Don Easterbrook, the retired Western Washington University geologist who has made something of a second career out of misunderstanding the Greenland temperature record, appears to be happy to play a very public role in local politics, testifying on climate issues before a Washington State Senate committee last month (video here). His evidence was so far [...]
Posts Tagged Greenland
Don Easterbrook knowingly misleads Washington State Senate Apr 09
Join the conversation at Hot TopicDon Easterbrook is a zombie Mar 18
Join the conversation at Hot Topic
Don Easterbrook is back, and his misunderstanding of Greenland’s climate history rides again in two remarkable posts at µWatts — attempted demolitions of the new paper every denier worth his (or her) salt is frothing at the mouth to claim has been rubbished, the 11,300 year global paleoclimate reconstruction of Marcott et al1. Unfortunately Easterbrook is as far off the mark in his two essays at µWatts (one, two) as he has ever been, which makes not only him look stupid, but everyone who relies on his “work”2.
The easiest thing for me to do to debunk Don would have been to republish this post from January 2011, because all of the points I make there remain true, and are sufficient to discredit Easterbrook’s interpretation of Greenland temperatures and their relevance to Marcott et al, but this time round Don has actually added a couple of extra mistakes — I presume just to keep people like me on their toes. So, for the record, here are Don’s new errors:
- In a graph in his first “paper”, Easterbrook adds 0.7ºC to the last temperature point on the GISP2 Greenland temperature record to represent warming over the last 100 years. As I pointed out two years ago, you can’t use Greenland as a proxy for global temperature changes, because temperatures there are much more variable the global average — approximately twice as variable, as I quantified here. Warming in that part of Greenland has been more like 1.4ºC over the last century.
- In his second “paper”, Easterbrook refers to the “top” of the GISP2 core as being 19503. Unfortunately, he’s wrong (again). The temperature series is dated in years before present (BP), where present is defined as 1950. That makes the last temperature point on the GISP2 reconstruction 95 years before 1950 — in other words, 1855. All the fiddling with local temperature records that he does to try and demonstrate that current Greenland temperatures are not much different to 1950 are not only juvenile4, but wrong headed because he still remains confused about the data he’s fiddling with.
- In one respect he remains entirely consistent: he still can’t spell Kurt Cuffey’s name.
And finally, just to explain why Don and Tony and James and Steve and everyone else have got their knickers in a twist, here’s the big picture: temperatures through the last ice age stitched on to Marcott et al’s Holocene reconstruction, with what we expect to happen over the next century pasted on to the end. If that looks like a brick wall we’re about to run into, then you’re probably right.
[Graph courtesy of Jos Hagelaars and Bart Verheggen]
- A. Marcott, J. D. Shakun, P. U. Clark, A. C. Mix. A Reconstruction of Regional and Global Temperature for the Past 11,300 Years. Science, 2013; 339 (6124): 1198 DOI: 10.1126/science.1228026
- That means the Heartland Institute’s James Taylor, who relies on Easterbrook’s efforts in his latest Forbes article, and looks like a chump because of it. Well, he already looks like a chump in many respects, but this is a doozy, as chump-making status goes.
- “The Medieval Warm Period was 1.1° C warmer than the top of the core (1950)” and “The top of the GISP2 ice core is 1950 AD, so we need to look at more recent temperatures in Greenland in order to get to the ‘present temperature’ ” — a small advance on his earlier belief that the top of the core was 2000AD.
- In one graph he draws a red line between two single years, cherry picking an old reconstruction and single years to get his desired result.
Don Easterbrook is a zombie Mar 18
Join the conversation at Hot TopicDon Easterbrook is back, and his misunderstanding of Greenland’s climate history rides again in two remarkable posts at µWatts — attempted demolitions of the new paper every denier worth his (or her) salt is frothing at the mouth to claim has been rubbished, the 11,300 year global paleoclimate reconstruction of Marcott et al1. Unfortunately Easterbrook is as far off the mark in his two essays at µWatts (one, two) as he has ever been, which makes not only him look stupid, but everyone who relies on his “work”2.
The easiest thing for me to do to debunk Don would have been to republish this post from January 2011, because all of the points I make there remain true, and are sufficient to discredit Easterbrook’s interpretation of Greenland temperatures and their relevance to Marcott et al, but this time round Don has actually added a couple of extra mistakes — I presume just to keep people like me on their toes. So, for the record, here are Don’s new errors:
- In a graph in his first “paper”, Easterbrook adds 0.7ºC to the last temperature point on the GISP2 Greenland temperature record to represent warming over the last 100 years. As I pointed out two years ago, you can’t use Greenland as a proxy for global temperature changes, because temperatures there are much more variable the global average — approximately twice as variable, as I quantified here. Warming in that part of Greenland has been more like 1.4ºC over the last century.
- In his second “paper”, Easterbrook refers to the “top” of the GISP2 core as being 19503. Unfortunately, he’s wrong (again). The temperature series is dated in years before present (BP), where present is defined as 1950. That makes the last temperature point on the GISP2 reconstruction 95 years before 1950 — in other words, 1855. All the fiddling with local temperature records that he does to try and demonstrate that current Greenland temperatures are not much different to 1950 are not only juvenile4, but wrong headed because he still remains confused about the data he’s fiddling with.
- In one respect he remains entirely consistent: he still can’t spell Kurt Cuffey’s name.
And finally, just to explain why Don and Tony and James and Steve and everyone else have got their knickers in a twist, here’s the big picture: temperatures through the last ice age stitched on to Marcott et al’s Holocene reconstruction, with what we expect to happen over the next century pasted on to the end. If that looks like a brick wall we’re about to run into, then you’re probably right.
[Graph courtesy of Jos Hagelaars and Bart Verheggen]
- A. Marcott, J. D. Shakun, P. U. Clark, A. C. Mix. A Reconstruction of Regional and Global Temperature for the Past 11,300 Years. Science, 2013; 339 (6124): 1198 DOI: 10.1126/science.1228026
- That means the Heartland Institute’s James Taylor, who relies on Easterbrook’s efforts in his latest Forbes article, and looks like a chump because of it. Well, he already looks like a chump in many respects, but this is a doozy, as chump-making status goes.
- “The Medieval Warm Period was 1.1° C warmer than the top of the core (1950)” and “The top of the GISP2 ice core is 1950 AD, so we need to look at more recent temperatures in Greenland in order to get to the ‘present temperature’ ” — a small advance on his earlier belief that the top of the core was 2000AD.
- In one graph he draws a red line between two single years, cherry picking an old reconstruction and single years to get his desired result.
Wildfire smoke – bad news for Greenland’s ice: Dark Snow project needs your money Jan 07
Join the conversation at Hot Topic
In this guest post, Professor Jason Box of the Geologic Survey of Denmark and Greenland (yes — he has a new job!) explains the genesis of the Dark Snow Project, a unique crowd-funded scientific expedition to Greenland planned for later this year. If you’ve got a few dollars to spare and want to make a contribution to improving the sum of human knowledge in a place that’s proving crucial to the future of the planet, this is a great way to do it.
Birth of an idea
On my way to my 23rd Greenland expedition, sitting in New York’s LaGuardia airport terminal, completing a 25 June, 2012 blog post about Greenland’s declining reflectivity, I noticed that the crowd in the waiting area were captivated by TV news coverage of the record setting Colorado wildfires. While my recently published work had linked Greenland’s reflectivity (aka albedo, Latin for whiteness) decline with the warming of the previous decade, what remains unresolved is the relative importance wildfire soot that further darkens the ice, acting as a multiplier of the feedback process.
From LaGuardia, I rang fellow Colorado native and NASA JPL snow optics expert Dr. Tom Painter to ask if snow samples plus modern microscopy and chemistry could identify wildfire soot from Colorado?
As we talked, I recalled a 2009 headline: Alaska’s biggest tundra fire sparks climate warning.
“Tom, given samples, is it possible to discriminate wildfire soot with that from industrial sources?”
“Yes,” he said.
Before the flight boarded we had decided it would be a good idea to sample Greenland’s ice and snow for wildfire soot. All we had to do was muster the resources to get to the ice sheet’s highest elevations where the satellite data showed a conspicuous pre-melt reflectivity decline.
7.5% reflectivity decline in July for the upper elevations ice sheet, corresponding with 50 exajoules more solar energy absorption by the ice sheet for this month between 2000 and 2012. For the June-August [summer] period, the ice sheet is now absorbing an additional 1.5 times the total US annual energy consumption. Part of the reflectivity decline is due to the effect of heat, rounding ice crystals, reducing light scattering. Another component is soot. But we don’t know if the effective importance of soot is 1%, 10%, or 50%.
2012, another summer for the record books
By the end of summer 2012, ranking air temperature data from long term weather station records revealed all time records for warmest summer (June-August) at:
- Nuuk in Southwest Greenland in the period of record (PoR) since 1873 [unofficially in the continuous record since 1840]
- Upernavik in Northwest Greenland in the PoR since 1873.
- Summit in central ice sheet Greenland in the PoR since 1988
…and so on for several other stations (Aasiaat, Narsarsuaq) with records beginning in the 1950s and 60s.
As reported by NASA on 24 July, we witnessed the most extensive surface melting over the Greenland ice sheet surface in the continuous satellite passive microwave record that begins in 1978. On 11 July, 98% of the ice sheet surface was melting. This was unprecedented in the satellite observational record and despite claims from the peanut gallery of an event in 1885, there is no evidence of this in the summer air temperature data! See here. Previous maximum melt extents peaked at 65%. Satisfying for me was publishing an accurate prediction of complete surface melting mere weeks before it happened. The prediction was straightforward after finding, in a surface energy budget study, insufficient snowpack ’cold content’ to resist without melting another summer similar to those of the past decade. Melting was right around the corner.
Although I was in Greenland 25 June – 24 July, 2012, because I was overloaded with existing commitments at Store Gletscher, I didn’t realise the goal of sampling high elevation snow for soot.
Another dot, connected
After returning from Greenland, it didn’t take long for me and intern Nathaniel Henry to identify smoke clouds near and over Greenland in NASA satellite-based laser scans of the atmosphere from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) sensor.
The forensics were becoming more compelling. This discovery was reported widely1.
Needed: boots on the ground
The ultimate proof to test our hypothesis that wildfire smoke is contributing in important ways to Greenland’s reflectivity decline depends on the field samples. What we see in satellite imagery are subject to one’s interpretation, hard data speak for themselves.
Please help us make the goal of obtaining the surface samples a reality in our first-of-a-kind crowd-funded Greenland expedition. Make a donation, large or small, in one of the following ways:
- via PayPal at http://darksnowproject.org/ a US tax deductible donation;
- a (US tax deductible) check mailed to Earth Insight Foundation Inc., PO Box 699, San Jose, ca 95106
- mailing a check to Dark Snow attn. Michele Cook, Byrd Polar Research Center, Scott Hall Rm. 108, 1090 Carmack Rd., Columbus, OH, 43210.
- distributing this message in a call for support to those you expect would support Dark Snow Project
- following Dark Snow Project on Facebook and Twitter
[Gareth adds: Peter (Climate Crocks) Sinclair has put together an excellent video overview of the Dark Snow Project:
The year the earth bit back: top climate stories of 2012 Dec 29
Join the conversation at Hot Topic2012Amidst the blizzard of year-end roundups, here’s one you have to read in full — a joint effort put together by a diverse group of bloggers and scientists: Angela Fritz, Eli Rabett, Emilee Pierce, Greg Laden, Joe Romm, John Abraham, Laurence Lewis, Leo Hickman, Michael Mann, Michael Tobis, Paul Douglas, Scott Mandia, Scott Brophy, Stephan Lewandowsky, Tenney Naumer and yours truly. Lead author Greg Laden explains:
A group of us, all interested in climate science, put together a list of the most notable, often, most worrying, climate-related stories of the year, along with a few links that will allow you to explore the stories in more detail. We did not try to make this a “top ten” list, because it is rather silly to fit the news, or the science, or the stuff the Earth does in a given year into an arbitrary number of events. (What if we had 12 fingers, and “10” was equal to 6+6? Then there would always be 12 things, not 10, on everyone’s list. Makes no sense.) We ended up with 18 items, but note that some of these things are related to each other in a way that would allow us to lump them or split them in different ways. See this post by Joe Romm for a more integrated approach to the year’s events. Also, see what Jeff Masters did here. We only included one non-climate (but related) item to illustrate the larger number of social, cultural, and political things that happened this year. For instance, because of some of the things on this list, Americans are more likely than they were in previous years to accept the possibility that science has something to say about the Earth’s climate and the changes we have experienced or that may be in the future; journalists are starting to take a new look at their own misplaced “objective” stance as well. Also, more politicians are starting to run for office on a pro-science pro-environment platform than has been the case for quite some time.
A failing of this list is that although non-US based people contributed, and it is somewhat global in its scope, it is a bit American based. This is partly because a few of the big stories happened here this year, but also, because the underlying theme really is the realisation that climate change is not something of the future, but rather, something of the present, and key lessons learned in that important area of study happened in the American West (fires) the South and Midwest (droughts, crop failures, closing of river ways) and Northeast (Sandy). But many of the items listed here were indeed global, such as extreme heat and extreme cold caused by meteorological changes linked to warming, and of course, drought is widespread.
1: Super Storm Sandy
Super Storm Sandy, a hybrid of Hurricane Sandy (and very much a true hurricane up to and beyond its landfall in the Greater New York/New Jersey area) was an important event for several reasons. First, the size and strength of the storm bore the hallmarks of global warming enhancement. Second, its very unusual trajectory was caused by a climatic configuration that was almost certainly the result of global warming. The storm would likely not have been as big and powerful as it was, nor would it have likely struck land where it did were it not for the extra greenhouse gasses released by humans over the last century and a half or so.
A third reason Sandy was important is the high storm surge that caused unprecedented and deadly flooding in New York and New Jersey. This surge was made worse by significant global warming caused sea level rise. Sea level rise has been eating away at the coasts for years and has probably caused a lot of flooding that otherwise would not have happened, but this is the first time a major event widely noticed by the mainstream media (even FOX news) involving sea level rise killed a lot of people and did a lot of damage. Fourth, Sandy was an event, but Sandy might also be the “type specimen” for a new kind of storm. It is almost certainly true that global warming Enhanced storms like Sandy will occur more frequently in the future than in the past, but how much more often is not yet known. We will probably have to find out the hard way.
Note that the first few of the links below are to blog posts written by concerned climate scientists, whom the climate change denialists call “alarmists.” You will note that these scientists and writers were saying alarming things as the storm approached. You will also note that what actually happened when Sandy struck was much worse than any of these “alarmists” predicted in one way or another, in some cases, in several ways. This then, is the fifth reason that Sandy is important: The Earth’s weather system (quite unconsciously of course) opened a big huge can of “I told you so” on the climate science denialist world. Sandy washed away many lives, a great deal of property and quite a bit of shoreline. Sandy also washed away a huge portion of what remained of the credibility of the climate science denialist lobby.
Is Mother Nature revving up an October Surprise (w/ human thumbs on the scale)?
Has climate change created a monster?
Ostrich Heads in the Sand(y)? Does your meteorologist break the climate silence?
Climate of Doubt As Superstorm Sandy Crosses US Coast
Are Tropical Storms Getting Larger in Area?
What you need to know about Frankenstorm Sandy
[Fox: Hurricane Sandy Has “Nothing To Do With Global Warming” ]
2: Related to Sandy, the direct effects of sea level rise…
… were blatantly observed and widely acknowledged by the press and the public for the first time
Sea Level Rise … Extreme History, Uncertain Future
Peer Reviewed Research Predicted NYC Subway Flooding by #Sandy
3: The Polar Ice Caps and other ice features experienced extreme melting this year.
This year, Arctic sea ice reached a minimum in both extent (how much of the sea is covered during the Arctic summer) and more importantly, total ice volume, reaching the lowest levels in recorded history.
Arctic sea ice extent settles at record seasonal minimum
Ice Loss at Poles Is Increasing, Mainly in Greenland
[TV Media Cover Paul Ryan’s Workout 3x More Than Record Sea Ice Loss]
4: Sea Ice Loss Changes Weather …
We also increasingly recognised that loss of Arctic sea ice affects Northern Hemisphere weather patterns, including severe cold outbreaks and storm tracks. This sea ice loss is what set up the weather pattern mentioned above that steered Sandy into the US Northeast, as well as extreme cold last winter in other areas.
Arctic Warming is Altering Weather Patterns, Study Shows
5 and 6: Two major melting events happened in Greenland this summer.
First, the total amount of ice that has melted off this huge continental glacier reached a record high, with evidence that the rate of melting is not only high, but much higher than predicted or expected. This is especially worrying because the models climatologists use to predict ice melting are being proven too optimistic. Second, and less important but still rather spectacular, was the melting of virtually every square inch of the surface of this ice sheet over a short period of a few days during the hottest part of the summer, a phenomenon observed every few hundred years but nevertheless an ominous event considering that it happened just as the aforementioned record ice mass loss was being observed and measured.
[Media Turn A Blind Eye To Record Greenland Ice Melt]
7: Massive Ice islands…
…were formed when the Petermann Glacier of northern Greenland calved a massive piece of its floating tongue, and it is likely that the Pine Island Glacier (West Antarctica) will follow suit this Southern Hemisphere summer. Also, this information is just being reported and we await further evaluation. As summer begins to develop in the Southern Hemisphere, there may be record warmth there in Antarctica. That story will likely be part of next year’s roundup of climate-related woes.
8: More Greenhouse Gasses than Ever
Even though the rate of emissions of greenhouse gasses slowed down temporarily for some regions of the world, those gasses stay in the air after they are released, so this year greenhouse gas levels reached new record high levels
United StatesGreenhouse Gas Levels Reach New Record High
World Meteorological Organization: Greenhouse Gas Concentrations Reach New Record
9: It Got Hot
As expected, given the greenhouse gases just mentioned, Record Breaking High Temperatures Continue, 2012 is one of the warmest years since the Age of the Dinosaurs. We’ll wait until the year is totally over to give you a rank, but it is very, very high.
UK Met Office forecasts next year to set new record
Global Warming’s Terrifying New Math
10: …and that heat brought extreme, killer heat waves
Hot, Very Hot, Extremely Hot Summers
[STUDY: TV Media Ignore Coverage of Climate Change In Coverage Of Record July Heat]
11: For many areas, this was the year without a Spring.
The growing season in temperate zones is longer, causing the USDA in the US to change its planting recommendations.
12: There were widespread, unprecedented and deadly wildfires…
…around the world and in the American West.
[STUDY: Media Avoid Climate Context In Wildfire Coverage]
[STUDY: Media Begin To Connect The Dots Between Climate Change And Wildfires]
13: There was a major drought…
…in the US with numerous negative effects including threats to the food supply
What is the link between Global Warming and Drought?
Brutal Droughts, Worsened by Global Warming, Threaten Food Production Around The World
Alarm bells on climate change as extreme weather events sweep the world: CCSOS
14: River Traffic Stops
A very rare event caused by drought conditions was the closing of the Mississippi River to traffic in mid-summer at two locations. This is part of a larger and growing problem involving drought, increased demands for water, and the importance of river traffic. Expect to hear more about this over the next couple of years.
Drought Closes Mississippi River Traffic in Two Locations
15: Very, very bad storms.
In June, a major and very scary derecho event – a thunderstorm and tornado complex large enough to get its own Wikipedia entry – swept across the country. This was one of several large storm systems that caused damage and death in the US this year. There were also large and unprecedented sandstorms in Asia and the US.
June 2012 North American derecho
16: Widespread Tree Mortality is underway and is expected to worsen.
Dire Drought Ahead, May Lead to Massive Tree Death
17: Biodiversity is mostly down…
We continue to experience, and this will get worse, great Losses in Biodiversity especially in Oceans, much of that due to increased acidification because of the absorption of CO2 in seawater, and overfishing.
Big loss of biodiversity with global warming
18: Unusual Jet Stream Configuration and related changes to general climate patterns…
Many of us who contributed to this list feel that this is potentially the most important of all of the stories, partly because it ties together several other events. Also, it may be that a change in the air currents caused by global warming represents a fundamental yet poorly understood shift in climate patterns. The steering of Hurricane Sandy into the New York and New Jersey metro areas, the extreme killer cold in Eastern Europe and Russia, the “year without a Spring” and the very mild winters, some of the features of drought, and other effects may be “the new normal” owing to a basic shift in how air currents are set up in a high-CO2 world. This December, as we compile this list, this effect has caused extreme cold in Eastern Europe and Russia as well as floods in the UK and unusually warm conditions in France. As of this writing well over 200 people have died in the Ukraine, Poland and Russia from cold conditions. As an ongoing and developing story we are including it provisionally on this list. Two blog posts from midyear of 2011 and 2012 (this one and this one) cover some of this.
The following video provides an excellent overview of this problem:
19: The first climate denial “think” tank to implode as a result of global warming…
… suffered major damage this year. The Heartland Institute, which worked for many years to prove that cigarette smoking was not bad for you, got caught red handed trying to fund an effort explicitly (but secretly) designed to damage science education in public schools. Once caught, they tried to distract attention by equating people who thought the climate science on global warming is based on facts and is not a fraud with well-known serial killers, using large ugly billboards. A large number of Heartland Institute donors backed off after this fiasco and their credibility tanked in the basement. As a result, the Heartland Institute, which never was really that big, is now no longer a factor in the climate change discussion.
Arctic records tumble as ice melts: 2012 Arctic report card released at AGU Dec 06
Join the conversation at Hot TopicThe latest Arctic Report Card was published yesterday at the American Geophysical Union’s Fall Meeting in San Francisco, and it makes grim reading. Apart from last summer’s new record low sea ice minimum, all the indicators of warming are pointing in the wrong direction. The Arctic is making a rapid transition to a new climate state. Highlights of the report (from the press release):
- Snow cover: A new record low snow extent for the Northern Hemisphere was set in June 2012, and a new record low was reached in May over Eurasia.
- Sea ice: Minimum Arctic sea ice extent in September 2012 set a new all-time record low.
- Greenland ice sheet: There was a rare, nearly ice sheet-wide melt event on the Greenland ice sheet in July, covering about 97 percent of the ice sheet on a single day.
- Vegetation: The tundra is getting greener and there’s more above-ground growth. During the period of 2003-2010, the length of the growing season increased through much of the Arctic.
- Wildlife & food chain: In northernmost Europe, the Arctic fox is close to extinction and vulnerable to the encroaching Red fox. Massive phytoplankton blooms below the summer sea ice suggest that earlier estimates of biological production at the bottom of the marine food chain may have been ten times lower than was occurring.
- Ocean: Sea surface temperatures in summer continue to be warmer than the long-term average at the growing ice-free margins, while upper ocean temperature and salinity show significant interannual variability with no clear trends.
- Weather: Most of the notable weather activity in fall and winter occurred in the sub-Arctic due to a strong positive North Atlantic Oscillation, expressed as the atmospheric pressure difference between weather stations in the Azores and Iceland. There were three extreme weather events including an unusual cold spell in late January to early February 2012 across Eurasia, and two record storms characterized by very low central pressures and strong winds near western Alaska in November 2011 and north of Alaska in August 2012.
It’s well worth digging down beyond the executive summary to look at the individual reports for key elements in the Arctic — there’s a lot of detail to digest, all of it fascinating, much of it sobering, if not downright scary. This is rapid climate change, happening now. I wonder if anyone in Doha will notice?
Ice bottom blues Sep 19
Join the conversation at Hot TopicAccording to the latest bulletin from the National Snow and Ice Data Center in the US, Arctic sea ice is likely to be at or about its minimum extent for the summer (as of Sept 17th). The animation above shows how the ice melt proceeded through the summer (up to Sept 14th), and the graph below shows the extent as of Sept 17th — 3.41 million square kilometres (1.32 million square miles).
The NSIDC notes:
The current extent is 760,000 square kilometres (293,000 square miles) below the previous record minimum extent in the satellite record (4.17 million square kilometres or 1.61 million square miles) which occurred on September 18, 2007. This difference is larger than the size of the state of Texas. The ice extent currently tracks nearly 50% below the 1979 to 2000 average minimum extent.
For an insight into what the ice is really like, I recommend Julienne Stroeve’s blog of her trip on the Greenpeace vessel Arctic Sunrise. This is from her most recent entry (Sept 17th):
I have been surprised by the vast expanses of open water that we came upon after entering the ice. The average ice concentration of the last five days has been about 65 percent, with about 36 percent of that ice being first-year ice, 14 percent being multiyear ice and 10 percent being brash ice (small broken ice floes). Air temperatures have been above freezing, even at 82.82N, 15.16E, so that there have been no new ice formation observed the last five days.
Viewers and listeners to the last Climate Show (and my Radio Ecoshock interview before it) will know something of my thinking on what all this portends, but I’ll have a post pulling it all together once the minimum is finally called.
Elsewhere in the Arctic, this year’s Petermann ice island is motoring south down Nares Strait, as this NASA Earth Observatory image shows.
To get an idea just how big this lump of ice is, note that the scale bar in the bottom right of the image is 100 kilometres. It’s big.
Meanwhile, professor Peter Wadhams, head of the Polar Ocean Physics Group at Cambridge, has told the Guardian that he expects the Arctic to be ice-free1 means in summer (Aug/Sept) within four years. Given this summer, I can’t say that I find much to disagree with in his prognosis.
This is not good news.
[Update Sept 20th: NSIDC calls minimum at 3.41 m km2. Good NASA article with excellent graphics here.]
- Most people define “ice-free” to be 1 million km2 remaining — the thick ice close to the Canadian archipelago — but it’s not clear from the Guardian if this is how Wadhams defines it.
Why Arctic sea ice shouldn’t leave anyone cold Aug 26
Join the conversation at Hot TopicIn this guest post Neven Acropolis, the man behind the excellent Arctic Sea Ice blog, looks at the reasons why we need to pay attention to the rapid loss of sea ice in the Arctic Ocean.
Arctic sea ice became a recurrent feature on planet Earth around 47 million years ago. Since the start of the current ice age, about 2.5 million years ago, the Arctic Ocean has been completely covered with sea ice. Only during interglacials, like the one we are in now, does some of the sea ice melt during summer, when the top of the planet is oriented a bit more towards the Sun and receives large amounts of sunlight for several summer months. Even then, when winter starts, the ice-free portion of the Arctic Ocean freezes over again with a new layer of sea ice.
Since the dawn of human civilisation, 5000 to 8000 years ago, this annual ebb and flow of melting and freezing Arctic sea ice has been more or less consistent. There were periods when more ice melted during summer, and periods when less melted. However, a radical shift has occurred in recent times.
Ever since satellites allowed a detailed view of the Arctic and its ice, a pronounced decrease in summer sea ice cover has been observed (with this year setting a new record low). When the IPCC released its Fourth Assessment Report in 2007, it was generally thought that the Arctic could become ice-free somewhere near the end of this century. But changes in the Arctic have progressed at such speed that most experts now think 2030 might see an ice-free Arctic for the first time. Some say it could even happen this decade.
What makes this event significant, is the role Arctic sea ice plays as a reflector of solar energy. Ice is white and therefore reflects a large part of incoming sunlight back out to space. But where there is no ice, dark ocean water absorbs most of the sunlight and thus heats up. The less ice there is, the more the water heats up, melting more ice. This feedback has all kinds of consequences for the Arctic region.
Disappearing ice can be good for species such as tiny algae that profit from the warmer waters and extended growing season, but no sea ice could spell catastrophe for larger animals that hunt or give birth to offspring on the ice. Rapidly changing conditions also have repercussions for human populations whose income and culture depend on sea ice. Their communities literally melt and wash away as the sea ice no longer acts as a buffer to weaken wave action.
But what happens in the Arctic, doesn’t stay in the Arctic. The rapid disappearance of sea ice cover can have consequences that are felt all over the Northern Hemisphere, due to the effects it has on atmospheric patterns. As the ice pack becomes smaller ever earlier into the melting season, more and more sunlight gets soaked up by dark ocean waters, effectively warming up the ocean. The heat and moisture that are then released to the atmosphere in fall and winter could be leading to disturbances of the jet stream, the high-altitude wind that separates warm air to its south from cold air to the north. A destabilised jet stream becomes more ‘wavy’, allowing frigid air to plunge farther south, a possible factor in the extreme winters that were experienced all around the Northern Hemisphere in recent years.
Another side-effect is that as the jet stream waves become larger, they slow down or even stall at times, leading to a significant increase in so-called blocking events. These cause extreme weather simply because they lead to unusually prolonged conditions of one type or another. The recent prolonged heatwave, drought and wildfires in the USA are one example of what can happen; another is the cool, dull and extremely wet first half of summer 2012 in the UK and other parts of Eurasia.
The accumulation of heat in Arctic waters also influences other frozen parts of the Arctic, such as glaciers and ice caps on Greenland and in the Canadian archipelago. As there is less and less sea ice to act as a buffer, more energy can go into melting glaciers from below and warming the air above them. This has a marked effect on Greenland’s marine-terminating glaciers and the Greenland ice sheet.
Not only are glaciers flowing faster towards sea, but there is also a rapid increase in the summer surface melt Greenland experiences, leading to accelerating mass loss from the Greenland Ice Sheet. As the Arctic warms, an increased contribution to sea level rise is inevitable.
Another way Arctic warming could have worldwide consequences is through its influence on permafrost. Permanently frozen soils worldwide contain 1400-1700 Gigatons of carbon, about four times more than all the carbon emitted by human activity in modern times. A 2008 study found that a period of abrupt sea-ice loss could lead to rapid soil thaw, as far as 900 miles inland.
Apart from widespread damage to infrastructure (roads, houses) in northern territories, resulting annual carbon emissions could eventually amount to 15-35 percent of today’s yearly emissions from human activities, making the reduction of greenhouse gases in the atmosphere a much more difficult task.
An even more worrying potential source of greenhouse gases is the methane in the seabed of the Arctic Ocean, notably off the coast of Siberia. These so-called clathrates contain an estimated 1400 Gigatons of methane, a more potent though shorter-lived greenhouse gas than carbon dioxide. Methane clathrate, a form of water ice that contains a large amount of methane within its crystal structure, remains stable under a combination of high pressure and low temperature. At a depth of 50 meters or less the East Siberian Arctic Shelf contains the shallowest methane clathrate deposits, and is thus most vulnerable to rising water temperatures. Current average methane concentrations in the Arctic already average about 1.90 parts per million, the highest in 400,000 years.
Apart from these unrecoverable sources of fossil fuel the Arctic is also endowed with large amounts of recoverable oil and natural gas. As the sea ice retreats, the Arctic’s fossil treasures are eyed greedily by large corporations and nations bordering the Arctic Ocean. Not only might this lead to geopolitical tensions in a world where energy is rapidly becoming more expensive, it is also highly ironic that the most likely cause of the disappearance of Arctic sea ice – the extraction and burning of fossil fuels – could lead to more extraction of said fuels. Another feedback loop.
News articles referring to the Arctic and its sea ice usually have pictures of polar bears accompanying the text. But although many animals in the Arctic will be impacted negatively by the vanishing of Arctic sea ice, much more is at stake. After thousands of years in which the sea ice played a vital role in the relatively stable conditions under which modern civilisation, agriculture and a 7 billion strong world population could develop, it increasingly looks as if warming caused by the emission of greenhouse gases is bringing an end to these stable conditions. Whether there still is time to save the Arctic sea ice, is difficult to tell, but consequences will not disappear when the ice is gone. It seems these can only be mitigated by keeping fossil fuels in the ground and out of the air. Whichever way you look at it, business-as-usual is not an option.
For more information on Arctic sea ice, check out Neven’s Arctic Sea Ice blog.
Image credits:
Arctic sea ice extent reconstruction – Kinnard et al. 2011
Sea ice albedo feedback – NASA
Polar jet stream – NC State University
Greenland ice sheet surface melt – NASA
Permafrost distribution in the Arctic – GRID-Arendal
Atmospheric methane concentration – NOAA ESRL
Russia plants flag at North Pole – Reuters
Deep Water Aug 18
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We know that sea level rise is an inevitable consequence of the global warming that our continued burning of fossil fuels is causing. What we don’t know is how much to expect and how soon to expect it. Journalist Daniel Grossman in his Kindle Single Deep Water: As Polar Ice Melts, Scientists Debate How High Our Oceans Will Rise explores the momentous issue by looking at the work of three scientists who study the past history of elevated sea levels to get a better understanding of what is likely ahead for humanity. Grossman writes from a close acquaintance with climate science and his ability to distil the science in readily understandable form for the general reader is outstanding.
Paul Hearty, “talented and cantankerous”, is a geologist who has argued from his studies of inter-glacial periods that if the Earth warms by two degrees the huge glaciers in Greenland and Antarctica could substantially melt in a short space of time. His field work in the Bahamas and Bermuda, which he regards as a relatively stable region geologically, has led him to the conclusion that in the warm interglacial 400,000 years ago (Stage 11) sea level rose by as much as around 19 metres. Paleoclimatologist Maureen Raymo doesn’t share that view but it was Hearty she invited in 2009 to collaborate in field work with her in Western Australia seeking evidence of sea level rise in the Pliocene. Grossman travelled with them as journalist and gives a lively account of the expedition.
Raymo’s respect for Hearty’s field work is considerable, and for some time she felt he had established the case for a higher sea level rise in the Stage 11 interglacial than most credited. Then it occurred to her that the Bahamas and Bermuda may have been involved in vertical lift as the great weight of the Laurentide ice sheet depressed the land on which it sat, causing a bulge in surrounding crust. Grossman uses the analogy of a waterbed to illustrate the effect. When the ice sheet subsequently melts the depressed land rises and the surrounding bulges sink. The Stage 11 interglacial on which Hearty’s work was focused was a long one, allowing, she surmised, more time for the subsidence of Bermuda and the Bahamas than has yet occurred in our own period. Raymo took her theory to geophysicist Jerry Mitrovica who applied the adjustment factors that he had worked out over the years as he studied unique local circumstances which affect local sea level change relative to global average change. By his calculations the Bahamas and Bermuda had indeed subsided much more during the Stage 11 interglacial than they have today. Some 8.5 metres more in fact, meaning that the sea level rise recorded in Hearty’s findings was close to the 9.4 metres proposed by most other researchers.
The matter is not settled, of course, and Hearty is not persuaded. But it’s a fascinating picture Grossman presents of scientific argument and counter-argument. And if Hearty’s conclusions prove mistaken, he is not mistaken in finding that the features he locates in the field are in fact evidence of a shore line, not the result of storm winds or tsunamis as some have suggested.
Grossman has chronicled a scientific debate which may mean that the sea level rise we can eventually expect, as the global temperature continues to rise, will be more like 9 metres than 19. There’s no comfort for humanity there. Denialists inclined to make something out of the difference of opinion would be well astray. As Mitrovica comments, 9 metres is still plenty of water. And he is troubled by work he has shared on the most recent interglacial, which also reached a temperature only a little warmer than today’s. Yet that appears to have been enough to cause the Greenland and West Antarctic ice sheets to lose most of their ice and sea level to rise by around 7 metres over time, which points to the possibility of a higher sea level rise this century than previous estimates.
Grossman reports that most scientists with whom he has spoken expect a sea level rise of around a metre this century. But there is profound uncertainty about the behaviour of the ice sheets of Greenland and Antarctica. Will these continent-scale glaciers remain languid in their transport of ice to the sea or under the influence of warming will they become more akin to bounding torrents? He explains very clearly for the lay reader the difference between the gradual surface melting of an ice-cube and the dynamics of glacier movement that can cast into the sea quantities of ice which dwarf the amounts that dribble off from surface melting.
Grossman’s short book is science journalism at its best, informative, accessible, and yes, entertaining. It’s an intriguing first hand glimpse into paleoclimatologists at work, piecing together the results of their research, sometimes conflicting in their conclusions but pointing undeniably towards grave consequences for humanity if we set in train the disintegration of the world’s major ice sheets. There is clearly warning enough, in spite of the uncertainties, that the danger is real and may already be in process. That’s the seriousness underlying the highly readable narrative in which the book is cast.
Note: There’s a useful article in The Yale Forum on Climate Change and the Media discussing TED Books, the digital books publisher of Deep Water, and referring to Grossman’s book in that context.
Greenland’s extraordinary summer #3: new record melt year, and summer’s not over yet Aug 16
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Greenland’s amazing summer continues, with news today that the ice sheet has already set a new record for surface melting — with four weeks of the melt season still to run. The ice sheet surpassed the previous record year, 2010, on August 8th. Marco Tedesco of the City College of New York said:
“With more yet to come in August, this year’s overall melting will fall way above the old records. That’s a goliath year – the greatest melt since satellite recording began in 1979.”
Tedesco and his team calculate the duration and extent of melt over the ice sheet, using satellite data to develop a ‘cumulative melting index’. The index is defined as the number of days when melting occurs multiplied by the total area subject to melting, and is a measure of how much melting has occurred in a season that normally runs from June to September. As the chart below demonstrates, by August 8th the melt was already well ahead of 2010.
So far this year Greenland has experienced extreme melt in virtually every corner of the ice sheet, and especially at high altitudes. When summer’s over, and the research teams ponder the data they’ve gathered on the ice, it seems pretty clear that there are going to be some interesting figures to consider, with consequences for everyone with beachfront property… Follow Tedesco’s work, and that of other teams working on Greenland on his Greenland Melting site.