A Climate Skeptic With a Bully Pulpit in Virginia Finds an Ear in Congress
http://www.nytimes.com/2011/02/23/science/earth/23virginia.html?_r=1&hp
http://www.nytimes.com/2011/02/23/science/earth/23virginia.html?_r=1&hp
MESO-Rx
Anabolic Steroids
Climate Change
- Thread starter Michael Scally MD
- Start date
IG: NOAA clean on 'Climategate' e-mails
IG: NOAA clean on 'Climategate' e-mails - Dan Berman - POLITICO.com
The Commerce Department's inspector general has found little wrong in the so-called "Climategate" e-mails written by National Oceanic and Atmospheric Administration employees. http://www.oig.doc.gov/oig/reports/correspondence/2011.02.18_IG_to_%20Inhofe.pdf
To wit, the phrase “we found no evidence” appears at least six times in a new report from IG Todd Zinser, conducted at the request of climate skeptic Sen. Jim Inhofe (R-Okla.).
That includes "no evidence" that NOAA inappropriately manipulated data, "no evidence" to suggest that NOAA failed to adhere to its peer review procedures, and "no evidence" that NOAA violated the Information Quality Act.
NOAA chief Jane Lubchenco told the IG that she has personally read some of the NOAA-related e-mails and said she was "relieved because they were at odds with the way they were being publicly portrayed, and I thought that the ones I read [indicated] that NOAA scientists were exercising by and large good judgment and not doing things that were inappropriate" in their scientific work.
Out of the 1,073 e-mails from climate scientists around the world that were stolen from the Climate Research Unit at the University of East Anglia in late 2009, the IG found 10 that warranted further examination.
The IG also zeroed in on a February 2007 e-mail of an "inappropriate" image mocking Inhofe and other climate skeptics floating in the ocean near a melting ice can. NOAA chief Jane Lubchenco acknowledged that "it was in bad taste" and the agency says the creators of the picture have been "counseled by their respective supervisors."
Zinser did criticize the handling of four Freedom of Information Act requests to Susan Solomon regarding review comments on the Intergovernmental Panel on Climate Change, saying NOAA needs to revisit the inadequate responses and perhaps revise its FOIA policy.
Solomon, who is named only by title in the report, is a long-time NOAA scientist and was the co-chair of the IPCC's 2007 report. The IG said he was unable to reconcile "divergent accounts" of what advice Solomon was given when from her supervisor and a NOAA attorney regarding IPCC-related documents.
In a statement to POLITICO, Inhofe seizes on the FOIA response, saying it raises "serious questions about a refusal to share taxpayer-funded science with the public, potential data manipulation, and potential contracting fraud.”
NOAA did not respond to requests for comment.
IG: NOAA clean on 'Climategate' e-mails - Dan Berman - POLITICO.com
The Commerce Department's inspector general has found little wrong in the so-called "Climategate" e-mails written by National Oceanic and Atmospheric Administration employees. http://www.oig.doc.gov/oig/reports/correspondence/2011.02.18_IG_to_%20Inhofe.pdf
To wit, the phrase “we found no evidence” appears at least six times in a new report from IG Todd Zinser, conducted at the request of climate skeptic Sen. Jim Inhofe (R-Okla.).
That includes "no evidence" that NOAA inappropriately manipulated data, "no evidence" to suggest that NOAA failed to adhere to its peer review procedures, and "no evidence" that NOAA violated the Information Quality Act.
NOAA chief Jane Lubchenco told the IG that she has personally read some of the NOAA-related e-mails and said she was "relieved because they were at odds with the way they were being publicly portrayed, and I thought that the ones I read [indicated] that NOAA scientists were exercising by and large good judgment and not doing things that were inappropriate" in their scientific work.
Out of the 1,073 e-mails from climate scientists around the world that were stolen from the Climate Research Unit at the University of East Anglia in late 2009, the IG found 10 that warranted further examination.
The IG also zeroed in on a February 2007 e-mail of an "inappropriate" image mocking Inhofe and other climate skeptics floating in the ocean near a melting ice can. NOAA chief Jane Lubchenco acknowledged that "it was in bad taste" and the agency says the creators of the picture have been "counseled by their respective supervisors."
Zinser did criticize the handling of four Freedom of Information Act requests to Susan Solomon regarding review comments on the Intergovernmental Panel on Climate Change, saying NOAA needs to revisit the inadequate responses and perhaps revise its FOIA policy.
Solomon, who is named only by title in the report, is a long-time NOAA scientist and was the co-chair of the IPCC's 2007 report. The IG said he was unable to reconcile "divergent accounts" of what advice Solomon was given when from her supervisor and a NOAA attorney regarding IPCC-related documents.
In a statement to POLITICO, Inhofe seizes on the FOIA response, saying it raises "serious questions about a refusal to share taxpayer-funded science with the public, potential data manipulation, and potential contracting fraud.”
NOAA did not respond to requests for comment.
Hmmm....
Could it be the IG is just one of the political activists that have a nasty habit of hiding behind lies to push junk science? Let's let the truth decide: http://thegwpf.org/science-news/2515-climategate-new-light-on-delete-any-emails.html
After reading this piece, which includes actual emails and a critique that - gasp! - the IG did not seem too keen on interviewing anyone with a dissenting opinion - I think the answer is quite clear.
Once again for Global Warming alarmists it is one step forward, three steps back. You can't hide from the truth for long and just because the IG says the NOAA is clear does not make it so. As a matter of fact, it seems that believing in the opposite of anything the IG says leads one on a pathway to truth.
Could it be the IG is just one of the political activists that have a nasty habit of hiding behind lies to push junk science? Let's let the truth decide: http://thegwpf.org/science-news/2515-climategate-new-light-on-delete-any-emails.html
After reading this piece, which includes actual emails and a critique that - gasp! - the IG did not seem too keen on interviewing anyone with a dissenting opinion - I think the answer is quite clear.
Once again for Global Warming alarmists it is one step forward, three steps back. You can't hide from the truth for long and just because the IG says the NOAA is clear does not make it so. As a matter of fact, it seems that believing in the opposite of anything the IG says leads one on a pathway to truth.
Melting Ice Sheets Now Largest Contributor to Sea Level Rise
Melting ice sheets now largest contributor to sea level rise
Rignot E, Velicogna I, van den Broeke MR, Monaghan A, Lenaerts J. Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise. Geophys Res Lett 2011;38(5):L05503. http://www.agu.org/pubs/crossref/2011/2011GL046583.shtml
Ice sheet mass balance estimates have improved substantially in recent years using a variety of techniques, over different time periods, and at various levels of spatial detail. Considerable disparity remains between these estimates due to the inherent uncertainties of each method, the lack of detailed comparison between independent estimates, and the effect of temporal modulations in ice sheet surface mass balance. Here, we present a consistent record of mass balance for the Greenland and Antarctic ice sheets over the past two decades, validated by the comparison of two independent techniques over the last 8 years: one differencing perimeter loss from net accumulation, and one using a dense time series of time-variable gravity. We find excellent agreement between the two techniques for absolute mass loss and acceleration of mass loss. In 2006, the Greenland and Antarctic ice sheets experienced a combined mass loss of 475 ± 158 Gt/yr, equivalent to 1.3 ± 0.4 mm/yr sea level rise. Notably, the acceleration in ice sheet loss over the last 18 years was 21.9 ± 1 Gt/yr2 for Greenland and 14.5 ± 2 Gt/yr2 for Antarctica, for a combined total of 36.3 ± 2 Gt/yr2. This acceleration is 3 times larger than for mountain glaciers and ice caps (12 ± 6 Gt/yr2). If this trend continues, ice sheets will be the dominant contributor to sea level rise in the 21st century.
Melting ice sheets now largest contributor to sea level rise
Rignot E, Velicogna I, van den Broeke MR, Monaghan A, Lenaerts J. Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise. Geophys Res Lett 2011;38(5):L05503. http://www.agu.org/pubs/crossref/2011/2011GL046583.shtml
Ice sheet mass balance estimates have improved substantially in recent years using a variety of techniques, over different time periods, and at various levels of spatial detail. Considerable disparity remains between these estimates due to the inherent uncertainties of each method, the lack of detailed comparison between independent estimates, and the effect of temporal modulations in ice sheet surface mass balance. Here, we present a consistent record of mass balance for the Greenland and Antarctic ice sheets over the past two decades, validated by the comparison of two independent techniques over the last 8 years: one differencing perimeter loss from net accumulation, and one using a dense time series of time-variable gravity. We find excellent agreement between the two techniques for absolute mass loss and acceleration of mass loss. In 2006, the Greenland and Antarctic ice sheets experienced a combined mass loss of 475 ± 158 Gt/yr, equivalent to 1.3 ± 0.4 mm/yr sea level rise. Notably, the acceleration in ice sheet loss over the last 18 years was 21.9 ± 1 Gt/yr2 for Greenland and 14.5 ± 2 Gt/yr2 for Antarctica, for a combined total of 36.3 ± 2 Gt/yr2. This acceleration is 3 times larger than for mountain glaciers and ice caps (12 ± 6 Gt/yr2). If this trend continues, ice sheets will be the dominant contributor to sea level rise in the 21st century.
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Ice in Motion
As frozen lands disintegrate, researchers rush to catch the collapse
http://www.sciencenews.org/view/feature/id/70902/title/Ice_in_Motion
As frozen lands disintegrate, researchers rush to catch the collapse
http://www.sciencenews.org/view/feature/id/70902/title/Ice_in_Motion
My experts are smarter than your experts
The UC is the University of California. Youir clowns couldnt have passed the entrance exam.
How Will Our Cities Cope with Climate Change? - UCTV - University of California Television
The UC is the University of California. Youir clowns couldnt have passed the entrance exam.
How Will Our Cities Cope with Climate Change? - UCTV - University of California Television
My experts are smarter than your experts
The UC is the University of California. Youir clowns couldnt have passed the entrance exam.
How Will Our Cities Cope with Climate Change? - UCTV - University of California Television
Sorry but anything with the word California in it does not impress me at all. It actually is a signal that what I am about to hear is a total bucket of BS. The state is bankrupt, companies are fleeing, talent is fleeing - it is a modern version of Atlas Shrugged.
Increasing greenhouse gas concentrations are expected to amplify the variability of summer temperatures in Europe. Along with mean warming, enhanced variability results in more frequent, persistent and intense heat waves. Consistent with these expectations, Europe has experienced devastating heat waves in recent years. The exceptional summer of 2003 caused around 70,000 heat related deaths mainly in western and central Europe. In summer 2010 many cities in eastern Europe recorded extremely high values of daytime (e.g. Moscow: 38.2ºC), nighttime (e.g. Kiev: 25ºC) and daily mean (e.g. Helsinki: 26.1ºC) temperatures. Preliminary estimates for Russia referred a death toll of 55,000, an annual crop failure of ~25%, more than 1 million ha of burned areas and ~US$15 billion (~1% GDP) of total economic loss. During the same period, parts of eastern Asia also experienced extremely warm temperatures and Pakistan was hit by devastating monsoon floods.
Barriopedro D, Fischer EM, Luterbacher Jr, Trigo RM, Garcia-Herrera R. The Hot Summer of 2010: Redrawing the Temperature Record Map of Europe. Science. The Hot Summer of 2010: Redrawing the Temperature Record Map of Europe
The summer of 2010 was exceptionally warm in eastern Europe and large parts of Russia. We provide evidence that the anomalous 2010 warmth that caused adverse impacts exceeded the amplitude and spatial extent of the previous hottest summer of 2003. 'Mega-heatwaves' such as the 2003 and 2010 events broke the 500-yr long seasonal temperature records over approximately 50% of Europe. According to regional multi-model experiments, the probability of a summer experiencing 'mega heat waves' will increase by a factor of 5 to 10 within the next 40 years. However, the magnitude of the 2010 event was so extreme that despite this increase, the occurrence of an analogue over the same region remains fairly unlikely until the second half of the 21st century.
Barriopedro D, Fischer EM, Luterbacher Jr, Trigo RM, Garcia-Herrera R. The Hot Summer of 2010: Redrawing the Temperature Record Map of Europe. Science. The Hot Summer of 2010: Redrawing the Temperature Record Map of Europe
The summer of 2010 was exceptionally warm in eastern Europe and large parts of Russia. We provide evidence that the anomalous 2010 warmth that caused adverse impacts exceeded the amplitude and spatial extent of the previous hottest summer of 2003. 'Mega-heatwaves' such as the 2003 and 2010 events broke the 500-yr long seasonal temperature records over approximately 50% of Europe. According to regional multi-model experiments, the probability of a summer experiencing 'mega heat waves' will increase by a factor of 5 to 10 within the next 40 years. However, the magnitude of the 2010 event was so extreme that despite this increase, the occurrence of an analogue over the same region remains fairly unlikely until the second half of the 21st century.
Multitude of Species Face Climate Threat
http://www.nytimes.com/2011/04/05/science/earth/05climate.html
April 4, 2011
By CARL ZIMMER
Over the past 540 million years, life on Earth has passed through five great mass extinctions. In each of those catastrophes, an estimated 75 percent or more of all species disappeared in a few million years or less.
For decades, scientists have warned that humans may be ushering in a sixth mass extinction, and recently a group of scientists at the University of California, Berkeley, tested the hypothesis. They applied new statistical methods to a new generation of fossil databases. As they reported last month in the journal Nature, the current rate of extinctions is far above normal. If endangered species continue to disappear, we will indeed experience a sixth extinction, over just the next few centuries or millennia.
The Berkeley scientists warn that their new study may actually grossly underestimate how many species could disappear. So far, humans have pushed species toward extinctions through means like hunting, overfishing and deforestation. Global warming, on the other hand, is only starting to make itself felt in the natural world. Many scientists expect that as the planet’s temperature rises, global warming could add even more devastation. “The current rate and magnitude of climate change are faster and more severe than many species have experienced in their evolutionary history,” said Anthony Barnosky, the lead author of the Nature study.
But equally as strong as the conclusion that global warming can push extinctions is the difficulty in linking the fate of any single species to climate. Policy makers would like to get a better idea of exactly what to expect — how many species will risk extinction, and which ones are most likely to wink out of existence. But scientists who study the impact of global warming on biodiversity are pushing back against the pressure for detailed forecasts. While it’s clear that global warming’s impact could potentially be huge, scientists are warning that it’s still impossible to provide fine-grained predictions.
“We need to stand firm about the real complexity of biological systems and not let policy makers push us into simplistic answers,” said Camille Parmesan, a biologist at the University of Texas. She and others studying climate’s effects on biodiversity are calling for conservation measures that don’t rely on impossible precision.
Dr. Parmesan herself has gathered some of the most compelling evidence that global warming is already leaving its mark on nature. In 2003, she and Gary Yohe, an economist at Wesleyan University, analyzed records of the geographical ranges of more than 1,700 species of plants and animals. They found that their ranges were moving, on average, 3.8 miles per decade toward the poles. Animals and plants were also moving up mountain slopes.
These were the sorts of changes you’d expect from global warming. The warmer edges of a range might become too hot for a species to survive, while the cooler edge becomes more suitable. What’s more, only worldwide climate change could explain the entire pattern. “Because it’s happening consistently on a global scale, we can link it to greenhouse gases changes,” Dr. Parmesan said.
Dr. Parmesan and her colleagues have continued to expand their database since then. But other researchers have been moving in the opposite direction, seeking to attribute changes in individual species to climate change. Last year, for example, Michael Kearney of the University of Melbourne and his colleagues published a study on the common brown butterfly of Australia. From 1941 to 2005, adult butterflies had been emerging from their pupae 1.5 days earlier per decade around Melbourne.
To see if the brown butterfly is actually responding to climate change, Dr. Kearney and his colleagues first analyzed historical temperature records in Melbourne. Temperatures have gradually risen over the past 60 years. Computer models indicate that natural climate cycles can explain only a small part of the change.
The scientists then observed how temperature affects how brown butterflies develop. The warmer the temperature, the faster the butterflies emerged from their pupae. Dr. Kearney and his colleagues used those results to build a mathematical model to predict how long the butterflies would develop at any given temperature. They determined that Melbourne’s local warming should have led to the butterflies emerging 1.5 days earlier per decade — exactly what the butterflies are, in fact, doing.
In the journal Nature Climate Change, Dr. Parmesan and her colleagues argue that trying to attribute specific biological changes to global warming is the wrong way to go. While the global fingerprint of climate change may be clear, the picture can get blurry in individual species. “When you go to the local level, the outcome of climate change on one particular species is not dependent just on what climate change is doing,” said Dr. Parmesan.
In Europe, for example, the map butterfly has expanded its range at both its northern and its southern edge. Global warming probably has something to do with its northern expansion. But the butterflies are also benefiting from the mowing of roadsides, which allows more nettle plants to grow. Because map butterflies feed on nettles, they’re able to survive across a broader range of Europe.
A number of experts applaud the commentary from Dr. Parmesan and her colleagues. “I think they really hit the nail on the head,” said Richard Pearson, the director of biodiversity informatics research at the American Museum of Natural History. “Biologists shouldn’t get drawn heavily into the attribution debate.”
But some researchers counter that such studies can be worthwhile cases where global warming’s impact on an individual species is clear. “The fact that the task may simply be too challenging in most cases does not mean that it will be impossible or a waste of effort in some particular cases,” said Dáithí Stone, a climate scientist at the University of Cape Town in South Africa.
Tracking the effects of climate change on species today can help show how nature may respond to it in decades to come. And many scientists think that the future looks grim. As temperatures rise, many species may not be able to shift their ranges to stay in a comfortable environment. Instead, their ranges may shrink, pushing them toward extinction.
Over the past decade, Dr. Pearson and other researchers have developed models to predict these future range shifts. They typically calculate the “climate envelope” in which species live today, and then use global warming projections to find where their climate envelopes will be in the future.
These models first came to prominence in 2004, when an international team of scientists published a study of more than a thousand species. They estimated that 15 percent to 37 percent of all species could become “committed to extinction” by 2050, thanks to climate change.
“It was a big splash for the field,” recalled Dr. Pearson. But in his new book, “Driven to Extinction,” Dr. Pearson recounts how he cringed to see the research boiled down to simple, stark headlines that said a million species were doomed.
“Biodiversity is under severe threat from climate change, but we need to be careful that we don’t give a false impression of what our confidence is,” said Dr. Pearson. “We have to give a nuanced sense of what we do know and what we can say with confidence.”
Seven years after the million-species headlines, Dr. Pearson says that extinction models still have a long way to go. “We’ve made some incremental improvements, but I don’t think they’re hugely better,” he said.
“It’s been a very powerful tool, but my concern is that it’s very weak on biology,” said Georgina Mace of Imperial College London. In the latest issue of Science, she and her colleagues use the fossil record to demonstrate how seemingly similar species can respond in different ways to climate change.
When the planet warmed at the end of the ice age 11,000 years ago, for example, the change was too much for Irish elk, which became extinct. Moose, on the other hand, have survived. Some moose populations stayed put; other populations shifted to more suitable places.
Dr. Mace and her colleagues call for new models that can assess the sensitivity of species to climate, as well as their ability to adapt. In some cases, that adaptation may be evolution. Species may become better able to tolerate warmer temperatures or a change in rainfall. In other cases, animals may adapt by changing their behavior.
Polar bears, for example, are having a harder time hunting seals because of melting sea ice. “They don’t say, we can’t eat seals anymore, so we’re just going to starve,” Dr. Pearson said. Instead, some bears are getting more food on land, raiding goose nests for their eggs.
While this switch may slow the decline of polar bears, it’s not great news for the geese. Dr. Pearson notes that all the influences that species have on one another will also determine how climate change affects them. “Predicting how communities will respond is really tricky,” he said.
Dr. Mace argues that a fuller accounting of how species cope with climate could let scientists revise their estimate for how many species could become extinct. “I think it could be a lot worse for some groups of species, and not as bad for others,” she said.
Humans add even more complexity to the forecast. Cities and farms now block the path for many species that might otherwise be able to spread to more suitable habitats, for example. Dr. Parmesan thinks much more research should go into the interactions of global warming and other human impacts. Scientists in Australia have found that coral reefs are more resilient against global warming, for example, if they’re protected from overfishing. The warming oceans stimulate the growth of deadly algae on the reefs. But grazing fish can keep the algae in check.
Such research will become the basis for decisions about which species to help, and how. Dr. Mace believes that some especially vulnerable species may need to be moved to new habitats in order to survive. Dr. Parmesan thinks that reducing other pressures, like overfishing, will make species more resilient to climate change. “We know that climate change wouldn’t be such a big problem if systems weren’t already stressed,” Dr. Parmesan said. “We really need to focus on reducing these other stressors.”
Dr. Pearson, on the other hand, argues for setting aside more land in parks and reserves. More space will help keep species ranges large even if those ranges shift.
“We need to give nature the opportunity to respond,” he said.
http://www.nytimes.com/2011/04/05/science/earth/05climate.html
April 4, 2011
By CARL ZIMMER
Over the past 540 million years, life on Earth has passed through five great mass extinctions. In each of those catastrophes, an estimated 75 percent or more of all species disappeared in a few million years or less.
For decades, scientists have warned that humans may be ushering in a sixth mass extinction, and recently a group of scientists at the University of California, Berkeley, tested the hypothesis. They applied new statistical methods to a new generation of fossil databases. As they reported last month in the journal Nature, the current rate of extinctions is far above normal. If endangered species continue to disappear, we will indeed experience a sixth extinction, over just the next few centuries or millennia.
The Berkeley scientists warn that their new study may actually grossly underestimate how many species could disappear. So far, humans have pushed species toward extinctions through means like hunting, overfishing and deforestation. Global warming, on the other hand, is only starting to make itself felt in the natural world. Many scientists expect that as the planet’s temperature rises, global warming could add even more devastation. “The current rate and magnitude of climate change are faster and more severe than many species have experienced in their evolutionary history,” said Anthony Barnosky, the lead author of the Nature study.
But equally as strong as the conclusion that global warming can push extinctions is the difficulty in linking the fate of any single species to climate. Policy makers would like to get a better idea of exactly what to expect — how many species will risk extinction, and which ones are most likely to wink out of existence. But scientists who study the impact of global warming on biodiversity are pushing back against the pressure for detailed forecasts. While it’s clear that global warming’s impact could potentially be huge, scientists are warning that it’s still impossible to provide fine-grained predictions.
“We need to stand firm about the real complexity of biological systems and not let policy makers push us into simplistic answers,” said Camille Parmesan, a biologist at the University of Texas. She and others studying climate’s effects on biodiversity are calling for conservation measures that don’t rely on impossible precision.
Dr. Parmesan herself has gathered some of the most compelling evidence that global warming is already leaving its mark on nature. In 2003, she and Gary Yohe, an economist at Wesleyan University, analyzed records of the geographical ranges of more than 1,700 species of plants and animals. They found that their ranges were moving, on average, 3.8 miles per decade toward the poles. Animals and plants were also moving up mountain slopes.
These were the sorts of changes you’d expect from global warming. The warmer edges of a range might become too hot for a species to survive, while the cooler edge becomes more suitable. What’s more, only worldwide climate change could explain the entire pattern. “Because it’s happening consistently on a global scale, we can link it to greenhouse gases changes,” Dr. Parmesan said.
Dr. Parmesan and her colleagues have continued to expand their database since then. But other researchers have been moving in the opposite direction, seeking to attribute changes in individual species to climate change. Last year, for example, Michael Kearney of the University of Melbourne and his colleagues published a study on the common brown butterfly of Australia. From 1941 to 2005, adult butterflies had been emerging from their pupae 1.5 days earlier per decade around Melbourne.
To see if the brown butterfly is actually responding to climate change, Dr. Kearney and his colleagues first analyzed historical temperature records in Melbourne. Temperatures have gradually risen over the past 60 years. Computer models indicate that natural climate cycles can explain only a small part of the change.
The scientists then observed how temperature affects how brown butterflies develop. The warmer the temperature, the faster the butterflies emerged from their pupae. Dr. Kearney and his colleagues used those results to build a mathematical model to predict how long the butterflies would develop at any given temperature. They determined that Melbourne’s local warming should have led to the butterflies emerging 1.5 days earlier per decade — exactly what the butterflies are, in fact, doing.
In the journal Nature Climate Change, Dr. Parmesan and her colleagues argue that trying to attribute specific biological changes to global warming is the wrong way to go. While the global fingerprint of climate change may be clear, the picture can get blurry in individual species. “When you go to the local level, the outcome of climate change on one particular species is not dependent just on what climate change is doing,” said Dr. Parmesan.
In Europe, for example, the map butterfly has expanded its range at both its northern and its southern edge. Global warming probably has something to do with its northern expansion. But the butterflies are also benefiting from the mowing of roadsides, which allows more nettle plants to grow. Because map butterflies feed on nettles, they’re able to survive across a broader range of Europe.
A number of experts applaud the commentary from Dr. Parmesan and her colleagues. “I think they really hit the nail on the head,” said Richard Pearson, the director of biodiversity informatics research at the American Museum of Natural History. “Biologists shouldn’t get drawn heavily into the attribution debate.”
But some researchers counter that such studies can be worthwhile cases where global warming’s impact on an individual species is clear. “The fact that the task may simply be too challenging in most cases does not mean that it will be impossible or a waste of effort in some particular cases,” said Dáithí Stone, a climate scientist at the University of Cape Town in South Africa.
Tracking the effects of climate change on species today can help show how nature may respond to it in decades to come. And many scientists think that the future looks grim. As temperatures rise, many species may not be able to shift their ranges to stay in a comfortable environment. Instead, their ranges may shrink, pushing them toward extinction.
Over the past decade, Dr. Pearson and other researchers have developed models to predict these future range shifts. They typically calculate the “climate envelope” in which species live today, and then use global warming projections to find where their climate envelopes will be in the future.
These models first came to prominence in 2004, when an international team of scientists published a study of more than a thousand species. They estimated that 15 percent to 37 percent of all species could become “committed to extinction” by 2050, thanks to climate change.
“It was a big splash for the field,” recalled Dr. Pearson. But in his new book, “Driven to Extinction,” Dr. Pearson recounts how he cringed to see the research boiled down to simple, stark headlines that said a million species were doomed.
“Biodiversity is under severe threat from climate change, but we need to be careful that we don’t give a false impression of what our confidence is,” said Dr. Pearson. “We have to give a nuanced sense of what we do know and what we can say with confidence.”
Seven years after the million-species headlines, Dr. Pearson says that extinction models still have a long way to go. “We’ve made some incremental improvements, but I don’t think they’re hugely better,” he said.
“It’s been a very powerful tool, but my concern is that it’s very weak on biology,” said Georgina Mace of Imperial College London. In the latest issue of Science, she and her colleagues use the fossil record to demonstrate how seemingly similar species can respond in different ways to climate change.
When the planet warmed at the end of the ice age 11,000 years ago, for example, the change was too much for Irish elk, which became extinct. Moose, on the other hand, have survived. Some moose populations stayed put; other populations shifted to more suitable places.
Dr. Mace and her colleagues call for new models that can assess the sensitivity of species to climate, as well as their ability to adapt. In some cases, that adaptation may be evolution. Species may become better able to tolerate warmer temperatures or a change in rainfall. In other cases, animals may adapt by changing their behavior.
Polar bears, for example, are having a harder time hunting seals because of melting sea ice. “They don’t say, we can’t eat seals anymore, so we’re just going to starve,” Dr. Pearson said. Instead, some bears are getting more food on land, raiding goose nests for their eggs.
While this switch may slow the decline of polar bears, it’s not great news for the geese. Dr. Pearson notes that all the influences that species have on one another will also determine how climate change affects them. “Predicting how communities will respond is really tricky,” he said.
Dr. Mace argues that a fuller accounting of how species cope with climate could let scientists revise their estimate for how many species could become extinct. “I think it could be a lot worse for some groups of species, and not as bad for others,” she said.
Humans add even more complexity to the forecast. Cities and farms now block the path for many species that might otherwise be able to spread to more suitable habitats, for example. Dr. Parmesan thinks much more research should go into the interactions of global warming and other human impacts. Scientists in Australia have found that coral reefs are more resilient against global warming, for example, if they’re protected from overfishing. The warming oceans stimulate the growth of deadly algae on the reefs. But grazing fish can keep the algae in check.
Such research will become the basis for decisions about which species to help, and how. Dr. Mace believes that some especially vulnerable species may need to be moved to new habitats in order to survive. Dr. Parmesan thinks that reducing other pressures, like overfishing, will make species more resilient to climate change. “We know that climate change wouldn’t be such a big problem if systems weren’t already stressed,” Dr. Parmesan said. “We really need to focus on reducing these other stressors.”
Dr. Pearson, on the other hand, argues for setting aside more land in parks and reserves. More space will help keep species ranges large even if those ranges shift.
“We need to give nature the opportunity to respond,” he said.
Critics' review unexpectedly supports scientific consensus on global warming
A UC Berkeley team's preliminary findings in a review of temperature data confirm global warming studies.
Global warming: Critics' review unexpectedly supports scientific consensus on climate change - latimes.com
By Margot Roosevelt, Los Angeles Times
April 4, 2011
A team of UC Berkeley physicists and statisticians that set out to challenge the scientific consensus on global warming is finding that its data-crunching effort is producing results nearly identical to those underlying the prevailing view.
The Berkeley Earth Surface Temperature project was launched by physics professor Richard Muller, a longtime critic of government-led climate studies, to address what he called "the legitimate concerns" of skeptics who believe that global warming is exaggerated.
But Muller unexpectedly told a congressional hearing last week that the work of the three principal groups that have analyzed the temperature trends underlying climate science is "excellent.... We see a global warming trend that is very similar to that previously reported by the other groups."
The hearing was called by GOP leaders of the House Science & Technology committee, who have expressed doubts about the integrity of climate science. It was one of several inquiries in recent weeks as the Environmental Protection Agency's efforts to curb planet-heating emissions from industrial plants and motor vehicles have come under strenuous attack in Congress.
Muller said his group was surprised by its findings, but he cautioned that the initial assessment is based on only 2% of the 1.6 billion measurements that will eventually be examined.
The Berkeley project's biggest private backer, at $150,000, is the Charles G. Koch Charitable Foundation. Oil billionaires Charles and David Koch are the nation's most prominent funders of efforts to prevent curbs on the burning of fossil fuels, the largest contributor to planet-warming greenhouse gases.
The $620,000 project is also partly funded by the federal Lawrence Berkeley National Laboratory, where Muller is a senior scientist. Muller said the Koch foundation and other contributors will have no influence over the results, which he plans to submit to peer-reviewed scientific journals.
Ken Caldeira, an atmospheric scientist at the Carnegie Institution for Science, which contributed some funding to the Berkeley effort, said Muller's statement to Congress was "honorable" in recognizing that "previous temperature reconstructions basically got it right…. Willingness to revise views in the face of empirical data is the hallmark of the good scientific process."
But conservative critics who had expected Muller's group to demonstrate a bias among climate scientists reacted with disappointment.
Anthony Watts, a former TV weatherman who runs the skeptic blog WattsUpWithThat.com, wrote that the Berkeley group is releasing results that are not "fully working and debugged yet.... But, post normal science political theater is like that."
Over the years, Muller has praised Watts' efforts to show that weather station data in official studies are untrustworthy because of the urban heat island effect, which boosts temperature readings in areas that have been encroached on by cities and suburbs.
But leading climatologists said the previous studies accounted for the effect, and the Berkeley analysis is confirming that, Muller acknowledged. "Did such poor station quality exaggerate the estimates of global warming?" he asked in his written testimony. "We've studied this issue, and our preliminary answer is no."
Temperature data are gathered from tens of thousands of weather stations around the globe, many of which have incomplete records. Over the last two decades, three independent groups have used different combinations of stations and varying statistical methods and yet arrived at nearly identical conclusions: The planet's surface, on average, has warmed about 0.75 degrees centigrade (1.4 degrees Fahrenheit) since the beginning of the 20th century.
Temperature data were the focus of the so-called 2009 Climategate controversy, in which opponents of greenhouse gas regulation alleged that leaked emails from a British climate laboratory showed manipulation of weather station records. Five U.S. and British government and university investigations have refuted the charges.
"For those who wish to discredit the science, this [temperature] record is the holy grail," said Peter Thorne, a leading expert at the National Oceanic and Atmospheric Administration's National Climatic Data Center in Asheville, N.C. "They figure if they can discredit this, then society would have significant doubts about all of climate science."
Thorne said scientists who contributed to the three main studies — by NOAA, NASA and Britain's Met Office — welcome new peer-reviewed research. But he said the Berkeley team had been "seriously compromised" by publicizing its work before publishing any vetted papers.
On the project's website, in a public lecture and in statements to the media, Muller had portrayed the Berkeley effort as rectifying the "biases" of previous studies, a task he compared with "Hercules cleaning out the Augean stables." He said his study would be "more precise," analyzing data from 39,000 stations — more than any other study — and offering "transparent," rather than "homogenized" data.
Kevin Trenberth, who heads the Climate Analysis Section of the National Center for Atmospheric Research, a university consortium, said he was "highly skeptical of the hype and claims" surrounding the Berkeley effort. "The team has some good people," he said, "but not the expertise required in certain areas, and purely statistical approaches are naive."
The project team includes UC Berkeley statistician David Brillinger and UC Berkeley physicists Don Groom, Robert Jacobsen, Saul Perlmutter, Arthur Rosenfeld and Jonathan Wurtele. The group's atmospheric scientist is Judith Curry, chairwoman of the School of Earth and Atmospheric Science at Georgia Tech, who has suggested that temperature data were "airbrushed" by other scientists.
One full-time staffer, Richard Rohde, a who recently earned a doctorate in statistics, is doing most of the work, Muller said.
Although in his testimony Muller praised the "integrity" of previous studies, he said estimates of human-caused warming need to be "improved." And despite his preliminary praise for earlier studies, he said further data-crunching "could bring our current agreement into disagreement."
Other scientists noted that temperature is only one factor in climate change. "Even if the thermometer had never been invented, the evidence is there from deep ocean changes, from receding glaciers, from rising sea levels and receding sea ice and spring snow cover," Thorne said.
"All the physical indicators are consistent with a warming world. There is no doubt the trend of temperature is upwards since the early 20th century. And that trend is accelerating."
Testimony: http://berkeleyearth.org/Resources/Muller_Testimony_31_March_2011
A UC Berkeley team's preliminary findings in a review of temperature data confirm global warming studies.
Global warming: Critics' review unexpectedly supports scientific consensus on climate change - latimes.com
By Margot Roosevelt, Los Angeles Times
April 4, 2011
A team of UC Berkeley physicists and statisticians that set out to challenge the scientific consensus on global warming is finding that its data-crunching effort is producing results nearly identical to those underlying the prevailing view.
The Berkeley Earth Surface Temperature project was launched by physics professor Richard Muller, a longtime critic of government-led climate studies, to address what he called "the legitimate concerns" of skeptics who believe that global warming is exaggerated.
But Muller unexpectedly told a congressional hearing last week that the work of the three principal groups that have analyzed the temperature trends underlying climate science is "excellent.... We see a global warming trend that is very similar to that previously reported by the other groups."
The hearing was called by GOP leaders of the House Science & Technology committee, who have expressed doubts about the integrity of climate science. It was one of several inquiries in recent weeks as the Environmental Protection Agency's efforts to curb planet-heating emissions from industrial plants and motor vehicles have come under strenuous attack in Congress.
Muller said his group was surprised by its findings, but he cautioned that the initial assessment is based on only 2% of the 1.6 billion measurements that will eventually be examined.
The Berkeley project's biggest private backer, at $150,000, is the Charles G. Koch Charitable Foundation. Oil billionaires Charles and David Koch are the nation's most prominent funders of efforts to prevent curbs on the burning of fossil fuels, the largest contributor to planet-warming greenhouse gases.
The $620,000 project is also partly funded by the federal Lawrence Berkeley National Laboratory, where Muller is a senior scientist. Muller said the Koch foundation and other contributors will have no influence over the results, which he plans to submit to peer-reviewed scientific journals.
Ken Caldeira, an atmospheric scientist at the Carnegie Institution for Science, which contributed some funding to the Berkeley effort, said Muller's statement to Congress was "honorable" in recognizing that "previous temperature reconstructions basically got it right…. Willingness to revise views in the face of empirical data is the hallmark of the good scientific process."
But conservative critics who had expected Muller's group to demonstrate a bias among climate scientists reacted with disappointment.
Anthony Watts, a former TV weatherman who runs the skeptic blog WattsUpWithThat.com, wrote that the Berkeley group is releasing results that are not "fully working and debugged yet.... But, post normal science political theater is like that."
Over the years, Muller has praised Watts' efforts to show that weather station data in official studies are untrustworthy because of the urban heat island effect, which boosts temperature readings in areas that have been encroached on by cities and suburbs.
But leading climatologists said the previous studies accounted for the effect, and the Berkeley analysis is confirming that, Muller acknowledged. "Did such poor station quality exaggerate the estimates of global warming?" he asked in his written testimony. "We've studied this issue, and our preliminary answer is no."
Temperature data are gathered from tens of thousands of weather stations around the globe, many of which have incomplete records. Over the last two decades, three independent groups have used different combinations of stations and varying statistical methods and yet arrived at nearly identical conclusions: The planet's surface, on average, has warmed about 0.75 degrees centigrade (1.4 degrees Fahrenheit) since the beginning of the 20th century.
Temperature data were the focus of the so-called 2009 Climategate controversy, in which opponents of greenhouse gas regulation alleged that leaked emails from a British climate laboratory showed manipulation of weather station records. Five U.S. and British government and university investigations have refuted the charges.
"For those who wish to discredit the science, this [temperature] record is the holy grail," said Peter Thorne, a leading expert at the National Oceanic and Atmospheric Administration's National Climatic Data Center in Asheville, N.C. "They figure if they can discredit this, then society would have significant doubts about all of climate science."
Thorne said scientists who contributed to the three main studies — by NOAA, NASA and Britain's Met Office — welcome new peer-reviewed research. But he said the Berkeley team had been "seriously compromised" by publicizing its work before publishing any vetted papers.
On the project's website, in a public lecture and in statements to the media, Muller had portrayed the Berkeley effort as rectifying the "biases" of previous studies, a task he compared with "Hercules cleaning out the Augean stables." He said his study would be "more precise," analyzing data from 39,000 stations — more than any other study — and offering "transparent," rather than "homogenized" data.
Kevin Trenberth, who heads the Climate Analysis Section of the National Center for Atmospheric Research, a university consortium, said he was "highly skeptical of the hype and claims" surrounding the Berkeley effort. "The team has some good people," he said, "but not the expertise required in certain areas, and purely statistical approaches are naive."
The project team includes UC Berkeley statistician David Brillinger and UC Berkeley physicists Don Groom, Robert Jacobsen, Saul Perlmutter, Arthur Rosenfeld and Jonathan Wurtele. The group's atmospheric scientist is Judith Curry, chairwoman of the School of Earth and Atmospheric Science at Georgia Tech, who has suggested that temperature data were "airbrushed" by other scientists.
One full-time staffer, Richard Rohde, a who recently earned a doctorate in statistics, is doing most of the work, Muller said.
Although in his testimony Muller praised the "integrity" of previous studies, he said estimates of human-caused warming need to be "improved." And despite his preliminary praise for earlier studies, he said further data-crunching "could bring our current agreement into disagreement."
Other scientists noted that temperature is only one factor in climate change. "Even if the thermometer had never been invented, the evidence is there from deep ocean changes, from receding glaciers, from rising sea levels and receding sea ice and spring snow cover," Thorne said.
"All the physical indicators are consistent with a warming world. There is no doubt the trend of temperature is upwards since the early 20th century. And that trend is accelerating."
Testimony: http://berkeleyearth.org/Resources/Muller_Testimony_31_March_2011
http://climaterealists.com/index.php?id=7497&linkbox=true&position=19
This is starting to sound like the nuclear alarmists vis-a-vis Japan. However, saner minds are already starting to provide sound mathematical arguments based on - oh my God!!!! - logic.
Methinks the media is once again jumping the gun and environuts are jumping up and down like coked out dancers at an all night rave over what is basically a statement that bad data was used properly as bad data.
Jeez.
This is starting to sound like the nuclear alarmists vis-a-vis Japan. However, saner minds are already starting to provide sound mathematical arguments based on - oh my God!!!! - logic.
Methinks the media is once again jumping the gun and environuts are jumping up and down like coked out dancers at an all night rave over what is basically a statement that bad data was used properly as bad data.
Jeez.
As global warming from unlimited fossil fuel burning accelerates, the Arctic is being radically transformed. This winter saw large regions of Canada and Greenland about 10°C (about 15-20°F) above the historical average. Temperatures in eastern Canada in the dead of winter were a staggering 21°C (37.8°F) above average. In a summary of how global climate change is becoming observable to people in their daily lives, NASA scientist James Hansen was forced to redraw his global map with hot pink (see attachment).
Attachments
http://www.nationalreview.com/planet-gore/264025/delglobal-warmingdel-climate-change-strikes-entire-planet-greg-pollowitz
Global temperature still headed down- UAH: negative territory
The global temperature has fallen .653°C (from +0.554 in March 2010 to -0.099 in March 2011) in just one year. That’s a magnitude nearly equivalent to the agreed upon global warming signal agreed upon by the IPCC. It is quite a sharp drop
Global temperature still headed down- UAH: negative territory
The global temperature has fallen .653°C (from +0.554 in March 2010 to -0.099 in March 2011) in just one year. That’s a magnitude nearly equivalent to the agreed upon global warming signal agreed upon by the IPCC. It is quite a sharp drop
How about using an average comparison(s), rather than two points in time?
Climate change - A study dealing with variations in climate on many different time scales from decades to millions of years, and the possible causes of such variations. http://nsidc.org/arcticmet/glossary/climate_change.html
Climate change - Climate change refers to a statistically significant variation in either the mean state of the climate or in its variability, persisting for an extended period (typically decades or longer). http://www.grida.no/publications/other/ipcc_tar/?src=/climate/ipcc_tar/wg1/
Last edited:
Melting Antarctic Ice Causing Penguins to Starve
Melting Antarctic Ice Causing Penguins to Starve - ScienceNOW
Sara Reardon
11 April 2011
Every year since 1979, marine biologist Wayne Trivelpiece and his wife, Susan, both of the National Oceanic and Atmospheric Association's Antarctic Ecosystem Research Division in San Diego, California, have braved frigid temperatures and wind speeds that average 40 kilometers per hour to track the feeding, breeding, and migrating of chinstrap and Adelie penguins. During this time, populations they studied on the West Antarctic Peninsula and in the nearby Scotia Sea have declined drastically, and a few have gone extinct, victims of a warming planet that deprives them of their sea ice habitat. Now, in a compilation of over 30 years of data collected from numerous bases around Antarctica, the researchers conclude that the penguins are not only running out of room but also starving.
In 1992, the pair published a paper with ecologist William Fraser, now president of the privately owned Polar Ocean Research Group based in Sheridan, Montana, proposing what they deemed the "habitat hypothesis," the idea that melting sea ice along the Antarctic coast was harming penguins. The average temperature in the region of the Scotia Sea, one of the most rapidly warming places on the planet, has increased by 5?C to 6?C over the past 50 years, drastically reducing the amount of sea ice present and the length of time that the ice exists. The researchers proposed that losing their habitat was what was killing Adelie penguins, which need ice to survive. By contrast, the numbers of chinstrap penguins, which avoid sea ice as much as possible, were booming.
But by incorporating data from land-based stations and tourist ships that moonlight as penguin-counting research vessels, the researchers have expanded their data set and reexamined it. In a paper published today in the Proceedings of the National Academy of Sciences, the Trivelpieces and their colleagues propose that a decrease in krill—shrimplike crustaceans that are a staple food for penguins—is to blame for the decline in Adelie penguins and chinstrap penguins, whose populations are now shrinking by 2.9% and 4.3%, respectively, each year. As it turns out, krill larvae are as dependent on sea ice as Adelie penguins are, feeding on algae that grow on the underside of ice packs; krill numbers have dropped by 80% since 1981. Independent of whether they like ice, Adelie and chinstrap penguins like to eat krill.
Back in the 1980s, Wayne Trivelpiece says, when researchers first started noticing a rapid decline in penguin populations, it was unclear what the reason was. To check their hunch that the cause was a food shortage, they began forcing penguin parents returning from the sea to vomit by inverting them over a bucket and pushing on their stomachs. Chinstrap penguins, they and other researchers found, eat krill exclusively; Adelie penguins are dependent on it as well. Continuing research through the 1990s showed that the size of the krill was uniform, suggesting that only a few krill populations were maturing over the years and were available for penguins to eat. Satellite data showed that krill numbers fell in areas where sea ice dwindled. "As aggravating as it was to see penguins declining, it was rewarding to have finally figured out the correlation," Wayne Trivelpiece says.
He believes that the shrinking population is due to the deaths of baby penguins. After their parents leave them to fend for themselves, young penguins stand around before venturing into the sea to search for a decreasing number of krill. Without any guidance, their probability of encountering a krill and knowing what to do with it is very low. Some years, only 10% of the young penguins return, down from 50% in the 1970s. By contrast, Gentoo penguins take their young on hunting trips before abandoning them; their numbers haven't fallen as severely.
Penguins, Fraser says, are a bellwether for how global warming will harm species across the globe. "If what we've seen in 35 years is just the precursor to what occurs across the planet, it's reason to be very concerned," he says. Although he still believes that sea ice loss is responsible for penguin decline in at least some areas, he calls the new study "one of the best papers I've read in quite a while so far as providing a description of the complexity and issues involved" in tracking food webs in the Antarctic.
Fraser calls the data set "formidable" evidence for long-term warming trends, adding that Antarctic research is the longest database in the world of population trends in large animals. "It's a great piece of work and I'm thankful for scientists like them who make such a commitment," adds oceanographer Oscar Schofield of Rutgers University in New Brunswick, New Jersey.
Trivelpiece WZ, Hinke JT, Miller AK, Reiss CS, Trivelpiece SG, Watters GM. Variability in krill biomass links harvesting and climate warming to penguin population changes in Antarctica. Proceedings of the National Academy of Sciences. http://www.pnas.org/content/early/2011/04/06/1016560108.full.pdf
The West Antarctic Peninsula (WAP) and adjacent Scotia Sea support abundant wildlife populations, many of which were nearly extirpated by humans. This region is also among the fastest-warming areas on the planet, with 5–6 °C increases in mean winter air temperatures and associated decreases in winter sea-ice cover. These biological and physical perturbations have affected the ecosystem profoundly. One hypothesis guiding ecological interpretations of changes in top predator populations in this region, the “sea-ice hypothesis,” proposes that reductions in winter sea ice have led directly to declines in “ice-loving” species by decreasing their winter habitat, while populations of “ice-avoiding” species have increased. However, 30 y of field studies and recent surveys of penguins throughout the WAP and Scotia Sea demonstrate this mechanism is not controlling penguin populations; populations of both ice-loving Adélie and ice-avoiding chinstrap penguins have declined significantly. We argue in favor of an alternative, more robust hypothesis that attributes both increases and decreases in penguin populations to changes in the abundance of their main prey, Antarctic krill. Unlike many other predators in this region, Adélie and chinstrap penguins were never directly harvested by man; thus, their population trajectories track the impacts of biological and environmental changes in this ecosystem. Linking trends in penguin abundance with trends in krill biomass explains why populations of Adélie and chinstrap penguins increased after competitors (fur seals, baleen whales, and some fishes) were nearly extirpated in the 19th to mid-20th centuries and currently are decreasing in response to climate change.
Melting Antarctic Ice Causing Penguins to Starve - ScienceNOW
Sara Reardon
11 April 2011
Every year since 1979, marine biologist Wayne Trivelpiece and his wife, Susan, both of the National Oceanic and Atmospheric Association's Antarctic Ecosystem Research Division in San Diego, California, have braved frigid temperatures and wind speeds that average 40 kilometers per hour to track the feeding, breeding, and migrating of chinstrap and Adelie penguins. During this time, populations they studied on the West Antarctic Peninsula and in the nearby Scotia Sea have declined drastically, and a few have gone extinct, victims of a warming planet that deprives them of their sea ice habitat. Now, in a compilation of over 30 years of data collected from numerous bases around Antarctica, the researchers conclude that the penguins are not only running out of room but also starving.
In 1992, the pair published a paper with ecologist William Fraser, now president of the privately owned Polar Ocean Research Group based in Sheridan, Montana, proposing what they deemed the "habitat hypothesis," the idea that melting sea ice along the Antarctic coast was harming penguins. The average temperature in the region of the Scotia Sea, one of the most rapidly warming places on the planet, has increased by 5?C to 6?C over the past 50 years, drastically reducing the amount of sea ice present and the length of time that the ice exists. The researchers proposed that losing their habitat was what was killing Adelie penguins, which need ice to survive. By contrast, the numbers of chinstrap penguins, which avoid sea ice as much as possible, were booming.
But by incorporating data from land-based stations and tourist ships that moonlight as penguin-counting research vessels, the researchers have expanded their data set and reexamined it. In a paper published today in the Proceedings of the National Academy of Sciences, the Trivelpieces and their colleagues propose that a decrease in krill—shrimplike crustaceans that are a staple food for penguins—is to blame for the decline in Adelie penguins and chinstrap penguins, whose populations are now shrinking by 2.9% and 4.3%, respectively, each year. As it turns out, krill larvae are as dependent on sea ice as Adelie penguins are, feeding on algae that grow on the underside of ice packs; krill numbers have dropped by 80% since 1981. Independent of whether they like ice, Adelie and chinstrap penguins like to eat krill.
Back in the 1980s, Wayne Trivelpiece says, when researchers first started noticing a rapid decline in penguin populations, it was unclear what the reason was. To check their hunch that the cause was a food shortage, they began forcing penguin parents returning from the sea to vomit by inverting them over a bucket and pushing on their stomachs. Chinstrap penguins, they and other researchers found, eat krill exclusively; Adelie penguins are dependent on it as well. Continuing research through the 1990s showed that the size of the krill was uniform, suggesting that only a few krill populations were maturing over the years and were available for penguins to eat. Satellite data showed that krill numbers fell in areas where sea ice dwindled. "As aggravating as it was to see penguins declining, it was rewarding to have finally figured out the correlation," Wayne Trivelpiece says.
He believes that the shrinking population is due to the deaths of baby penguins. After their parents leave them to fend for themselves, young penguins stand around before venturing into the sea to search for a decreasing number of krill. Without any guidance, their probability of encountering a krill and knowing what to do with it is very low. Some years, only 10% of the young penguins return, down from 50% in the 1970s. By contrast, Gentoo penguins take their young on hunting trips before abandoning them; their numbers haven't fallen as severely.
Penguins, Fraser says, are a bellwether for how global warming will harm species across the globe. "If what we've seen in 35 years is just the precursor to what occurs across the planet, it's reason to be very concerned," he says. Although he still believes that sea ice loss is responsible for penguin decline in at least some areas, he calls the new study "one of the best papers I've read in quite a while so far as providing a description of the complexity and issues involved" in tracking food webs in the Antarctic.
Fraser calls the data set "formidable" evidence for long-term warming trends, adding that Antarctic research is the longest database in the world of population trends in large animals. "It's a great piece of work and I'm thankful for scientists like them who make such a commitment," adds oceanographer Oscar Schofield of Rutgers University in New Brunswick, New Jersey.
Trivelpiece WZ, Hinke JT, Miller AK, Reiss CS, Trivelpiece SG, Watters GM. Variability in krill biomass links harvesting and climate warming to penguin population changes in Antarctica. Proceedings of the National Academy of Sciences. http://www.pnas.org/content/early/2011/04/06/1016560108.full.pdf
The West Antarctic Peninsula (WAP) and adjacent Scotia Sea support abundant wildlife populations, many of which were nearly extirpated by humans. This region is also among the fastest-warming areas on the planet, with 5–6 °C increases in mean winter air temperatures and associated decreases in winter sea-ice cover. These biological and physical perturbations have affected the ecosystem profoundly. One hypothesis guiding ecological interpretations of changes in top predator populations in this region, the “sea-ice hypothesis,” proposes that reductions in winter sea ice have led directly to declines in “ice-loving” species by decreasing their winter habitat, while populations of “ice-avoiding” species have increased. However, 30 y of field studies and recent surveys of penguins throughout the WAP and Scotia Sea demonstrate this mechanism is not controlling penguin populations; populations of both ice-loving Adélie and ice-avoiding chinstrap penguins have declined significantly. We argue in favor of an alternative, more robust hypothesis that attributes both increases and decreases in penguin populations to changes in the abundance of their main prey, Antarctic krill. Unlike many other predators in this region, Adélie and chinstrap penguins were never directly harvested by man; thus, their population trajectories track the impacts of biological and environmental changes in this ecosystem. Linking trends in penguin abundance with trends in krill biomass explains why populations of Adélie and chinstrap penguins increased after competitors (fur seals, baleen whales, and some fishes) were nearly extirpated in the 19th to mid-20th centuries and currently are decreasing in response to climate change.
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