New Research

[knocker]

How could melting ice thousands of miles away possibly affect you? A recent study published in Nature Geoscience provides one answer to that question. Mark Flanner at the University of Michigan and his collaborators used satellite data to measure how much changes in snow and ice in the Northern Hemisphere have contributed to rising temperatures in the last 30 years. The loss of snow and ice warmed the planet more than models predicted it would.

Snow and ice help control how much of the Sun’s energy Earth soaks up. Bright white snow and ice reflect energy back to space. Because that energy does not get absorbed, it does not go into Earth’s climate. As a result, snow and ice cool the planet. This effect is called a climate forcing because snow and ice directly influence the climate.

The left image shows how much energy the Northern Hemisphere’s snow and ice—called the cryosphere—reflected on average between 1979 and 2008. Dark blue indicates more reflected energy, and thus more cooling. The Greenland ice sheet reflects more energy than any other single location in the Northern Hemisphere. The second-largest contributor to cooling is the cap of sea ice over the Arctic Ocean.

The right image shows how the energy being reflected from the cryosphere has changed between 1979 and 2008. When snow and ice disappear, they are replaced by dark land or ocean, both of which absorb energy. The image shows that the Northern Hemisphere is absorbing more energy, particularly along the outer edges of the Arctic Ocean, where sea ice has disappeared, and in the mountains of Central Asia.

“On average, the Northern Hemisphere now absorbs about 100 PetaWatts more solar energy because of changes in snow and ice cover,†says Flanner. “To put it in perspective, 100 PetaWatts is seven-fold greater than all the energy humans use in a year.†Changes in the extent and timing of snow cover account for about half of the change, while melting sea ice accounts for the other half.

Flanner and his colleagues made both calculations by compiling field measurements and satellite observations from the Moderate Resolution Imaging Spectroradiometer (MODIS), Advanced Very High Resolution Radiometer, and Nimbus-7 and DMSP SSM/I passive microwave data. The analysis is the first calculation of how much the energy the entire cryosphere reflects. It is also the first observation of changes in reflected energy because of changes in the entire cryosphere.

http://earthobservat...ew.php?id=49440

Image by Rob Simmon, made with data provided by Mark Flanner, University of Michigan. Caption by Holli Riebeek.

Edited February 24, 2011 by weather ship

[knocker]

Interesting.

"It's not that the warm Gulf Stream waters substantially heat up Europe," Kaspi says. "But the existence of the Gulf Stream near the U.S. coast is causing the cooling of the northeastern United States."

http://www.eurekalert.org/pub_releases/2011-03/ciot-wwc032911.php

[Gray-Wolf]

Interesting.

"It's not that the warm Gulf Stream waters substantially heat up Europe," Kaspi says. "But the existence of the Gulf Stream near the U.S. coast is causing the cooling of the northeastern United States."

http://www.eurekaler...t-wwc032911.php

So not as prone to 'shutdown' as we might have been lead to believe?

[knocker]

So not as prone to 'shutdown' as we might have been lead to believe?

Quite. To paraphrase Mark Twain, I believe the reports of it's demise to be somewhat premature.

[songster]

Eh, what does that paper have to do with shutdown or otherwise of the Gulf Stream? It's pointing out a newly-discovered mechanism for how the Gulf Stream affects weather and heat transport, but says bugger all about what drives it and how that might change under one set of conditions or another. The principle applies generally to any warm current or warm water region off the east coast of any continent.

[Gray-Wolf]

I think you're skirting the broader issue of warm water on atmospheric circulation patterns?

If we can see what 'warm plumes' (from warm water) can drive in the atmosphere, and so weather patterns, we must accept the changes that we are now seeing across areas of the Arctic Ocean come Autumn/Early winter and the changes this must drive in atmospheric circulation? (or is it just the Atlantic/Pacific basins that have this 'water warmer than air' setups?)

We are also shown how the 'prevailing winds' help drive/position the Gulf stream so once a 'pattern is established' across the Arctic basin where will the new prevailing winds 'push' surface currents and how will that impact our 'stable' climates (stable enough to have all the major grain/cereal producing areas where they lie today!)?

Set that against the promise of a warming globe and we find ourselves in a right pickle in no time at all!

[Cloudman]

The rate of sea-level rise is rapidly increasing suggesting that the IPCC may have underestimated sea-level rise by the end of the century

Nature Reports Climate Change

Published online: 6 April 2010 | doi:10.1038/climate.2010.29

A new view on sea level rise

Stefan Rahmstorf

Over the course of the twentieth century, the rate of sea level rise has roughly tripled in response to 0.8 °C global warming². Since the beginning of satellite measurements, sea level has risen about 80 per cent faster, at 3.4 millimetres per year³, than the average IPCC model projection of 1.9 millimetres per year.

from

http://www.nature.com/climate/2010/1004/full/climate.2010.29.html

[Gray-Wolf]

The rate of sea-level rise is rapidly increasing suggesting that the IPCC may have underestimated sea-level rise by the end of the century

Nature Reports Climate Change

Published online: 6 April 2010 | doi:10.1038/climate.2010.29

A new view on sea level rise

Stefan Rahmstorf

Over the course of the twentieth century, the rate of sea level rise has roughly tripled in response to 0.8 °C global warming². Since the beginning of satellite measurements, sea level has risen about 80 per cent faster, at 3.4 millimetres per year³, than the average IPCC model projection of 1.9 millimetres per year.

from

http://www.nature.co...te.2010.29.html

When you look at Greenland over the past 8years you can see how inadequate some of the more 'linear' projections for sea level rise are. Just the Peterman calve last year highlights this with the 'ice front' pulled back a number of km and basal inertia reduced by that amount. With the weight of the ice sheet bearing down on it (and the Fjord now hastening up the valley) only a rapid and extreme cool down can hope to halt the 'natural' forces at play. I expect a smaller calve from the same Glacier this year so it's retreat ,back towards the ice sheet, looks set to continue.

The amount of open water , come summers end ,around the remaining ice sheets across the Arctic is also hastening their demise with Devonshire Island looking quite precarious.

With the sheets gone than 'dark land' is exposed each summer further accelerating the process in the Basin and into Greenland.

[Iceberg]

Probably the best article I've seen concerning the Berkeley report into global temperatures.

http://www.economist.com/blogs/babbage/2011/03/climate_change

For those not following it a team of largely skeptical scientists from a skeptical institution, partly funded by a skeptical group has found that Global temperatures have been rising pretty much inline with the Major datasets of Hadley et al and fully in line with IPCC predictions.

They further find that despite Watts best attemps to discredit the US temperature record due to incorrectly situated recording stations there was actually very little difference in the trend between his "incorrect sites" and his correct sites. Any difference that does exist seems to actually be the other way round i.e watts incorrect sites were actually cooler than the general trend and so the US might have a more pronounced warming trend than officially shown if watts were correct.

Watts who first claimed at the start of March.

"I’m prepared to accept whatever result they produce, even if it proves my premise wrong. I’m taking this bold step because the method has promise. So let’s not pay attention to the little yippers who want to tear it down before they even see the results. I haven’t seen the global result, nobody has, not even the home team, but the method isn’t the madness that we’ve seen from NOAA, NCDC, GISS, and CRU, and, there aren’t any monetary strings attached to the result that I can tell. If the project was terminated tomorrow, nobody loses jobs, no large government programs get shut down, and no dependent programs crash either. That lack of strings attached to funding, plus the broad mix of people involved especially those who have previous experience in handling large data sets gives me greater confidence in the result being closer to a bona fide ground truth than anything we’ve seen yet."

Watts is now saying that they haven't done a very good job and that it's been rushed.

Mr Watts pull the other one it's got bells on......There is not a single global dataset or method which does not show the warming.Unfortunately.

Edited April 1, 2011 by Iceberg

[pottyprof]

Probably the best article I've seen concerning the Berkeley report into global temperatures.

http://www.economist.com/blogs/babbage/2011/03/climate_change

Watts is now saying that they haven't done a very good job and that it's been rushed.

Mr Watts pull the other one it's got bells on......There is not a single global dataset or method which does not show the warming.Unfortunately.

Have to agree with you. It's been entertaining. I agree with the idea that data is worth looking over to clear out the doubt but I think it's been clear for long enough that we've been warming. Still the old chestnut of how much is natural and how much is anthropogenic to sort out though......

[keithlucky]

When you look at Greenland over the past 8years you can see how inadequate some of the more 'linear' projections for sea level rise are. Just the Peterman calve last year highlights this with the 'ice front' pulled back a number of km and basal inertia reduced by that amount. With the weight of the ice sheet bearing down on it (and the Fjord now hastening up the valley) only a rapid and extreme cool down can hope to halt the 'natural' forces at play. I expect a smaller calve from the same Glacier this year so it's retreat ,back towards the ice sheet, looks set to continue.

The amount of open water , come summers end ,around the remaining ice sheets across the Arctic is also hastening their demise with Devonshire Island looking quite precarious.

With the sheets gone than 'dark land' is exposed each summer further accelerating the process in the Basin and into Greenland.

Depends which report you read sea ice has increased this year Total sea ice extent on the northern hemisphere since 2005. The ice extent values are calculated from the ice type data from the Ocean and Sea Ice, Satellite Application Facility (OSISAF), where areas with ice concentration higher than 30% are classified as ice.

The total area of sea ice is the sum of First Year Ice (FYI), Multi Year Ice (MYI) and the area of ambiguous ice types, from the OSISAF ice type product. However, the total estimated ice area is underestimated due to unclassified coastal regions where mixed land/sea pixels confuse the applied ice type algorithm. The shown sea ice extent values are therefore recommended be used qualitatively in relation to ice extent values from other years shown in the figure. In 2011 sea ice climatology and anomaly data will be available here.

Sea ice extent for the past 5 years (in million km2) for the northern hemisphere, as a

function of date.

[Gray-Wolf]

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VHB-52BWW4J-1&_user=10&_coverDate=03/10/2011&_rdoc=1&_fmt=high&_orig=gateway&_origin=gateway&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=1cc8c101b33bbd6ec3425f16b658b472&searchtype=a

Another paper showing how small an influence Cosmic Rays have on climate change.

[johnholmes]

I'm not sure just which thread to post this in so admin/mods please move if you thin another thread is more appropriate.

link to ozone depletion in the Arctic-I'd rather not it be in the Arctic Ice thread as that does semm to generate a lot of heated comments. This is a pretty factual report from WMO.

http://www.bbc.co.uk/news/science-environment-12969167

[knocker]

Rapid warming in the Arctic is creating a new and fast-growing pool of fresh water in the Arctic Ocean. Measuring at least 7500 cubic kilometres, it could flush into the Atlantic Ocean and slow the Gulf Stream, bringing colder winters to Europe.

The water is mostly coming from melting permafrost and rising rainfall, which is increasing flows in Siberian rivers that drain into the Arctic, such as the Ob and Yenisei. More comes from melting sea ice, says Laura de Steur of the Royal Netherlands Institute of Sea Research in 't Horntje, who is tracking the build-up.

http://www.newscientist.com/article/dn20338-gulf-stream-could-be-threatened-by-arctic-flush.html

[VillagePlank]

Probably the best article I've seen concerning the Berkeley report into global temperatures.

http://www.economist.com/blogs/babbage/2011/03/climate_change

For those not following it a team of largely skeptical scientists from a skeptical institution, partly funded by a skeptical group has found that Global temperatures have been rising pretty much inline with the Major datasets of Hadley et al and fully in line with IPCC predictions.

I've been following this closely.

And it's a red-herring. For a start, can you name one person - seriously, one person - who has legitimate concerns about the temperature record? The reason why I have been interested in this is because it supposedly completely open (haven't seen any source-code, nor handy csv files, yet!) But back to the point: name one person who thinks it's not warmer now than 30 years ago? Please. Please!

I suspect that you'd find it difficult. I think that it's nigh on impossible.

So where does this leave us, then? As a sceptic for the causes of that warming, I am NOT - I repeat NOT - going to defend a position I don't hold - and serious integrity questions need to be asked about anyone who wants to band such strawman positions about.

(EDIT: Sorry! Trying to keep out of all this, now - but just couldn't let that one go)

Edited April 7, 2011 by VillagePlank

[Iceberg]

Simple VP trying looking at Watts, who has spent the last several years saying that global warming is nowhere near the levels as exposed by the HAD/GISS etc.(it's on his site if you want to see). He's ran a crusade against it with the help of other varous AGW sceptics.

This isn't a red herring or why would koch etc have put the money up.....

PS nobody has asked you to defend it.......But maybe we can stop some of the more sillier arguements on these threads about whether the warming is in the trend line of the IPCC predictions etc..

Sorry another PS, but to add

"But back to the point: name one person who thinks it's not warmer now than 30 years ago? Please. Please!"

This is more of a strawman than anything I've seen for ages, this has nothing to do with whether it was warmer or not than 30 years ago. But to do with temperature trends. it's the scale of the trends which are disputed and which has unexpectedly been backed up by this study.

IF the warming is on the scale shown in the global temperature datasets above then it becomes much more difficult to subscribe to natural cycles or cooling IMO

Edited April 7, 2011 by Iceberg

[jethro]

I'm not sure your last sentence holds true Iceberg.

This Berkeley thing, although interesting from a "silence the critics" perspective, is laudable and they should be congratulated for trying to decipher/verify the temperature data; it does nothing to address the issue of cause. Nor does it address past warming events.

IMO this is more like calling the auditors in to check company accounts, a worthwhile exercise but revealing no more than whether or not the accountants are competent.

[VillagePlank]

But maybe we can stop some of the more sillier arguements on these threads

Agreed.

[Iceberg]

I'm not sure your last sentence holds true Iceberg.

This Berkeley thing, although interesting from a "silence the critics" perspective, is laudable and they should be congratulated for trying to decipher/verify the temperature data; it does nothing to address the issue of cause. Nor does it address past warming events.

IMO this is more like calling the auditors in to check company accounts, a worthwhile exercise but revealing no more than whether or not the accountants are competent.

I think it does hold true as one of the arguements against AGW/ACC is that the warming we have now is natural and has occured in the last 100 years before(check out Monckton etc). There if it has occured recently then it can be more easily explained by natural drivers.

I agree with the auditing comment but only with the caveat that you need to add 1000's of people, websites blogs etc saying that the company is upto dozens of illegal activities.

[Gray-Wolf]

http://www.sciencedaily.com/releases/2011/04/110406161039.htm

Well who'd have thunk it? The thicker you are (and poorer) the more likely you are to judge climate change on the temp/weather where you are at that moment???? I thought some of the blogs fell silent when we moved away from snowstorm season and into drought/heatwave season.........

[VillagePlank]

"But back to the point: name one person who thinks it's not warmer now than 30 years ago? Please. Please!"

This is more of a strawman than anything I've seen for ages, this has nothing to do with whether it was warmer or not than 30 years ago. But to do with temperature trends. it's the scale of the trends which are disputed and which has unexpectedly been backed up by this study.

OMG!

A (linear) trend is of the form y=mx+c.

We have two points (x1,y1) and (x2,y2) where x=time, y=magnitude, the suffix 1 is first time, and the suffix 2 is last time - ie 30 years ago, and now, respectively.

Therefore,

m = (y2-y1)/(x2-x1)

c = y1-(m*x1)

We therfore have the equation of a line ie y=mx+c. More precisely we can approximate magnitude as a function of time. That is also known as a trend

Walkthrough:

Here we have x1=1970AD, y1 = 10degC, x2=2000AD, y2=12degC. The gradient, m, is the trend, in this case 0.06degC per unit x, or year, if you prefer.

There is no strawman here, and, to be honest, I am mildly offended that you chose to write that since the mathematics that shows my comment isn't a strawman isn't exactly difficult.

Edited April 7, 2011 by VillagePlank

[Iceberg]

There is a term called obfuscation......

Quite simply this study isn't about whether it's 0.1C warmer now than 30 years ago. It's about auditing the current global temperature records.

[VillagePlank]

There is a term called obfuscation......

Quite simply this study isn't about whether it's 0.1C warmer now than 30 years ago. It's about auditing the current global temperature records.

I must have misunderstood '... to do with temperature trends. it's the scale of the trends which are disputed ...'

I am, however, completely baffled that that means ' ...about auditing the current global temperature records.'

Feels obfuscated to me, I agree.

Edited April 7, 2011 by VillagePlank

[Iceberg]

I can't be explaining it that badly VP.

The task they undertook was to audit/confirm the temperature trends/datasets of the global temperature sets such as HADCRU.

I say again it was not to see whether we were slightly higher than 30 years ago.

You can put whatever maths you like but it doesn't alter this fact, therefore your arguement about it being a strawman is very wrong.

[VillagePlank]

I can't be explaining it that badly VP.

The task they undertook was to audit/confirm the temperature trends/datasets of the global temperature sets such as HADCRU.

I say again it was not to see whether we were slightly higher than 30 years ago.

You can put whatever maths you like but it doesn't alter this fact, therefore your arguement about it being a strawman is very wrong.

I give up. Really.