@danon5,
clicked!
a little too wet to have clothes out on the line right now - hoping for a warm/cool sunny weekend
have a great end of week everyone!
November 19, 2009
Seas Grow Less Effective at Absorbing Emissions
By SINDYA N. BHANOO
The Earth’s oceans, which have absorbed carbon dioxide from fuel emissions since the dawn of the industrial era, have recently grown less efficient at sopping it up, new research suggests.
Emissions from the burning of fossil fuels began soaring in the 1950s, and oceans largely kept up, scientists say. But the growth in the intake rate has slowed since the 1980s, and markedly so since 2000, the authors of a study write in a report in Thursday’s issue of Nature.
The research suggests that the seas cannot indefinitely be considered a reliable “carbon sink” as humans generate heat-trapping gases linked to global warming.
The slowdown in the rise of the absorption rate resulted from a gradual change in the oceans’ chemistry, the study found. “The more carbon dioxide the ocean absorbs, the more acidic it becomes and the less carbon dioxide it can absorb,” said the study’s lead author, Samar Khatiwala, a research scientist at the Lamont-Doherty Earth Observatory of Columbia University and a professor at the Georgia Institute of Technology.
“It’s a small change in absolute terms,” Dr. Khatiwala said. “What I think is fairly clear and important in the long term is the trend toward lower values, which implies that more of the emissions will remain in the atmosphere.”
To calculate the slowdown, Dr. Khatiwala and his collaborators created a mathematical model using tens of thousands of measurements of seawater collected over the past 20 years, including temperature, salinity and the presence of manufactured chlorofluorocarbons as a reflection of industrial activity.
They then worked backward with the data to create a formula that estimated the accumulation of human-generated carbon dioxide in the oceans from 1765, the opening of the industrial era, to 2008.
Even as human-generated emissions of carbon dioxide increase, the oceans’ uptake rate growth appears to have dropped by 10 percent from 2000 to 2007, Dr. Khatiwala said.
The last major research effort to measure industrial carbon uptake in the oceans was published in a 2004 Science study led by Christopher Sabine.
His methodology was different but arrived at similar conclusions.
Dr. Sabine used carbon dioxide measurements taken by more than 100 cruise ships to come up with a single figure: the oceans’ total industrial carbon uptake until 1994.
Dr. Khatiwala’s approach provides estimates of ocean carbon storage for every year from 1765 to 2008.
“Sabine’s estimate was like a single fuzzy snapshot,” Dr. Khatiwala said. “We’ve gone from that to having a relatively short movie of what happened from the start of the industrial era.”
Dr. Sabine said he agreed with the analogy, pointing out that his estimate for uptake up to 1994 was very close to Dr. Khatiwala’s for that period.
“Even though the techniques are completely different, they are in consensus at the one point that we can compare them,” Dr. Sabine said.
Yet much work remains to be done to confirm the results and to expand upon them, Dr. Khatiwala said.
November 24, 2009
New Data Shed Light on Large-Animal Extinction
By NICHOLAS WADE
Whenever modern humans reached a new continent in the expansion from their African homeland 50,000 years ago, whether Australia, Europe or the Americas, all the large fauna quickly disappeared.
This circumstantial evidence from the fossil record suggests that people’s first accomplishment upon reaching new territory was to hunt all its all large animals to death. But apologists for the human species have invoked all manner of alternative agents, like climate change and asteroid impacts.
A careful analysis of lake deposits in New York and Wisconsin has brought new data to bear on this heated debate. A team led by Jacquelyn Gill, a graduate student at the University of Wisconsin, has uncovered a critical sequence of events that rules out some explanations for the extinction of the large animals and severely constrains others.
The first event documented by Ms. Gill and her colleagues is the pace of extinction in North America, known from other research to have affected all animal species over about 2,200 pounds and half of those weighing more than about 70 pounds, the weight of a large dog.
Ms. Gill found a clever proxy for these disappearances. A fungus known as Sporormiella has to pass through the digestive system to complete its life cycle, and its spores are found in animal dung. By measuring the number of spores in the lake deposits, the Wisconsin team documented the steady disappearance of large animals from 14,800 years to 13,700 years ago, they reported in Thursday’s issue of Science.
The next clue to emerge from the lake deposits was the pollen of new plants including broad-leaved trees like oak. This novel plant community seems to have emerged because it was released from being grazed by large mammals.
The third clue is a layer of fine charcoal grains, presumably from fires that followed the buildup of wood.
This sequence of events has direct bearing on the megafauna whodunit. First, it rules out as the cause an impact by an asteroid or comet that occurred 12,900 years ago " the animals were dead long before.
It also excludes the standard version of a more popular explanation, that of habitat loss due to climate change. The extinction of large animals occurred before the emergence of the new plant communities. Ms. Gill said that some other aspect of climate, like direct temperature change, could have been involved.
The third suspect to be cleared is the people of the Clovis culture, which first appeared some 13,000 years ago, well after the extinction event. The Clovis people have long been considered the first inhabitants of North America, which they probably reached by trekking across the land bridge that joined Siberia and Alaska during the last Ice Age.
So, do the new data exculpate humans of the murder of the North American mammoth? Not exactly. Butchered mammoth bones some 14,500 years old have been found in Wisconsin. There were evidently pre-Clovis people in North America, and they could have hunted the large animals to death.
But Ms. Gill is not yet willing to declare people guilty. “At this stage it’s too early to completely eliminate climate change,” she said.
Nor is it clear that the pre-Clovis people had the technology to take down large game like mammoths. Ms. Gill plans to analyze many more lake bottoms before rendering any final verdict.
@sumac,
Climate change could be one of the reasons for extinction, but as we've seen, when humans take over habitat, wildlife is the first to go.
We're seeing the same sort of behaviour with some states happily killing wolves. Hasn't much to do with domestic stock - orgainzations reimburse ranchers when an animal is taken by wolves - plus many ranchers cooperate with wildlife and defender groups.
So i can see where animals disappeared from the landscape because humans hunted them to extinction. Predator animals are especially targeted. Can't have them competing with humans for hunting 'rights'.
Rain, wind, and snow today. brrr
http://rainforest.care2.com/i?p=583091674
An interesting debate for years, maybe they've finally proven the Shroud is authentic? Certainly, a reminder of the horrific ways people were executed during the Roman occupation.
Researcher says text proves Shroud of Turin real
http://news.yahoo.com/s/ap/eu_italy_shroud_of_turin
clicked around
clicked past
clicked by
clicking in your neighbourhood next
have a lovely earthturn all
@ehBeth,
Stradee, it'll always be shrouded in mystery. hehehehe
@danon5,
Couldn't have said it better...
Wind, rain, and freezing cold today - I needed to laugh, thanks. Sitting at the computer working all day is well...work. Me eyeballs are beginning to droop.
I may not be posting often, but if you listen carefully, you will hear the clicking.
I would say hi to alex but my guess is that he will not see it. Hi anyway.
All clicked for the day.
November 21, 2009
Editorial
Tuna’s Death Spiral
The international commission that sets catch limits for tuna and other large migratory fish has failed, once again, to do what is necessary to give the prized bluefin tuna in the eastern Atlantic and Mediterranean a real chance to survive. Meeting in Brazil last week, the commission approved an annual quota of 13,500 metric tons for 2010, well below the present quota of 22,000 tons but not the complete moratorium recommended by the commission’s own scientists.
Scientists say that overharvesting has caused a 72 percent decline over 50 years among adult bluefin in the eastern Atlantic and the Mediterranean, the fish’s primary spawning grounds. The illegal catch sometimes equals the authorized quota. Most marine scientists believe the fishery should be shut down completely until the fish have reached sustainable levels.
The United States recommended what it hoped would be an acceptable interim compromise of 8,000 tons or lower. But American negotiators were outgunned by the Japanese " where bluefin tuna is the source of high-grade sushi " and by the European Union, whose politicians do pretty much what the big commercial fleets in France, Spain, Italy and other Mediterranean countries tell them to do and who apparently won’t really start worrying until the last fish has been caught.
There is only one honorable course left for the United States. That is to join with Monaco and other countries that have proposed listing the bluefin as an endangered species under an international law known as the Convention on International Trade in Endangered Species. The law effectively bars commercial trade in any listed species, and has been helpful in protecting other animals like elephants and whales.
The next meeting of the 175 nations that subscribe to the convention will take place in March 2010 in Doha, Qatar. Earlier this year, the United States expressed support for Monaco’s proposal and said it would change its mind only if the negotiations in Brazil established “responsible science-based quotas.” They did not, and the United States should stick to its guns.
@sumac,
clicked
reading
catching up on some of sumac's offerings
@ehBeth,
and a good earthturn to you too, Beth
late clicks today - so busy
good articles, sue
enjoy your day wildclickers
http://rainforest.care2.com/i?p=583091674
@sumac,
I see it, I see it. Hello back at you threefold. Hello, hey, and hi.
@alex240101,
Great going alex ------- Hello and Hi back atcha.
sumac, bet he didn't see this one !!!
Good fishy article, sumac - but sad. I think I'll take the sails out of my tuna appetite. It's BoyCod time - er, something like that. ((The fish of course, not the other stuff))
@sumac,
Me too! Resting up, staying in, fighting off sinuses!
All clicked, though!
@teenyboone,
Hi teeny and all.
All clicked down here in TX.
@danon5,
Very cold all day - rain and snow - brrr
My feet feel like they're living in an igloo.
Stay warm, wildclickers
http://rainforest.care2.com/i?p=583091674
@Stradee,
Clicked earlier. In between bouts of arguing with the sewing machine
@Stradee,
Okay it's Monday, I'm all clicked and reheating the chicken soup from last week, after I defrost it. Dank, cold and getting worse here as the "blue Monday" drags on. Testing Xmas tree lights, today. Already in the spirit! Happy clicking everyone!
