Martin W

Fewer caribou calves are being born and more of them are dying in West Greenland as a result of a warming climate, according to Eric Post, a Penn State associate professor of biology. Post, who believes that caribou may serve as an indicator species for climate changes including global warming, based his conclusions on data showing that the timing of peak food availability no longer corresponds to the timing of caribou births.
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caribou are unable to keep pace with certain changes that have occurred as a result of global warming. When the animals arrive at their calving grounds now, pregnant females find that the plants on which they depend already have reached peak productivity and have begun to decline in nutritional value. According to Post, the plants — which initiate growth in response to temperature, not day length — are peaking dramatically earlier in response to rising temperatures. “Spring temperatures at our study site in West Greenland have risen by more than 4 degrees Celsius over the past few years,” said Post. “As a result, the timing of plant growth has advanced, but calving has not.”

A proposed solution to reverse the effects of global warming by spraying sulfate particles into Earth’s stratosphere could make matters much worse, climate researchers said on Thursday.

They said trying to cool off the planet by creating a kind of artificial sun block would delay the recovery of the Antarctic ozone hole by 30 to 70 years and create a new loss of Earth’s protective ozone layer over the Arctic.

“What our study shows is if you actually put a lot of sulfur into the atmosphere we get a larger ozone depletion than we had before,” said Simone Tilmes of the National Center for Atmospheric Research in Boulder, Colorado, whose research appears in the journal Science.

Climate change could cause global conflicts as large as the two World Wars which will last for centuries unless it is controlled, a leading defence think tank has warned.

The Royal United Services Institute said a tenfold increase in research spending, comparable to the amount spent on the Apollo space programme, will be needed if the world is to avoid the worst effects of changing temperatures.
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The report said: “If climate change is not slowed and critical environmental thresholds are exceeded, then it will become a primary driver of conflicts between and within states.”

It added: “Climate impacts will force us into a radical rethink of how we identify and secure our national interests. For example, our energy and climate security will increasingly depend on stronger alliances with other large energy consumers, such as China, to develop and deploy new energy technologies, and less on relations with oil producing states.

“No strategy for long run peace and stability in Afghanistan can possibly succeed unless local livelihoods can survive the impact of a changing climate on water availability and crop yields.”

Sea levels could rise by up to one-and-a-half metres by the end of this century, according to a new scientific analysis.

This is substantially more than the Intergovernmental Panel on Climate Change (IPCC) forecast in last year’s landmark assessment of climate science.
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The new analysis comes from a UK/Finnish team which has built a computer model linking temperatures to sea levels for the last two millennia.

“For the past 2,000 years, the [global average] sea level was very stable, it only varied by about 20cm,” said Svetlana Jevrejeva from the Proudman Oceanographic Laboratory (POL), near Liverpool, UK.

“But by the end of the century, we predict it will rise by between 0.8m and 1.5m.

“The rapid rise in the coming years is associated with the rapid melting of ice sheets.”

The world’s glaciers are melting faster than at any time since records began, threatening catastrophe for hundreds of millions of people and their eco-systems.

The details are revealed in the latest report from the World Glacier Monitoring Service and will add to growing alarm about the rise in sea levels and increased instances of flooding, avalanches and drought.

Based on historical records and other evidence, the rate at which the glaciers are melting is also thought to be faster that at any time in the past 5,000 years, said Professor Wilfried Haeberli, director of the monitoring service. ‘There’s no absolute proof, but nevertheless the evidence is strong: this is really extraordinary.’

Experts have been monitoring 30 glaciers around the world for nearly three decades and the most recent figures, for 2006, show the biggest ever ‘net loss’ of ice. Achim Steiner, head of the UN Environment Programme (UNEP), told The Observer that melting glaciers were now the ‘loudest and clearest’ warning signal of global warming.

The problem could lead to failing infrastructure, mass migration and even conflict. ‘We’re talking about something that happens in your and my lifespan. We’re not talking about something hypothetical, we’re talking about something dramatic in its consequences,’ he said

General Motors Corp Vice Chairman Bob Lutz has defended remarks he made dismissing global warming as a “total crock of shit,” saying his views had no bearing on GM’s commitment to build environmentally friendly vehicles.

Lutz, GM’s outspoken product development chief, has been under fire from Internet bloggers since last month when he was quoted as making the remark to reporters in Texas.

Unique marine life in Antarctica will be at risk from an invasion of sharks, crabs and other predators if global warming continues, scientists warn.

Crabs are poised to return to the Antarctic shallows, threatening creatures such as giant sea spiders and floppy ribbon worms, says a UK-US team.

Some have evolved without predators for tens of millions of years.

Bony fish and sharks would move in if waters warm further, threatening species with extinction, they say.

In the last 50 years, sea surface temperatures around Antarctica have risen by 1 to 2C, which is more than twice the global average.

Anthropogenic forcing could push the Earth’s climate system past critical thresholds, so that important components may “tip” into qualitatively different modes of operation. In the renowned magazine “Proceedings of the National Academy of Sciences” (PNAS) an international team of researchers describes, where small changes can have large long-term consequences on human and ecological systems.

“Society may be lulled into a false sense of security by smooth projections of global change,“ the researchers around Timothy Lenton from the British University of East Anglia in Norwich and Hans Joachim Schellnhuber from the Potsdam Institute for Climate Impact Research report. Global change may appear to be a slow and gradual process on human scales. However, in some regions anthropogenic forcing on the climate system could kick start abrupt and potentially irreversible changes. For these sub-systems of the Earth system the researchers introduce the term “tipping element”.

Drawing on a workshop of 36 leading climate scientists in October 2005 at the British Embassy, Berlin, Germany, a further elicitation of 52 experts in the field, and a review of the pertinent literature, the authors compiled a short-list of nine potential tipping elements. These tipping elements are ranked as the most policy-relevant and require consideration in international climate politics.

Arctic sea-ice and the Greenland Ice Sheet are regarded as the most sensitive tipping elements with the smallest uncertainty. Scientists expect ice cover to dwindle due to global warming. The West Antarctic Ice Sheet is probably less sensitive as a tipping element, but projections of its future behavior have large uncertainty. This also applies to the Amazon rainforest and Boreal forests, the El Niño phenomenon, and the West African monsoon. “These tipping elements are candidates for surprising society by exhibiting a nearby tipping point,” the authors state in the article that is published in PNAS Online Early Edition. The archetypal example of a tipping element, the Atlantic thermohaline circulation, could undergo a large abrupt transition with up to ten percent probability within this century, according to the UN climate report from 2007.

Given the scale of potentially dramatic impacts from tipping elements the researchers anticipate stronger mitigation. Concepts for adaptation that go beyond current incremental approaches are also necessary. In addition, “a rigorous study of potential tipping elements in human socio-economic systems would also be welcome,” the researchers write. Some models suggest there are tipping points to be passed for the transition to a low carbon society.

Highly sensitive tipping elements, smallest uncertainty:

Greenland Ice Sheet – Warming over the ice sheet accelerates ice loss from outlet glaciers and lowers ice altitude at the periphery, which further increases surface temperature and ablation. The exact tipping point for disintegration of the ice sheet is unknown, since current models cannot capture the observed dynamic deglaciation processes accurately. But in a worst case scenario local warming of more than three degrees Celsius could cause the ice sheet to disappear within 300 years. This would result in a rise of sea level of up to seven meters.

Arctic sea-ice – As sea-ice melts, it exposes a much darker ocean surface, which absorbs more radiation than white sea-ice so that the warming is amplified. This causes more rapid melting in summer and decreases ice formation in winter. Over the last 16 years ice cover during summer declined markedly. The critical threshold global mean warming may be between 0.5 to 2 degrees Celsius, but could already have been passed. One model shows a nonlinear transition to a potential new stable state with no arctic sea-ice during summer within a few decades.

Intermediately sensitive tipping elements, large uncertainty:

West Antarctic Ice Sheet – Recent gravity measurements suggest that the ice sheet is losing mass. Since most of the ice sheet is grounded below sea level the intrusion of ocean water could destabilize it. The tipping point could be reached with a local warming of five to eight degrees Celsius in summer. A worst case scenario shows the ice sheet could collapse within 300 years, possibly raising sea level by as much as five meters.

Boreal forest – The northern forests exhibit a complex interplay between tree physiology, permafrost and fire. A global mean warming of three to five degrees Celsius could lead to large-scale dieback of the boreal forests within 50 years. Under climate change the trees would be exposed to increasing water stress and peak summer heat and would be more vulnerable to diseases. Temperate tree species will remain excluded due to frost damage in still very cold winters.

Amazon rainforest – Global warming and deforestation will probably reduce rainfall in the region by up to 30 percent. Lengthening of the dry season, and increases in summer temperatures would make it difficult for the forest to re-establish. Models project dieback of the Amazon rainforest to occur under three to four degrees Celsius global warming within fifty years. Even land-use change alone could potentially bring forest cover to a critical threshold.

El Niño Southern Oscillation (ENSO) – The variability of this ocean-atmosphere mode is controlled by the layering of water of different temperatures in the Pacific Ocean and the temperature gradient across the equator. During the globally three degrees Celsius warmer early Pliocene ENSO may have been suppressed in favor of persistent El Niño or La Niña conditions. In response to a warmer stabilized climate, the most realistic models simulate increased El Niño amplitude with no clear change in frequency.

Sahara/Sahel- and West African monsoon – The amount of rainfall is closely related to vegetation climate feedback and sea surface temperatures of the Atlantic Ocean. Greenhouse gas forcing is expected to increase Sahel rainfall. But a global mean warming of three to five degrees Celsius could cause a collapse of the West African monsoon. This could lead either to drying of the Sahel or to wetting due to increased inflow from the West. A third scenario shows a possible doubling of anomalously dry years by the end of the century.

Indian summer monsoon – The monsoon circulation is driven by a land-to-ocean pressure gradient. Greenhouse warming tends to strengthen the monsoon since warmer air can carry more water. Air pollution and land-use that increases the reflection of sunlight tend to weaken it. The Indian summer monsoon could become erratic and in the worst case start to chaotically change between an active and a weak phase within a few years.

Lowly sensitive tipping elements, intermediate uncertainty:

Atlantic thermohaline circulation – The circulation of sea currents in the Atlantic Ocean is driven by seawater that flows to the North Atlantic, cools and sinks at high latitudes. If the inflow of freshwater increases, e.g. from rivers or melting glaciers, or the seawater is warmed, its density would decrease. A global mean warming of three to five degrees Celsius could push the element past the tipping point so that deep water formation stops. Under these conditions the North Atlantic current would be disrupted, sea level in the North Atlantic region would rise and the tropical rain belt would be shifted.

Global warming could reduce how many hurricanes hit the United States, according to a new federal study that clashes with other research. The new study is the latest in a contentious scientific debate over how man-made global warming may affect the intensity and number of hurricanes. In it, researchers link warming waters, especially in the Indian and Pacific oceans, to increased vertical wind shear in the Atlantic Ocean near the United States. Wind shear — a change in wind speed or direction — makes it hard for hurricanes to form, strengthen and stay alive. So that means "global warming may decrease the likelihood of hurricanes making landfall in the United States," according to researchers at the National Oceanic and Atmospheric Administration’s Miami Lab and the University of Miami. … Critics say Wang’s study is based on poor data that was rejected by scientists on the Nobel Prize-winning Intergovernmental Panel on Climate Change. They said that at times only one in 10 North Atlantic hurricanes hit the U.S. coast and the data reflect only a small percentage of storms around the globe.

The Democrats (a.k.a. global warming wimps) have found the rhetorical weapon they will use for at least the next decade to decrease your liberty while increasing their power, and that weapon is the hysteria over global warming. … Environmental doomsaying is one of the most powerful tactics that liberals use to obtain and wield power. At its heart, the Democrat Party is a coalition of interest groups that feed at the trough of the government. The more power the politicians and bureaucrats have, the more contracts and benefits the groups can gobble up. … Everything you do has a carbon footprint and could be regulated by the government. If the Democrats have their way, you could face new limits on what you eat for breakfast, the way you travel to work, the computer on which you read Townhall.com, the medicines you take, the clothes you wear, the DVDs you watch, everything – everything! “Carbon footprint” is code for limitless government intrusion into every detail of your life.

Dr. Derocher is a polar bear scientist with the University of Edmonton in Canada. He also serves on PBI’s Scientific Advisory Council.
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The various presentations of biased reporting ignore, or are ignorant of, the different reasons for changes in populations. If I thought that there were more bears now than 50 years ago and a reasonable basis to assume this would not change, then no worries. This is not the case.

The bottom line here is that it is an apples and oranges issue. The early estimates of polar bear abundance are a guess. There is no data at all for the 1950-60s. Nothing but guesses. We are sure the populations were being negatively affected by excess harvest (e.g., aircraft hunting, ship hunting,self-killing guns, traps, and no harvest limits). The harvest levels were huge and growing. The resulting low numbers of bears were due only to excess harvest but, again, it was simply a guess as to the number of bears.

After the signing of the International Agreement on Polar Bears in the 1970s, harvests were controlled and the numbers increased.
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There is, however, very strong evidence for a decline in Western Hudson Bay and the Southern Beaufort Sea based on quantitative studies. More recently, scientists working in the Southern Hudson Bay have reported a major decline in the condition of polar bears. A decline in condition was the precursor to the population decline in Western Hudson Bay. There is clear suggestion of a population decline due to over-harvest in Baffin Bay, Kane Basin and possibly Norwegian Bay.
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Look at the messengers: lobby groups for big business say there is no problem.
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Comparing declines caused by harvest followed by recovery from harvest controls to declines from loss of habitat and climate warming are apples and oranges. Ignorant people write ignorant things.