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Sore Throat
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Drought threatens Amazon, speeds global warming
 Sat Mar 07, 2009 5:33 am
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Drought threatens Amazon, speeds global warming: study
PARIS (AFP) — Drought is killing off trees in Brazil's fragile Amazon rain forest and depleting the region's carbon reservoirs -- an ecological double-whammy with devastating implications, according to a study published Thursday.
The Amazon's lush vegetation in a typical year absorbs nearly two billion tonnes of carbon dioxide, one of the chief culprits causing climate change.
But a 30-year study published by the journal Science found that the world's largest tropical rain forest is surprisingly sensitive to drought, and that the resulting loss of vegetation will have a greater-than-anticipated effect in causing a sharp spike in greenhouse gases.
The Amazon tree canopy which absorbs massive amounts of greenhouse gases often succumbs to the effects of dryness, thereby accelerating global warming by not absorbing CO2, scientists said.
Drought also accelerates the depletion of the region's carbon sinks, natural reservoirs that accumulate and store the chemical compound for an indefinite period.
Researchers said the total impact of the drought was an additional five billion tonnes of carbon dioxide in the atmosphere -- more than the combined annual emissions of Europe and Japan.
The research from more than 40 institutions around the world was gathered during the particularly harsh 2005 drought, which had a severe impact on the flora of the Amazon.
The drought that year dramatically reversed decades of carbon absorption, the researchers said.
"For years, the Amazon forest has been helping to slow down climate change. But relying on this subsidy from nature is extremely dangerous," said Professor Oliver Phillips of Britain's University of Leeds, the lead author of the study.
"If the Earth's carbon sinks slow or go into reverse, as our results show is possible, carbon dioxide levels will rise even faster. Deeper cuts in emissions will be required to stabilize our climate."
Visually, most of the Amazon showed little effects of the drought. "But our records prove tree death rates accelerated," Phillips said.
"Because the region is so vast, even small ecological effects can scale-up to a large impact on the planet's carbon cycle."
Scientists say the Amazon accounts for more than half of the world's rainforest, covering an area 25 times the size of the United Kingdom.
The study, which involved 68 scientists from 13 countries, found that various species of tropical palm trees are particularly vulnerable to drought, which suggests the risk to biodiversity caused by climate change.
The findings are especially sobering because climatologists predict the creation of a potentially devastating cycle in which the Amazon's hotter and more intense future dry seasons in turn lead to more greenhouse gas emissions and even more drought. |
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Sore Throat
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| A roomful of cynics
Sat Mar 07, 2009 5:38 am
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http://gristmill.grist.org/story/2009/3/6/95445/42836/
A roomful of cynics
A look at the non-experts speaking at Heartland Institute's denialist sideshow
Posted by Coby Beck
When the science behind Gore's CO2 "hockey stick" slaps you down, there's nothing like indulging in old-fashioned denialism.
What is to be done when the world's leading experts in a field come together in the largest, most extensively peer-reviewed inquiry in the history of science and arrive at a conclusion that is diametrically opposed to your own long-held worldview? Most of us would reevaluate our ideas so they actually mesh with reality. That's called learning.
But if you are the staunchly "free market," anti-regulation think tank called the Heartland Institute and the conclusion is that humanity must cooperate to get the world out of a worsening climate crisis ... well, then what you do is simply manufacture a conclusion that is more to your liking.
Make no mistake, this is what the Heartland Institute's "International Conference on Climate Change" is all about. Set to begin Sunday in New York, the gathering's guest list includes the standard roster of "scientist-denialists" -- a large group of "experts" who have never published a single peer-reviewed study in their lives, along with a handful of fringe researchers who do (though rarely) publish in the field of climate science. The conference tagline is: "Global Warming: was it ever really a crisis?" and the conclusion is predetermined. "Was it ever a crisis?" ... as if it isn't right now.
By conception, the Heartland gathering seeks to establish itself as an authoritative gathering of genuine experts in climate science. The claim the Heartland Institute makes is pretty simple: "more than 70 of the world's elite scientists specializing in climate issues" will be there.
So, Heartland says to the unsuspecting, the experts are all coming to this event, and they all say there is nothing to worry about. That actually makes the whole charade pretty easy to unmask.
We don't have to examine every particular scientific or pseudo-scientific argument that will be advanced during the conference (that's been done repeatedly), because the whole thrust of this conference is about who is attending, not what they are saying.
Heartland promises the "world's elite scientists specializing in climate issues." Really? Let's have a quick look at the top-billed attendees as described by conference's official agenda:
American astronaut Dr. Jack Schmitt.
William Gray, Colorado State University, leading researcher into tropical weather patterns.
Richard Lindzen, Massachusetts Institute of Technology, one of the world's leading experts in dynamic meteorology, especially planetary waves.
Stephen McIntyre, primary author of Climate Audit, a blog devoted to the analysis and discussion of climate data.[...]
Arthur Robinson, curator of a global warming petition.
Willie Soon, Harvard-Smithsonian Center for Astrophysics.
Roy Spencer, University of Alabama at Huntsville, principal research scientist and team leader on NASA's Aqua satellite.
Astronaut? I thought we were talking about climate!
But seriously, who are these people and should we rely on their views?
Jack Schmitt indeed has a Ph.D., but his educational training has nothing to do with climate. After earning his doctorate in geology, Schmitt became an astronaut (he walked on the moon) and later a Republican senator from New Mexico; he teaches engineering physics and promotes the acquisition of lunar resources for the private sector as chairman of Interlune Intermars Initiative Inc.
William Gray is a well-respected scientist in the field of hurricane prediction -- but that is weather forecasting, not climate science. He actually compared Al Gore's belief in global warming to Adolf Hitler's belief that Jews are subhuman.
Steve McIntyre has studied mathematics and economics and spent 30 years in the Canadian mining industry. He is a well-known face in the climate wars as founder of Climate Audit, a blog devoted to criticizing the work of several prominent climate scientists.
Arthur Robinson is the founder of the Oregon Institute of Science and Medicine, a paper-only "institution" with no students and no courses. He himself is a chemist by training; his claim to fame in the realm of climate change skepticism is that he created the "Oregon Petition," a fraudulent document that pretended to come from the National Academy of Sciences.
Willie Soon is an astrophysicist whose work on solar-based explanations for the current planetary warming is mostly published on the websites of the Marshall Institute, the Fraser Institute and the Science and Public Policy Institute, hardly reputable journals of climate science literature.
These, then, are the "world's elite scientists specializing in climate issues?" Or so the Heartland Institute hopes to trick you into believing.
I have not yet mentioned Richard Lindzen and Roy Spencer, who, by the way, disagree with Soon, Robinson, Gray and Schmitt. While these two legitimate climate scientists express doubt about the dangers of climate change, they both acknowledge that the world is warming and that it is due to human activity, primarily greenhouse gas emissions. Actually, this puts them at odds with most of their fellow panelists.
Lindzen is a fading star in climate research, as he hitched his wagon to the Iris Hypothesis, a proposed sort of natural thermostat for the earth that would supposedly counter any large, CO2-forced warming. Scientists trying to investigate Lindzen's theory have reached different conclusions, and Lindzen is no longer very active in publishing peer-reviewed research.
Similarly, Spencer gained notoriety with his analysis of satellite readings of atmospheric temperatures. For some years, this analysis disagreed markedly with what climate models predicted -- showing cooling rather than warming in the middle and upper troposphere. However, a few years ago, a series of errors and data problems were uncovered, and his latest work on this topic now shows tropospheric temperatures that are well in agreement with general model expectations -- these parts of the atmosphere are indeed warming along with the surface.
Aside from the star billings, who else is attending?
Looking at the listing on Heartland website, we see blogger Anthony Watts, a retired weatherman (meteorology is NOT the same as climatology!). And then there's Myron Ebell, Marlo Lewis, Fred Smith, Sam Kazman, Steve Milloy, and Chris Horner -- all from the extreme free market Competitive Enterprise Institute (the organization that tried to stage a "pro-coal" counter-demonstration early this week in Washington, DC.
Lawrence Solomon, a columnist at the conservative National Post in Canada, is on the list, and British aristocrat-turned-politician-turned-journalist-turned-skeptic Christopher Monckton will be there.
Hardly "the world's elite scientists specializing in climate issues." In fact, none of these experts is a trained climate scientist. In the community of actual experts, the consensus is:
The earth is rapidly warming (over .6 degrees celsius in the last century)
Human activities are the primary cause
Warming will continue and accelerate if greenhouse gas emissions continue unabated
But in the world of political persuasion, where message trumps reality, the Heartland Institute wants you to just gas up your SUV and not worry about a thing. Like damning with faint praise, far from undermining the scientific consensus, this list illustrates just how strong that consensus really is.
Beck is the principal author of the "How to Talk to a Climate Skeptic" series. |
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Sore Throat
Joined: 01 Sep 2000
Posts: 1798
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| Pronouncement of Global Warming’s Demise On Thin Ice
Tue Mar 10, 2009 4:07 am
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http://www.popsci.com/environment/article/2009-03/pronouncement-global-warming’s-demise-thin-ice
Pronouncement of Global Warming’s Demise On Thin Ice
What’s up with global warming? Has it given way to global cooling, as some are suggesting? Let’s take a look
By Dr. Bill Chameides
PopSci.com welcomes back Dr. Bill Chameides, dean of Duke’s Nicholas School of the Environment. Dr. Chameides blogs at The Green Grok to spark lively discussions about environmental science, keeping you in the know on what the scientific world is discovering and how it affects you – all in plain language and, hopefully, with a bit of fun. Now, PopSci.com partners with The Green Grok to bring you exclusive new blog posts a week before they hit the Grok's blog. Give it a read and get in on the discussion!
The changes in average global temperatures from 1850 to 2008 are illustrated below.
A warming trend since the early 1900s through today is clearly evident. The trend hasn’t been smooth and continuous, though; there were lots of blips and dips, and even an extended period, from the 1940s through the 1960s, without any warming (and perhaps even some cooling). But overall global temperatures have increased over the 100+ year period.
But what’s going on now? Is the globe still warming?
Do a Google search on “global cooling” and you’ll find lots of pronouncements that global warming has given way to cooling. Like this one, and this.
Even the Farmer’s Almanac appears to have gotten into the act.
Maybe here’s why?
Take a look at the graph below, which focuses on the last 20 years instead of the last 100. It’s easy to see why one might conclude that temperatures have been going down over the past 10 years. Do an experiment: Take your hand and cover up the graph to the left of 1998 – the year with the highest temperatures on record. It sure does look like temperatures have decreased over the past 10 years, doesn’t it?
But wait a second, why start with 1998? That’s kind of arbitrary. Suppose you covered up the graph to the left of 1996 (or 2000) instead of 1998 – a very different picture emerges. Similarly, if it were1992, and you looked back on temperatures in 1990 and 1991, you might have concluded that a cooling trend had started and you would have been wrong. So what’s going on?
Don’t confuse short-term temperature changes with climate change
It’s important not to confuse short-term or inter-annual temperature changes with longer-term changes in temperatures that are relevant to the issue of climate change, which occurs on decadal time scales. There are any number of factors that cause global temperatures to rise and fall from one year to the next. Solar activity is one – as the sun goes through its 11-year sunspot cycle, solar radiation goes up and down causing global temperatures to fluctuate up and down. El Nino and La Nina oscillations in the South Pacific Ocean also lead to relatively warm years (El Nino) and cool years (La Nina).
The years 1998 and 2005 are interesting to compare – these are the two warmest years on record. That 1998 was so warm is not surprising. It was a year with an unusually strong El Nino and with the sun close to its 11-year maximum. By comparison, the sun in 2005 was near the minimum in its cycle, and the year began with a weak El Nino that dissipated by late spring. Most scientists have concluded that 2005 was as warm as it was without the benefit of a solar maximum or strong El Nino because of extra warming from greenhouse gases, but that is an issue for another day.
Global warming from greenhouse gases does not occur in a vacuum; it occurs simultaneously with other factors that affect global temperatures, such as solar variations and El Nino/La Nina oscillations. These other factors can cause short-term ups and downs in global temperatures.
But the question for global warming is whether they cause a net temperature change. To determine that, you have to “filter out” the short-term fluctuations. Scientists commonly do this by using multi-year averages of the temperatures. For example, the solid black lines in the first graph shown at the top of the post are 5-year running means, with each point on the line representing an average of that year’s temperature, that of two years preceding it, and the two following it. In a sense it is a smoothed-out picture of the temperature changes with the year-to-year extremes averaged out.
So is the global climate on a cooling trend?
To answer that question, I segmented the temperature record into 5-year groupings starting from 2004–2008 and going backward, then calculated the average global temperature for each 5-year segment. The results are illustrated below by the dashed lines.
Through this lens, we see evidence of a slowing of the warming trend but not of cooling. The past five years (2004–2008) were on average warmer than the previous five years (1999–2003) , which were warmer than the previous 5 years, and so on down the series. However, the difference between the 2004–2008 average and the 1999-2003 averages is not statistically significant. No cooling there. OK, but some of you are probably still wondering why 2008 was such a cold year.
Two things:
1. The stars (so to speak) were apparently aligned to make 2008 a cold year. The Pacific Ocean was in a La Nina phase, which favors cold global temperatures, and the sun was going through (and by the way continues to go thorough) an unusually strong minimum in its 11-year cycle; and
2. Even so, 2008 was not that cold. 2008 was actually the eighth or ninth warmest year on record. How could 2008 be the eighth warmest despite La Nina and the solar cycle? Greenhouse gas warming anyone?
So, what about those pronouncements of a global cooling? I would have to categorize them as – how can I put this – myopic?
Climate Change 2: Average global temperatures from 1989 to 2008 using data from Climatic Research Unit and United Kingdom Meteorological Office Hadley Centre with averages over consecutive 5-year segments shown by the dotted lines.
Bill Chameides
Dean, Duke University
Nicholas School of the Environment
www.TheGreenGrok.com |
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Sore Throat
Joined: 01 Sep 2000
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| Carbon emissions creating acidic oceans not seen since dinos
Tue Mar 10, 2009 5:59 am
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http://www.guardian.co.uk/environment/2009/mar/10/carbon-emissions-oceans-copenhagen
Carbon emissions creating acidic oceans not seen since dinosaurs
Chemical change placing 'unprecedented' pressure on marine life and could cause widespread extinctions, warn scientists
David Adam, environment correspondent
guardian.co.uk
Human pollution is turning the seas into acid so quickly that the coming decades will recreate conditions not seen on Earth since the time of the dinosaurs, scientists will warn today.
The rapid acidification is caused by the massive amounts of carbon dioxide belched from chimneys and exhausts that dissolve in the ocean. The chemical change is placing "unprecedented" pressure on marine life such as shellfish and lobsters and could cause widespread extinctions, the experts say.
The study, by scientists at Bristol University, will be presented at a special three-day summit of climate scientists in Copenhagen, which opens today. The conference is intended to update the science of global warming and to shock politicians into taking action on carbon emissions.
The Bristol scientists cannot talk about their unpublished results until they are announced later today. But a summary of the findings seen by the Guardian predicts "dangerous" levels of ocean acidification and severe consequences for organisms called marine calcifiers, which form chalky shells.
It says: "We find the future rate of surface ocean acidification and environmental pressure on marine calcifiers very likely unprecedented in the past 65 million years." The scientists add that the situation in the deep sea is of even "greater concern".
The scientists compared the current acidification rate with a giant prehistoric release of greenhouse gas, which geologists know caused widespread extinction of deep water species.
The summary reads: "Because the rates of acidification between past and future are comparable, and [because] there was widespread extinction of benthic organisms [lowest living], one must conclude that a similar level of extinction is more likely than not in the future."
Concern about ocean acidification from carbon pollution has grown in recent years, but the issue receives much less attention than global warming — also caused by human carbon emissions.
The Bristol study is one of the first to predict the consequences of acid waters by looking at past events. It says future deep sea acidification must be limited to 0.2 pH units to avoid the worst effects. The pH of surface waters, where the CO2 is absorbed from the atmosphere, has fallen by about 0.1 units since the industrial revolution, though it will take longer for the acid to reach deeper water.
Ocean acidification is one of the key topics at the Copenhagen summit, with a series of presentations scheduled to examine the impacts.
Ken Caldeira, an expert on ocean acidification at the Carnegie Institution in California, will tell the conference that the next few decades could produce "profound" changes in the oceans. He will say: "The choice to continue emitting carbon dioxide means that we will be an agent of biological change of a force and magnitude exceeded only by the causes of the great mass extinction events. If we do not cut carbon dioxide emissions deeply and soon, the consequences of ocean acidification will stand out against the broad reaches of geologic time. Those consequences will remain embedded in the geologic record as testimony from a civilisation that had the wisdom to develop high technology, but did not develop the wisdom to use it wisely."
Other experts will report that acidification is already affecting marine life in the Arctic and Antarctic. They will also discuss a bizarre finding that acid waters carry sound more efficiently, so the ocean will be a much noisier place in future.
The conference comes ahead of a year of high-level political discussions on climate change, which culminate in international negotiations in Copenhagen in December, where officials will try to hammer out a successor to the Kyoto protocol.
Katherine Richardson, a marine biologist at the University of Copenhagen, who organised this week's event, has described it as "a deliberate attempt to influence policy". She said many scientists were concerned that politicians have not grasped the seriousness of the situation, despite increasingly gloomy predictions.
This week's meeting will publish an update to the 2007 report of the Intergovernmental Panel on Climate Change (IPCC). A number of studies published since the IPCC report was prepared show that carbon emissions are rising faster than expected and that existing greenhouse gas targets may not be enough to prevent catastrophic temperature rise.
It will also assess whether projected sea level rises have been underestimated, and if there is still a realistic chance that average global temperature rise can be limited to 2C. |
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Sore Throat
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| Sea rise 'to exceed projections'
Tue Mar 10, 2009 9:20 pm
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http://news.bbc.co.uk/2/hi/science/nature/7935159.stm
Sea rise 'to exceed projections'
By David Shukman
Environment correspondent, BBC News, Copenhagen
The global sea level looks set to rise far higher than forecast because of changes in the polar ice-sheets, a team of researchers has suggested.
Scientists at a climate change summit in Copenhagen said earlier UN estimates were too low and that sea levels could rise by a metre or more by 2100.
The projections did not include the potential impact of polar melting and ice breaking off, they added.
The implications for millions of people would be "severe", they warned.
Ten per cent of the world's population - about 600 million people - live in low-lying areas.
The UN's Intergovernmental Panel on Climate Change (IPCC), in its 2007 Fourth Assessment Report, had said that the maximum rise in sea level would be in the region of 59cm.
Professor Konrad Steffen from the University of Colorado, speaking at a press conference on Tuesday, highlighted new studies into ice loss in Greenland, showing it has accelerated over the last decade.
Professor Steffen, who has studied the Arctic ice for the past 35 years, told me: "I would predict sea level rise by 2100 in the order of one metre; it could be 1.2m or 0.9m.
"But it is one metre or more seeing the current change, which is up to three times more than the average predicted by the IPCC."
"It is a major change and it actually calls for action."
Dr John Church of the Centre for Australian Weather and Climate Research added: "The most recent research showed that sea level is rising by 3mm a year since 1993, a rate well above the 20th century average."
Ice flow
Professor Eric Rignot, a senior research scientist at Nasa's Jet Propulsion Laboratory, said that results gathered since the IPCC showed that melting and ice loss could not be overlooked.
"As a result of the acceleration of outlet glaciers over large regions, the ice sheets in Greenland and Antarctica are already contributing more and faster to sea level rise than anticipated," he observed.
Professor Stefan Ramstorf of the Potsdam Institute for Climate Impact Research said: "[color=yellowBased on past experience, I expect that sea level rise will accelerate as the planet gets hotter." [/color]
The forecasts by the team of scientists are critically important for coastal communities.
At Lowestoft, on the UK's east coast, the Environment Agency official in charge of coastal protection, David Kemp, said that even small rises in sea level could be overwhelming.
"Put bluntly, if it's 10cm below the height of the defence, then there's no problem," he told me.
"But if it's 10cm above the defence, then we could be looking at devastation.
"It looks very benign today but the North Sea can turn into a very ferocious beast."
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/7935159.stm |
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Sore Throat
Joined: 01 Sep 2000
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| Global warming may trigger carbon 'time bomb', scientist war
Wed Mar 11, 2009 4:07 am
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http://www.guardian.co.uk/environment/2009/mar/10/climate-change-copenhagen
Global warming may trigger carbon 'time bomb', scientist warns
Billions of tonnes of carbon dioxide and methane could be released from thawing Arctic soils, says climate researcher
David Adam in Copenhagen
Even modest amounts of global warming could trigger a carbon "time bomb" and release massive amounts of greenhouse gases from frozen Arctic soils, a new study has warned.
Philippe Ciais, a researcher with the Laboratory for Climate Sciences and the Environment in Gif-sur-Yvette, France, told the Copenhagen Climate Congress that billions of tonnes of carbon dioxide and methane could be freed by just a 2C average rise.
He said such a release of greenhouse gases could trigger an "explosive" reaction in the soil, with bacteria able to start decomposing giant stocks of frozen carbon. "You can call it a bacterial heat production effect if you are a pretentious scientist, or you can call it composting," he said.
Using computer models and measurements from Siberia, Ciais and his colleagues predicted a fifth of the carbon could be released by 2200, once soil temperatures reached about 8C higher than today's levels. A global average increase in air temperatures of 2C would mean significantly higher temperatures in the Arctic, and Ciais warned that a few unusually hot years could see soil temperatures reach the 8C threshhold.
He called for a global observation network to monitor permafrost, and said it was a "scandal" that there are only about 20 people measuring it worldwide. |
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Sore Throat
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| Ocean "Dead Zones" Spreading Rapidly as Humans Pol
Wed Mar 11, 2009 11:22 pm
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http://www.naturalnews.com/z025795.html
Ocean "Dead Zones" Spreading Rapidly as Humans Pollute the Planet
by David Gutierrez, staff writer
(NaturalNews) The number of "dead zones" in coastal regions around the world continues to rapidly increase, according to a study conducted by researchers from the Virginia Institute of Marine Science and the University of Gothenberg, and published in the journal Science.
"It's not sort of a local or regional problem, which is how it was thought of in the past," researcher Robert Diaz said. "It is actually a global problem."
Dead zones are areas where oxygen has become so depleted that little or no marine life is able to survive. They form when excessive plant nutrients, particularly nitrogen and phosphorus, run off from the coast and lead to an explosion of algae blooms. When this vastly increased biomass dies and sinks to the bottom, its decomposition leads to the proliferation of oxygen-consuming bacteria.
In some cases, this may lead to increased crowding pressure in other parts of the ocean.
"Fish are the best at avoiding dead zones," Diaz says. "When the oxygen starts to decline, they're smart - they leave, they don't hang around. Crabs and shrimp are pretty good at getting away, too, as are lobsters."
Many slower moving animals such as clams, worms and small crustaceans, however, simply die.
In the current study, researchers found that the number of dead zones has steadily increased from 39 at the end of the 1960s through 63 at the end of the 1970s, 132 at the end of the 1980s and 301 at the end of the 1990s to the current number of 405. The total area consumed by dead zones now measures no less than 95,000 square miles.
The major sources of the pollutants that produce dead zones are fertilizer runoff from industrial agriculture and nitrogen-based byproducts of fossil fuel use.
"Most of it is agricultural-based, but there is a lot of industrial nitrogen in there, too, if you consider electric generation," Diaz said.
Dead zones now function as one of the primary stresses on marine biodiversity, along with overfishing and habitat loss.
Sources for this story include: www.reuters.com. |
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| Global warming 'will be worse than expected' warns Stern
Sat Mar 14, 2009 12:04 am
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http://www.guardian.co.uk/environment/2009/mar/12/climate-change-scienceofclimatechange
Global warming 'will be worse than expected' warns Stern
Economist says his 2006 groundbreaking report underestimated risk and accuses governments of not being ready for consequences of 6C temperature rise
David Adam in Copenhagen
guardian.co.uk,
Politicians have failed to take on board the severe consequences of failing to cut world carbon emissions, Nicholas Stern, the economist who warned the government of the high cost of climate change, said today.
Stern told a meeting of climate change scientists in Copenhagen that the effects of global warming would be worse than he predicted in his seminal 2006 report on the economics of the problem. He said policy-makers needed to think more about the likely impact of severe temperature rises of 6C or more.
Speaking after a keynote speech at the conference, Stern said: "Do the politicians understand just how difficult it could be? Just how devastating 4, 5, 6 degrees centigrade would be? I think not yet. Looking back, the Stern review underestimated the risks and underestimated the damage from inaction."
His remarks echo concerns by other scientists at the meeting. Privately, many climate experts and officials say that the European target of limiting world temperature rise to 2C above pre-industrial levels is no longer realistic.
Steven Sherwood, a climate researcher at Yale university, will tell the conference later today that warming of 4C or more this century looks "increasingly likely".
Bob Watson, a former head of the Intergovernmental Panel on Climate Change (IPCC) and chief scientist at the environment department, has already warned that governments need to prepare for a 4C rise.
The 2007 report of the IPCC said that average temperatures could rise by up to 6C this century if no action were taken to curb greenhouse gas emissions. Many scientists say this could be an underestimate, because world emissions have grown faster than expected.
According to the 2006 Stern report, a rise of 4C would put between seven million and 300 million more people at risk of coastal flooding each year, there would be a 30-50% reduction in water availability in southern Africa and the Mediterranean, agricultural yields would decline by 15%-35% in Africa, and 20%-50% of animal and plant species would face extinction. Yesterday, scientists announced at the conference that a 4C rise would lead to the loss of 85% of the Amazon rainforest.
A 5C rise would mean that major cities such as New York, London and Tokyo would be threatened by a rise in sea levels and increases in ocean acidity would severely disrupt marine ecosystems and fisheries. An increase of more than 5C — equivalent to the amount of warming that occurred between the last ice age and today — is, according to the Stern report, "likely to lead to major disruption and large-scale movement of population". It said the effects would be "catastrophic" and "far outside human experience". |
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Sore Throat
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| Climate scenarios 'being realised'
Sat Mar 14, 2009 12:37 am
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http://news.bbc.co.uk/2/hi/science/nature/7940532.stm
Climate scenarios 'being realised'
By Matt McGrath
BBC environment reporter, Copenhagen
The worst-case scenarios on climate change envisaged by the UN two years ago are already being realised, say scientists at an international meeting.
In a statement in Copenhagen on their six key messages to political leaders, they say there is a increasing risk of abrupt or irreversible climate shifts.
Even modest temperature rises will affect millions of people, particularly in the developing world, they warn.
But, they say, most tools needed to cut carbon dioxide emissions already exist.
More than 2,500 researchers and economists attended this meeting designed to update the world on the state of climate research ahead of key political negotiations set for December this year.
New data was presented in Copenhagen on sea level rise, which indicated that the best estimates of the Intergovernmental Panel on Climate Change (IPCC) made two years ago were woefully out of date.
Scientists heard that waters could rise by over a metre across the world with huge impacts for hundreds of millions of people.
There was also new information on how the Amazon rainforest would cope with rising temperatures. A UK Meteorological Office study concluded there would be a 75% loss of tree cover if the world warmed by three degrees for a century.
The scientists hope that their conclusions will remove any excuses from the political process.
Dr Katherine Richardson, who chaired the scientific steering committee that organised the conference, said the research presented added new certainty to the IPCC reports.
"We've seen lots more data, we can see where we are, no new surprises, we have a problem."
"Mass migrations"
The meeting was also addressed by Lord Stern, the economist, whose landmark review of the economics of climate change published in 2006 highlighted the severe cost to the world of doing nothing.
He now says the report underestimated the scale of the risks, and the speed at which the planet is warming.
He urged scientists to speak out and tell the politicians what the world would be like if effective measures against global warming were not taken.
He said that if the world was to warm by 5C over the next century, there would be dramatic consequences for millions of people. Rising seas would make many areas uninhabitable leading to mass migrations and inevitably sparking violent conflict.
"You'd see hundreds of millions people, probably billions of people who would have to move and we know that would cause conflict, so we would see a very extended period of conflict around the world, decades or centuries as hundreds of millions of people move, " said Lord Stern.
"So I think it's very important that we understand the magnitude of the risk we are running."
He said that a new, effective global deal was desperately needed to avoid these dramatic scenarios - and the current global economic slowdown was in some ways a help.
"Action is rather attractive, inaction is inexcusable. It's an opportunity, given that resources will be cheaper now than in the future, now is the time to get the unemployed of Europe working on energy efficiency."
Lord Stern's views were echoed by Danish Prime Minister Anders Fogh Rasmussen.
"Business as usual is dead - green growth is the answer to both our climate and economic problems.
"I hope the whole world will join us and set a two degree goal as an ambition of a climate deal in Copenhagen," said Mr Rasmussen.
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/7940532.stm
Published: 2009/03/12 19:17:14 GMT |
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Sore Throat
Joined: 01 Sep 2000
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| Five Global Warming "Tipping Points"
Wed Mar 18, 2009 4:16 am
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http://news.nationalgeographic.com/news/2009/03/photogalleries/tipping-points-climate-change/
Five Global Warming "Tipping Points"
1. Amazon Shrinks 50 Percent
If global warming turns more than half the Amazon rain forest (pictured) into something other than rain forest by 2200, the change "will lead to potentially dangerous climate change," according to most of the climate experts who participated in a survey about global warming "tipping points" released on March 16, 2009.
Tipping points occur when a small change in one factor, a "driver," can cause a disproportionately large response in an overall system.
In the Amazon Basin, climate shifts may lead to less rainfall, causing a large loss of species diversity--crippling the forest's ability to help maintain the region's air quality, fresh water cycle, and atmospheric circulation.
Between 2005 and 2006, 43 international climate experts volunteered to evaluate each of five tipping points, presented here--specifically, judging the likelihood that achieving a tipping point would lead to potentially dangerous global warming.
"Even though there's a lot of uncertainty and ambiguity in the results, our analysis shows these are not low-probability events," lead study author Elmar Kriegler, of Germany's Potsdam Institute for Climate Impact Research, told National Geographic News.
Experts judged the likelihood of these tipping points to strongly increase with scenarios of potentially low, medium, and high levels of future global warming, according to the study in the journal Proceedings of the National Academy of Science this week.
—Christine Dell'Amore
2. Atlantic "Conveyor Belt" Disrupted
If the flow of ocean water worldwide is severely disrupted by an influx of fresh water from melting ice caps due to rising temperatures, potentially dangerous global warming may follow, according to a survey about climate change "tipping points" released in March 2009.
This part of the ocean "conveyor belt"—called the Atlantic meridional overturning circulation—transports warm water northward (above, ice ledges in the Norwegian Sea) and sends cold water south at depth.
But the potential freshwater disturbance could prevent ocean water from moving northward and may have a range of impacts on the environment, from reducing fish stocks to spawning stronger hurricanes.
Little data exists about such global warming tipping points, said lead study author Elmar Kriegler of Germany's Potsdam Institute for Climate Impact Research.
For the new study, Kreigler wanted to glean experts' opinions about the likelihood that these major changes would engender dangerous global warming. The results will ideally inform policy action, Kriegler added.
3. Greenland Largely Ice Free
If the world warms by 4 degrees Celsius (7.2 degrees Fahrenheit), the Greenland ice sheet (above, meltwater lakes and streams near Kangerlussuag) will almost unavoidably melt away--leading to potentially dangerous global warming, a majority of experts said in a March 2009 study.
An ice-free Greenland would cause up to about 20 to 23 feet (6 to 7 meters) of sea-level rise, threatening up to 300 million people with harmful floods, experts say.
(Related: "Photos: Huge Greenland Glacier Disintegrating.")
Of the five tipping points assessed in a recent survey of climate experts, the scientists showed the "highest concern" about the Greenland ice sheet, according to lead study author Elmar Kriegler of Germany's Potsdam Institute for Climate Impact Research.
The survey participants also judged the likelihood of these tipping points being achieved if the climate achieves low, medium, and high levels of future global warming.
4. El Niño Becomes Permanent
If El Niño--a periodic disruption of the ocean and atmosphere in the tropical Pacific--becomes the average state of the region's climate as global warming progresses, widespread shifts in precipitation patterns (above, homes slide into the sea during El Niño storms in Pacifica, California) will ensue, said a majority of scientists who responded to a climate survey released on March 16, 2009.
Such changes could bring increased drought to Southeast Asia and the Amazon Basin, experts say.
Likewise, the South American coast would likely be heavily slammed with increased floods and changes in the marine food web, which could hurt many fisheries, the study said.
5. West Antarctica Islands Revealed
If the ice sheet over West Antarctica (above, seas pound a calving Ross Ice Shelf) disintegrates due to rising temperatures--revealing islands that are currently buried--potentially dangerous global warming could result, a bulk of experts agreed in a March 2009 survey (West Antarctica map).
Already, warming temperatures have accelerated fast-moving ice streams, causing a rush of fresh water that may affect ocean ecosystems around Antarctica.
Increased meltwater from West Antarctica may also raise the world's sea level by up to 20 to 23 feet (6 to 7 meters), the study says. |
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Sore Throat
Joined: 01 Sep 2000
Posts: 1798
Location: x |
| Great polar melt-off feared
Sat Mar 21, 2009 4:00 am
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http://www.chicagotribune.com/news/local/chi-antarctica-climate-change-19mar19,0,7871508.story
Great polar melt-off feared
Global warming, human activity speed Antarctic thaw, experts say
By William Mullen | Tribune reporter
For the last 5 million years, the frozen polar ends of the Earth have melted on a regular basis, raising sea levels dramatically to heights that, if achieved today, would inundate most of the world's major cities and coastal areas where billions of people live.
Scientists studying those polar freeze/thaw cycles reported in two papers in Thursday's edition of the research journal Nature that it appears Earth is headed toward another thaw—and this time, it's being hurried along by carbon dioxide pollution in the atmosphere.
The research dealt specifically with the ice sheets that sit atop West Antarctica, which contain enough water that world sea levels would rise 16 feet if it all melted. Such a thaw would take a thousand years at least, a long time in human terms but a blink in geological time.
The new papers both drew on core samples extracted from the Antarctic Ocean floor in 2006 as part of the ANDRILL project, one of the largest scientific undertakings ever for the continent. The project involved 53 scientists and was co-directed by Northern Illinois University geologist Ross Powell.
By examining millions of years' worth of sediments, researchers found that the ice in West Antarctica collapsed and melted about every 40,000 years during the Pliocene epoch 3 to 5 million years ago—a time when there were warm spells "similar to those projected to occur over the next century," Powell said.
When the polar ice began melting on a massive scale, atmospheric carbon dioxide levels were up to around 400 parts per million, Powell said. "We are now at 386 parts per million and rising," he said, and it grows by one part per million every year.
The concern, he said, is that the current rise in carbon dioxide levels—driven by human activity over the last 200 years, mostly the burning of fossil fuels—is causing unprecedented global warming and putting West Antarctica on the fast track to melting.
The Earth's average annual temperature has risen 1.4 degrees Fahrenheit in the last 100 years, but over Antarctica, which holds 70 percent of the world's fresh water as ice, it has risen 4.5 degrees.
"Even if it might take a thousand years or more for the West Antarctic Ice Sheet to disappear, the melting before then could be significant enough that humans should really be taking note ... as we worry about our future generations," Powell said.
Natural polar freeze/thaw cycles occur because of a periodic shift in the tilt of the Earth's axis, known as the Milankovitch Cycle.
"The tilting changes the amount of radiation absorbed into each hemisphere of the Earth, depending on which hemisphere is tilted closest to the sun," said Powell. With the change comes a gradual buildup of atmospheric carbon dioxide that ANDRILL records show eventually caused drastic loss of ice in West Antarctica.
But now, human activity appears to be having its own effect on the world's climate by driving temperatures higher than they otherwise would be, said Northern Illinois University geologist Reed Scherer, also on the ANDRILL research team. Some climatologists believe global temperatures should even be slightly cooling at this time.
"If something is an external cycle, it should be predictable," Scherer said. "But it is much more complicated than that, and we seem to be throwing the pattern off balance now."
Also in Nature was a report from David Pollard of Pennsylvania State University and Robert DeConto of the University of Massachusetts, who used ANDRILL data to simulate Antarctic ice sheet variations over the past 5 million years.
The two climate modelers found that the ice sheet atop West Antarctica could move between full, intermediate and collapsed states over only a few thousand years.
Today, even a partial melt-off raising sea levels by 4 feet would put at risk an estimated half a billion people who live along shorelines.
DeConto said warming ocean temperatures play a key role in how fast polar ice melts, both the ice sheets and the floating ice shelves to which they are attached. The shelves extend for miles into the ocean around Antarctica.
"The next big step," said DeConto, "is to determine what is happening to the ocean temperatures under the ice shelves and around the ice sheet. We really need that information."
wmullen@tribune.com |
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Sore Throat
Joined: 01 Sep 2000
Posts: 1798
Location: x |
| Study: Arctic Sea Ice Melting Faster Than Expected
Fri Apr 03, 2009 11:13 pm
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http://www.huffingtonpost.com/2009/04/03/study-arctic-sea-ice-melt_n_182651.html
Study: Arctic Sea Ice Melting Faster Than Expected
DOLPH E. SCHMID
WASHINGTON — Arctic sea ice is melting so fast most of it could be gone in 30 years. A new analysis of changing conditions in the region, using complex computer models of weather and climate, says conditions that had been forecast by the end of the century could occur much sooner.
A change in the amount of ice is important because the white surface reflects sunlight back into space. When ice is replaced by dark ocean water that sunlight can be absorbed, warming the water and increasing the warming of the planet.
The finding adds to concern about climate change caused by human activities such as burning fossil fuels, a problem that has begun receiving more attention in the Obama administration and is part of the G20 discussions under way in London.
"Due to the recent loss of sea ice, the 2005-2008 autumn central Arctic surface air temperatures were greater than 5 degrees Celsius (9 degrees Fahrenheit) above" what would be expected, the new study reports.
That amount of temperature increase had been expected by the year 2070.
The new report by Muyin Wang of the Joint Institute for the Study of Atmosphere and Ocean and James E. Overland of the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory, appears in Friday's edition of the journal Geophysical Research Letters.
They expect the area covered by summer sea ice to decline from about 2.8 million square miles normally to 620,000 square miles within 30 years.
Last year's summer minimum was 1.8 million square miles in September, second lowest only to 2007 which had a minimum of 1.65 million square miles, according to the National Snow and Ice Data Center.
The Center said Arctic sea ice reached its winter maximum for this year at 5.8 million square miles on Feb. 28. That was 278,000 square miles below the 1979-2000 average making it the fifth lowest on record. The six lowest maximums since 1979 have all occurred in the last six years.
Overland and Wang combined sea-ice observations with six complex computer models used by the Intergovernmental Panel on Climate Change to reach their conclusions. Combining several computer models helps avoid uncertainties caused by natural variability.
Much of the remaining ice would be north of Canada and Greenland, with much less between Alaska and Russia in the Pacific Arctic.
"The Arctic is often called the Earth's refrigerator because the sea ice helps cool the planet by reflecting the sun's radiation back into space," Wang said in a statement. "With less ice, the sun's warmth is instead absorbed by the open water, contributing to warmer temperatures in the water and the air."
The study was supported by the NOAA Climate Change Program Office, the Institute for the Study of the Ocean and Atmosphere and the U.S. Department of Energy.
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On the Net:
NOAA: http://www.noaa.gov
Joint Institute for the Study of Atmosphere and Ocean: http://jisao.washington.edu/
National Snow and Ice Data Center: http://nsidc.org/
Geophysical Research Letters: http://www.agu.org/journals/gl/ |
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Sore Throat
Joined: 01 Sep 2000
Posts: 1798
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| Ice bridge ruptures in Antarctic
Mon Apr 06, 2009 3:38 pm
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http://news.bbc.co.uk/2/hi/science/nature/7984054.stm
Ice bridge ruptures in Antarctic
An ice bridge linking a shelf of ice the size of Jamaica to two islands in Antarctica has snapped.
Scientists say the collapse could mean the Wilkins Ice Shelf is on the brink of breaking away, and provides further evidence of rapid change in the region.
Sited on the western side of the Antarctic Peninsula, the Wilkins shelf has been retreating since the 1990s.
Researchers regarded the ice bridge as an important barrier, holding the remnant shelf structure in place.
Its removal will allow ice to move more freely between Charcot and Latady islands, into the open ocean.
European Space Agency satellite pictures had indicated last week that cracks were starting to appear in the bridge. Newly created icebergs were seen to be floating in the sea on the western side of the peninsula, which juts up from the continent towards South America's southern tip.
Professor David Vaughan is a glaciologist with the British Antarctic Survey who planted a GPS tracker on the ice bridge in January to monitor its movement.
He said the breaking of the bridge had been expected for some weeks and much of the ice shelf behind was likely to follow.
"We know that [the Wilkins Ice Shelf] has been completely or very stable since the 1930s and then it started to retreat in the late 1990s. But we suspect that it's been stable for a very much longer period than that," he told BBC News.
"The fact that it's retreating and now has lost connection with one of its islands is really a strong indication that the warming on the Antarctic is having an effect on yet another ice shelf."
While the break-up will have no direct impact on sea level because the ice is floating, it heightens concerns over the impact of climate change on this part of Antarctica.
Over the past 50 years, the peninsula has been one of the fastest warming places on the planet.
Many of its ice shelves have retreated in that time and six of them have collapsed completely (Prince Gustav Channel, Larsen Inlet, Larsen A, Larsen B, Wordie, Muller and the Jones Ice Shelf).
Separate research shows that when ice shelves are removed, the glaciers and landed ice behind them start to move towards the ocean more rapidly. It is this ice which can raise sea levels, but by how much is a matter of ongoing scientific debate.
Such acceleration effects were not included by the UN's Intergovernmental Panel on Climate Change (IPCC) when it made its latest projections on likely future sea level rise. Its 2007 assessment said ice dynamics were poorly understood.
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/7984054.stm
Published: 2009/04/05 07:13:59 GMT |
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Sore Throat
Joined: 01 Sep 2000
Posts: 1798
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| Obama to Look at Climate Engineering
Thu Apr 09, 2009 12:05 am
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http://online.wsj.com/article/SB123920773503201665.html
Obama to Look at Climate Engineering
Associated Press
WASHINGTON -- The president's new science adviser said Wednesday that global warming is so dire, the Obama administration is discussing radical technologies to cool Earth's air.
John Holdren told the Associated Press in his first interview since being confirmed last month that the idea of geoengineering the climate is being discussed. One such extreme option includes shooting pollution particles into the upper atmosphere to reflect the sun's rays. Mr. Holdren said such an experimental measure would only be used as a last resort.
"It's got to be looked at," he said. "We don't have the luxury of taking any approach off the table."
Mr. Holdren outlined several "tipping points" involving global warming that could be fast approaching. Once such milestones are reached, such as complete loss of summer sea ice in the Arctic, it increases chances of "really intolerable consequences," he said.
Twice in a half-hour interview, Mr. Holdren compared global warming to being "in a car with bad brakes driving toward a cliff in the fog."
At first, Mr. Holdren characterized the potential need to technologically tinker with the climate as just his personal view. However, he went on to say he has raised it in administration discussions.
Mr. Holdren, a 65-year-old physicist, is far from alone in taking geoengineering more seriously. The National Academy of Science is making climate tinkering the subject of its first workshop in its new multidiscipline climate challenges program. The British parliament has also discussed the idea.
The American Meteorological Society is crafting a policy statement on geoengineering that says "it is prudent to consider geoengineering's potential, to understand its limits and to avoid rash deployment."
Last week, Princeton scientist Robert Socolow told the National Academy that geoengineering should be an available option in case climate worsens dramatically.
But Mr. Holdren noted that shooting particles into the air -- making an artificial volcano as one Nobel laureate has suggested -- could have grave side effects and would not completely solve all the problems from soaring greenhouse gas emissions. So such actions could not be taken lightly, he said.
Still, "we might get desperate enough to want to use it," he added.
Another geoengineering option he mentioned was the use of so-called artificial trees to suck carbon dioxide -- the chief human-caused greenhouse gas -- out of the air and store it. At first that seemed prohibitively expensive, but a re-examination of the approach shows it might be less costly, he said. |
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Sore Throat
Joined: 01 Sep 2000
Posts: 1798
Location: x |
| Obama Global Warming Plan Involves Cooling Air
Thu Apr 09, 2009 12:36 am
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http://www.huffingtonpost.com/2009/04/08/obama-global-warming-plan_n_184657.html
Obama Global Warming Plan Involves Cooling Air
SETH BORENSTEIN | April 8, 2009
WASHINGTON — Tinkering with Earth's climate to chill runaway global warming _ a radical idea once dismissed out of hand _ is being discussed by the White House as a potential emergency option, the president's new science adviser said Wednesday.
That's because global warming is happening so rapidly, John Holdren told The Associated Press in his first interview since being confirmed last month.
The concept of using technology to purposely cool the climate is called geoengineering. One option raised by Holdren and proposed by a Nobel Prize-winning scientist includes shooting pollution particles into the upper atmosphere to reflect the sun's rays.
Using such an experimental measure is only being thought of as a last resort, Holdren said.
"It's got to be looked at," he said. "We don't have the luxury ... of ruling any approach off the table."
His concern is that the United States and other nations won't slow global warming fast enough and that several "tipping points" could be fast approaching. Once such milestones are reached, such as complete loss of summer sea ice in the Arctic, it increases chances of "really intolerable consequences," he said.
Twice in a half-hour interview, Holdren compared global warming to being "in a car with bad brakes driving toward a cliff in the fog."
He and many experts believe that warming of a few degrees more would lead to disastrous drought conditions and food shortages in some regions, rising seas and more powerful coastal storms in others.
At first, Holdren characterized the potential need to technologically tinker with the climate as just his personal view. However, he went on to say he has raised it in administration discussions.
"We're talking about all these issues in the White House," Holdren said. "There's a very vigorous process going on of discussing all the options for addressing the energy climate challenge."
Holdren said discussions include Cabinet officials and heads of sub-Cabinet level agencies, such as NASA and the Environmental Protection Agency.
The 65-year-old physicist is far from alone in taking geoengineering seriously. The National Academy of Sciences is making it the subject of the first workshop in its new climate challenges program for policymakers, scientists and the public. The British Parliament has also discussed the idea. At an international meeting of climate scientists last month in Copenhagen, 15 talks dealt with different aspects of geoengineering.
The American Meteorological Society is crafting a policy statement that says "it is prudent to consider geoengineering's potential, to understand its limits and to avoid rash deployment."
Last week, Princeton scientist Robert Socolow told the National Academy that geoengineering should be an available option in case climate worsens dramatically.
Holdren, a 1981 winner of a MacArthur Foundation "genius" grant, outlined these possible geoengineering options:
_ Shooting sulfur particles (like those produced by power plants and volcanoes, for example) into the upper atmosphere, an idea that gained steam when it was proposed by Nobel laureate Paul Crutzen in 2006. It would be "basically mimicking the effect of volcanoes in screening out the incoming sunlight," Holdren said.
_ Creating artificial "trees" _ giant towers that suck carbon dioxide out of the air and store it.
The first approach would "try to produce a cooling effect to offset the heating effect of carbon dioxide and other greenhouse gases," Holdren said.
But he said there could be grave side effects. Studies suggest that might include eating away a large chunk of the ozone layer above the poles and causing the Mediterranean and the Mideast to be much drier.
And those are just the predicted problems. Scientists say they worry about side effects that they don't anticipate.
While the idea could strike some people as too risky, the Obama administration could get unusual support on the idea from groups that have often denied the harm of global warming in the past.
The conservative think tank American Enterprise Institute has its own geoengineering project, saying it could be "feasible and cost-effective." And Cato Institute scholar Jerry Taylor said Wednesday: "Very few people would rule out geoengineering on its face."
Holdren didn't spell out under what circumstances such extreme measures might ever be called for. And he emphasized they are not something to rely on.
"It would be preferable by far," he said, "to solve this problem by reducing emissions of greenhouse gases."
Yet there is already significant opposition building to the House Democratic leaders' bill aimed at achieving President Barack Obama's goal of cutting greenhouse gas emissions 20 percent by 2020 and 80 percent by 2050.
Holdren said temperatures should be kept from rising more than 3.6 degrees. To get there, he said the U.S. and other industrial nations have to begin permanent dramatic cuts in carbon dioxide pollution by 2015, with developing countries following suit within a decade.
Those efforts are racing against three tipping points he cited: Earth could be as close as six years away from the loss of Arctic summer sea ice, he said, and that has the potential of altering the climate in unforeseen ways. Other elements that could dramatically speed up climate change include the release of frozen methane from thawing permafrost in Siberia, and more and bigger wildfires worldwide.
The trouble is that no one knows when these things are coming, he said.
Holdren also addressed other topics during the interview:
_ The U.S. anti-ballistic missile program is not ready to work and shouldn't be used unless it is 100 percent effective. The system, which would be used to shoot down missiles from countries like North Korea or Iran "needs to be essentially perfect ... that's going to be hard to achieve."
_ Holdren said NASA needs some changes. He said the Bush administration's plan to return astronauts to the moon was underfunded so money was taken from science and aeronautics. Those areas, including climate change research, were "decimated," he said.
The administration will "rebalance NASA's programs so that we have in space exploration, a suitable mix of manned activities and robotic activities," Holdren said. Doing that "will only get under way in earnest when a new administrator is in place."
Holdren, who advises the president on such decisions, said he hopes Obama will pick a new NASA boss soon.
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On the Net:
Office of Science and Technology Policy: http://www.ostp.gov/ |
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