Search Results for Tag: Sea level
Arctic sea ice: is the minimum maximum the new normal?
If you blinked, you might have missed it. The confirmation came this week that the Arctic sea ice reached yet another all-time low this past winter. It came and went, without too much ado.
Maybe the excitement was just past. The maximum extent was actually reached on March 7th, but of course you can only be sure it is really not going to spread any further once it has definitely been retreating for some time with the onset of spring.
I was waiting for the NSIDC confirmation, but not with any doubt in my mind that it would tell us officially the maximum for this season would be a minimum.
The danger is a “so what?” kind of reaction, or resignation, with the feeling that nothing short of some kind of unprecedented experimental geo-engineering could save the Arctic summer sea ice in the coming years, as the world continues to warm.
Lowest on record
The National Snow and Ice Data Center (NSIDC), part of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder, and NASA confirmed this week that Arctic sea ice was at a record low maximum extent for the third straight year.
It reached the maximum on March 7, at 14.42 million square kilometers (5.57 milion square miles). Since then, it has started its annual decline with the start of the melt season. Some time in September it will reach its minimum.
This year’s maximum is the lowest in the 38-year satellite record. NSIDC scientists said a very warm autumn and winter had contributed to the record low maximum. Air temperatures were 2.5 degrees Celsius (4.5 degrees Fahrenheit) above average over the Arctic Ocean. Against the background of overall warmth came a series of “extreme winter heat waves over the Arctic Ocean, continuing the pattern also seen in the winter of 2015”, NISDC said in a statement.
The air over the Chukchi Sea northwest of Alaska and the Barents Sea north of Scandinavia was even warmer, averaging around 9 degrees Fahrenheit (five degrees C) above the norm.
NSIDC director Mark Serreze said in his statement: “I have been looking at Arctic weather patterns for 35 years and have never seen anything close to what we’ve experienced these past two winters.”
The winter ice cover was also slightly thinner than that of the past four years, according to data from the European Space Agency’s CryoSat-2 satellite. Data from the University of Washington’s Pan-Arctic Ice Ocean Modeling and Assimiliation System also showed that the ice volume was unusually low for this time of year.
Record summer melt ahead?
“Thin ice and beset by warm weather – not a good way to begin the melt season,”, said NSIDC lead scientist Ted Scambos.
A low maximum does not necessarily mean the minimum to be measured in September will also be a record low, as it depends on summer weather patterns. But Julienne Stroeve from NSIDC and professor of polar observation and modeling at the University College London said “Such thin ice going into the melt season sets us up for the possibility of record low sea ice conditions this September”.
“While the Arctic maximum is not as important as the seasonal minimum, the long-term decline is a clear indicator of climate change”, said Walt Meier, a scientist at the NASA Goddard Space Flight Center Cryospheric Sciences Laboratory and an affiliate scientist at NSIDC. Iceblog readers might wonder if that is stating the obvious, but given the attitudes of the US administration, you can’t take anything for granted.
The September sea ice measurements began to attract attention in 2005, when the ice extent first shrank to a record low over the period of satellite observations. It broke the record again in 2007 and in 2012. There used to be little interest in the maximum extent of the Arctic sea ice at the end of winter. I can remember reading with concern and writing a piece about the maximum extent also reaching a record low in 2015.
“Arctic sea ice extents have followed a steady downward trajectory since the start of the 21st century – at the same time global temperatures have reached new record highs. Betides setting multiple record low summertime minimum extents, Arctic sea ice began to exhibit a pattern of poor winter recovery starting around 2004.”
Living on thin ice
I remember an expedition to Alaska in 2008, when locals at Barrow told me about their personal experiences of the sea ice becoming thinner and less dependable. Some years later I heard similar reports from people in Greenland, who were selling their sled dogs and buying boats in preparation for changing from ice to open water fishing. The data backs them up.
Yereth Rosen, writing for Alaska Dispatch News, draws attention to the problems of continuing to collect that data. She quotes NSIDC’s Serreze:
“Just how well the center will be able to track sea ice in the future remains unclear. No new satellite is expected to be in place until 2020, and there are concerns about potential interruptions in the record that goes back to 1979… We’re at a situation where the remaining passive microwave instruments up there are kind of elderly. If we have satellite failures, we could lose that eye in the sky”.
Now there is a worrying thought.
Against the background of budget cuts proposed by the Trump administration, that – to put it mildly – does not regard tracking climate change as a high priority – scientists are understandably worried about the future of scientific research on climate and environment related issues.
Method in the madness?
Without reliable continuous satellite data, it would be much harder to track how climate change is affecting the polar regions, the ocean and our planet in general. This may well be the intention of climate-change deniers behind the scenes. But climate change itself will not go away – and the impacts will be increasingly evident.
Tim Ellis, writing for Alaska Public media, quotes Serreze as saying the polar ice cap will not last long if the region continues to warm at this rate.
“We are on course sometime in the next few decades, maybe even earlier, to have summers in the Arctic where, you go up there at the end of August, say, and there’s no ice at all.”
“The view from space in the fall of around 2040” , he went on – assuming we still have satellites to take the pictures – “will be of a blue Arctic Ocean, aside from some scattered icebergs and clusters of pack ice”.
I don’t know about you, but I find that a rather depressing thought.
Implications for the rest of the globe
Andrea Thompson, for Climate Central, writes “even in the context of the decades of greenhouse gas-driven warming, and subsequent ice loss in the Arctic, this winter’s weather stood out.”
She also reminds us of the global impacts of a warming Arctic and decline in sea ice:
“The Arctic was one of the clear global hotspots that helped drive global temperatures to the second- hottest February on record and the third-hottest January, despite the demise of a global heat-boosting El Nino last summer.”
This week the UN’s World Meteorological Organisation (WMO) said 2016 had been the hottest year ever recorded, and that the record-breaking heat had continued into 2017, sending the world into “truly uncharted territory”.
“The dramatic melting of Arctic ice is already driving extreme weather that affects hundreds of millions of people across North America, Europe and Asia, according to emerging research”, Damian Carrington writes in the Guardian.
On March 15th, Carrington published an article entitled “Airpocalypse smog events linked to global warming”, referring to extreme smog occurrences in China.
Optimism – the only way to go?
This week I interviewed German oceanologist and climatologist Mojib Latif. I wanted to find out whether the highly unusual extreme rainfall and flooding happening in Peru could be explained by natural cycles or was likely to be a climate change impact which could reoccur. You can read the interview here or listen to it on my Living Planet show this week online or on soundcloud.
The professor stressed that the scientists are baffled, because it is not really the time for an el Nino, although this seems to be a “coastal el Nino”, driven by exceptionally warm water off the coast. Of course he is reluctant to attribute any single event to climate change. He stated unequivocally, though, that the warming of the ocean worldwide was absolutely inexplicable without anthropogenic CO2 emissions, that this is all in line with climate models and that we should all be preparing for an increasing number of increasingly extreme weather events, as the world warms.
He says the governments of the world (apart perhaps from the new US administration) are in no doubt that climate change is happening and they need to halt it. But they have so far failed in their attempts.
When I asked Professor Latif if he still felt optimistic, he told me we really had no other choice. While critical of the lack of government action, he is convinced the world will realize that renewables are ultimately far superior to fossil fuels and will ultimately prevail. The question is whether that will happen in time. As far as the Arctic summer sea ice is concerned, I have to go with a Scots expression: “A hae ma doots”.
DateMarch 24, 2017 | 2:31 pm
TagsAlaska, Arctic, Barrow, China, Climate, el Nino, Emissions, Greenland, ice, IFM-Geomar, Living Planet, polar bears, research, science, sea ice, Sea level, Warming, weather
Greenland ice holds Cold War peril
It sounds like something from a science-fiction novel or a disaster movie. A hidden city under ice, housing 200 people, complete with hospital, cinema, church and research labs – and powered by a mini nuclear reactor. In fact it is reality and lies below the ice of north-west Greenland. The building of Camp Century was started in 1959, by US army engineers.
The camp was abandoned when the glacier above turned out to be shifting much faster than expected in 1967, threatening to crush the tunneled base below. Pollutants including PCBs, tanks of raw sewage and low-level radioactive coolant from the nuclear reactor were left behind.
“When the waste was deposited there, nobody thought it would get out again”, William Colgan, an assistant professor in the Lassonde School of Engineering at York University in Canada, told AFP. Colgan is co-author of a study published in August: Melting Ice could release frozen Cold War-era waste.
Unfortunately, recent research results have told us that the ice island of Greenland is melting even faster than previously thought. A new study published this week in the journal Science Advances using GPS to help estimate how much Greenland ice is melting, comes to the conclusion it is losing around 40 trillion pounds more ice a year than scientists previously thought. That is around 7.6 percent of a difference.
GPS maps past and future ice loss
Most measurements of ice sheet loss use a satellite that measures changes in gravity, and uses computer simulations to calculate the weight loss of ice. But co-author Michael Bevis of Ohio State University told the news agency AP that a portion of the mass calculated by the satellite as ice mass, is actually made up of rocks, which rise up to replace the ice when it goes. This distorts the picture, giving the impression there is more ice than there actually is.
The new study also reconstructs ice loss from Greenland over millennia and comes to the conclusion that it is the same parts of Greenland – the north-west and the south-east – which are losing most ice today as in the distant past. The authors say this means the rapid ice lost we have seen over the last 20 years is part of a long-term trend, being exacerbated by climate change. Damian Carrington in the Guardian, quotes Christopher Harig from the University of Arizona as an independent scientist not involved in the study:
“The new research happening now really speaks to the question: ‘How fast or how much ice can or will melt by the end of the century?’ As we understand more the complexity of the ice sheets, these estimates have tended to go up. In my mind, the time for urgency about climate change really arrived years ago, and it’s past time our policy reflected that urgency.”
Frozen hazards await release
Coming back to Camp Century – here, and elsewhere in the “frozen North”, a lot of the perils once locked safely inside an icy safe are now lurking ready to emerge when the time comes. Colgan led a study published in August in the journal Geophysical Research Letters, which found that higher temperatures could eventually result in toxic waste from the base being released into the environment. By 2090 the amount of ice melting may no longer be offset by snowfall, meaning the toxic chemicals could start leaking into the environment, the study found. Even before that, fissures in the snow could lead to melt water seeping into the crushed tunnels, currently located just 35 metres below the surface.
This is just one spectacular example of a problem that is widespread across the Arctic. Anthrax spores, nuclear waste from subs and reactors … and these are only the human-made dangers. The permafrost is sometimes described as a “time bomb”, with masses of methane and carbon stored as part of natural processes coming to the surface as the world warms.
The news story on AFP centres on who is responsible for cleaning up the pollution from the under-ice camp. The USA and Denmark signed a treaty to permit the construction of Camp Century, code-named “Project iceworm”. Officially, it was to provide a laboratory for Arctic research projects. AFP says it was also home to a “secret US effort to deploy nuclear missiles”. Maybe it was lucky the project had to be abandoned in 1967. But the legacy remains in the form of the nuclear waste left buried under the snow when the reactor was removed.
We have the technology, but…
Study author William Colgan believes the physical logistics of decontaminating the site may not be the biggest challenge involved in all of this. “The environmental hazard is relatively small and far away and there are only a few native towns close by”, AFP quotes.
I was shocked by this statement, which seems to imply that we don’t need to worry about “a few native towns”. I hope I have misunderstood him here. Surely the lives of these small communities should have top priority?
But I can follow his reasoning that establishing which country is responsible for making good the damage is harder than the actual physical clean-up. (He also mentions that the USA and Denmark have experience in similar clean-up operations around the Thule air base, which is around 240 toxic messes or worrying that all our technology cannot prevent destruction of the fragile Arctic environment if we carry out risky operations?)
A worrying precedent
Colgan says the dispute over responsibility “could help set a precedent for other conflicts arising from climate change”. Now that is a very worrying prospect. Unfortunately, it is also a highly realistic one.
When it comes to accepting responsibility for the climate change which is speeding up the melting of Greenland’s huge ice-sheet – and taking action to halt it by abandoning fossil fuels – conflicts are virtually pre-programmed.
When it comes to the costs of dealing with the migration of people forced out of their homes by sea-level rise, flooding, drought, and of ensuring progress for developing countries without climate-harming fossil fuels, states are unlikely to be queuing up to foot the bill.
DateSeptember 26, 2016 | 12:47 pm
TagsArctic, Camp Century, Climate, Cold War, Emissions, Greenland, ice, nuclear, permafrost, research, science, Sea level, toxic waste, USA, Warming
The Rio games have come to an end. Summer is drawing to a close here in Germany. It feels more like autumn today, cool with heavy rainshowers. But there’s a heatwave around the corner after what most people agree has been a very strange summer.
July followed in the record-breaking trend of the earlier months of the year, being the hottest month ever recorded on the planet.
DateAugust 22, 2016 | 1:46 pm
TagsArctic, Climate, CO2, Emissions, glaciers, Greenland, ice, methane, permafrost, sea ice, Sea level, Warming, Zackenberg
Can we halt Arctic melt? Hard question for UN advisor
I had a very interesting high-profile visitor here at Deutsche Welle this week. Bonn, John Le Carré’s “Small Town in Germany” is this country’s UN city nowadays, home to organizations like the climate secretariat UNFCCC and the Convention on Migratory Species, CMS. This year marks 20 years of the former German capital in that new UN role. Fortunately for me and my colleagues, it brings a lot of interesting people to the city.
The University and the City of Bonn have been running a series of lectures by members of the Scientific Advisory Board of the United Nations Secretary-General Ban Ki-Moon this year, under the heading “Global Solutions for Sustainable Development”. This week, it was the turn of Susan Avery, who was President and Director of the Woodshole Oceanographic Institution in the USA until last year. She has been on the advisory board to Ban Ki-Moon for the last three years and she and the other advisors are just finishing their report, so it was great to have the opportunity to talk in length.
Sea and sky as dancing partners
Her lecture was about the importance of the ocean with regard to climate, but she also talked to me about a whole range of ocean-related issues in an interview to be broadcast on our Living Planet programme, starting next week.
Susan Avery is an atmospheric scientist, (the first to head a major oceanographic institution, she told me). She has a very attractive image to describe how the atmosphere and the ocean relate to each other:
“In our planetary system we have two major fluids, the ocean and the atmosphere, and think of them as two dance partners… moving along, but in order to get a choreographic dance, they have to talk to each other. They do that through the ocean-atmosphere interface, which is wave motion, spray, all the things that help them communicate. These two create different dances… an El Nino dance, or a hurricane dance, for example. In reality what they do together is transport heat, carbon and water, which are the major global cycles in our planetary system.”
Since the onset of industrialization, we humans have been introducing some different steps to the dance, it seems:
“When you take it to the climate scale, we talk a lot about the temperature of the atmosphere, increases associated with the infusion of carbon, that is human produced. The thing is that the extra carbon dioxide that gets released into the atmosphere through our fossil fuels and deforestation is associated with extra heat. Of the carbon dioxide we release into the atmosphere, half will stay in the atmosphere, 25% will go into the ocean, 25% will be taken up by the land. But if you look at the heating or warming, 93% of the extra warming is actually in the ocean. There are only very small amounts in the atmosphere.”
Centuries of warming pre-programmed
That means a huge amount of heat is actually being stored in our seas:
“And you can understand why, because the atmosphere is a gas, the ocean is a mass of liquid, which covers two thirds of our planet, and it has a huge heat capacity to store that, but that heat doesn’t just stay at the surface. So (..) when you only talk about heat and temperatures at the surface, you’re ignoring what’s happening below the surface in the ocean, and once the ocean gets heated it’s not going to stay there, because there is this fluid motion. So we’re getting to see greater and greater temperature increases at greater and greater depths. And once that heat gets into the ocean, it can stay there for centuries. Whereas in the upper ocean, it might stay 40 or 50 years, when you get into the deeper parts, because of the density and capacity, it stays there for a long time.”
So, she explained, the carbon dioxide we’ve put into the atmosphere already – and the heating associated with that – means that “we’re already pre-destined for a certain amount of global temperature increase. Many people say we have already pre-destined at least one and a half degree, some will say almost two degrees.”
Now if that is not a sobering thought.
And on top of that comes the acidification of the oceans caused by the extra carbon dioxide, which is playing havoc with coral reef systems and shell-based ocean life forms.
“This is really critical, because it attacks a lot of the base of the food chain for a lot of these eco-systems”.
“What’s in the Arctic is not staying in the Arctic”
Susan Avery’s work has included research on the Arctic and Antarctic, so of course I took the opportunity to ask how she sees all this affecting the polar regions.
She explained how the rapid increase in ice melt in the Arctic – both sea-ice and land ice – caused by atmospheric warming above and warmer ocean waters below, is of great concern for two reasons. The more obvious one is the contribution of land ice melt to sea-level-rise. The other, she explained, is that the melting of the land-based ice results in “a freshening of certain parts of the ocean, so particularly the sub-polar north Atlantic, so you have a potential for interfacing with our normal thermohaline circulation systems which could dramatically change that.” The changes in salinity currently being observed, are a “signal that the water cycle is becoming more vigorous”. This, of course, has major implications for ocean circulation and, in turn, the climate, not just in the region where the ice has been melting:
“What’s in the Arctic is not staying in the Arctic. What’s in the Antarctic is not staying in the Antarctic. I would say the polar regions are regions where we don’t have a lot of time before we see major, massive changes”.
What I find particularly worrying is that Susan Avery confirmed there is still so much we do not know about what is happening in the polar regions and in the ocean in general.
“We really need to get our observations and science and models working together”, she told me. “The new knowledge we have created on processes in the Arctic has to be incorporated into climate system models”.
Paris and the poles
So, given that temperature rise of 1,5 to two degrees Celsius could already be a “given”, and the Arctic is being affected much faster and more strongly than the planet on average, is there any real hope that we can hold up these developments and halt the melting of ice in the Arctic? This was clearly a very difficult question for my guest. She told me she had been very relieved that the Paris Climate Agreement was signed and was sure humankind could still “make things better”. But when I asked whether we will really be able to reverse what is happening in the Arctic or halt climate change in the Antarctic, this was what she replied:
“I don’t have an answer, to be honest. I think we’re still learning a lot about the Arctic and its interface with lower latitudes, how that water basically changes circulation systems, and on what scale. But I think what’s really critically needed right now to get a better sense of the evolution of the Arctic, and of sea level rise, is a real concerted observing network. We know so little, about the Arctic, the life forms underneath the ice. We have the technology. What I really see now is a confluence of new technologies, new analytical approaches, new ways to do ocean science, and all it takes is money to really get those robots there, get the genomic studies that you need, the analysis. We are at the stage where we can do so much, to further our understanding, and I would really put a lot into the Arctic right now, if I had the money to do so.”
Me too, Susan.
Ice: the final frontier?
This brings us back to a key problem I have worried about ever since I started to work on how climate change is affecting the Arctic. That change is speeding up so fast, it is virtually impossible for our research to keep pace. As Susan Avery put it:
“The Arctic will be a major economic zone, we’ve already seen the North-West Passage through the Arctic waters, we’re going to see migration of certain fisheries around the world – and we don’t even know completely what kind of biological life we have below that ice. We have the ability to get underneath the ice now. I call these the frontiers, of the ocean, and that includes looking under ice.”
I am reminded of my trip on board the Helmer Hanssen last year, accompanying a research mission to find out what happens under that ice and down in the deep ocean during the cold, dark season.
(Listen to the audio feature here). There is still so much we do not know about life in the ocean – and it might disappear before we even knew it was there.
DateJuly 8, 2016 | 12:07 pm
TagsArctic, Avery, Ban Ki-Moon, Bonn, Climate, Emissions, ocean, ocean acidification, science, Sea level, UN, Universität Bonn, Warming, Woodshole
Arctic sea ice, Greenland and Europe’s weird weather
As I write this, I am sitting in a short-sleeved shirt with the window open, enjoying an unusually warm start to the month of May. It’s around 27 degrees Celsius in this part of Germany, pleasant, but somewhat unusual at this time. The first four months of this year have been the hottest of any year on record, according to satellite data.
The Arctic is not the first place people tend to think of when it comes to explaining weather that is warmer – as opposed to colder – than usual in other parts of the globe. But several recent studies have increased the evidence that what is happening in the far North is playing a key role in creating unusual weather patterns further south – and that includes heat, at times.
Why sea ice matters
The Arctic has been known for a long time to be warming at least twice as fast as the earth as a whole. As discussed here on the Ice Blog, the past winter was a record one for the Arctic, including its sea ice. The winter sea ice cover reached a record low. Some scientists say the prerequisites are in place for 2016 to see the lowest sea ice extent ever.
Several recent studies have increased the evidence that these variations in the Arctic sea ice cover are strongly linked to the accelerating loss of Greenland’s land ice, and to extreme weather in North America an Europe.
“Has Arctic Sea Ice Loss Contributed to Increased Surface Melting of the Greenland Ice Sheet”, by Liu, Francis et.al, published in the journal of the American Meteorological Society, comes to the conclusion: “Reduced summer sea ice favors stronger and more frequent occurrences of blocking-high pressure events over Greenland.” The thesis is that the lack of summer sea ice (and resulting warming of the ocean, as the white cover which insulates it and reflects heat back into space disappears and is replaced by a darker surface that absorbs more heat) increases occurrences of high pressure systems which get “ stuck and act like a brick wall, “blocking” the weather from changing”, as Joe Romm puts it in an article on “Climate Progress”.
Everything is connected
The study abstract says the researchers found “a positive feedback between the variability in the extent of summer Arctic sea ice and melt area of the summer Greenland ice sheet, which affects the Greenland ice sheet mass balance”. As Romm sums it up:“that’s why we have been seeing both more blocking events over Greenland and faster ice melt.”
He quotes co-author Jennifer Francis of Rutgers University, New Jersey, explaining how these “blocks” can lead to additional surface melt on the Greenland ice sheet, as well as “persistent weather patterns both upstream (North America) and downstream (Europe) of the block.
“Persistent weather can result in extreme events, such as prolonged heat waves, flooding, and droughts, all of which have repeatedly reared their heads more frequently in recent years”, Romm concludes.
“Greenland melt linked to weird weather in Europe and USA” is the headline of an article by Catherine Jex in Science Nordic. People are usually interested in changes in the Greenland ice sheet because of its importance for global sea level, which could rise by around seven metres if it were to melt completely. But Jex also draws attention to the significance of changes to the Greenland ice for the Earth’s climate system as a whole.
The jet stream
“Some scientists think that we are already witnessing the effects of a warmer Arctic by way of changes to the polar jet stream. While an ice-free Arctic Ocean could have big impacts to weather throughout the US and Europe by the end of this century”.
She also notes some scientists warning of “superstorms”, if melt water from Greenland were eventually to shut down ocean circulation in the North Atlantic.
The site contains an interactive map to indicate how changes in Greenland and the Arctic could be driving changes in global climate and environment.
The jet streams drive weather systems in a west-east direction in the northern hemisphere. They are influenced by the difference in temperature between cold Arctic air and warmer mid-latitudes. With the Arctic warming faster than the rest of the planet, this temperature contrast is shrinking, and scientists say the jet streams are weakening.
Jex quotes meteorologist Michael Tjernström, from Stockholm University, Sweden: “Climatology of the last five years shows that the jet has weakened,” says. Its effect on weather around the world is a hot topic.
“We’ve had strange weather for a couple of years. But it’s difficult to say exactly why.”
One explanation, Jex writes, is that a weak jet stream meanders in great loops, which can bring extremes in either cold dry polar air or warmer wetter air from the south, depending on which side of the loop you find yourself. If the jet stream gets “stuck” in this kind of configuration, these extreme conditions can persist for days or even weeks.
Experts have attributed extreme events like the record cold on the east coast of the USA in early 2015, a record warm winter later the same year, and the summer heat waves and mild wet winters with exceptional flooding in the UK to these kind of “kinks” in the jet stream.
Greenland and the ocean
The changes to Greenland’s vast land ice sheet also have consequences for ocean circulation, because they mean an influx of the cold fresh water flowing into the salty sea. And the sea off the east coast of Greenland plays a key role in the movement of water, transporting heat to different parts of the world’s oceans and influencing atmospheric circulation and weather systems.
There have often been “catastrophe scenarios” suggesting the Gulf Steam, which brings warm water and weather from the tropics to the USA and Europe could ultimately be halted, leading to a new ice age. (Remember the “Day after Tomorrow?)
Although this extreme scenario is currently considered unlikely, research does suggest that the major influx of fresh water from melting ice in Greenland and other parts of the Arctic could slow the circulation and result in cooler temperatures in north western Europe.
Jex goes into the theory of a “cold blob” of ocean just south of Greenland, where melt water from the ice sheet accumulates. Some scientists say this indicates that ocean circulation is already slowing down. The “blob” appeared in global temperature maps in 2014. While the rest of the world saw record breaking warm temperatures, this patch of ocean remained unusually cold.
According to a recent study led by James Hansen, from Columbia University, USA, the ‘cold blob’ could become a permanent feature of the North Atlantic by the middle of this century. Hansen and his colleagues claim that a persistent ‘cold blob’ and a full shut down of North Atlantic Ocean circulation could lead to so-called ‘superstorms’ throughout the Atlantic. And there is geological evidence that this has happened before, they say. But the paper was controversial and many climate scientists questioned the strength of the evidence.
However, some scientists already attribute western Europe’s warm and wet winter of 2015 to the “cold blob”, Jex notes, which may have altered the strength and direction of storms via the jet stream.
The good old British weather
The UK’s Independent goes into a new study by researchers at Sheffield University, which indicates soaring temperatures in Greenland are causing storms and floods in Britain. The Independent’s author Ian Johnston says the study “provides further evidence climate change is already happening”.
It never ceases to amaze me that evidence is still being sought for that, but, clearly, there are still those who are yet to be convinced our human behavior is changing the world’s climate. So every bit of scientific evidence helps – especially if it relates to that all-time favourite topic of the weather.
The study also looks at the static areas of high pressure blocking the jet stream. With amazing temperature rises of up to ten degrees Celsius during winter on the west coast of Greenland in just two decades, it is not hard to imagine how this can effect the jet stream, and so our weather in the northern hemisphere.” If forced to go south, the jet stream picks up warm and wet air – and Britain can expect heavy rain and flooding. If forced north, the UK is likely to be hit by cold air from the Arctic”, Johnston writes.
The article quotes Professor Edward Hanna from the University of Sheffield, lead author of a paper about the research published in the International Journal of Climatology, and says seven of the strongest 11 blocking effects in the last 165 years had taken place since 2007, resulting in unusually wet weather in the UK in the summers of 2007 and 2012.
Hanna told the Independent computer models used 10 to 15 years ago to predict the extent of sea ice in the Arctic had significantly underestimated how quickly the region would warm.
“It’s very interesting to look at the observed changes in the Arctic … the actual observations are showing far more dramatic changes than the computer models,” Professor Hanna said.
“You do get sudden starts and jumps. It’s the sudden changes that can take us by surprise and there certainly does seem to have been an increase in extreme weather in certain places.”
Drawing conclusions (or not?)
In the Washington Post, (reprinted on Alaska Dispatch News) Chelsea Harvey sums up the conclusions of the latest research in an article entitled “Dominoes fall: Vanishing Arctic ice shifts jet stream, which melts Greenland glaciers”:
“There are a more complex set of variables affecting the ice sheet than experts had imagined. A recent set of scientific papers have proposed a critical connection between sharp declines in Arctic sea ice and changes in the atmosphere, which they say are not only affecting ice melt in Greenland, but also weather patterns all over the North Atlantic”.
So what do we learn from all of this? Sometimes I ask myself how many times we have to hear a message before we really take it in and decide to do something about it.
Here in Bonn, not far from the office where I am sitting now, the first round of UN climate talks since the Paris Agreement at the end of last year will be kicking off this coming weekend. The aim is to stop the rise in global temperature from going about two, preferably 1.5 degrees C. We have already passed the one degree mark. In an interview with the Guardian this week, the head of the IPCC Hoesung Lee says it is still possible to keep below two degrees, although the costs could be “phenomenal”. But many scientists and other experts are increasingly dubious about whether emissions can really peak in time to achieve the goal. Current commitments by countries to emissions reductions still leave us on the track for three degrees at least.
The concentration of greenhouse gases in the atmosphere is, as the Guardian puts it, “teetering on the brink of no return”, which the landmark 400 ppm measured for the first time at the Australian station at Cape Grim and unlikely to go below the mark again at the Mauna Loa station in Hawaii.
On my desk, I have a book entitled “Arctic Tipping Points”, by Carlos M. Duarte and Paul Wassmann. It was published in 2011. Before that, Professor Duarte had explained the global significance of what is happening in the Arctic to me
at an Arctic Frontiers conference in Tromso, Norway. How much more evidence do we need? Science takes a long time to research, evaluate and publish solid evidence of change and its consequences, with complex review processes. If politicians delay much longer, the pace of climate change will be so fast that action to avert the worst cannot keep up. Meanwhile, that Arctic ice keeps dwindling – and I sense another major storm on the approach.
DateMay 12, 2016 | 11:53 am
TagsADN, AMS, Arctic, Arctic Frontiers, Bonn, Climate, cold blob, Duarte, Emissions, Greenland, Guardian, ice, Independent, International Journal of Climatology, James Hansen, research, Rutgers, science, sea ice, Sea level, Sheffield, tipping point, Tromso, UN talks, UNFCCC, warmest year, Warming