Climate Change Science [Strictly Moderated]

SCIENCE DISCUSSION ONLY

Geology, Geophysics, Oceanography, Meteorology etc.

Moderators: Calilasseia, ADParker

Climate Change Science [Strictly Moderated]

#1  Postby Macdoc » Mar 01, 2010 8:20 am


!
GENERAL MODNOTE
This thread is for discussing the science of climate change. It has the operating assumptions that climate change is happening, and that it has an anthropogenic origin. From the 2007 IPCC Summary for Policymakers:

The Intergovernmental Panel on Climate Change wrote:Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level...

Observational evidence from all continents and most oceans shows that many natural systems are being affected by regional climate changes, particularly temperature increases...

Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic GHG concentrations...

Discussions of the pros and cons of the science go here.

Climate change denial does not go here.

Members wanting to post general remarks denying climate change or its anthropogenic basis, or off-topic references to what your favourite journalist, politician or 'radio personality' says about it all, should post them in the Climate Science Denial thread, which can be found here.

This thread will be strictly moderated. Off-topic, inflammatory, irrational or non-science based posts will be either binned or moved to the Denial thread as appropriate. Continuing to post OT or inflammatory posts will invite moderator attention, guidance, and corrective action as required.

Members are invited to contact a forum moderator if they need further clarification, or to use the report system if posts need to be reviewed by staff.

This is hopefully a stickied continuation from the threads of the same name at Dawkins....

This thread is for Climate Science News articles only and not intended for discussions whether or not climate change occurs or whether there are conspiracies, political agendas etc



Here are the links to the threads from the dawkins science forum....all 115 pages of articles from main stream climate and science sources

Most current
http://forum.richarddawkins.net/viewtop ... =5&t=74571

previous thread

http://www.richarddawkins.net/forum/vie ... 8#p1739008

Would like to keep the same format without discussion but with full attribution etc pending mod approval.
Some of the other contributors are here as well...
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

Ads by Google


Re: Global Climate Change Science News

#2  Postby Macdoc » Mar 01, 2010 10:06 am

February 22, 2010 |

Despite Climategate, IPPC Mostly Underestimates Climate Change

Speaking at the annual meeting of the American Association for the Advancement of Science, James McCarthy of the Harvard Medical School Center for Health and the Global Environment noted that the IPCC usually errs on the conservative side. Steve Mirsky reports

Lost in the coverage of the so-called climategate email controversy is a key point about the IPCC’s track record of climate change estimates. James McCarthy is on the faculty of the Harvard Medical School Center for Health and the Global Environment. He spoke February 21st at the annual meeting of the American Association for the Advancement of Science in San Diego:

“If you were to go back and map the IPCC projection for sea level rise and temperature in 1990, look at it in 1995, look at it in 2000. In retrospect you would find that they were conservative. So we talk about errors. If you were to do two ledgers—here are IPCC overestimates, here are IPCC underestimates—over the 20 or so years that these assessments have been running, the underestimate ledger would be much larger than the overestimate.

Even with glitches—clearly erroneous editing or sloppy editing that led to these erroneous statements that got us in trouble recently.”

—Steve Mirsky

http://www.scientificamerican.com/podca ... d-10-02-22
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

Re: Global Climate Change Science News

#3  Postby Zukiwi » Mar 07, 2010 6:18 pm

Hey ! Happy to see you back on the job - was hoping for your always interesting links on Global Climate Change ! :cheers:
Last.fm
from Shitmydadsays- "No, I'm not a pessimist. At some point the world shits on everybody. Pretending it ain't shit makes you an idiot, not an optimist."
" Un peuple informé est un peuple libre !" - René Lévesque
User avatar
Zukiwi
 
Posts: 39
Age: 107
Female

Country: Québec Canada
Canada (ca)
Print view this post

Re: Global Climate Change Science News

#4  Postby Macdoc » Mar 09, 2010 2:28 am

Zukiwi wrote:Hey ! Happy to see you back on the job - was hoping for your always interesting links on Global Climate Change ! :cheers:

thanks
I'm currently in Africa for 4 months so Tarby is doing a fair amount of posting
thanks for the support
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

Aquatic 'dead zones' contributing to climate change

#5  Postby RichardPrins » Mar 11, 2010 9:52 pm

Aquatic 'dead zones' contributing to climate change
As oxygen-deprived waters increase, they emit more greenhouse gasses into atmosphere

Cambridge, Md. – 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.

"As the volume of hypoxic waters move towards the sea surface and expands along our coasts, their ability to produce the greenhouse gas nitrous oxide increases," explains Dr. Codispoti of the UMCES Horn Point Laboratory. "With low-oxygen waters currently producing about half of the ocean's net nitrous oxide, we could see an additional significant atmospheric increase if these 'dead zones' continue to expand."

Although present in minute concentrations in Earth's atmosphere, nitrous oxide is a highly potent greenhouse gas and is becoming a key factor in stratospheric ozone destruction. For the past 400,000 years, changes in atmospheric N2O appear to have roughly paralleled changes in carbon dioxide CO2 and have had modest impacts on climate, but this may change. Just as human activities may be causing an unprecedented rise in the terrestrial N2O sources, marine N2O production may also rise substantially as a result of nutrient pollution, warming waters and ocean acidification. Because the marine environment is a net producer of N2O, much of this production will be lost to the atmosphere, thus further intensifying its climatic impact.

Increased N2O production occurs as dissolved oxygen levels decline. Under well-oxygenated conditions, microbes produce N2O at low rates. But at oxygen concentrations decrease to hypoxic levels, these waters can increase their production of N2O.

N2O production rates are particularly high in shallow suboxic and hypoxic waters because respiration and biological turnover rates are higher near the sunlit waters where phytoplankton produce the fuel for respiration.

When suboxic waters (oxygen essentially absent) occur at depths of less than 300 feet, the combination of high respiration rates, and the peculiarities of a process called denitrification can cause N2O production rates to be 10,000 times higher than the average for the open ocean. The future of marine N2O production depends critically on what will happen to the roughly ten percent of the ocean volume that is hypoxic and suboxic.

"Nitrous oxide data from many coastal zones that contain low oxygen waters are sparse, including Chesapeake Bay," said Dr. Codispoti. "We should intensify our observations of the relationship between low oxygen concentrations and nitrous oxide in coastal waters."

The article "Interesting Times for Nitrous Oxide" appears in the March 12, 2010 edition of the journal Science.

The University of Maryland Center for Environmental Science is the University System of Maryland's environmental research institution. UMCES researchers are helping improve our scientific understanding of Maryland, the region and the world through its three laboratories – Chesapeake Biological Laboratory in Solomons, Appalachian Laboratory in Frostburg, and Horn Point Laboratory in Cambridge – and the Maryland Sea Grant College.
Image
Image
User avatar
RichardPrins
 
Posts: 1525
Age: 50

Netherlands (nl)
Print view this post

Re: Aquatic 'dead zones' contributing to climate change

#6  Postby FACT-MAN-2 » Mar 13, 2010 12:18 am

Rewnewable energy marches on ...


Italy to host Europe's biggest solar plant

Posted Thu Mar 11, 2010 11:04am PST
http://green.yahoo.com/news/afp/2010031 ... dison.html

Activists of the environmental group Greenpeace hold banners reading, "Go Solar" during a demonstration in Rome in 2009. Europe's most powerful solar power plant is set to start operations in Italy later this year, the US company building the installation on an area as large as 120 football pitches said on Thursday.(AFP/File/Andreas Solaro)

MILAN (AFP) - Europe's most powerful solar power plant is set to start operations in Italy later this year, the US company building the installation on an area as large as 120 football pitches said on Thursday.

The plant in Rovigo near Venice in northeast Italy will take up 850,000 square metres (9.15 million square feet) and produce 72 megawatts, SunEdison said in a statement announcing the start of construction.

The current biggest plant in Europe, located in Spain, produces 60 megawatts and the second biggest, in Germany, 50 megawatts, SunEdison said.

"The photovoltaic park in Rovigo province is a milestone in the development and establishment of solar energy in Italy," SunEdison's general manager for Italy, Liborio Francesco Nanni, said in a statement.

The total investment will be between 200 million and 250 million euros (273 million and 342 million dollars), the company said.

Energy production will begin in the second half of 2010 and the plant will be fully operational by the end of the year, said SunEdison, which is working on the project in conjunction with Spanish banking giant Santander.

During its first year of operations, the plant will cover the electricity needs of 17,000 households and will prevent the emission of 41,000 tonnes of carbon dioxide into the atmosphere.

SunEdison, a subsidiary of US company MEMC Electronic Materials, is the top solar power company in the United States and the third biggest in the world.

Italy is second to Germany for solar power production in Europe.
Capitalism is obsolete, yet we keep dancing with its corpse.

When will large scale corporate capitalism and government metamorphose to embrace modern thinking and allow us to live sustainably?
FACT-MAN-2
 
Name: Sean Rooney
Posts: 10001
Age: 85
Male

Country: Canada
Canada (ca)
Print view this post

Re: Global Climate Change Science News

#7  Postby Macdoc » Mar 17, 2010 8:24 pm

Global cooling, we hardly knew ya
Category: climate
Posted on: March 16, 2010 8:54 AM, by James Hrynyshyn

From our friends at NOAA's National Climatic Data Center, in Asheville, N.C., we learn the following:
The combined global land and ocean average surface temperature for February 2010 was 0.60°C (1.08°F) above the 20th century average of 12.1°C (53.9°F). This is the sixth warmest such value on record.

The combined global land and ocean average surface temperature for December 2009 - February 2010 was the fifth warmest on record for the season, 0.57°C (1.03°F) above the 20th century average of 12.1°C (53.8°F).

For the year to date, the combined global land and ocean surface temperature of 12.7°C (54.9°F) was the fifth warmest January-February period on record. This value is 0.60°C (1.08°F) above the 20th century average.

The worldwide ocean surface temperature for February 2010 was the second warmest on record for February, 0.54°C (0.97°F) above the 20th century average of 15.9°C (60.6°F).

The seasonal (December 2009 - February 2010) worldwide ocean surface temperature was also the second warmest on record, 0.54°C (0.97°F) above the 20th century average of 15.8°C (60.5°F).

In the Southern Hemisphere, both the February 2010 average temperature for land areas and the Hemisphere as a whole (land and ocean surface combined), represented the warmest February on record. The Southern Hemisphere ocean temperature tied with 1998 as the warmest February on record.

http://scienceblogs.com/islandofdoubt/2 ... y_knew.php
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

Ads by Google


Re: Global Climate Change Science News

#8  Postby ginckgo » Mar 19, 2010 12:30 am

I had wondered about the length of balmy days we've had, but I didn't realise it was a record.

The Age wrote: City's hot 100 smashes record for run of warm days
ADAM MORTON
March 19, 2010


MELBOURNE'S temperature has topped 20 degrees for the past 100 days straight, the longest stretch of its type in more than 150 years of measurement.

Yesterday's maximum of 31 degrees continued a run of 20-plus degree days that began on December 9 last year.

It has smashed the record of 78 days with a maximum of more than 20 degrees in the summer of December 2000-01.

The Bureau of Meteorology's head of climate analysis and prediction, David Jones, said forecasts suggested the string of days warmer than 20 degrees could extend for at least another seven days.

He said it was part of a longer warm period across the state extending back to last winter.

''The whole of Australia has been exceptionally warm, and the mean temperature across Victoria over the past nine months has been the warmest on record,'' Dr Jones said.

''It continues this storyline of a planet that continues to warm.''

The British Met Office has predicted that it was more likely than not that 2010 would be the world's hottest year on record due to global warming linked to greenhouse gas emissions and a warming of the tropical Pacific Ocean due to El Nino.


It's probably all just urban heat island effect, right?
Cape illud, fracturor

Mystical explanations are thought to be deep; the truth is that they are not even shallow. Nietzsche
User avatar
ginckgo
 
Posts: 1058
Age: 45
Male

Australia (au)
Print view this post

Global warming threatens plant diversity

#9  Postby RichardPrins » Mar 23, 2010 11:52 pm

Global warming threatens plant diversity
In the coming decades, climate change is set to produce worldwide changes in the living conditions for plants, whereby major regional differences may be expected to occur.

Thus today's cool, moist regions could in future provide habitats for additional species, and in arid and hot regions the climatic prerequisites for a high degree of plant diversity will deteriorate. This is the conclusion reached in a new study by scientists at the Universities of Bonn, Göttingen and Yale, and published in the Proceedings of the Royal Society London.

Dr. Jan Henning Sommer of Bonn University´s Nees Institute for Biodiversity of Plants asserts, "climate change could bring great confusion to the existing pattern of plant diversity, with scarcely predictable consequences for our ecosystems and mankind". The potential impact of climate change on global plant diversity has now, for the first time, been quantified and modeled on a regional basis. The researchers have investigated the numbers of plant species to be found in different regions under current climatic conditions, and the subsequent interrelationship they uncovered has now been applied to 18 different climate change scenarios for the year 2100.

However, the study does not permit any predictions regarding the degree to which the biodiversity of any given region will, in fact, adapt to new conditions or, in other words, whether additional species will migrate into favoured regions, or whether disadvantaged areas will in reality suffer mass losses of species. "That would be fortune-telling. The adaptability of species and their interactions in the ecosystem can, like human landuse, exert great influence on their distribution. This is a field about which we still know far too little", Sommer explains. Nevertheless, the published results do provide an important pointer to the likelihood of the scales of immigration or losses to be expected in given areas. (...)
Image
Image
User avatar
RichardPrins
 
Posts: 1525
Age: 50

Netherlands (nl)
Print view this post

Re: Global Climate Change Science News

#10  Postby RichardPrins » Mar 26, 2010 6:52 am

Pollution from Asia Circles Globe at Stratospheric Heights
ScienceDaily — The economic growth across much of Asia comes with a troubling side effect: pollutants from the region are being wafted up to the stratosphere during monsoon season. The new finding, in a study led by scientists at the National Center for Atmospheric Research, provides additional evidence of the global nature of air pollution and its effects far above Earth's surface.

The international study is being published March 26 in Science Express. It was funded by the National Science Foundation, NCAR's sponsor, together with NASA and the Canadian Space Agency.

Using satellite observations and computer models, the research team determined that vigorous summertime circulation patterns associated with the Asian monsoon rapidly transport air upward from the Earth's surface. Those vertical movements provide a pathway for black carbon, sulfur dioxide, nitrogen oxides, and other pollutants to ascend into the stratosphere, about 20-25 miles above the Earth's surface.

"The monsoon is one of the most powerful atmospheric circulation systems on the planet, and it happens to form right over a heavily polluted region," says NCAR scientist William Randel, the lead author. "As a result, the monsoon provides a pathway for transporting pollutants up to the stratosphere."

Once in the stratosphere, the pollutants circulate around the globe for several years. Some eventually descend back into the lower atmosphere, while others break apart.

The study suggests that the impact of Asian pollutants on the stratosphere may increase in coming decades because of the growing industrial activity in China and other rapidly developing nations. In addition, climate change could alter the Asian monsoon, although it remains uncertain whether the result would be to strengthen or weaken vertical movements of air that transport pollutants into the stratosphere.

Randel says more research is needed into the possible effects of the pollutants. When sulfur rises into the stratosphere, it can lead to the creation of small particles called aerosols that are known to influence the ozone layer. The monsoon transport pathway may also have effects on other gases in the stratosphere, such as water vapor, that affect global climate by influencing the amount of solar heat that reaches Earth.

Tracing the path of pollutants
Scientists have long known that air over the tropics moves upward between the lower atmosphere and the stratosphere, part of a large-scale pattern known as the Brewer-Dobson circulation. But Randel and his colleagues suspected that the monsoon might also transport air into the stratosphere during the Northern Hemisphere's summer months. This could explain satellite measurements showing anomalous levels of stratospheric ozone, water vapor, and other chemicals over Asia during summer.

To isolate the role of the monsoon on the stratosphere, the researchers focused on a chemical, hydrogen cyanide, that is produced largely as a result of the burning of trees and other vegetation. The parcels of air over the tropical ocean that are lifted to the stratosphere by the Brewer-Dobson circulation contain low amounts of hydrogen cyanide, which breaks up over the ocean. But air over land that gets lifted up by the monsoon contains high levels of the chemical, especially during times of year when Asia has widespread fires, many set to clear land for agriculture.

When they examined satellite measurements, the researchers detected significant amounts of hydrogen cyanide throughout the lower atmosphere and up into the stratosphere over the monsoon region. Furthermore, satellite records from 2004 to 2009 showed a pattern of increases in the chemical's presence in the stratosphere each summer, correlating with the timing of the monsoon. The observations also showed hydrogen cyanide, which can last in the atmosphere for several years before breaking up, moving over the tropics with other pollutants and then circulating globally.

The researchers then used computer modeling to simulate the movement of hydrogen cyanide and pollutants from other sources, including industrial activity. The model indicated that emissions of pollutants over a broad region of Asia, from India to China and Indonesia, were becoming entrained in the monsoon circulation and transported into the lower stratosphere.

"This is a vivid example of pollutants altering our atmosphere in subtle and far-reaching ways," Randel says. (...)
Image
Image
User avatar
RichardPrins
 
Posts: 1525
Age: 50

Netherlands (nl)
Print view this post

Re: Global Climate Change Science News

#11  Postby Macdoc » Mar 29, 2010 8:28 pm


CSIRO/BOM: Record heat/climate needs science focus


Melbourne warms to a record long, hot summer

Surfersvillage Global Surf News, 19 March, 2010 : - - Melbourne has recorded its 100th day in a row when the maximum temperature has exceeded 20 degrees Celsius. Forecasts suggest the record run may extend into next week, at least. The last time Melbourne recorded a maximum temperature of less than 20 degrees was 8 December last year.

Melbourne’s string of warm days far exceeds the previous record of 78 days, set between 29 December 2000 and 16 March 2001. Records in Melbourne date back to 1855.

Image

Melbourne’s record run reflects the very warm conditions that have been experienced across Victoria since the start of last winter. Victoria’s mean temperature for the nine months from June 2009 to February 2010 is 15.3 degrees, the highest on record, and is 1.4 degrees above the 1961-90 average. The previous record of 15.1 degrees was set in 1980.

Source BO


CSIRO/BOM: Record heat/climate needs science focus
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

Re: Global Climate Change Science News

#12  Postby Macdoc » Mar 30, 2010 8:43 pm

Here come the consequences....
Drought in China caused by climate change: experts
(Xinhua)
Updated: 2010-03-28 20:24

BEIJING - Meteorologists have attributed the once-in-a-century drought parching southwest China to climate change.

The drought has left more than 18 million residents and 11.7 million head of livestock suffering drinking-water shortages over a region encompassing the southwestern provinces of Yunnan, Guizhou, Sichuan, the Guangxi Zhuang Autonomous Region and the municipality of Chongqing, data from the Ministry of Civil Affairs showed.

"The direct reason for the drought is light rain and high temperatures," Ren Fuming, a leading expert at China's National Climate Center, told the latest edition of Outlook Weekly, a well-known magazine in China.

Ren's opinion was echoed by Zhang Peiqun, also a meteorologist with the center.

Zhang said the rainfall in worst-hit Yunnan since September last year is the lowest in about 50 years while the average temperature since the beginning of winter is the highest.

"The decreased rainfall during the rainy season led to less water in store and high temperatures resulted in greater evaporation, directly causing the severe drought," Zhang said.

Zhang said the reasons underlying it were the complicated ocean currents and anomalous atmospheric circulation.

Zhang said the lingering cold air mass that formed last September in the Qinghai-Tibet Plateau had fenced off the warm and moist currents from the Indian Ocean and the Bay of Bengal, and at the same time the cold air from the north has had difficulty reaching the Yunnan-Guizhou plateau hinterland.

"The cold and warm currents can't converge to produce rain, so there is little rain," Zhang said.

Sun Honglie, director of the national expert committee on climate change, told the magazine that he was inclined to believe that the drought was a result of anomalous atmospheric currents.

"It is not an environmental or ecological problem," he said. "But the drought is bound to have an impact on the ecological system."

Another expert, Chen Yiyu, an academic at the Chinese Academy of Sciences, also said the year has seen anomalous climate conditions globally and that the drought in China is part of the phenomenon.

Globally, climate-related natural disasters have climbed from less than 50 a year in the 1950s to between 350 and 450 a year in the 2000s. In 2009, extreme weather events affected 55 million people around the world, according to figures released by the UN International Strategy for Disaster Reduction (UNISDR).

http://www.chinadaily.com.cn/china/2010 ... 653182.htm
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

U.K. Panel Calls Climate Data Valid

#13  Postby RichardPrins » Mar 31, 2010 4:12 am

U.K. Panel Calls Climate Data Valid
LONDON (AP) — A parliamentary panel investigating allegations that scientists at one of the world’s leading climate research centers misrepresented data related to global warming announced Wednesday that it had found no evidence to support that charge.

But the panel, the Science and Technology Committee of the British House of Commons, did fault scientists at the University of East Anglia’s Climatic Research Unit and its director, Prof. Phil Jones, for the way they handled freedom of information requests from skeptics challenging the evidence of climate change.

The panel said that Professor Jones and his colleagues could have saved themselves a great deal of trouble by aggressively publishing all their data instead of worrying about how to stonewall their critics.

The lawmakers’ inquiry is the first of three to be opened in Britain since the dissemination in November of e-mail messages and data between the scientists that were apparently hacked from a computer system.

The lawmakers emphasized that nothing in the more than 1,000 stolen e-mail messages or in the ensuing controversy challenged the scientific consensus that “global warming is happening and that it is induced by human activity.”

At the same time, the lawmakers stressed that their report, written after only a single day of oral testimony, did not cover all the issues and that two other inquiries into the integrity of the science would be more thorough.

The lawmakers expressed sympathy with Professor Jones, whom Phil Willis, the committee’s chairman, said had been made a scapegoat for conflicts within the sphere of climate science.

“The focus on Professor Jones and the C.R.U. has been largely misplaced,” the report said.

The publication of the e-mail messages ahead of an international conference in Copenhagen on climate change set off an online furor, in which skeptics of human-made climate change referred to the controversy as “Climategate.”

The lawmakers noted that they decided to investigate the matter because of “the serious implications for U.K. science.”
Image
Image
User avatar
RichardPrins
 
Posts: 1525
Age: 50

Netherlands (nl)
Print view this post

Re: Global Climate Change Science News

#14  Postby Macdoc » Apr 01, 2010 1:27 am

Published online 31 March 2010 | Nature 464, 657 (2010) | doi:10.1038/464657a
News
River reveals chilling tracks of ancient flood
Water from melting ice sheet took unexpected route to the ocean.

Quirin Schiermeier

Image
The Younger Dryas flood 13,000 years ago could have emptied into the Arctic Ocean through the Mackenzie River delta.W. LYNCH/PHOTOLIBRARY.COM
A thousand years after the last ice age ended, the Northern Hemisphere was plunged back into glacial conditions. For 20 years, scientists have blamed a vast flood of meltwater for causing this 'Younger Dryas' cooling, 13,000 years ago. Picking through evidence from Canada's Mackenzie River, geologists now believe they have found traces of this flood, revealing that cold water from North America's dwindling ice sheet poured into the Arctic Ocean, from where it ultimately disrupted climate-warming currents in the Atlantic.

The researchers scoured tumbled boulders and gravel terraces along the Mackenzie River for signs of the meltwater's passage. The flood "would solve a big problem if it actually happened", says oceanographer Wally Broecker of Columbia University's Lamont-Doherty Earth Observatory in Palisades, New York, who was not part of the team.

Image
> larger image http://www.nature.com/news/2010/100331/ ... box/1.html
On page 740, the geologists present evidence confirming that the flood occurred (J. B. Murton et al. Nature 464, 740–743; 2010). But their findings raise questions about exactly how the flood chilled the planet. Many researchers thought the water would have poured down what is now the St Lawrence River into the North Atlantic Ocean, where the currents form a sensitive climate trigger. Instead, the Mackenzie River route would have funnelled the flood into the Arctic Ocean (see map).

The Younger Dryas was named after the Arctic wild flower Dryas octopetala that spread across Scandinavia as the big chill set in. At its onset, temperatures in northern Europe suddenly dropped 10 °C or more in decades, and tundra replaced the forest that had been regaining its hold on the land. Broecker suggested in 1989 that the rapid climate shift was caused by a slowdown of surface currents in the Atlantic Ocean, which carry warm water north from the Equator to high latitudes (W. S. Broecker et al. Nature 341, 318-321; 1989). The currents are part of the 'thermohaline' ocean circulation, which is driven as the cold and salty — hence dense — waters of the far North Atlantic sink, drawing warmer surface waters north.

Broecker proposed that the circulation was disrupted by a surge of fresh water that overflowed from Lake Agassiz, a vast meltwater reservoir that had accumulated behind the retreating Laurentide Ice Sheet in the area of today's Great Lakes. The fresh water would have reduced the salinity of the surface waters, stopping them from sinking.

“There's no way for that water to go out of the Arctic without going into the Atlantic.”

The theory is widely accepted. However, scientists never found geological evidence of the assumed flood pathway down the St Lawrence River into the North Atlantic; or along a possible alternative route southwards through the Mississippi basin. Now it is clear why: the flood did occur; it just took a different route.

The team, led by Julian Murton of the University of Sussex in Brighton, UK, dated sand, gravel and boulders from eroded surfaces in the Athabasca Valley and the Mackenzie River delta in northwestern Canada. The shapes of the geological features there suggest that the region had two major glacial outburst floods, the first of which coincides with the onset of the Younger Dryas. If the western margins of the Laurentide Ice Sheet lay just slightly east of their assumed location, several thousand cubic kilometres of water would have been able to flood into the Arctic Ocean.

"Geomorphic observations and chronology clearly indicate a northwestern flood route down the Mackenzie valley," says James Teller, a geologist at the University of Manitoba in Winnipeg, Canada, who took part in the study. But he thinks that the route raises questions about the climatic effects of the Lake Agassiz spill. "We're pretty sure that the water, had it flooded the northern Atlantic, would have been capable of slowing the thermohaline ocean circulation and produce the Younger Dryas cooling," he says. "The question is whether it could have done the same in the Arctic Ocean."

Broecker, however, says that the Arctic flood is just what his theory needed. He says that flood waters heading down the St Lawrence River might not have affected the thermohaline circulation anyway, because the sinking takes place far to the north, near Greenland. A pulse of fresh water into the Arctic, however, would ultimately have flowed into the North Atlantic and pulled the climate trigger there. "There's no way for that water to go out of the Arctic without going into the Atlantic," he says.

http://www.nature.com/news/2010/100331/ ... 4657a.html
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

Re: U.K. Panel Calls Climate Data Valid

#15  Postby ginckgo » Apr 01, 2010 2:30 am



The thing that always got me was, that even the 'worst' emails only contained statements about what the researchers would like to do to the deniers. But if they actually had followed through and systematically blocked rival publications, got people fired, etc, shouldn't there have been a flurry of back-slapping emails back and forth between the 'conspirators', saying "yay, we got that idiot neutered" or something?
Cape illud, fracturor

Mystical explanations are thought to be deep; the truth is that they are not even shallow. Nietzsche
User avatar
ginckgo
 
Posts: 1058
Age: 45
Male

Australia (au)
Print view this post

Ads by Google


Ocean Acidification: 'Evil Twin' Threatens World's Oceans

#16  Postby RichardPrins » Apr 01, 2010 8:09 pm

Ocean Acidification: 'Evil Twin' Threatens World's Oceans, Scientists Warn
ScienceDaily — The rise in human emissions of carbon dioxide is driving fundamental and dangerous changes in the chemistry and ecosystems of the world's oceans, international marine scientists have warned.

"Ocean conditions are already more extreme than those experienced by marine organisms and ecosystems for millions of years," the researchers say in the latest issue of the journal Trends in Ecology and Evolution.

"This emphasises the urgent need to adopt policies that drastically reduce CO2 emissions."

Ocean acidification, which the researchers call the 'evil twin of global warming', is caused when the CO2 emitted by human activity, mainly burning fossil fuels, dissolves into the oceans. It is happening independently of, but in combination with, global warming.

"Evidence gathered by scientists around the world over the last few years suggests that ocean acidification could represent an equal -- or perhaps even greater threat -- to the biology of our planet than global warming," co-author Professor Ove Hoegh-Guldberg of the ARC Centre of Excellence for Coral Reef Studies and The University of Queensland says.

More than 30% of the CO2 released from burning fossil fuels, cement production, deforestation and other human activities goes straight into the oceans, turning them gradually more acidic.

"The resulting acidification will impact many forms of sea life, especially organisms whose shells or skeletons are made from calcium carbonate, like corals and shellfish. It may interfere with the reproduction of plankton species which are a vital part of the food web on which fish and all other sea life depend," he adds.

The scientists say there is now persuasive evidence that mass extinctions in past Earth history, like the "Great Dying" of 251 million years ago and another wipeout 55 million years ago, were accompanied by ocean acidification, which may have delivered the deathblow to many species that were unable to cope with it.

"These past periods can serve as great lessons of what we can expect in the future, if we continue to push the acidity the ocean even further" said lead author, Dr. Carles Pelejero, from ICREA and the Marine Science Institute of CSIC in Barcelona, Spain.

"Given the impacts we see in the fossil record, there is no question about the need to immediately reduce the rate at which we are emitting carbon dioxide in the atmosphere," he said further.

"Today, the surface waters of the oceans have already acidified by an average of 0.1 pH units from pre-industrial levels, and we are seeing signs of its impact even in the deep oceans," said co-author Dr. Eva Calvo, from the Marine Science Institute of CSIC in Barcelona, Spain.

"Future acidification depends on how much CO2 humans emit from here on -- but by the year 2100 various projections indicate that the oceans will have acidified by a further 0.3 to 0.4 pH units, which is more than many organisms like corals can stand," Prof. Hoegh-Guldberg says.

"This will create conditions not seen on Earth for at least 40 million years."

"These changes are taking place at rates as much as 100 times faster than they ever have over the last tens of millions of years" Prof. Hoegh-Guldberg says.

Under such circumstances "Conditions are likely to become very hostile for calcifying species in the north Atlantic and Pacific over the next decade and in the Southern Ocean over the next few decades," the researchers warn.

Besides directly impacting on the fishing industry and its contribution to the human food supply at a time when global food demand is doubling, a major die-off in the oceans would affect birds and many land species and change the biology of Earth as a whole profoundly, Prof. Hoegh-Guldberg adds.
Image
Image
User avatar
RichardPrins
 
Posts: 1525
Age: 50

Netherlands (nl)
Print view this post

Re: Global Climate Change Science News

#17  Postby newolder » Apr 13, 2010 6:34 pm

Flying now:
[youtube]http://www.youtube.com/watch?v=p2qyiwt1_68[/youtube]
Geometric forgetting gives me loops. - Nima A-H
User avatar
newolder
 
Name: Albert Ross
Posts: 3843
Age: 6
Male

Country: Feudal Estate number 9
Print view this post

Re: Global Climate Change Science News

#18  Postby FACT-MAN-2 » Apr 20, 2010 3:24 pm

If it isn't one thing, it's another ...


Is this the end of migration?

Climate change is affecting bird behaviour at a staggering rate. Some 20 billion have already changed their flight plans


By Alasdair Fotheringham in Linares, Spain
Sunday, 18 April 2010
http://www.independent.co.uk/environmen ... 47724.html

It's rained three times as much as usual this winter in Andalusia, and almost every day unemployed amateur ornithologist Javier Caracuel has walked past a disused mining tower in the decaying industrial town of Linares and looked up, expecting the pair of white storks that nest there to have migrated south.
Yet despite the surrounding high noise levels – the tower, some 10 metres high, is jammed between a school and a street clogged with traffic – and Andalusia's wettest winter in decades, the storks have stayed put. And they're not alone. "There have always been a couple of storks at the top of the church spire down by the railway station, but I've never seen so many across town," Mr Caracuel explains, "and there are dozens more in the villages."
The changes in storks' behaviour that Mr Caracuel has observed in one near-forgotten mining town in north-eastern Andalusia are far from uncommon. At a recent high-level congress attended by 200 migration experts, leading Spanish ornithologist Miguel Ferrer estimated that 20 billion birds have changed their migrating habits in the last few decades. The biggest single identifiable reason behind such a massive behavioural shift, involving 70 per cent of the world's migrating birds is – surprise, surprise – climate change.

"Long-distance migrators are travelling shorter distances, shorter-distance migrators are becoming sedentary," says Mr Ferrer, who works for Spain's Higher Council for Scientific Research (CSIC) in the Doñana National Park, one of the key European "stopovers" in bird migration routes. "That has a knock-on effect on almost everything they do, from breeding habits to feeding habits to their genetic diversity, which in turn affects other organisms in their food chain. It's a huge behavioural change, forced on them by rising temperatures."
"Climate change and environmental change are simultaneously forcing migratory birds to adapt extremely quickly," says Ian Newton, a Royal Society member and lifelong researcher into the subject. But if the adaption process is necessarily far faster than the last comparable geophysical phenomenon, the Ice Age, this time round it may not be anywhere near as successful.
[...]


Edit: I had to snip parts of the article because of copyright issues. - Mazille
Capitalism is obsolete, yet we keep dancing with its corpse.

When will large scale corporate capitalism and government metamorphose to embrace modern thinking and allow us to live sustainably?
FACT-MAN-2
 
Name: Sean Rooney
Posts: 10001
Age: 85
Male

Country: Canada
Canada (ca)
Print view this post

Re: Global Climate Change Science News

#19  Postby FACT-MAN-2 » Apr 24, 2010 4:31 am

A most interesting event:


What Happened in Bolivia This Week Could Save Our Failing Democracies

When Morales invited "social movements and Mother Earth's defenders" to a new kind of climate summit, it was an attempt to build a base of power behind the right to survive


By Naomi Klein
April 23, 2010 |
http://www.alternet.org/story/146597/wh ... ies?page=1

It was 11 am and Evo Morales had turned a football stadium into a giant classroom, marshaling an array of props: paper plates, plastic cups, disposable raincoats, handcrafted gourds, wooden plates and multicolored ponchos. All came into play to make his main point: to fight climate change, "we need to recover the values of the indigenous people."
Yet wealthy countries have little interest in learning these lessons and are instead pushing through a plan that at its best would raise average global temperatures 2 degrees Celsius. "That would mean the melting of the Andean and Himalayan glaciers," Morales told the thousands gathered in the stadium, part of the World People's Conference on Climate Change and the Rights of Mother Earth. What he didn't have to say is that the Bolivian people, no matter how sustainably they choose to live, have no power to save their glaciers.

Bolivia's climate summit has had moments of joy, levity and absurdity. Yet underneath it all, you can feel the emotion that provoked this gathering: rage against helplessness.
[...]


Edit: I had to snip parts of the article because of copyright issues. - Mazille
Capitalism is obsolete, yet we keep dancing with its corpse.

When will large scale corporate capitalism and government metamorphose to embrace modern thinking and allow us to live sustainably?
FACT-MAN-2
 
Name: Sean Rooney
Posts: 10001
Age: 85
Male

Country: Canada
Canada (ca)
Print view this post

Re: Global Climate Change Science News

#20  Postby Macdoc » Apr 26, 2010 12:02 am

A lovely tale...


Science Story: the Making of a Sea Level Study

Filed under:

* Climate Science
* Instrumental Record

— group @ 6 April 2010
http://www.realclimate.org/index.php/archives/2010/04/science-story-the-making-of-a-sea-level-study/
User avatar
Macdoc
THREAD STARTER
 
Posts: 11010
Age: 69
Male

Country: Canada/Australia
Australia (au)
Print view this post

Next

Return to Earth Sciences

Who is online

Users viewing this topic: No registered users and 6 guests