Human-Induced Climate Change Now Feared Irreversible

[Frodo]

Climate change 'irreversible' as Arctic sea ice fails to re-form

By Steve Connor, Science Editor
Published: 14 March 2006

Sea ice in the Arctic has failed to re-form for the second consecutive winter, raising fears that global warming may have tipped the polar regions in to irreversible climate change far sooner than predicted.

Satellite measurements of the area of the Arctic covered by sea ice show that for every month this winter, the ice failed to return even to its long-term average rate of decline. It is the second consecutive winter that the sea ice has not managed to re-form enough to compensate for the unprecedented melting seen during the past few summers.

Scientists are now convinced that Arctic sea ice is showing signs of both a winter and a summer decline that could indicate a major acceleration in its long-term rate of disappearance. The greatest fear is that an environmental "positive feedback" has kicked in, where global warming melts ice which in itself causes the seas to warm still further as more sunlight is absorbed by a dark ocean rather than being reflected by white ice.

Mark Serreze, a sea ice specialist at the US National Snow and Ice Data Centre in Colorado, said: "In September 2005, the Arctic sea ice cover was at its lowest extent since satellite monitoring began in 1979, and probably the lowest in the past 100 years. While we can't be certain, it looks like 2006 will be more of the same," Dr Serreze said.

"Unless conditions turn colder, we may be headed for another year of big sea ice losses, rivalling or perhaps even exceeding what we saw in September 2005. We are of course monitoring the situation closely ... Coupled with recent findings from Nasa that the Greenland ice sheet may be near a tipping point, it's pretty clear that the Arctic is starting to respond to global warming," he added.

source

[Undisguised Sockpuppet]

Well looks like our future will become like the one in http://www.worlddreambank.org/D/DUBIA.HTM sooner than 1000 years from now...

[John Dibble]

Well looks like our future will become like the one in http://www.worlddreambank.org/D/DUBIA.HTM sooner than 1000 years from now...

Unlikely. Before the ice caps melted to that point, the great conveyer belt(thermohaline circulation) would greatly weaken or even shut down due to the decreased salinity of the oceans.



This would result in lower temperatures - temperatures low enough for an ice age. You'll note that places in Europe such as Scandanavia are in lattitudes similar to Alaska or even the permafrosted areas of Canada and Siberia, yet their climates are more like North America. This is due to the warm air and water brought by the great conveyer belt. These places would be much colder without it, and ice would result. This theory is the premise behind the movie "The Day After Tommorow", though that film exaggerates it - rather than the entire thing happening in a day it would be a process of about a decade or so.

It should also be noted that this has happened multiple times over the course of Earth's history - the ice caps are not always the same. Sometimes they grow, other times they shrink.

[Undisguised Sockpuppet]

Well looks like our future will become like the one in http://www.worlddreambank.org/D/DUBIA.HTM sooner than 1000 years from now...

Unlikely. Before the ice caps melted to that point, the great conveyer belt(thermohaline circulation) would greatly weaken or even shut down due to the decreased salinity of the oceans.



This would result in lower temperatures - temperatures low enough for an ice age. You'll note that places in Europe such as Scandanavia are in lattitudes similar to Alaska or even the permafrosted areas of Canada and Siberia, yet their climates are more like North America. This is due to the warm air and water brought by the great conveyer belt. These places would be much colder without it, and ice would result. This theory is the premise behind the movie "The Day After Tommorow", though that film exaggerates it - rather than the entire thing happening in a day it would be a process of about a decade or so.

Global Warming doesn't mean it all gets warmer everywhere at once. It means the average global temperature is rising. Europe and Eastern north america will probably end up colder in the early stages of the warmup due to the gulf stream shutting down.

[John Dibble]

Global Warming doesn't mean it all gets warmer everywhere at once. It means the average global temperature is rising. Europe and Eastern north america will probably end up colder in the early stages of the warmup due to the gulf stream shutting down.

I'm quite aware global warming is about average temperature, but what I'm talking about is how modern science is showing the idea of the flooded earth from the site you linked is unlikely. That idea predated today's knowledge of the effects of the great conveyor belt. Here's a more detailed explanation:

http://www.commondreams.org/views04/0130-11.htm

[Filuwaúrdjan]

Climate Change is *always* irreversible... do people actually understand the difference between climate and weather?

[Bono]

Well looks like our future will become like the one in http://www.worlddreambank.org/D/DUBIA.HTM sooner than 1000 years from now...

Unlikely. Before the ice caps melted to that point, the great conveyer belt(thermohaline circulation) would greatly weaken or even shut down due to the decreased salinity of the oceans.



This would result in lower temperatures - temperatures low enough for an ice age. You'll note that places in Europe such as Scandanavia are in lattitudes similar to Alaska or even the permafrosted areas of Canada and Siberia, yet their climates are more like North America. This is due to the warm air and water brought by the great conveyer belt. These places would be much colder without it, and ice would result. This theory is the premise behind the movie "The Day After Tommorow", though that film exaggerates it - rather than the entire thing happening in a day it would be a process of about a decade or so.

It should also be noted that this has happened multiple times over the course of Earth's history - the ice caps are not always the same. Sometimes they grow, other times they shrink.

So do you believe that there will be huge snowsotrsm that will destroy everything above teh mason dixon line, except that theyll be in a perid of ten years and not a few days?

[John Dibble]

So do you believe that there will be huge snowsotrsm that will destroy everything above teh mason dixon line, except that theyll be in a perid of ten years and not a few days?

No. The ice age due to global warming is what I was saying the movie was based on, not the storm thing. Their version is "OMFG, ICE AGE IN A FEW DAYS, MASSIVE STORMS! ARRRGH!" while the realistic version is "Hmm, we seem to be getting more snow every year, and the ice caps are growing".

[Gabu]

So do you believe that there will be huge snowsotrsm that will destroy everything above teh mason dixon line, except that theyll be in a perid of ten years and not a few days?

No. The ice age due to global warming is what I was saying the movie was based on, not the storm thing. Their version is "OMFG, ICE AGE IN A FEW DAYS, MASSIVE STORMS! ARRRGH!" while the realistic version is "Hmm, we seem to be getting more snow every year, and the ice caps are growing".

The Earth is remarkable in its ability to compensate for things that attempt to adversely affect the conditions present on its surface.  The Earth is still likely going to be here after everything that humans do to it.  The challenge for humans is not really to avoid murdering the Earth, but to avoid getting killed when the Earth compensates for what they do to it.

[Frodo]

Thought I'd add this to the discussion:

Winter warmest ever on record in Canada

THE ASSOCIATED PRESS

TORONTO -- The winter of 2005-2006 has been Canada's warmest on record and the federal agency Environment Canada said Monday it was investigating whether it's a sign of global warming.

Between December and February, the country was 3.9 degrees above normal - the warmest winter season since temperatures were first recorded in 1948. Environment Canada climatologist Bob Whitewood said it smashed the previous record set in 1987 by 0.9 degrees.

"We saw it coming from mid-January on that we were seeing something quite remarkable," Whitewood said.

The experience has been similar south of the border where the U.S. National Climatic Data Center said the winter has been the fifth warmest on record. December through February are considered meteorological winter.

It was especially balmy in Alberta, Saskatchewan and the Northwest Territories, where temperatures were 6 to 8 degrees above normal.

Whitewood said the last 10 winters have been warmer than normal and along with this winter reflect a trend that could be explained as global warming. He said Environment Canada would spend the next year examining the data to see if it's an aberration or evidence of a trend.

source

[MasterJedi]

What Dibble is saying is true, we'll probably have at least a decade of really cold, really snowy weather where everything gets horrible and most of the crops in the north are crap.

[○∙◄☻¥tπ[╪AV┼cVê└]

Well, it's obvious that the greenhouse gases have led to climate change. Well, obvious to anyone who agrees that 9i40 heads and 60 tails are statistically significant.

[The Dowager Mod]

Well, it's obvious that the greenhouse gases have led to climate change. Well, obvious to anyone who agrees that 9i40 heads and 60 tails are statistically significant.

It's just a "realignment", HAHAHAHAHA but of course these are the same idiots that believe in the "science" of creationism".

[Undisguised Sockpuppet]

I see cold weather as bad so global warming can't be a bad thing. And if the sea levels rise. Good. It just displaces a bunch of osutherners and midwesterners.

[MODU]

Just as a show of hands of all the people preaching gloom and doom . . . how many of you have planted more than one tree this year?

For those of you saying "calm down kids, the Earth will take care of herself," how many of you have planted more than one tree this year?

It's easy to talk about the climate, and what we need to do, but ya know what really changes things?  Acta non verba . . . Deeds, not words.  Go out there and plant a tree on the west-facing side of your house.  As the tree grows, it will absorb some of the carbon dioxide in the air while offering shade to your house in the afternoon, providing a cooling effect so you don't have to use more energy to run your A/C in the Summer, lowering the demand on the power plants...........  You get the point.

[John Dibble]

For those of you saying "calm down kids, the Earth will take care of herself," how many of you have planted more than one tree this year?

Why should we plant trees? The Earth will take care of itself!

[MODU]

For those of you saying "calm down kids, the Earth will take care of herself," how many of you have planted more than one tree this year?

Why should we plant trees? The Earth will take care of itself!

hahahaha

[nlm]

The Earth is remarkable in its ability to compensate for things that attempt to adversely affect the conditions present on its surface.  The Earth is still likely going to be here after everything that humans do to it.  The challenge for humans is not really to avoid murdering the Earth, but to avoid getting killed when the Earth compensates for what they do to it.

Yep.

[Frodo]

It appears there is scientific evidence emerging that global warming is as much a product of naturally-occuring climate cycles as human-induced greenhouse gases, after all:
-------------------------------------------------------

Pacific Ocean temperature changes point to natural climate variability

Nov. 13, 2002
Texas A&M University

COLLEGE STATION - Analysis of long-term changes in Pacific Ocean temperatures may provide additional data with which to evaluate global warming hypotheses.

"Abrupt changes in water temperatures occurring over intervals of up to 25 years suggest that global warming may result as much from natural cyclical climate variations as from human activity," said Benjamin Giese, oceanography professor in the College of Geosciences.

"Climate models constructed here at Texas A&M University were used to analyze ocean surface temperature records in the tropical Pacific since 1950.  The results suggest that as much as one-half of all global surface warming since the 1970's may be part of natural variation as distinct from the result of greenhouse gases,"

Giese and graduate student Amy J. Bratcher published the results of their analysis in the Oct. 8 issue of Geophysical Research Letters.

Surface air temperature records maintained over the past 120 years serve as the main evidence for hypotheses linking global warming to increased greenhouse gases generated by manmade (anthropogenic) causes. These records show the average global air temperature has risen by about one-half degree Centigrade over the last 50 years. But while the general air temperature trend seems to be undisputedly upward, this upward trend varies considerably.

"How much of this variability is attributable to natural variations and how much is due to anthropogenic contributions to atmospheric greenhouse gases has not yet been resolved," Giese said. "Recent studies indicate that it is difficult to separate intrinsic natural variance from anthropogenic forcing in the climate system."

Giese believes their analysis of tropical Pacific Ocean data indicates long-term upward changes in ocean temperatures precede global surface air temperature changes by about four years. These ocean temperature fluctuations are in turn preceded by an increase in subsurface water temperatures by about seven years.

"Thus, the results suggest that much of the decade to decade variations in global air temperature may be attributed to tropical Pacific decadal variability," Giese observed. "The results also suggest that subsurface temperature anomalies in the southern tropical Pacific can be used as a predictor of decadal variations of global surface air temperature."

For example, in 1976 an abrupt change in the temperature of the tropical Pacific Ocean preceded a rise of two-tenths of a degree in global air temperatures.

"This phenomenon looks like El Nino, but with a much longer time scale - El Nino occurs over a period of from nine to 12 months, but this fluctuation lasts for about 25 years," he continued. "In 1976, the ocean temperature change in question occurred very quickly, moving from cooler than normal to warmer than normal in about a year."

Bratcher and Giese report that now conditions in the tropical Pacific are similar to those prior to the 1976 climate shift, except with the opposite sign. If conditions develop in a similar way, then the tropical Pacific could cool back to pre-1976 conditions.

"The subsurface tropical Pacific has shown a distinct cooling trend over the last eight years, so the possibility exists that the warming trend in global surface air temperature observed since the late 1970's may soon weaken," Giese observed.

"This natural variation would help to counter the greenhouse gas warming effect. In fact, careful study reveals that global warming and cooling has occurred in the past in cyclical patterns."

Giese's work involves constructing computer models that incorporate years of weather data to reveal recurring patterns of oscillation and help identify mechanisms that may affect climate. He focuses on climate oscillations that are not directly forced by such things as changing amounts of sunlight, but instead are mechanisms of internal climatic variation for which scientists have as yet isolated no particular cause.

"Our model results terminated at the end of 2001," he said. "Now we're waiting to see what their long-term effects may be on global temperatures.

"Our results don't preclude the possibility that anthropogenic sources of greenhouse gases have contributed to global warming. We're just suggesting that the human forced portion of global warming may be less than previously described."

[WMS]

Regardless of the reversibility or not of this, the International Green Left is going to have to come up with a better solution than "DESTROY THE AMERICAN ECONOMY!"