New Research

[knocker]

Unprecedented glacier melting in the Andes blamed on climate change

Glaciers in the tropical Andes have been retreating at increasing rate since the 1970s, scientists write in the most comprehensive review to date of Andean glacier observations. The researchers blame the melting on rising temperatures as the region has warmed about 0.7°C over the past 50 years (1950-1994). This unprecedented retreat could affect water supply to Andean populations in the near future. These conclusions are published today in The Cryosphere, an Open Access journal of the European Geosciences Union (EGU).

The international team of scientists – uniting researchers from Europe, South America and the US – shows in the new paper that, since the 1970s, glaciers in tropical Andes have been melting at a rate unprecedented in the past 300 years. Globally, glaciers have been retreating at a moderate pace as the planet warmed after the peak of the Little Ice Age, a cold period lasting from the 16th to the mid-19th century. Over the past few decades, however, the rate of melting has increased steeply in the tropical Andes. Glaciers in the mountain range have shrunk by an average of 30-50% since the 1970s, according to Antoine Rabatel, researcher at the Laboratory for Glaciology and Environmental Geophysics in Grenoble, France, and lead author of the study.

Glaciers are retreating everywhere in the tropical Andes, but the melting is more pronounced for small glaciers at low altitudes, the authors report. Glaciers at altitudes below 5,400 metres have lost about 1.35 metres in ice thickness (an average of 1.2 metres of water equivalent [see note]) per year since the late 1970s, twice the rate of the larger, high-altitude glaciers.

"Because the maximum thickness of these small, low-altitude glaciers rarely exceeds 40 metres, with such an annual loss they will probably completely disappear within the coming decades," says Rabatel.

http://www.eurekalert.org/pub_releases/2013-01/egu-ugm012113.php

[knocker]

Global warming less extreme than feared?

Policymakers are attempting to contain global warming at less than 2°C. New estimates from a Norwegian project on climate calculations indicate this target may be more attainable than many experts have feared.

Internationally renowned climate researcher Caroline Leck of Stockholm University has evaluated the Norwegian project and is enthusiastic.

“These results are truly sensational,†says Dr Leck. “If confirmed by other studies, this could have far-reaching impacts on efforts to achieve the political targets for climate.â€

http://www.forskningsradet.no/en/Newsarticle/Global_warming_less_extreme_than_feared/1253983344535/p1177315753918

[knocker]

Cyclone did not cause 2012 record low for Arctic sea ice

It came out of Siberia, swirling winds over an area that covered almost the entire Arctic basin in the normally calm late summer. It came to be known as "The Great Arctic Cyclone of August 2012," and for some observers it suggested that the historic sea ice minimum may have been caused by a freak summer storm, rather than warming temperatures.

But new results from the University of Washington show that the August cyclone was not responsible for last year's record low for Arctic sea ice. The study was published online this week in Geophysical Research Letters. "The effect is huge in the immediate aftermath of the cyclone, but after about two weeks the effect gets smaller," said lead author Jinlun Zhang, an oceanographer in the UW's Applied Physics Laboratory. "By September, most of the ice that melted would have melted with or without the cyclone."

Recent research showed that the Arctic cyclone was the most powerful ever seen during the month of August, and the 13th most powerful of all Arctic storms in more than three decades of satellite records.

"The storm was enormous," said co-author Axel Schweiger, a polar scientist in the Applied Physics Laboratory. "The impact on the ice was immediately obvious, but the question was whether the ice that went away during the storm would have melted anyway because it was thin to begin with."

The UW team performed the climate scientist's equivalent of a forensic exam: They ran a computer simulation of last summer's weather and compared it against a second scenario that was identical except that there was no cyclone.

Results showed the storm caused the sea ice to pass the previous record 10 days earlier in August than it would have otherwise, but only reduced the final September ice extent by 150,000 square kilometers (almost 60,000 square miles), less than a 5 percent difference. By comparison, the actual minimum ice extent was 18 percent less than the previous record set in 2007.

The study also revealed a surprising mechanism for the cyclone-related melting. Earlier discussions about the cyclone's effect had focused on winds breaking up the ice or driving ice floes into areas of warmer water. The results suggest that neither process led to much increase in melting.

http://www.eurekalert.org/pub_releases/2013-01/uow-cdn013113.php

[knocker]

Don't know whether this been posted before

Reconstructed changes in Arctic sea ice over the past 1,450 years

Abstract

Arctic sea ice extent is now more than two million square kilometres less than it was in the late twentieth century, with important consequences for the climate, the ocean and traditional lifestyles in the Arctic^{1, 2}. Although observations show a more or less continuous decline for the past four or five decades^{3, 4}, there are few long-term records with which to assess natural sea ice variability. Until now, the question of whether or not current trends are potentially anomalous⁵ has therefore remained unanswerable. Here we use a network of high-resolution terrestrial proxies from the circum-Arctic region to reconstruct past extents of summer sea ice, and show that—although extensive uncertainties remain, especially before the sixteenth century—both the duration and magnitude of the current decline in sea ice seem to be unprecedented for the past 1,450 years. Enhanced advection of warm Atlantic water to the Arctic⁶ seems to be the main factor driving the decline of sea ice extent on multidecadal timescales, and may result from nonlinear feedbacks between sea ice and the Atlantic meridional overturning circulation. These results reinforce the assertion that sea ice is an active component of Arctic climate variability and that the recent decrease in summer Arctic sea ice is consistent with anthropogenically forced warming.

http://www.nature.com/nature/journal/v479/n7374/full/nature10581.html

Solid red line is the reconstructed 40 year smoothed, late-summer Arctic sea ice extent from . Shaded area shows 95% confidence interval. Blue dashed line shows modern observations.

http://www.skepticalscience.com/graphics.php?g=48

[knocker]

Volcano location could be greenhouse-icehouse key

Study: Episodic purging of 'carbonate capacitor' drives long-term climate cycle

HOUSTON -- (Feb. 6, 2013) -- A new Rice University-led study finds the real estate mantra "location, location, location" may also explain one of Earth's enduring climate mysteries. The study suggests that Earth's repeated flip-flopping between greenhouse and icehouse states over the past 500 million years may have been driven by the episodic flare-up of volcanoes at key locations where enormous amounts of carbon dioxide are poised for release into the atmosphere.

"We found that Earth's continents serve as enormous 'carbonate capacitors,'" said Rice's Cin-Ty Lee, the lead author of the study in this month's GeoSphere. "Continents store massive amounts of carbon dioxide in sedimentary carbonates like limestone and marble, and it appears that these reservoirs are tapped from time to time by volcanoes, which release large amounts of carbon dioxide into the atmosphere."

http://www.eurekalert.org/pub_releases/2013-02/ru-vlc020613.php

[Gray-Wolf]

Like the PETM and the earth changes ongoing then?

This is why I find it difficult to get into the mindset of folks that pooh,pooh GHG's as a lead forcing no matter what 'solar' is doing at that time. This time we have been the mechanism to flood the atmosphere with GHG's so why would we not expect it to act in the same way as when nature floods the atmosphere with GHG's?

There is no questioning our releases and there is no questioning past results from such releases so where is the beef (apart from oil money propaganda swaying the more gullible/frightened minds?).

[knocker]

Very true GW. If the billions of tons of CO2 added to the atmosphere in the recent past had been down to increased volcanic activity, and there was no AGW involvement, the discussion would be about what policies should we adopt to mitigate the natural variations in climate. Ergo, AGW equates to increased volcanic activity over the last 150 years,

[Gray-Wolf]

I know I'm a broken record here but I'm asking for input to show I'm wrong in my concerns?

We have just sat through the game changer.

Up unto the start of the noughties AGW forcings had been pretty well pegged by our natural climate inertia. The oceans have just gobbled up most of the increase in 'saved energy' from the increased capacity for holding heat within the atmosphere but some of that 'increase' went into ice melt.

In the noughties Arctic ice was thin enough to see large amounts melt out reducing our albedo and increasing our absorption (snow melt ever earlier lead this dance).

We are now seeing impacts from all this energy let loose in the climate system.

This new phase worries me as it illustrates that climate inertia is being overcome and new energy (above and beyond GHG forcing) is now affecting our climate system. This will be far from slow moving. Because the climate inertia was buckling this 'pulse' of energy will rush in other swift impacts as we rapidly 'flip' to a higher energy climate setting.

My worries see this as a decadal scale change....... no more room for doubts, just rapid and extreme change.

Can someone please show me why this is not going to be so?.

[Gray-Wolf]

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00492.1

This new paper doesn't paint a good picture for the Arctic? The sudden onset of convective clouds over the basin does not sound good?

I remember , back in the old 'slow watch' days, wondering the impacts of home grown Arctic storms rolling south into Eurasia, seems it is not just a fantasy anymore but an awaited outcome?

[BornFromTheVoid]

http://journals.amet...LI-D-12-00492.1

This new paper doesn't paint a good picture for the Arctic? The sudden onset of convective clouds over the basin does not sound good?

I remember , back in the old 'slow watch' days, wondering the impacts of home grown Arctic storms rolling south into Eurasia, seems it is not just a fantasy anymore but an awaited outcome?

Very interesting study but played out over thousands of years, as opposed to the rapid increase in CO2 and (relatively) rapid temperature increase we're seeing now.

Some points of note:

It suggests a strengthening of the Arctic halocline in response to increased CO2, and a reduction in warm water upwelling.

Considering it's not taking into account methane, black carbon and other sources that contribute to melt (as well as how much models overestimate sea ice cover in general) it requires just 490ppm CO2 for ice free summers, and 780ppm CO2 for the Arctic to be ice free all year round. It does require quite a degree of warming to produce the ice free winters though, 8C.

Antarctic sea ice is much more stable than Arctic sea ice, but also takes much longer to recover once CO2 and temperatures begin to decline (when coming down the a very high CO2 and warm global state).

[Gray-Wolf]

I wonder at what temp we can expect ocean evaporation from the surface of the Arctic ocean to take place? The 'odd' temps at the McKenzie delta last year would have been near enough to sustain a Hurricane!!???

Should we expect a far more humid (and so heat retentice) atmosphere to develop over the ice free waters each summer and will this impact re-freeze by retaining heat above the warmed ocean longer into the autumn?

The other thing modelled was the swicth to ice free winters and this seemed to have an initial abrupt shift to less ice. It linked this with the appearance of convective clouds (and the latent heat released as they form). We already see Arctic sea smoke above new leads through winter so is it just an intensification of this that will suddenly flip the switch to cloud formation?

When you look at what can build above a cooling tower ,given the right conditions, I have to wonder how much further we need travel from where we are today for that 'heat source' to be great enough to cause free rise of that moist air into the higher atmosphere?

[BornFromTheVoid]

The study suggests that ice free summers stretch from July to November before the abrupt switch to ice free winters, and that Northern Hemisphere temperatures had to increase by 8C before the strong convection kicked in to cause ice free winters.

On the model, they increase the rate of CO2 concentration by less than 0.5ppm per year, so it's not directly comparable to our current situation.

[Gray-Wolf]

I got that from the paper BFTW but then it does pose some interesting 'timelines' for change? If i'm taking it in correctly the impacts on winter ice occur whilst summer change is still ongoing?

I know i shouldn't but i take it 'ice free' is a given and so am now trying to understand how we will see that period extend into the year and , obviously, poor winter ice is a part of this?

A.t.m. we see a thinning of the ice as the last of the multiyear is dealt with so maybe the winter changes can only occur once we have reduced perenial to a certain level?

[songster]

I wonder at what temp we can expect ocean evaporation from the surface of the Arctic ocean to take place? The 'odd' temps at the McKenzie delta last year would have been near enough to sustain a Hurricane!!???

You mean the obvious error that was present in one model but no others, and vanished as soon as I emailed the guy in charge of the page to ask what was up?

[Gray-Wolf]

I'm sorry Songster but the elevated temps to the side of the Delta were present all through the second half of summer and into the winter across a number of sites?

The crazy temps didn't last long but a partial 'bulls eye' of temps well above the basin's average did. The warming of the north slope (and it's run off) would be the obvious place to look along with the depth of the ocean along the coast and the early removal of sea ice there last year.

I think we'll see similar high temps along all the shelf coasts of the basin as land temps impact the waters beside it. Remember we also saw a dramatic melt of thick ice off the North coast of Greenland through Aug last year (2m over the month if the thickness plots can be trusted) so we do see impacts from a rapidly warming land.

[knocker]

The role of goop: Research shows pollution doesn't change the rate of droplet formation

When it comes to forming the droplets that make up clouds, a little oily and viscous organic material apparently doesn't matter that much. And that's good news for reducing the uncertainty of climate model predictions.

Understanding cloud formation is essential for accurate climate modeling, and understanding cloud formation begins with the droplets that make up clouds. Droplets form when water vapor is attracted to particles floating in the atmosphere. These particles include dust, sea salt from the ocean, microorganisms, soot, sulfur – and organic material that can be both viscous and oily.

For years, scientists had believed that particles coated with this organic "goop" – produced by combusted petroleum and biomass – could form droplets more slowly than other particles. That would have had a significant impact on the formation of clouds.

But a study being reported this week in the journal Proceedings of the National Academy of Science suggests that the long-held belief isn't true. Based on aerial and ground-based measurements of droplet formation from ten different areas of the northern hemisphere, researchers at the Georgia Institute of Technology report that organic coatings on particles don't seem to significantly affect the rate at which droplets form. The researchers studied a wide range of particles, including organic, hydrocarbon-rich particles from the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.

"It turns out that it doesn't matter how much goop you have – or don't have – the droplets take the same time to form," said Athanasios Nenes, a professor in the School of Earth and Atmospheric Sciences and the School of Chemical and Biomolecular Engineering at Georgia Tech. "Even in extreme environments like Deepwater Horizon, the rate of droplet formation on particles found over the spill doesn't differ from that of typical sea salt particles."

http://www.eurekalert.org/pub_releases/2013-02/giot-tro021513.php

[knocker]

Reduced sea ice disturbs balance of greenhouse gases

The widespread reduction in Arctic sea ice is causing significant changes to the balance of greenhouse gases in the atmosphere. This is shown in a new study conducted by researchers from Lund University in Sweden, among others.

According to the study, the melting of sea ice in the Arctic has a tangible impact on the balance of greenhouse gases in this region, both in terms of uptake and release. The researchers have studied the greenhouse gases carbon dioxide and methane both in the tundra and in the Arctic Ocean.

"Changes in the balance of greenhouse gases can have major consequences because, globally, plants and the oceans absorb around half of the carbon dioxide that humans release into the air through the use of fossil fuels. If the Arctic component of this buffer changes, so will the amount of greenhouse gases in the atmosphere", says Dr Frans-Jan Parmentier, a researcher at Lund University, Sweden.

http://www.eurekalert.org/pub_releases/2013-02/lu-rsi021813.php

[knocker]

Jurassic records warn of risk to marine life from global warming

Researchers at Plymouth University, UK, believe that findings from fieldwork along the North Yorkshire coast reveal strong parallels between the Early Jurassic era of 180 million years ago and current climate predictions over the next century.

Through geology and palaeontology, they've shown how higher temperatures and lower oxygen levels caused drastic changes to marine communities, and that while the Jurassic seas eventually recovered from the effects of global warming, the marine ecosystems that returned were noticeably different from before.

The results of the Natural Environment Research Council-funded project are revealed for the first time in this month's PLOS ONE scientific journal.

http://www.eurekalert.org/pub_releases/2013-02/uop-jrw021913.php

[knocker]

Caves point to thawing of Siberia

Evidence from Siberian caves suggests that a global temperature rise of 1.5 degrees Celsius could see permanently frozen ground thaw over a large area of Siberia, threatening release of carbon from soils, and damage to natural and human environments.

A thaw in Siberia's permafrost (ground frozen throughout the year) could release over 1000 giga-tonnes of the greenhouse gases carbon dioxide and methane into the atmosphere, potentially enhancing global warming.

The data comes from an international team led by Oxford University scientists studying stalactites and stalagmites from caves located along the 'permafrost frontier', where ground begins to be permanently frozen in a layer tens to hundreds of metres thick. Because stalactites and stalagmites only grow when liquid rainwater and snow melt drips into the caves, these formations record 500,000 years of changing permafrost conditions, including warmer periods similar to the climate of today.

Records from a particularly warm period (Marine Isotopic Stage 11) that occurred around 400,000 years ago suggest that global warming of 1.5°C compared to the present is enough to cause substantial thawing of permafrost far north from its present-day southern limit.

A report of the research is published in this week's Science Express. The team included scientists from Britain, Russia, Mongolia and Switzerland.

http://www.eurekalert.org/pub_releases/2013-02/uoo-cpt022113.php

[BornFromTheVoid]

Extensive dissolution of live pteropods in the Southern Ocean

This paper reports that marine snails – known as pteropods – living in the seas around Antarctica are being dissolved by ocean acidification. The study used a methodology developed in BAS to classify the damage to pteropod shells and examined this is relation to ocean pH. It discovered severe dissolution of the shells of living pteropods in an area of upwelling. Upwelled water is usually more corrosive to a particular type of calcium carbonate (aragonite) that pteropods use to build their shells, and as a result of the additional influence of ocean acidification, this corrosive water severely dissolved the shells of pteropods.

This first observation of acidification effects on pelagic organisms in polar waters supports predictions that the impact of ocean acidification on marine ecosystems and food webs may be significant. The paper has generated a lot of interest and with the UK ocean acidification cruise currently in the Southern Ocean it will be an influential study that has opened up an important set of research avenues.

BAS page here http://www.antarctic...per.php?id=2078

Paper abstract here http://nora.nerc.ac.uk/20728/

[knocker]

Cambridge, Mass. – February 25, 2013 – “People have often thought there’s no upper bound for wind power—that it’s one of the most scalable power sources,†says Harvard applied physicist David Keith. After all, gusts and breezes don’t seem likely to “run out†on a global scale in the way oil wells might run dry.

Yet the latest research in mesoscale atmospheric modeling, published today in the journal Environmental Research Letters, suggests that the generating capacity of large-scale wind farms has been overestimated.

Each wind turbine creates behind it a "wind shadow" in which the air has been slowed down by drag on the turbine's blades. The ideal wind farm strikes a balance, packing as many turbines onto the land as possible, while also spacing them enough to reduce the impact of these wind shadows. But as wind farms grow larger, they start to interact, and the regional-scale wind patterns matter more.

Keith’s research has shown that the generating capacity of very large wind power installations (larger than 100 square kilometers) may peak at between 0.5 and 1 watts per square meter. Previous estimates, which ignored the turbines' slowing effect on the wind, had put that figure at between 2 and 7 watts per square meter.

In short, we may not have access to as much wind power as scientists thought.

http://www.seas.harvard.edu/news-events/press-releases/rethinking-wind-power

[BornFromTheVoid]

More evidence that its the changes in the Arctic driving much our extreme weather

Weather Extremes Provoked by Trapping of Giant Waves in the Atmosphere

The world has suffered from severe regional weather extremes in recent years, such as the heat wave in the United States in 2011 or the one in Russia 2010 coinciding with the unprecedented Pakistan flood. Behind these devastating individual events there is a common physical cause, propose scientists of the Potsdam Institute for Climate Impact Research (PIK). The study will be published this week in the Proceedings of the National Academy of Sciences and suggests that man-made climate change repeatedly disturbs the patterns of atmospheric flow around the globe's Northern hemisphere through a subtle resonance mechanism...

...Anomalous surface temperatures are disturbing the air flows

Climate change caused by greenhouse-gas emissions from fossil-fuel burning does not mean uniform global warming -- in the Arctic, the relative increase of temperatures, amplified by the loss of snow and ice, is higher than on average. This in turn reduces the temperature difference between the Arctic and, for example, Europe, yet temperature differences are a main driver of air flow. Additionally, continents generally warm and cool more readily than the oceans. "These two factors are crucial for the mechanism we detected," says Petoukhov. "They result in an unnatural pattern of the mid-latitude air flow, so that for extended periods the slow synoptic waves get trapped."

http://www.sciencedaily.com/releases/2013/02/130225153128.htm?utm_source=dlvr.it&utm_medium=twitter

[knocker]

LSU researchers find new information about 'Snowball Earth' period

It is rather difficult to imagine, but approximately 635 million years ago, ice may have covered a vast portion of our planet in an event called "Snowball Earth." According to the Snowball Earth hypothesis, the massive ice age that occurred before animal life appeared, when Earth's landmasses were most likely clustered near the equator, precipitated relatively rapid changes in atmospheric conditions and a subsequent greenhouse heat wave. This particular period of extensive glaciation and subsequent climate changes might have supplied the cataclysmic event that gave rise to modern levels of atmospheric oxygen, paving the way for the rise of animals and the diversification of life during the later Cambrian explosion.

But if ice covered the earth all the way to the tropics during what is known as the Marinoan glaciation, how did the planet spring back from the brink of an ice apocalypse? Huiming Bao, Charles L. Jones Professor in Geology & Geophysics at LSU, might have some of the answers. Bao and LSU graduate students Bryan Killingsworth and Justin Hayles, together with Chuanming Zhou, a colleague at Chinese Academy of Sciences, had an article published on Feb. 5 in the Proceedings of the National Academy of Sciences, or PNAS, that provides new clues on the duration of what was a significant change in atmospheric conditions following the Marinoan glaciation.

http://www.eurekalert.org/pub_releases/2013-02/lsu-lrf022813.php

[knocker]

Now I wonder why temps haven't risen as fast as expected in the last few years?

Volcanic aerosols, not pollutants, tamped down recent Earth warming, says CU-Boulder study

A team led by the University of Colorado Boulder looking for clues about why Earth did not warm as much as scientists expected between 2000 and 2010 now thinks the culprits are hiding in plain sight -- dozens of volcanoes spewing sulfur dioxide.

The study results essentially exonerate Asia, including India and China, two countries that are estimated to have increased their industrial sulfur dioxide emissions by about 60 percent from 2000 to 2010 through coal burning, said lead study author Ryan Neely, who led the research as part of his CU-Boulder doctoral thesis. Small amounts of sulfur dioxide emissions from Earth's surface eventually rise 12 to 20 miles into the stratospheric aerosol layer of the atmosphere, where chemical reactions create sulfuric acid and water particles that reflect sunlight back to space, cooling the planet.

Neely said previous observations suggest that increases in stratospheric aerosols since 2000 have counterbalanced as much as 25 percent of the warming scientists blame on human greenhouse gas emissions. "This new study indicates it is emissions from small to moderate volcanoes that have been slowing the warming of the planet," said Neely, a researcher at the Cooperative Institute for Research in Environmental Sciences, a joint venture of CU-Boulder and the National Oceanic and Atmospheric Administration.

http://www.eurekaler...a-van030113.php

Edited March 1, 2013 by knocker

[knocker]

A new technique to simulate climate change

Statistical physics offers an approach to studying climate change that could dramatically reduce the time and brute-force computing that current simulation techniques require. The new approach focuses on fundamental forces that drive climate rather than on “following every little swirl†of water or air. And yes, there’s an app for that.

http://news.brown.edu/pressreleases/2013/03/climate