Consolidated Climate Change/CO2/Global Warming Thread

[RnR]

Can we keep at least this thread just about the science?

[ernie]

http://www.sciencedaily.com/releases...0130131509.htm

Was the Little Ice Age Triggered by Massive Volcanic Eruptions?

ScienceDaily (Jan. 30, 2012) — A new international study may answer contentious questions about the onset and persistence of Earth's Little Ice Age, a period of widespread cooling that lasted for hundreds of years until the late 19th century.

The study, led by the University of Colorado Boulder with co-authors at the National Center for Atmospheric Research (NCAR) and other organizations, suggests that an unusual, 50-year-long episode of four massive tropical volcanic eruptions triggered the Little Ice Age between 1275 and 1300 A.D. The persistence of cold summers following the eruptions is best explained by a subsequent expansion of sea ice and a related weakening of Atlantic currents, according to computer simulations conducted for the study.

The study, which used analyses of patterns of dead vegetation, ice and sediment core data, and powerful computer climate models, provides new evidence in a longstanding scientific debate over the onset of the Little Ice Age. Scientists have theorized that the Little Ice Age was caused by decreased summer solar radiation, erupting volcanoes that cooled the planet by ejecting sulfates and other aerosol particles that reflected sunlight back into space, or a combination of the two.

"This is the first time anyone has clearly identified the specific onset of the cold times marking the start of the Little Ice Age," says lead author Gifford Miller of the University of Colorado Boulder. "We also have provided an understandable climate feedback system that explains how this cold period could be sustained for a long period of time. If the climate system is hit again and again by cold conditions over a relatively short period -- in this case, from volcanic eruptions -- there appears to be a cumulative cooling effect."

"Our simulations showed that the volcanic eruptions may have had a profound cooling effect," says NCAR scientist Bette Otto-Bliesner, a co-author of the study. "The eruptions could have triggered a chain reaction, affecting sea ice and ocean currents in a way that lowered temperatures for centuries."

The study appears this week in Geophysical Research Letters. The research team includes co-authors from the University of Iceland, the University of California Irvine, and the University of Edinburgh in Scotland. The study was funded in part by the National Science Foundation, NCAR's sponsor, and the Icelandic Science Foundation.

The article goes on for a bit more. If they are right, then it just goes to show you can't discount the power of volcanoes on our environment.




- Ernie.

BTW here is a video critical of the peer review process that plagues modern climate science.

[RnR]

The CSIRO State of the Climate 2012 have been released - http://www.csiro.au/en/Outcomes/Clim...mate-2012.aspx

[RnR]

In the first study of its kind in Australasia, scientists have used 27 natural climate records to create the first large-scale temperature reconstruction for the region over the last 1000 years.

...

Lead researcher, Dr Joelle Gergis from the University of Melbourne said the results show that there are no other warm periods in the last 1000 years that match the warming experienced in Australasia since 1950.

"Our study revealed that recent warming in a 1000 year context is highly unusual and cannot be explained by natural factors alone, suggesting a strong influence of human-caused climate change in the Australasian region," she said.

http://www.sciencedaily.com/releases...0517111431.htm

[Airquarious]

UC Riverside-led team identifies black carbon and tropospheric ozone as most likely drivers of large-scale atmospheric circulation change in the Northern hemisphere tropics

http://wattsupwiththat.com/2012/05/1...o2/#more-63721

[ernie]

http://www.nasa.gov/topics/earth/fea...land-melt.html

For several days this month, Greenland's surface ice cover melted over a larger area than at any time in more than 30 years of satellite observations. Nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its two-mile-thick center, experienced some degree of melting at its surface, according to measurements from three independent satellites analyzed by NASA and university scientists.

On average in the summer, about half of the surface of Greenland's ice sheet naturally melts. At high elevations, most of that melt water quickly refreezes in place. Near the coast, some of the melt water is retained by the ice sheet and the rest is lost to the ocean. But this year the extent of ice melting at or near the surface jumped dramatically. According to satellite data, an estimated 97 percent of the ice sheet surface thawed at some point in mid-July.

Researchers have not yet determined whether this extensive melt event will affect the overall volume of ice loss this summer and contribute to sea level rise.

"The Greenland ice sheet is a vast area with a varied history of change. This event, combined with other natural but uncommon phenomena, such as the large calving event last week on Petermann Glacier, are part of a complex story," said Tom Wagner, NASA's cryosphere program manager in Washington. "Satellite observations are helping us understand how events like these may relate to one another as well as to the broader climate system."

This type of cycle happens on average every 150 years or so.


- Ernie.

[RnR]

Originally Posted by ernie

This type of cycle happens on average every 150 years or so.

Yup - just a natural cycle which is at its peak of its warming potential right now. World temps will steadily get colder from here on.

[Tinian]

Originally Posted by RnR

Yup - just a natural cycle which is at its peak of its warming potential right now. World temps will steadily get colder from here on.

How many people would be willing to put their money on the satellite data showing a clear trend in that direction for the next 5-10 years?

[RnR]

Originally Posted by Tinian

How many people would be willing to put their money on the satellite data showing a clear trend in that direction for the next 5-10 years?

Zero from what I understand - I was being sarcastic in my reply to ernie

AN Australian Antarctic scientist has made a climate studies breakthrough by examining how the earth warmed up after the last Ice Age.

Glaciologist Joel Pedro, from the Antarctic Climate and Ecosystems Cooperative Research Centre, is part of an international team that has worked out how quickly carbon entered the atmosphere as a result of temperature rises beginning around 19,000 years ago.

The team discovered that CO2 increased naturally in the atmosphere much more quickly than previously thought during an 8000-year period of global warming.
...

The finding suggests "feedback" in the climate system - where temperature increases CO2, which in turn increases temperature - happens faster than expected.

...

Dr Pedro says the study of natural warming only underlines the speed at which human-created climate change has occurred.

He says 8000 years' worth of natural CO2 increases have been created in the 200 years since the industrial revolution.

"Just as the steady increase in CO2 helped to melt the ice caps and warm the earth out of the ice age, the rapid increase now in CO2 is also driving up temperatures, only at a much faster rate," he said.

"What we're doing now is over a hundred times faster."

http://www.news.com.au/technology/sc...-1226434145677

Original press release: http://www.acecrc.org.au/access/cms/...=122&full=true

Edit: Just came across this...

A record heat wave, drought and catastrophic wildfires are accomplishing what climate scientists could not: convincing a wide swath of Americans that global temperatures are rising.

In the four months since March there has been a jump in U.S. citizens’ belief that climate change is taking place, especially among independent voters and those in southern states such as Texas, which is now in its second year of record drought, according to nationwide polls by the University of Texas.

In a poll taken July 12-16, 70 percent of respondents said they think the climate is changing...

http://www.businessweek.com/news/201...-to-70-percent

Humans are weird :/

[ernie]

The Antarctic survey by Pedro et al, that found CO2 only lagged temperature by 400 years, not 1,000 years a is commonly presented. 400 years is a mighty long time. If it were 4 years I might pay more attention to the argument.

The Greenland ice melt as estimated from the Oceansat-2 data is really just food for the alarmists, after all it's the middle of summer there. The Greenland ice sheet has an average thickness of over 2km. Do you know how much energy it would take to melt that! Lots. Go get a cubic meter of ice and stick it out in the sun at near zero temperatures and see how long it takes to melt, and then make it 2,000 times thicker and try again.


- Ernie.

[Lucifers Mentor]

Originally Posted by RnR

Yup - just a natural cycle which is at its peak of its warming potential right now. World temps will steadily get colder from here on.

Care to show this? Especially in light of the recorded correlations between CO2 and temperature change?

Edit: Missed your context wrt ernie.

Originally Posted by ernie

The Antarctic survey by Pedro et al, that found CO2 only lagged temperature by 400 years, not 1,000 years a is commonly presented. 400 years is a mighty long time. If it were 4 years I might pay more attention to the argument.

Pedro's paper says nothing about climate change. The climate system is highly nonlinear, and the responses to short term increases in CO2 (due to volcanic activity) aren't expected to have the same effect as long term, sustained high level emissions - to argue otherwise is disingenuous.

Originally Posted by Pedro

The coupled rise in temperature and natural increase in carbon dioxide that helped end the ice age took place gradually, over about 8000 years. What we have seen since the start of the industrial revolution is a similar carbon dioxide increase occurring over only a few hundred years. This is way faster than anything in the ice core record and it’s clearly human-caused. Just as the steady increase in carbon dioxide helped to melt the ice caps and warm the Earth out of the ice age, the rapid increase now in carbon dioxide is also driving up temperatures, only at a much faster rate.

http://www.sciencealert.com.au/news/20122407-23600.html

Originally Posted by RnR

Edit: Just came across this...

http://www.businessweek.com/news/201...-to-70-percent

Humans are weird :/

This has, already been discussed (erroneously, as the discussion should have occurred here) in P&P's thread on the carbon tax last week - an increased frequency of extreme events is a prediction of climate change. Individual events cannot be coupled with climate change, but the probability of their occurring has increased. It's not humans confusing correlation with causation, the likelihood of extreme weather events are attributable to climate change.

Originally Posted by Tinian

How many people would be willing to put their money on the satellite data showing a clear trend in that direction for the next 5-10 years?

Disingenuous question - what is a "clear tread"? Sounds like the claim put forward by young earth creationists, that they will give anyone $1 million dollars if they can provide proof of evolution. Of course, their standards of proof are so warped that it is impossible to satisfy their criteria. There has been a clear trend since the 1950's, what more do you want? The climate system is a highly complex, highly nonlinear system subject to variation through both natural (ENSO, as an example, plays a huge role in short-scale climate dynamics) and human processes (everything from changes in land coverage, to emissions).

Edit: Missed you were talking about a cooling trend, not a warming one, my mistake.

Originally Posted by ernie

The article goes on for a bit more. If they are right, then it just goes to show you can't discount the power of volcanoes on our environment.

....then....it's....a good thing that they haven't been discounted? Their effect is well known. Plus, your link says ""The eruptions could have triggered a chain reaction, affecting sea ice and ocean currents in a way that lowered temperatures for centuries." - which would seem to run contrary to your point that we should be paying more attention to the warming effect elicited by volcanic eruptions.

Originally Posted by ernie

BTW here is a video critical of the peer review process that plagues modern climate science.

movie

Care to provide some actual evidence of some big peer review conspiracy? Peer review is not a perfect process, but it works pretty damn well.

[Fortigurn]

Climate change skeptic turns 180 degrees; after rejecting the scientific evidence for Anthropogenic Global Warming, he now accepts it as a result of the study he himself led.

THE earth's land has warmed by 1.5 degrees Celsius in the past 250 years and "humans are almost entirely the cause", according to a scientific study set up to address climate sceptic concerns about whether human-induced global warming is occurring.

Richard Muller, a climate sceptic physicist who founded the Berkeley Earth Surface Temperature (BEST) project, said he was "surprised" by the findings. "We were not expecting this, but as scientists, it is our duty to let the evidence change our minds."

[shon982]

[Walshy]

Originally Posted by ernie

http://www.nasa.gov/topics/earth/fea...land-melt.html

This type of cycle happens on average every 150 years or so.

Actually, no, it doesn't. It last happened 150 years ago. The one before that was around the year 1100 or something like that, and it's only happened 4-5 times in the last 2,000 years.

It has occurred every 150 years if you average it over the past 10,000 years, which just happens to count a whole cluster of them back around 6,000-8,000 years ago, during the Holocene Climate Optimum at the end of the last ice age.

Then again - you also need to consider that these melt events recorded in the ice core may be local, and not widespread like the current melting. More ice cores needed to see if it was widespread across all of Greenland.

[ernie]

Anyone noticed the record low Arctic sea ice extent being set atm?

http://www.ijis.iarc.uaf.edu/en/home...xtent_prev.htm

Been a hot summer this year in the northern hemisphere, right up there with 1936.

Unfortunately, the satellite records for sea ice don't' go back that far to compare.


- Ernie.