Okay, so now I’m going to scare you.
Today’s subject is global warming. There’s a huge amount of material that has come out today on the subject, in many well-considered journals.
First, the summary:
Global Warming: A New Worst Case
by melvin
Fri Feb 17, 2006 at 03:02:21 AM PDT
(From the diaries -- Plutonium Page.)
No worst, there is none. Pitched past pitch of grief, More pangs will, schooled at forepangs, wilder wring.--Gerard Manley Hopkins
Gerard expresses pretty well what we're feeling on all fronts. On the subject of global warming, Glacial Melting Accelerates, a diary last night, cites recent reports that the Greenland ice sheet is melting twice as fast as we thought. Now a complementary and reinforcing article in New Scientist will project beyond 2100 the consequences of using all the fossil fuels still underground: just for starters, a sea level rise of 11 meters (36 feet).
The article is behind a subscription wall. Worst case global warming scenario revealed Rather than rehearse doomsday again, and risk the wrath of their serious copyright police, we'll skip to the money quote from the study's author:
Only by starting to reduce carbon dioxide emissions now can we avoid the melting of the Greenland ice cap.
NB: Not by reducing the rate at which emissions are rising, not by some emissions trading slight of hand, counting trees we don't cut down as if that actually reduced emissions, but by reducing them, for real, now. The author is also concerned that the Antarctic sheet may go next. He sees a very steep temperature curve coming, and stopping well short of "worst case" will leave London (and Amsterdam, and Bangladesh . . .) under only a few feet less of seawater.
Meanwhile, Bush's ally on this front as on all things twisted and wrong is the Howard government of Australia. In a revelation that should surprise no one here, it's been revealed that science has been hushed there too:
Scientists in Aus Pressured not to Disclose Global Warming
Three Australian scientists said they were pressured by the government not to issue any statements on global warming.
The former head of the climate department at the independent institution, Commonwealth Scientific and Industrial Research Organization, Graeme Pearman told ABC TV Monday, "I was told not to say anything that contradicts the policy of the government."
Pearman went on to say that he had been censured at least six times last year.~~~~~Barrie Pittock, also from the same institution, said they have been under pressure to remove information on global warming from any official documents.
(This was also reported in the Guardian)Further food for thought on Science Friday: Do we laugh or cry at the following? CSIRO (the Commonwealth Scientific and Industrial Research Organisation) worked long and hard to figure this one out. From The Age: Fires up as world warms
Global warming will cause more bushfires by 2020, increasing destruction of the environment and causing more health problems and fire-related injury and death, a new report says.~~~~~The report said increased fires would mean even higher greenhouse gas emissions, greater destruction of ecosystems and forests, and more damage to property, livestock and crops.
Pretty much anyone could have figured that out before coffee, one would think, but the bold portion does give pause.
What does anyone think about the idea of a carbon tax? Seriously. bonddad, Jerome, Darksyde? Anyone at all?
From today’s Washington Post
http://www.washingtonpost.com/wp-dyn/content/article/2006/02/16/AR2006021601292.html
Glacier Melt Could Signal Faster Rise in Ocean Levels
By Shankar Vedantam
Washington Post Staff WriterFriday, February 17, 2006; Page A01
Greenland's glaciers are melting into the sea twice as fast as previously believed, the result of a warming trend that renders obsolete predictions of how quickly Earth's oceans will rise over the next century, scientists said yesterday.
The new data come from satellite imagery and give fresh urgency to worries about the role of human activity in global warming. The Greenland data are mirrored by findings from Bolivia to the Himalayas, scientists said, noting that rising sea levels threaten widespread flooding and severe storm damage in low-lying areas worldwide.
The scientists said they do not yet understand the precise mechanism causing glaciers to flow and melt more rapidly, but they said the changes in Greenland were unambiguous -- and accelerating: In 1996, the amount of water produced by melting ice in Greenland was about 90 times the amount consumed by Los Angeles in a year. Last year, the melted ice amounted to 225 times the volume of water that city uses annually.
"We are witnessing enormous changes, and it will take some time before we understand how it happened, although it is clearly a result of warming around the glaciers," said Eric Rignot, a scientist at the California Institute of Technology's Jet Propulsion Laboratory.
The Greenland study is the latest of several in recent months that have found evidence that rising temperatures are affecting not only Earth's ice sheets but also such things as plant and animal habitats, coral reefs' health, hurricane severity, droughts, and globe-girdling currents that drive regional climates.
The ice sheets in Greenland and Antarctica are among the largest reservoirs of fresh water on Earth, and their fate is expected to be a major factor in determining how much the oceans will rise. Rignot and University of Kansas scientist Pannir Kanagaratnam, who published their findings yesterday in the journal Science, declined to guess how much the faster melting would raise sea levels but said current estimates of around 20 inches over the next century are probably too low.
While sea-level increases of a few feet may not sound like very much, they could have profound consequences on flood-prone countries such as Bangladesh and trigger severe weather around the world.
"The implications are global," said Julian Dowdeswell, a glacier expert at the University of Cambridge in England who reviewed the new paper for Science. "We are not talking about walking along the sea front on a nice summer day, we are talking of the worst storm settings, the biggest storm surges . . . you are upping the probability major storms will take place."
The study also highlights how seemingly small changes in temperature can have extensive effects. Where glaciers in Greenland were once traveling around four miles per year, they are now moving twice as fast. While it is possible that increased precipitation in northern Greenland is somehow compensating for the melting in the south, the scientists said that is unlikely.
There are multiple ways warming might be causing glaciers to accelerate. The scientists said increased temperatures may loosen the grip that glaciers have on underlying bedrock, or melt away floating shelves along the shore that can hold ice in place.
Whatever the mechanism, the phenomenon seems widespread. At a news conference organized by the American Association for the Advancement of Science at its annual meeting in St. Louis, glacier scientists Vladimir Aizen from the University of Idaho and Gino Casassa of Chile's Centro de Estudios Cientificos said they were seeing the same thing happen to glaciers in the Himalayas and South America.
"Glaciers have retreated systematically and in an accelerated fashion in the last few decades," Casassa said. One glacier that provided Bolivia with its only ski slope five years ago has splintered into three and cannot be used for skiing, the scientist added.
Rapid melting of Himalayan glaciers also raises concerns for the large portion of humankind that gets its fresh water from glacier-fed rivers in South Asia, Aizen noted.
Most climate scientists believe a major cause for Earth's warming climate is increased emissions of greenhouse gases as a result of burning fossil fuels, largely in the United States and other wealthy, industrialized nations such as those of western Europe but increasingly in rapidly developing nations such as China and India as well. Carbon dioxide and several other gases trap the sun's heat and raise atmospheric temperature.
"This study underscores the need to take swift, meaningful actions at home and abroad to address climate change," said Vicki Arroyo, director of policy analysis at the Pew Center on Global Climate Change.
The data highlight the lack of meaningful U.S. policy, she added: "This is the kind of study that should make people stay awake at night wondering what we're doing to the climate, how we're shaping the planet for future generations and, especially, what we can do about it."
From the Independent
Climate change: On the edge
Greenland ice cap breaking up at twice the rate it was five years ago, says scientist Bush tried to gag
By Jim Hansen
Published: 17 February 2006
A satellite study of the Greenland ice cap shows that it is melting far faster than scientists had feared - twice as much ice is going into the sea as it was five years ago. The implications for rising sea levels - and climate change - could be dramatic.
Yet, a few weeks ago, when I - a Nasa climate scientist - tried to talk to the media about these issues following a lecture I had given calling for prompt reductions in the emission of greenhouse gases, the Nasa public affairs team - staffed by political appointees from the Bush administration - tried to stop me doing so. I was not happy with that, and I ignored the restrictions. The first line of Nasa's mission is to understand and protect the planet.
This new satellite data is a remarkable advance. We are seeing for the first time the detailed behaviour of the ice streams that are draining the Greenland ice sheet. They show that Greenland seems to be losing at least 200 cubic kilometres of ice a year. It is different from even two years ago, when people still said the ice sheet was in balance.
Hundreds of cubic kilometres sounds like a lot of ice. But this is just the beginning. Once a sheet starts to disintegrate, it can reach a tipping point beyond which break-up is explosively rapid. The issue is how close we are getting to that tipping point. The summer of 2005 broke all records for melting in Greenland. So we may be on the edge.
Our understanding of what is going on is very new. Today's forecasts of sea-level rise use climate models of the ice sheets that say they can only disintegrate over a thousand years or more. But we can now see that the models are almost worthless. They treat the ice sheets like a single block of ice that will slowly melt. But what is happening is much more dynamic.
Once the ice starts to melt at the surface, it forms lakes that empty down crevasses to the bottom of the ice. You get rivers of water underneath the ice. And the ice slides towards the ocean.
Our Nasa scientists have measured this in Greenland. And once these ice streams start moving, their influence stretches right to the interior of the ice sheet. Building an ice sheet takes a long time, because it is limited by snowfall. But destroying it can be explosively rapid.
How fast can this go? Right now, I think our best measure is what happened in the past. We know that, for instance, 14,000 years ago sea levels rose by 20m in 400 years - that is five metres in a century. This was towards the end of the last ice age, so there was more ice around. But, on the other hand, temperatures were not warming as fast as today.
How far can it go? The last time the world was three degrees warmer than today - which is what we expect later this century - sea levels were 25m higher. So that is what we can look forward to if we don't act soon. None of the current climate and ice models predict this. But I prefer the evidence from the Earth's history and my own eyes. I think sea-level rise is going to be the big issue soon, more even than warming itself.
It's hard to say what the world will be like if this happens. It would be another planet. You could imagine great armadas of icebergs breaking off Greenland and melting as they float south. And, of course, huge areas being flooded.
How long have we got? We have to stabilise emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree. That will be warmer than it has been for half a million years, and many things could become unstoppable. If we are to stop that, we cannot wait for new technologies like capturing emissions from burning coal. We have to act with what we have. This decade, that means focusing on energy efficiency and renewable sources of energy that do not burn carbon. We don't have much time left.
Jim Hansen, the director of the Nasa Goddard Institute for Space Studies in New York, is President George Bush's top climate modeller. He was speaking to Fred Pearce
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