provided by University of Melbourne.

Heating Up

Greater Los Angeles to Heat Up an Average 4 to 5 Degrees by Mid-Century
http://www.sciencedaily.com/releases/2012/06/120621195908.htm

ScienceDaily (June 21, 2012) ­ A ground breaking new study led by UCLA climate expert Alex Hall shows that climate change will cause temperatures in the Los Angeles region to rise by an average of 4 to 5 degrees Fahrenheit by the middle of this century, tripling the number of extremely hot days in the downtown area and quadrupling the number in the valleys and at high elevations.

Released June 22, "Mid-Century Warming in the Los Angeles Region" is the first study to provide specific climate-change predictions for the greater Los Angeles area, with unique predictions down to the neighborhood level. The report, the most sophisticated regional climate study ever developed, was produced by UCLA with funding and support from the city of Los Angeles, in partnership with the Los Angeles Regional Collaborative for Climate Action and Sustainability (LARC).

"The changes our region will face are significant, and we will have to adapt," said Hall, an associate professor in UCLA's Department of Atmospheric and Oceanic Sciences who is also a lead author on the Intergovernmental Panel on Climate Change reports, which, among other things, assess global climate-change simulations for the United Nations.

"Every season of the year in every part of the county will be warmer," Hall said. "This study lays a foundation for the region to confront climate change. Now that we have real numbers, we can talk about adaptation."

The LARC's unprecedented coalition of cities, universities, businesses, non-profits and other agencies made the study possible. Mayor Antonio Villaraigosa and the city of Los Angeles led the way, obtaining a $613,774 grant from the U.S. Department of Energy to study and share climate research and committing $484,166 to commission UCLA's climate-change study. Though scientists knew to expect warming, this is the first time policymakers in the Los Angeles area have precise information on which to base their plans.

"UCLA's model shows projected climate changes down to the neighborhood level, allowing us to apply the rigor of science to long-term planning for our city and our entire region," Villaraigosa said. "With good data driving good policies, we can craft innovative solutions that will preserve our environment and enhance the quality of life for the next generation of Angelenos."

Facts and figures from the study

The study looked at the years 2041-60 to predict the average temperature change by mid-century. The data covers all of Los Angeles County and 30 to 60 miles beyond, including all of Orange County and parts of Ventura, San Bernardino and Riverside counties, and reaching as far as Palm Springs, Bakersfield and Santa Barbara. The study overlaid this entire area with a grid of squares 1.2 miles across and provided unique temperature predictions for each square. This is in contrast to global climate models, which normally use grids 60 to 120 miles across -- big enough to include areas as different as Long Beach and Lancaster.

According to the study, coastal areas like Santa Monica and Long Beach are likely to warm an average of 3 to 4 degrees. Dense urban areas like downtown Los Angeles and the San Fernando and San Gabriel valleys will warm an average of 4 degrees, and mountain and desert regions like Palm Springs and Lancaster will warm 4 to 5 degrees.

Some of the smallest changes predicted, yet still nearing a 4-degree increase, are in Oxnard (3.68 degrees), Venice (3.70), Santa Barbara (3.73), Santa Monica (3.74), San Pedro (3.78), Torrance (3.80), Long Beach (3.82) and Santa Ana (3.85). Among the highest predicted increases are Wrightwood (5.37), Big Bear Lake (5.23), Palm Springs (5.15), Palmdale (4.92), Lancaster (4.87), Bakersfield (4.48) and Santa Clarita (4.44). Table 2 in the study calls out 27 distinct locations, such as downtown Los Angeles (3.92), San Fernando (4.19), Woodland Hills (4.26), Eagle Rock (3.98), Pasadena (4.05), Pomona (4.09), Glendale (3.99) and Riverside (4.23).

These figures are only annual averages, and the day-to-day increase in temperatures will vary, said Hall, who is a member of UCLA's Institute of the Environment and Sustainability (IoES) and director of the institute's Center for Climate Change Solutions. Southern Californians should expect slightly warmer winters and springs but much warmer summers and falls, with more frequent heat waves. Temperatures now seen only on the seven hottest days of the year in each region will occur two to six times as often. The number of days when the temperature will climb above 95 degrees will increase two to four times, depending on the location. Those days will roughly double on the coast, triple in downtown Los Angeles and Pasadena, and quadruple in Woodland Hills. In Palm Springs, the number of extremely hot days will increase from an annual average of 75 to roughly 120.

"Places like Lancaster and Palm Springs are already pretty hot areas, and when you tack on warming of 5 to 6 degrees, that's a pretty noticeable difference," Hall said. "If humans are noticing it, so are plants, animals and ecosystems. These places will be qualitatively different than they are now."

The most sophisticated regional climate study ever developed

The type of climate modeling used in the study is done almost exclusively at the national or international level, said Paul Bunje, the managing director of the LARC, which is based at UCLA's Institute of the Environment and Sustainability. Other cities and states have localized global climate models -- but usually by localizing only one model. Hall's team needed months of computer time to downscale 22 global climate models, each with slightly different assumptions about how to predict climate change or factors like future greenhouse gas emissions.

Hall's team included UCLA postdoctoral students Fengpeng Sun and Daniel Walton and graduate student Mark Nakamura. Once they recalculated the almost two dozen global models at the local level, the team analyzed the results and integrated them into an ensemble projection to create the forecast for the entire region.

"This is the best, most sophisticated climate science ever done for a city," said Bunje, who is also the executive director of UCLA's IoES Center for Climate Change Solutions.

"L.A. is one of the first cities to get its act together, from the scientists all the way up to the mayor," Bunje said. "Nobody knew precisely how to adapt to climate change because no one had the data -- until now. These are shocking numbers, and we will have to adapt."

Cutting emissions will reduce but not eliminate warming

Cutting greenhouse gas emissions could reduce the impact on Los Angeles, Hall said. However, even if the world has unanticipated -- and perhaps unrealistic -- success in drastically reducing greenhouse gas emissions, the greater Los Angeles area will still warm to about 70 percent of the currently predicted levels, the study found.

"We looked not only at a business-as-usual scenario where greenhouse gas emissions continue but also at a scenario where emissions are curtailed," Hall said. "Even if we drastically cut pollution worldwide, there will still be quite a bit of warming in Los Angeles. I was a little taken aback by how much warming remains, no matter how aggressively we cut back. It was sobering."

"Mid-Century Warming in the Los Angeles Region" is the first of five planned studies Hall will conduct for the city and the LARC about how climate change will affect the Southland. Hall's team plans to develop similarly comprehensive models for local rainfall, Santa Ana wind patterns, coastal fog (including June gloom), and soil moisture, run-off and evaporation. Preliminary results already show that Santa Ana winds and June gloom will react to climate change, Hall said.

Global warming is local warming

"I think for many people, climate change still feels like a nebulous, abstract, potential future change, and this makes it more real," Hall said. "It's eye-opening to see how much it will warm where you live. This data lays a foundation for really confronting this issue, and I'm very optimistic that we can confront and adapt to a changing climate."

Report: http://c-change.la/pdf/LARC-web.pdf
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The above story is reprinted from materials provided by University of California - Los Angeles. The original article was written by Alison Hewitt.

Drought Monitor Shows Record-Breaking Expanse of Drought Across United States

The above story is reprinted from materials provided by University of Nebraska-Lincoln.

U.S. Experienced Second Warmest May, Warmest Spring On Record, NOAA Reports

• Warmer-than-average temperatures occurred across the contiguous U.S. except the Northwest in May. Twenty-six states had May temperatures ranking among their ten warmest.
• Precipitation patterns across the contiguous U.S. were mixed during May. The Eastern Seaboard and Upper Midwest were wetter than average. North Carolina, South Carolina, Vermont, New Hampshire and Minnesota had May precipitation totals among their ten wettest. Dry conditions prevailed across the Mid-Mississippi River Valley, Southern Plains and the Interior West with Arkansas, Missouri, Kansas, Nevada and Utah having a top ten dry May.
• Tropical Storm Beryl made landfall near Jacksonville, Fla., on May 28, bringing beneficial rainfall to parts of the drought-stricken Southeast. Beryl occurred on the heels of Tropical Storm Alberto, which occurred offshore the Carolinas, marking the third time on record that two tropical cyclones reached tropical storm strength during May (prior to the start of June 1 hurricane season) in the North Atlantic basin.
• Ongoing drought, combined with windy conditions, created ideal wildfire conditions across the Southwest. The Whitewater-Baldy Fire complex in the Gila National Forest of western New Mexico charred over 210,000 acres by the beginning of June. It surpassed 2011's Las Conchas Fire as largest wildfire on record for the state.
• According to the U.S. Drought Monitor, as of May 29, 37.4 percent of the contiguous U.S. experienced drought conditions, a slight decrease from 38.2 percent at the beginning of May. Drought conditions improved across the coastal Southeast, the Southern Plains, Northeast and Upper Midwest while they deteriorated for parts of the Mid-South and Southwest.

• The nationally averaged temperature of 57.1°F during spring was 5.2°F above the long-term average. With warmest March, third warmest April and second warmest May, spring 2012 marked the largest temperature departure from average of any season on record for the contiguous United States.
• Spring was drier-than-average for the contiguous U.S. as a whole, with a national precipitation total of 7.47 inches, 0.24 inch below average.
• Record and near-record warmth dominated the eastern two-thirds of the nation during spring. Thirty-one states were record warm for the season and 11 additional states had spring temperatures ranking among their ten warmest. Only Oregon and Washington had spring temperatures near normal.
• Wetter-than-average conditions prevailed from the West Coast through the Northern Plains and into the Upper Midwest. Oregon was record wet and Minnesota and Washington were third wettest. The Intermountain West, Ohio Valley, and parts of the Mid-Atlantic were drier than average. Colorado, Utah, Wyoming, Indiana, and Delaware had a top ten dry spring.
• The U.S. Climate Extremes Index (USCEI), an index that tracks the highest and lowest 10 percent of extremes in temperature, precipitation, drought and tropical cyclones across the contiguous U.S., was a record-large 44 percent during the March-May period, over twice the average value. Extremes in warm daytime temperatures (81 percent) and warm nighttime temperatures (72 percent) covered large areas of the nation, contributing to the record high value.

• The January-May months totaled the warmest such period on record for the contiguous United States, with an average temperature of 49.2°F, 5.0°F above the long-term average. Twenty-nine states, all east of the Rockies, were record warm for the five-month period and an additional 14 states had temperatures for the period among their ten warmest.
• The year's first five months also brought dry conditions to much of the East. The Southwest was drier than average while wetter-than-average conditions persisted for the Pacific Northwest, Upper Midwest and the western Gulf Coast. The national precipitation total for the five-month period was nearly 1.0 inch below average.

• The June 2011-May 2012 period was the warmest 12-month period of any 12 months on record for the contiguous United States. The nationally averaged temperature of 56.0°F was 3.2°F above the long-term average, surpassing the previous warmest 12-month period set last month by 0.4°F. The 12-month period encapsulated the second warmest summer, fourth warmest winter, and the warmest spring on record. Every state across the contiguous U.S. had warmer than average temperatures for the period, except Washington, which was near normal.

• May U.S. Climate Report: http://www.ncdc.noaa.gov/sotc/national/2012/5
• NOAA Climate Portal: http://www.climate.gov/

The above story is reprinted from materials provided by National Oceanic and Atmospheric Administration.

Arctic Ice Melt Is Setting Stage for Severe Winters

The above story is reprinted from materials provided by Cornell University. The original article was written by Anne Ju.

Adirondack Lakes in North Eastern US Lose Ice Cover as Climate Warms: Most Pristine Lake Marks Biggest Change

The above story is reprinted from materials provided by SUNY College of Environmental Science and Forestry, via Newswise.

1. Colin M. Beier, John C. Stella, Martin Dov iak, Stacy A. McNulty. Local climatic drivers of changes in phenology at a boreal-temperate ecotone in eastern North America. Climatic Change, 2012; DOI: 10.1007/s10584-012-0455-z

U. S. Temperatures Hit Record Highs in March

The above story is reprinted from materials provided by University of Alabama Huntsville, via Newswise.

New Report On the State of Polar Regions

http://www.sciencedaily.com/releases/2012/04/120403193733.htm

ScienceDaily (Apr. 3, 2012) ­ The U.S. National Research Council has just released a synthesis of reports from thousands of scientists in 60 countries who took part in the International Polar Year (IPY) 2007-08, the first in over 50 years to offer a benchmark for environmental conditions and new discoveries in the polar regions.

University of Massachusetts Amherst geosciences researcher and expert in the paleoclimate of the Arctic, Julie Brigham-Grette, co-chaired the NRC report, "Lessons and Legacies of the IPY 2007-08" with leading Antarctic climate scientist Robert Bindschadler of NASA.

Among the major findings is that global warming is changing the face of Antarctica and the Arctic faster than expected. For example, in 2007 scientists documented a 27 percent loss of sea ice in a single year, Brigham-Grette says. Also, ice sheets around the poles are now showing evidence of serious retreat, expected to continue and perhaps accelerate over coming centuries as warm ocean currents melt the ice front faster than anyone had grasped before. Sea level rise from melting polar ice sheets is today slowly affecting every shoreline on the planet.

"As a result of this work, we have a new benchmark. Seven of 12 Antarctic Peninsula ice shelves are either gone or now in severe decline," she adds. "This type of information makes the report all the more important because the changes we expect to see in the next few decades are going to be incredible."

As co-authors, she and Bindschadler testified last week before representatives of the National Science Foundation, its Office of Polar Programs, NASA, NOAA, the U.S. Geological Survey, Office of Naval Research, the State Department and the U.S. Arctic Research Commission. Additional briefings could be scheduled if there are questions or responses to the NRC from Congress, Brigham-Grette says.

Worldwide, scores of oceanographers, meteorologists, geologists, climate scientists, ecologists and other researchers contributed to the report. For example, biologists document diatoms, microscopic phytoplankton at the base of the food chain, in North Atlantic waters where they hadn't been in 800,000 years, the last time the Arctic provided a cold barrier to migration, Brigham-Grette says. Fish specialists see commercial and other species migrating ever northward to suitable habitats. "The fishermen are following," she says. "It's a whole new ballgame for the U.S. Coast Guard and those trying to regulate harvests."

The UMass Amherst geoscientist's own research using ancient sediment cores from Northeast Russia's Lake El'gygytgyn offers a new look at how Antarctic and Arctic warming over the last few million years occurred in sync when forced by the Earth system and feedbacks. "We're beginning to see that when the west Antarctic ice sheet collapses, the Arctic warms up. This is a new benchmark linking warming events in these two places for the first time."

In the Antarctic, new imaging techniques deployed during the recent IPY allowed scientists for the first time to visualize a new range, the Gamburtsev Mountains, with peaks as big as the Alps under the east Antarctic ice sheet. They may have been the ice sheet's nucleus millions of years ago. Others found hundreds of freshwater lakes under Antarctic ice, with more being discovered every day.

Brigham-Grette says, "I think if you look at everything we've learned, we see the polar regions are much more vulnerable to global warming than we thought. Global biological and oceanographic systems are responding faster than we ever expected. Earth has gone through this before, and some past warm cycles have been extreme, but we as humans have never seen anything like it in our 10,000 years on the planet. It's extraordinary."

As they release the NRC report to policymakers this week, Brigham-Grette says the authors understand that leaders must try to balance the country's energy needs at the same time they address global climate change by decreasing fossil fuel use.

Two social advances to emerge from the recent IPY are a remarkable increase in the number of women and minorities in leadership roles in science compared to 50 years ago along with the "massive" educational effort and increased interest in and public awareness of issues facing polar regions, she adds.

Among scientists, the IPY led to many new international and multi-disciplinary collaborations that promise to continue, says Brigham-Grette, plus a new international network of young polar scientists. "With the expense of travel and research today, no one country can do it alone, so there's more sharing of resources and data. It's a very much richer environment for study today."

The above story is reprinted from materials provided by University of Massachusetts Amherst, via Newswise.

Amount of Coldest Antarctic Water Near Ocean Floor Decreasing for Decades
http://www.sciencedaily.com/releases/2012/04/120403153850.htm

ScienceDaily (Apr. 3, 2012) — Scientists have found a large reduction in the amount of the coldest deep ocean water, called Antarctic Bottom Water, all around the Southern Ocean using data collected from 1980 to 2011. These findings, in a study now online, will likely stimulate new research on the causes of this change.

Two oceanographers from NOAA and the University of Washington find that Antarctic Bottom Water has been disappearing at an average rate of about eight million metric tons per second over the past few decades, equivalent to about fifty times the average flow of the Mississippi River or about a quarter of the flow of the Gulf Stream in the Florida Straits.

"Because of its high density, Antarctic Bottom Water fills most of the deep ocean basins around the world, but we found that the amount of this water has been decreasing at a surprisingly fast rate over the last few decades," said lead author Sarah Purkey, graduate student at the School of Oceanography at the University of Washington in Seattle, Wash. "In every oceanographic survey repeated around the Southern Ocean since about the 1980s, Antarctic Bottom Water has been shrinking at a similar mean rate, giving us confidence that this surprisingly large contraction is robust."

Antarctic Bottom Water is formed in a few distinct locations around Antarctica, where seawater is cooled by the overlying air and made saltier by ice formation. The dense water then sinks to the sea floor and spreads northward, filling most of the deep ocean around the world as it slowly mixes with warmer waters above it.

The world's deep ocean currents play a critical role in transporting heat and carbon around the planet, thus regulating our climate.

While previous studies have shown that the bottom water has been warming and freshening over the past few decades, these new results suggest that significantly less of this bottom water has been formed during that time than in previous decades.

"We are not sure if the rate of bottom water reduction we have found is part of a long-term trend or a cycle," said co-author Gregory C. Johnson, Ph.D., an oceanographer at NOAA's Pacific Marine Environmental Laboratory in Seattle. "We need to continue to measure the full depth of the oceans, including these deep ocean waters, to assess the role and significance that these reported changes and others like them play in the Earth's climate."

Changes in the temperature, salinity, dissolved oxygen, and dissolved carbon dioxide of this prominent water mass have important ramifications for Earth's climate, including contributions to sea level rise and the rate of Earth's heat uptake.

"People often focus on fluctuations of currents in the North Atlantic Ocean as an indicator of climate change, but the Southern Ocean has undergone some very large changes over the past few decades and also plays a large role in shaping our climate," said Johnson.

The data used in this study are highly accurate temperature data repeated at roughly 10-year intervals by an international program of repeated ship-based oceanographic surveys. Within the U.S., the collection of these data has been a collaborative effort of governmental laboratory and university scientists, funded primarily by NOAA and the National Science Foundation. However, much of the data used in this study were measured by international colleagues.
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The above story is reprinted from materials provided by National Oceanic and Atmospheric Administration.
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Journal Reference:

1.Sarah G. Purkey, Gregory C. Johnson. Global contraction of Antarctic Bottom Water between the 1980s and 2000s*. Journal of Climate, 2012; : 120315135854004 DOI: 10.1175/JCLI-D-11-00612.1
Ocean Acidification Rate May Be Unprecedented, Study Says

ScienceDaily (Mar. 1, 2012) ­ The world's oceans may be turning acidic faster today from human carbon emissions than they did during four major extinctions in the last 300 million years, when natural pulses of carbon sent global temperatures soaring, says a new study in Science. The study is the first of its kind to survey the geologic record for evidence of ocean acidification over this vast time period.
"What we're doing today really stands out," said lead author Bärbel Hönisch, a paleoceanographer at Columbia University's Lamont-Doherty Earth Observatory. "We know that life during past ocean acidification events was not wiped out -- new species evolved to replace those that died off. But if industrial carbon emissions continue at the current pace, we may lose organisms we care about -- coral reefs, oysters, salmon."
The oceans act like a sponge to draw down excess carbon dioxide from the air; the gas reacts with seawater to form carbonic acid, which over time is neutralized by fossil carbonate shells on the seafloor. But if CO₂ goes into the oceans too quickly, it can deplete the carbonate ions that corals, mollusks and some plankton need for reef and shell-building.
That is what is happening now. In a review of hundreds of paleoceanographic studies, a team of researchers from five countries found evidence for only one period in the last 300 million years when the oceans changed even remotely as fast as today: the Paleocene-Eocene Thermal Maximum, or PETM, some 56 million years ago. In the early 1990s, scientists extracting sediments from the seafloor off Antarctica found a layer of mud from this period wedged between thick deposits of white plankton fossils. In a span of about 5,000 years, they estimated, a mysterious surge of carbon doubled atmospheric concentrations, pushed average global temperatures up by about6 degrees C, and dramatically changed the ecological landscape.
The result: carbonate plankton shells littering the seafloor dissolved, leaving the brown layer of mud. As many as half of all species of benthic foraminifers, a group of single-celled organisms that live at the ocean bottom, went extinct, suggesting that organisms higher in the food chain may have also disappeared, said study co-author Ellen Thomas, a paleoceanographer at Yale University who was on that pivotal Antarctic cruise. "It's really unusual that you lose more than 5 to 10 percent of species over less than 20,000 years," she said. "It's usually on the order of a few percent over a million years." During this time, scientists estimate, ocean pH -- a measure of acidity--may have fallen as much as 0.45 units. (As pH falls, acidity rises.)
In the last hundred years, atmospheric CO₂ has risen about 30 percent, to 393 parts per million, and ocean pH has fallen by 0.1 unit, to 8.1--an acidification rate at least 10 times faster than 56 million years ago, says Hönisch. The Intergovernmental Panel on Climate Change predicts that pH may fall another 0.3 units by the end of the century,to 7.8, raising the possibility that we may soon see ocean changes similar to those observed during the PETM.
More catastrophic events have shaken earth before, but perhaps not as quickly. The study finds two other times of potential ocean acidification: the extinctions triggered by massive volcanism at the end of the Permian and Triassic eras, about 252 million and 201 million years ago respectively. But the authors caution that the timing and chemical changes of these events is less certain. Because most ocean sediments older than 180 million years have been recycled back into the deep earth, scientists have fewer records to work with.
During the end of the Permian, about 252 million years ago, massive volcanic eruptions in present-day Russia led to a rise in atmospheric carbon, and the extinction of 96 percent of marine life. Scientists have found evidence for ocean dead zones and the survival of organisms able to withstand carbonate-poor seawater and high blood-carbon levels, but so far they have been unable to reconstruct changes in ocean pH or carbonate.
At the end of the Triassic, about 201 million years ago, a second burst of mass volcanism doubled atmospheric carbon. Coral reefs collapsed and many sea creatures vanished. Noting that tropical species fared the worst, some scientists question if global warming rather than ocean acidification was the main killer at this time.
The effects of ocean acidification today are overshadowed for now by other problems, ranging from sewage pollution and hotter summer temperatures that threaten corals with disease and bleaching. However, scientists trying to isolate the effects of acidic water in the lab have shown that lower pH levels can harm a range of marine life, from reef and shell-building organisms to the tiny snails favored by salmon. In a recent study, scientists from Stony Brook University found that the larvae of bay scallops and hard clams grow best at pre-industrial pH levels, while their shells corrode at the levels projected for 2100. Off the U.S. Pacific Northwest, the death of oyster larvae has recently been linked to the upwelling of acidic water there.
In parts of the ocean acidified by underwater volcanoes venting carbon dioxide, scientists have seen alarming signs of what the oceans could be like by 2100. In a 2011 study of coral reefs off Papua New Guinea, scientists writing in the journal Nature Climate Change found that when pH dropped to 7.8, reef diversity declined by as much as 40 percent. Other studies have found that clownfish larvae raised in the lab lose their ability to sniff out predators and find their way home when pH drops below 7.8.
"It's not a problem that can be quickly reversed," said Christopher Langdon, a biological oceanographer at the University of Miami who co-authored the study on Papua New Guinea reefs. "Once a species goes extinct it's gone forever. We're playing a very dangerous game."
It may take decades before ocean acidification's effect on marine life shows itself. Until then, the past is a good way to foresee the future, says Richard Feely, an oceanographer at the National Oceanic and Atmospheric Administration who was not involved in the study. "These studies give you a sense of the timing involved in past ocean acidification events -- they did not happen quickly," he said. "The decisions we make over the next few decades could have significant implications on a geologic timescale."

The study was funded by the U.S. National Science Foundation.

The above story is reprinted from materials provided by The Earth Institute at Columbia University.

1. Bärbel Hönisch, Andy Ridgwell, Daniela N. Schmidt, Ellen Thomas, Samantha J. Gibbs, Appy Sluijs, Richard Zeebe, Lee Kump, Rowan C. Martindale, Sarah E. Greene, Wolfgang Kiessling, Justin Ries, James C. Zachos, Dana L. Royer, Stephen Barker, Thomas M. Marchitto Jr., Ryan Moyer, Carles Pelejero, Patrizia Ziveri, Gavin L. Foster, and Branwen Williams. The Geological Record of Ocean Acidification. Science, March 2, 2012 DOI: 10.1126/science.1208277

• NASA Finds 2011 Ninth-Warmest Year On Record
  http://www.sciencedaily.com/releases/2012/01/120119152353.htm
  
  ScienceDaily (Jan. 19, 2012) ­ The global average surface temperature in 2011 was the ninth warmest since 1880, according to NASA scientists. The finding continues a trend in which nine of the 10 warmest years in the modern meteorological record have occurred since the year 2000. NASA's Goddard Institute for Space Studies (GISS) in New York, which monitors global surface temperatures on an ongoing basis, released an updated analysis that shows temperatures around the globe in 2011 compared to the average global temperature from the mid-20th century. The comparison shows how Earth continues to experience warmer temperatures than several decades ago. The average temperature around the globe in 2011 was 0.92 degrees F (0.51 C) warmer than the mid-20th century baseline.  "We know the planet is absorbing more energy than it is emitting," said GISS Director James E. Hansen. "So we are continuing to see a trend toward higher temperatures. Even with the cooling effects of a strong La Niña influence and low solar activity for the past several years, 2011 was one of the 10 warmest years on record."  The difference between 2011 and the warmest year in the GISS record (2010) is 0.22 degrees F (0.12 C). This underscores the emphasis scientists put on the long-term trend of global temperature rise. Because of the large natural variability of climate, scientists do not expect temperatures to rise consistently year after year. However, they do expect a continuing temperature rise over decades. The first 11 years of the 21st century experienced notably higher temperatures compared to the middle and late 20th century, Hansen said. The only year from the 20th century in the top 10 warmest years on record is 1998. Higher temperatures today are largely sustained by increased atmospheric concentrations of greenhouse gases, especially carbon dioxide. These gases absorb infrared radiation emitted by Earth and release that energy into the atmosphere rather than allowing it to escape to space. As their atmospheric concentration has increased, the amount of energy "trapped" by these gases has led to higher temperatures. The carbon dioxide level in the atmosphere was about 285 parts per million in 1880, when the GISS global temperature record begins. By 1960, the average concentration had risen to about 315 parts per million. Today it exceeds 390 parts per million and continues to rise at an accelerating pace.
  
  The temperature analysis produced at GISS is compiled from weather data from more than 1,000 meteorological stations around the world, satellite observations of sea surface temperature and Antarctic research station measurements. A publicly available computer program is used to calculate the difference between surface temperature in a given month and the average temperature for the same place during 1951 to 1980. This three-decade period functions as a baseline for the analysis. The resulting temperature record is very close to analyses by the Met Office Hadley Centre in the United Kingdom and the National Oceanic and Atmospheric Administration's National Climatic Data Center in Asheville, N.C. Hansen said he expects record-breaking global average temperature in the next two to three years because solar activity is on the upswing and the next El Niño will increase tropical Pacific temperatures. The warmest years on record were 2005 and 2010, in a virtual tie. "It's always dangerous to make predictions about El Niño, but it's safe to say we'll see one in the next three years," Hansen said. "It won't take a very strong El Niño to push temperatures above 2010."
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  The above story is reprinted from materials provided by NASA.
  

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  New Melt Record for Greenland Ice Sheet: 'Exceptional' Season Stretched Up to 50 Days Longer Than Average
  http://www.sciencedaily.com/releases/2011/01/110121144011.htm
  
  ScienceDaily (Jan. 21, 2011) — New research shows that 2010 set new records for the melting of the Greenland Ice Sheet, expected to be a major contributor to projected sea level rises in coming decades.
  
  "This past melt season was exceptional, with melting in some areas stretching up to 50 days longer than average," said Dr. Marco Tedesco, director of the Cryospheric Processes Laboratory at The City College of New York (CCNY -- CUNY), who is leading a project studying variables that affect ice sheet melting. "Melting in 2010 started exceptionally early at the end of April and ended quite late in mid- September."  The study, with different aspects sponsored by World Wildlife Fund (WWF), the National Science Foundation and NASA, examined surface temperature anomalies over the Greenland ice sheet surface, as well as estimates of surface melting from satellite data, ground observations and models. In an article published in Environmental Research Letters, Professor Tedesco and co-authors note that in 2010, summer temperatures up to 3C above the average were combined with reduced snowfall. The capital of Greenland, Nuuk, had the warmest spring and summer since records began in 1873. Bare ice was exposed earlier than the average and longer than previous years, contributing to the extreme record. "Bare ice is much darker than snow and absorbs more solar radiation," said Professor Tedesco. "Other ice melting feedback loops that we are examining include the impact of lakes on the glacial surface, of dust and soot deposited over the ice sheet and how surface meltwater affects the flow of the ice toward the ocean."  WWF climate specialist Dr. Martin Sommerkorn said "Sea level rise is expected to top 1 metre by 2100, largely due to melting from ice sheets. And it will not stop there -- the longer we take to limit greenhouse gas production, the more melting and water level rise will continue."
  
  Dr. Tedesco's continuing research on ice sheets can be followed on www.cryocity.org .
  
  For more on Arctic climate change, visit www.panda.org/arctic

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  Global Carbon Emissions Reach Record 10 Billion Tons, Threatening 2 Degree Target
  http://www.sciencedaily.com/releases/2011/12/111204144648.htm
  
  ScienceDaily (Dec. 4, 2011) ­ Global carbon dioxide emissions from burning fossil fuels have increased by 49 per cent in the last two decades, according to the latest figures by an international team, including researchers at the Tyndall Centre for Climate Change Research, University of East Anglia.Published Dec. 4 in the journal Nature Climate Change, the new analysis by the Global Carbon Project shows fossil fuel emissions increased by 5.9 per cent in 2010 and by 49 per cent since 1990 -- the reference year for the Kyoto protocol.  On average, fossil fuel emissions have risen by 3.1 per cent each year between 2000 and 2010 -- three times the rate of increase during the 1990s. They are projected to continue to increase by 3.1 per cent in 2011.  Total emissions -- which combine fossil fuel combustion, cement production, deforestation and other land use emissions -- reached 10 billion tonnes of carbon* in 2010 for the first time. Half of the emissions remained in the atmosphere, where CO2 concentration reached 389.6 parts per million. The remaining emissions were taken up by the ocean and land reservoirs, in approximately equal proportions.  Rebounding from the global financial crisis of 2008-09 when emissions temporarily decreased, last year's high growth was caused by both emerging and developed economies. Rich countries continued to outsource part of their emissions to emerging economies through international trade.  Contributions to global emissions growth in 2010 were largest from China, the United States, India, the Russian Federation and the European Union. Emissions from the trade of goods and services produced in emerging economies but consumed in the West increased from 2.5 per cent of the share of rich countries in 1990 to 16 per cent in 2010. In the UK, fossil fuel CO2 emissions grew 3.8 per cent in 2010 but were 14 per cent below their 1990 levels. However, emissions from the trade of goods and services grew from 5 per cent of the emissions produced locally in 1990 to 46 per cent in 2010 -- overcompensating the reductions in local emissions. Emissions in the UK were 20 per cent above their 1990 levels when emissions from trade are taken into account.  "Global CO2 emissions since 2000 are tracking the high end of the projections used by the Intergovernmental Panel on Climate Change, which far exceed two degrees warming by 2100," said co-author Prof Corinne Le Quéré, director of the Tyndall Centre for Climate Change Research and professor at the University of East Anglia. "Yet governments have pledged to keep warming below two degrees to avoid the most dangerous aspects of climate change such as widespread water stress and sea level rise, and increases in extreme climatic events.  "Taking action to reverse current trends is urgent."  Lead author Dr Glen Peters, of the Centre for International Climate and Environmental Research in Norway, said: "Many saw the global financial crisis as an opportunity to move the global economy away from persistent and high emissions growth, but the return to emissions growth in 2010 suggests the opportunity was not exploited."  Co-author Dr Pep Canadell, executive director of the Global Carbon Project, added: "The global financial crisis has helped developed countries meet their production emission commitments as promised in the Kyoto Protocol and Copenhagen Accord, but its impact has been short-lived and pre-existing challenges remain."
  
  * Values reported here are in billion tonnes of carbon. To convert emissions to billion tonnes of CO2, multiply the value by 3.67.
  
  
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  Story Source:
  The above story is reprinted from materials provided by University of East Anglia.
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  Journal Reference:
  Glen P. Peters, Gregg Marland, Corinne Le Quéré, Thomas Boden, Josep G. Canadell, Michael R. Raupach. Rapid growth in CO2 emissions after the 2008–2009 global financial crisis. Nature Climate Change, 2011; DOI: 10.1038/nclimate1332

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• 2010 Spike in Greenland Ice Loss Lifted Bedrock, GPS Reveals

  http://www.sciencedaily.com/releases/2011/12/111209123214.htm
  
  ScienceDaily (Dec. 9, 2011) ­ An unusually hot melting season in 2010 accelerated ice loss in southern Greenland by 100 billion tons -- and large portions of the island's bedrock rose an additional quarter of an inch in response.  That's the finding from a network of nearly 50 GPS stations planted along the Greenland coast to measure the bedrock's natural response to the ever-diminishing weight of ice above it.  Every year as the Greenland Ice Sheet melts, the rocky coast rises, explained Michael Bevis, Ohio Eminent Scholar in Geodynamics and professor in the School of Earth Sciences at Ohio State University. Some GPS stations around Greenland routinely detect uplift of 15 mm (0.59 inches) or more, year after year. But a temperature spike in 2010 lifted the bedrock a detectably higher amount over a short five-month period -- as high as 20 mm (0.79 inches) in some locations.  In a presentation December 9 at the American Geophysical Union meeting in San Francisco, Bevis described the study's implications for climate change.  "Pulses of extra melting and uplift imply that we'll experience pulses of extra sea level rise," he said. "The process is not really a steady process." 
  Because the solid earth is elastic, Bevis and his team can use the natural flexure of the Greenland bedrock to measure the weight of the ice sheet, just like the compression of a spring in a bathroom scale measures the weight of the person standing on it.  Bevis is the principal investigator for the Greenland GPS Network (GNET), and he's confident that the anomalous 2010 uplift that GNET detected is due to anomalous ice loss during 2010: "Really, there is no other explanation. The uplift anomaly correlates with maps of the 2010 melting day anomaly. In locations where there were many extra days of melting in 2010, the uplift anomaly is highest." In scientific parlance, a melting day "anomaly" refers to the number of extra melting days -- that is, days that were warm enough to melt ice -- relative to the average number of melting days per year over several decades.  In 2010, the southern half of Greenland lost an extra 100 billion tons of ice under conditions that scientists would consider anomalously warm.
  
  GNET measurements indicate that as that ice melted away, the bedrock beneath it rose. The amount of uplift differed from station to station, depending on how close the station was to regions where ice loss was greatest.  Southern Greenland stations that were very close to zones of heavy ice loss rose as much as 20 mm (about 0.79 inches) over the five months. Even stations that were located far away typically rose at least 5 mm (0.2 inches) during the course of the 2010 melting season. But stations in the North of Greenland barely moved at all.  From 2007 to 2009, GNET installed GPS stations in the bedrock that lay exposed around the ice sheet margins along the Greenland coast. The research team is using Earth's natural elasticity to "weigh" the ice. As previous Ohio State studies of Antarctica revealed, ice weighs down bedrock, and when the ice melts away, the bedrock rises measurably in response.  GNET and similar GPS networks around the world could thus allow scientists to continue to measure ice loss after the Gravity Recovery and Climate Experiment (GRACE) satellites are retired in 2015. (GRACE is a joint project of NASA and the German Aerospace Center.)
  Bevis' coauthors in the School of Earth Sciences at Ohio State include Abel K. Brown, Eric C. Kendrick, Jason E. Box, Dana John Caccamise, Hao Zhou, Jian Wang, and Terry J. Wilson.  Their colleagues include John M. Wahr of the University of Colorado, Boulder; Shfaqat Abbas Khan, Finn Bo Madsen, and Per Knudsen of the Danish Technical University in Copenhagen; Michael J Willis of Cornell University; Tonie M. van Dam and Olivier Francis of the University of Luxembourg; Bjorn Johns, Thomas Nylen, and Seth White of UNAVCO, Inc, in Boulder; Robin Abbott of CH2M HILL Polar Services, in Boulder; and Rene Forsberg of the Space Institute, Denmark.
  
  GNET is funded by the National Science Foundation.
  

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  Story Source:

  The above story is reprinted from materials provided by Ohio State University.

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• NASA Finds 2011 Ninth-Warmest Year On Record 
  http://www.sciencedaily.com/releases/2012/01/120119152353.htm

ScienceDaily (Jan. 19, 2012) ­ The global average surface temperature in 2011 was the ninth warmest since 1880, according to NASA scientists. The finding continues a trend in which nine of the 10 warmest years in the modern meteorological record have occurred since the year 2000.  NASA's Goddard Institute for Space Studies (GISS) in New York, which monitors global surface temperatures on an ongoing basis, released an updated analysis that shows temperatures around the globe in 2011 compared to the average global temperature from the mid-20th century. The comparison shows how Earth continues to experience warmer temperatures than several decades ago. The average temperature around the globe in 2011 was 0.92 degrees F (0.51 C) warmer than the mid-20th century baseline.  "We know the planet is absorbing more energy than it is emitting," said GISS Director James E. Hansen. "So we are continuing to see a trend toward higher temperatures. Even with the cooling effects of a strong La Niña influence and low solar activity for the past several years, 2011 was one of the 10 warmest years on record."  The difference between 2011 and the warmest year in the GISS record (2010) is 0.22 degrees F (0.12 C). This underscores the emphasis scientists put on the long-term trend of global temperature rise. Because of the large natural variability of climate, scientists do not expect temperatures to rise consistently year after year. However, they do expect a continuing temperature rise over decades.

The first 11 years of the 21st century experienced notably higher temperatures compared to the middle and late 20th century, Hansen said. The only year from the 20th century in the top 10 warmest years on record is 1998.  Higher temperatures today are largely sustained by increased atmospheric concentrations of greenhouse gases, especially carbon dioxide. These gases absorb infrared radiation emitted by Earth and release that energy into the atmosphere rather than allowing it to escape to space. As their atmospheric concentration has increased, the amount of energy "trapped" by these gases has led to higher temperatures.
The carbon dioxide level in the atmosphere was about 285 parts per million in 1880, when the GISS global temperature record begins. By 1960, the average concentration had risen to about 315 parts per million. Today it exceeds 390 parts per million and continues to rise at an accelerating pace.  The temperature analysis produced at GISS is compiled from weather data from more than 1,000 meteorological stations around the world, satellite observations of sea surface temperature and Antarctic research station measurements. A publicly available computer program is used to calculate the difference between surface temperature in a given month and the average temperature for the same place during 1951 to 1980. This three-decade period functions as a baseline for the analysis.  The resulting temperature record is very close to analyses by the Met Office Hadley Centre in the United Kingdom and the National Oceanic and Atmospheric Administration's National Climatic Data Center in Asheville, N.C.  Hansen said he expects record-breaking global average temperature in the next two to three years because solar activity is on the upswing and the next El Niño will increase tropical Pacific temperatures. The warmest years on record were 2005 and 2010, in a virtual tie.  "It's always dangerous to make predictions about El Niño, but it's safe to say we'll see one in the next three years," Hansen said. "It won't take a very strong El Niño to push temperatures above 2010."

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Story Source:

• The above story is reprinted from materials provided by NASA.