• Security incident: ISF was recently accessed by intruders. Please change your password, and change it anywhere else you used it. Read more

Climate News from the science press

Arctic Report Card: Region Continues to Warm at Unprecedented Rate

http://www.sciencedaily.com/releases/2010/10/101022071814.htm

<SNIP>
Among the 2010 highlights:

* Greenland is experiencing record-setting high temperatures, ice melt and glacier area loss;

* Summer sea ice continues to decline -- the 2009-2010 summer sea ice cover extent was the third lowest since satellite monitoring began in 1979, and sea ice thickness continues to thin. The 2010 minimum is the third lowest recorded since 1979, surpassed only by 2008 and the record low of 2007; and

* Arctic snow cover duration was at a record minimum since record-keeping began in 1966.

</SNIP>
Click to expand...
 
Is CO2 just an aerial fertiliser? Not necessarily.

DR GRAHAM PHILLIPS : Carbon dioxide is crucial for plant growth. Plants breathe in CO2 and convert the gas into usable energy.

DR ROS GLEADOW : Plants use carbon dioxide. It's a carbon catcher and storage system so you think if there's more carbon dioxide they would just capture and store more. But in fact that doesn't happen. Plants do grow faster at elevated carbon dioxide usually, but not as fast as you'd expect.

DR GRAHAM PHILLIPS : Ros Gleadow has been studying the effects of raised C02 on plant growth.

DR ROS GLEADOW : Leaves of plants grown at elevated carbon dioxide have a lot less protein than wheat, barley, rice, all of those in probably only 50 to 60 years time will have 15 to 20% less protein in them than they do now.

DR GRAHAM PHILLIPS : So why would a plant have less protein in a raised carbon dioxide environment? In the process of photosynthesis, plants convert carbon dioxide into sugars using a protein called RuBisCO to capture the CO2 from the atmosphere. If carbon dioxide levels increase, plants will need to produce less RuBisCO to capture the same amount of carbon dioxide. Less of this protein means a less nutritious meal. And the plant's extra resources can then be diverted into protecting the plant. Plants protect themselves using spines and thorns or make themselves less appetising by producing toxic chemicals. Eucalypts produce phenols.

DR ROS GLEADOW : In about 50 years time or even 100 years time eucalyptus leaves will have trouble supporting arboreal herbivores like koalas because the phenolic concentration will be too high and the protein level too low.

DR GRAHAM PHILLIPS : Phenols are one way that plants protect themselves from animal attack but there is another way, cyanide.

EMERITUS PROFESSOR HOWARD BRADBURY : If an insect comes and eats the leaf, then it immediately gets a nasty taste of bitter hydrogen cyanide so it goes somewhere else. So this is a really great mechanism for protecting the plant. And there's about 2,000 plants that use this mechanism including apples, apricots, peaches.
Click to expand...

http://www.abc.net.au/ra/innovations/stories/s2967862.htm
 
Variable southeast summer rainfall linked to climate change

http://pda.physorg.com/news/2010-10-variable-southeast-summer-rainfall-linked.html

A doubling of abnormally wet or dry summer weather in the southeastern United States in recent decades has come from an intensification of the summertime North Atlantic Subtropical High (NASH), or "Bermuda High."

And that intensification appears to be coming from global warming, according to a new analysis by a Duke University-led team of climate scientists.

<SNIP>
Click to expand...
 
Expanding croplands chipping away at world's carbon stocks

http://pda.physorg.com/news/2010-11-croplands-chipping-world-carbon-stocks.html

The tradeoff between agricultural production and maintaining nature's carbon reservoirs – native trees, plants and their carbon-rich detritus in the soil – is becoming more pronounced as more and more of the world's natural ecosystems succumb to the plow. The problem, experts say, is most acute in the tropics, where expanding agriculture often comes at the expense of the tropical forests that act as massive carbon sinks because of their rich diversity and abundance of plant life.

The seriousness of the problem is documented in the most comprehensive and fine-grained analysis of the world's existing carbon stocks and global crop yields. The study is published online this week (Nov. 1) in the Proceedings of the National Academy of Sciences (PNAS) by a team of researchers from the University of Wisconsin-Madison, the University of Minnesota, Stanford University, Arizona State University and The Nature Conservancy. The article is part of a special PNAS feature on climate mitigation and agricultural productivity in the tropics.

<SNIP>

Compared to the world's temperate regions, the tropics release nearly twice as much carbon to the atmosphere for each unit of land cleared, explains Paul C. West, a UW-Madison graduate student and the lead author of the new study. "Tropical forests store a tremendous amount of carbon, and when a forest is cleared, not only do you lose more carbon, but crop yields are not nearly as high as they are in temperate areas."

"This creates a kind of 'double whammy' for a lot of tropical agriculture: we have to clear carbon-rich ecosystems to create tropical croplands, and unfortunately they often have lower yields than temperate systems," says Jonathan Foley, director of the University of Minnesota's Institute on the Environment and a co-author on the study. "In terms of balancing the needs of food production and slowing carbon dioxide emissions, this is a tough tradeoff."

<SNIP>
Click to expand...
 
Water flowing through ice sheets accelerates warming, could speed up ice flow

http://pda.physorg.com/news/2010-11-ice-sheets.html

Melt water flowing through ice sheets via crevasses, fractures and large drains called moulins can carry warmth into ice sheet interiors, greatly accelerating the thermal response of an ice sheet to climate change, according to a new study involving the University of Colorado at Boulder.

The new study showed ice sheets like the Greenland Ice Sheet can respond to such warming on the order of decades rather than the centuries projected by conventional thermal models. Ice flows more readily as it warms, so a warming climate can increase ice flows on ice sheets much faster than previously thought, said the study authors.

"We are finding that once such water flow is initiated through a new section of ice sheet, it can warm rather significantly and quickly, sometimes in just 10 years, " said lead author Thomas Phillips, a research scientist with Cooperative Institute for Research in Environmental Sciences. CIRES is a joint institute between CU-Boulder and the National Oceanic and Atmospheric Administration.

<SNIP>
Click to expand...
 
Energy & Sustainability The Heat Was On: Atmospheric CO2 Triggered a Global Warming Event 40 Million Years Ago

In a new study scientists used "paleothermometers" to gauge CO2 and temperatures that prevailed during a long-lived primordial global warming event, and found CO2 to be the culprit


By Mike Orcutt November 4, 2010 29

http://www.scientificamerican.com/media/inline/the-heat-was-on-atmospheric_1.jpg
HOT TIMES: Electron microscopic picture of microfossils found in the drill cores. By studying the remains of such marine plankton, scientists gain an accurate perspective of past climate change. Image: Appy Sluijs

Atmospheric CO2 was the primary driver of a 400,000-year global warming event, known as the middle Eocene climatic optimum (MECO), according to a new study. The finding, which could help climatologists better understand the precise relationship between CO2 concentration and climate change today, is described in the November 5 issue of Science.
Click to expand...

http://www.scientificamerican.com/article.cfm?id=the-heat-was-on-atmospheric
 
Do you think that the connection between global warming and the weather is simple? See this:



A new video by potholer54.
 
Last edited:
Nor with the biome

Polar Bears Unlikely to Survive in Warmer World, Biologists Say

magnifier.png
enlarge


Climate change will force polar bears south, where they are unsuited for the diet. (Credit: Alan D. Wilson)

ScienceDaily (Nov. 24, 2010) — Will polar bears survive in a warmer world? UCLA life scientists present new evidence that their numbers are likely to dwindle.
As polar bears lose habitat due to global warming, these biologists say, they will be forced southward in search of alternative sources of food, where they will increasingly come into competition with grizzly bears.
To test how this competition might unfold, the UCLA biologists constructed three-dimensional computer models of the skulls of polar bears and grizzly bears -- a subspecies of brown bears -- and simulated the process of biting. The models enabled them to compare the two species in terms of how hard they can bite and how strong their skulls are.
"What we found was striking," said Graham Slater, a National Science Foundation-funded UCLA postdoctoral scholar in ecology and evolutionary biology and lead author of the research. "The polar bear and brown bear can bite equally hard, but the polar bear's skull is a much weaker structure."
The implication is that polar bears are likely to lose out in competition for food to grizzlies as warmer temperatures bring them into the same environments, because grizzlies' stronger skulls are better suited to a plant-rich diet, said Slater and Blaire Van Valkenburgh, UCLA professor of ecology and evolutionary biology and senior author of the research.
"The result for polar bears may be lower weight, smaller and fewer litters, less reproductive success, fewer that would survive to adulthood, and dwindling populations," Van Valkenburgh said. "Then you can get into an extinction vortex, where a small population becomes even smaller in a downward spiral to extinction.
Click to expand...

more
http://www.sciencedaily.com/releases/2010/11/101124085607.htm
 
BenBurch said:
I believe I was in quite the argument about the end-Permian here a while ago... Nice to be vindicated by further research!
Click to expand...

You're not particularly surprised though, are you? :)

The usual emeriti will be right onto this one, as soon as they've finished replacing the traditional view of the Venusian atmosphere. And re-breaking the Hockey-Stick (apparently the Wegman Report didn't quite do the job it was credited with at the time). And demonstrating a very low climate sensitivity despite the climate demonstrating a rather high one all around them. And showing how Milankovich cycles can drive ice-ages without a CO2 feedback (Lindzen has said they can but, like Fermat, has left out the details. Let's hope he doesn't drop off his perch before he can enlighten us).

It's just as well they're mostly retired because they certainly have their hands full, what with all that science and testifying before the US Congress, their FoxNews appearances, providing "balancing quotes" for journalists, and the constant demands of blogging. Their selfless dedication to the public good should be an example to us all.
 
shadron said:
Do you think that the connection between global warming and the weather is simple?
Click to expand...

In some cases it is. For instance, global warming leads to more water vapour in the atmosphere, leading to higher precipitation rates when it condenses. We're seeing plenty of examples of that in recent times.

When it comes to the incidence of hurricanes it isn't at all simple, but, frankly, that's not nearly as important a subject as people in New Orleans tend to think it is.
 
recession no relief in 2009

Ouch

Nov 24 2010

GENEVA—A report by the UN weather agency has found that greenhouse gas levels in the atmosphere reached record levels in 2009.

The World Meteorological Organization says efforts to reduce emissions of carbon dioxide, methane and nitrous oxide haven’t diminished the atmospheric concentration of these gases widely blamed for stoking global warming.

The Geneva-based agency says concentrations of carbon dioxide rose in 2009 by 1.6 parts per million, to 386.8 parts per million.

The pre-industrial carbon dioxide average was about 280 parts per million. The higher the concentration of greenhouse gases, the more heat is trapped in the atmosphere.

WMO said Wednesday that the recent economic slowdown hadn’t significantly affected emissions of greenhouse gases.
Click to expand...

http://www.thestar.com/news/science...-concentrations-reached-record-levels-in-2009
 
Once again, please remember that this thread is for posting news, not for engaging in general discussion.
Replying to this modbox in thread will be off topic  Posted By: Cuddles
 
Bering Sea Was Ice-Free and Full of Life During Last Warm Period, Study Finds

"Current observations show more rapid warming in the Arctic compared to other places on Earth and compared to what was expected based on global climate models.

Ravelo's team found evidence of similar amplified warming at the poles during the Pliocene Warm Period. Analysis of the sediment samples indicated that average sea surface temperatures in the Bering Sea were at least 5 degrees Celsius warmer than today, while average global temperatures were only 3 degrees warmer than today."
 
In past decade, clouds created positive climate feedback

http://pda.physorg.com/news/2010-12-decade-clouds-positive-climate-feedback.html

A Texas A&M scientist's study of 10 years of NASA and other data found that clouds likely responded to carbon dioxide-induced global warming by amplifying that warming.

This amplified response is what scientists call a "positive feedback." The uncertainty about the feedback clouds will exhibit to increased greenhouse gases and a warmer climate remains one of the most difficult problems in long-term climate prediction. This new research, to be published Dec. 10 by Andrew Dessler in Science, is the first to look at real-world observations of global clouds at low and high altitudes. And when Dessler did that he found evidence of a positive feedback, and evidence that despite the uncertainty levels, current climate models are doing a reasonable job simulating cloud feedback.

"We've used observations to show that clouds amplify the warming we get from carbon dioxide," Dessler said. "No one has really rigorously quantified this feedback, and that's basically what I've done. The cloud feedback is indeed positive. It does amplify the warming we get from greenhouse gases. The results suggest that our understanding and the models' simulation is actually quite good."

<SNIP>
Click to expand...
 
Warming Climate Means Red Deer Rutting Season Arrives Early

http://www.sciencedaily.com/releases/2011/01/110114100948.htm

ScienceDaily (Jan. 14, 2011) — Wild red deer on the Isle of Rum are rutting earlier in the year, a study shows. Scientists believe the annual rutting season on the Isle of Rum could be changing because of warming spring and summer temperatures. The study shows that the rutting and calving seasons are now up to two weeks earlier on average compared with 30 years ago.

The research was based on a 38-year study of the ecology of red deer on the Isle of Rum and used annual records of breeding success in more than 3,000 individually recognisable deer.

Scientists at the Universities of Cambridge and Edinburgh, who maintained the long-term research, say this provides rare evidence that warming temperatures are affecting the behaviour of British mammals.

<SNIP>
Click to expand...
 
You must log in or register to reply here.

Share this page

ISF - Join now!

Every member here is approved by hand. No bots, no spam, just people who care about evidence and honest debate.

Membership is free!

Create your free account

Back
Top Bottom