Search Results for Tag: NOAA
Arctic thaw – carry on regardless?
When a colleague who has a lot of sympathy for those who do NOT accept that humans are responsible for global warming drew attention to the fact that this had been the hottest June on record, following hard on the hottest May, I must admit I was temporarily put of my guard. Aha, I thought. Is he finally getting the message? Alas, the answer is no. There is a small minority of people that still argues – for whatever reason – that natural variation could be responsible for all this, while acknowledging the record concentration of CO2 in the atmosphere. “And all that stuff”. Hm.
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Arctic summers to be ice-free earlier?
Scientists studying Arctic sea ice say ice-free summers could be on the horizon sooner than many expected. A new analysis by NOAA scientists James Overland (NOAA Pacific marine Environmental Laboratory) and Muyin Wang (NOAA Joint Institute for the Study of Atmosphere and Ocean at the University of Washington) considered three methods of predicting when the Arctic will be nearly ice free in the summer. All three suggest nearly ice-free summers in the Arctic before the middle of this century, says Wang, although the actual dates differ widely. One method suggests the Arctic could be nearly sea ice free in summer as early as 2020.
“Rapid Arctic sea ice loss is probably the most visible indicator of global climate change; it leads to shifts in ecosystems and economic access, and potentially impacts weather throughout the northern hemisphere,” said Overland. “Increased physical understanding of rapid Arctic climate shifts and improved models are needed that give a more detailed picture and timing of what to expect so we can better prepare and adapt to such changes. Early loss of Arctic sea ice gives immediacy to the issue of climate change.”
The paper was published recently online in Geophysical Research Letters.
Overland said the differences between the models could lead some people to conclude that models are not useful. In fact the opposite is the case, he said. “Models are based on chemical and physical climate processes and we need better models for the Arctic as the importance of that region continues to grow.”
Taken together, the range among the multiple approaches still suggests that it is very likely that the timing for future sea ice loss will be within the first half of the 21st century, with a possibility of major loss within a decade or two, the authors say.
Other recent studies have indicated the key role of shrinking Arctic sea ice in influencing our weather. The shrinking sea ice is shifting polar weather patterns, especially in autumn and winter, according to one new climate modeling study.
Researchers looked at weather patterns in 2007, when sea ice covering the Arctic Ocean hit one of its lowest summer extents since satellite tracking began in the late 1970s.
In autumn and winter, when sea ice would normally insulate the ocean from frigid Arctic air temperatures, the small ice pack meant lots of heat could escape from the ocean into the atmosphere, the study found. The heating changed atmospheric circulation patterns in the Arctic, said study leader Elizabeth Cassano, a climate scientist at the Cooperative Institute for Research in Environmental Sciences (CIRES) in Boulder, Colorado. The results were published May 21 in the International Journal of Climatology.
Becky Oskin from LiveScience talked to Cassano about the study and quotes: “What we saw, particularly in the fall and winter, was a decrease in [atmospheric] pressure over the areas of open water.” Areas of high and low pressure drive weather, with low pressure producing stormier weather and high pressure leading to clear, calm days, Cassano said. The group’s computer model generally agreed with weather records from the latter half of 2007, according to the study.
While the summer ice melt had a significant effect into the winter, there was little change in weather patterns in early 2007, before the ice pack shrank, the study found. However, Cassano points out that the climate model doesn’t include a major high-pressure system that was in the Beaufort Sea north of Alaska and played a role in the big ice melt. Its absence could affect the modeling results.
The researchers now plan to examine how the feedback between sea ice and the atmosphere alters weather in the United Statse and other regions, Cassano said. “There’s an open question of how these changes that we see in the Arctic influence the weather that we see here in the mid-latitudes,” she said.
Given the weird weather we are experiencing in different parts of Europe at the moment, interest in whether climate change could be directly or indirectly responsible is high. Finnish Lapland has been experiencing a heatwave. Colleagues of mine have returned from the south of France complaining it was unexpectedly cold. Here in the normally mild Rhineland, we have also had very low temperatures and heavy rain. Meanwhile southern and eastern parts of Germany are being hit by severe flooding.
Renowned German scientist Stefan Rahmstorf and his colleagues at the Potsdam Institute for Climate Impact Research have apparently been contacted by various media, asking them if the rain and flooding are connected to climate change. He refers readers to a study on extreme weather they published in Nature Climate Change a year ago. Let me close by sharing his quote from that study, which he shares again in the climate blog SciLogs:
“Many climate scientists (including ourselves) routinely answer media calls after extreme events with the phrase that a particular event cannot be directly attributed to global warming. This is often misunderstood by the public to mean that the event is not linked to global warming, even though that may be the case — we just can’t be certain. If a loaded dice rolls a six, we cannot say that this particular outcome was due to the manipulation — the question is ill-posed. What we can say is that the number of sixes rolled is greater with the loaded dice (perhaps even much greater). Likewise, the odds for certain types of weather extremes increase in a warming climate (perhaps very much so). Attribution is not a ‘yes or no’ issue as the media might prefer, it is an issue of probability. It is very likely that several of the unprecedented extremes of the past decade would not have occurred without anthropogenic global warming. Detailed analysis can provide specific numbers for certain types of extreme, as in the examples discussed above.
In 1988, Jim Hansen famously stated in a congressional hearing that “it is time to stop waffling so much and say that the evidence is pretty strong that the greenhouse effect is here”. We conclude that now, more than 20 years later, the evidence is strong that anthropogenic, unprecedented heat and rainfall extremes are here — and are causing intense human suffering.”
Arctic Alarm
This week’s Arctic news has been pretty drastic. The current autumn temperature is five degrees higher than the average. 2007 was the warmest year ever in the Arctic, since people started to record the temperature. The sea ice, as we know, has decreased dramatically.
This is all based on figures from NOAA, the US climate research body (National Oceanic and Atmospheric Administration).
NOAA statistics and reports
The Polarstern (translates as Pole Star), the research vessel belonging to the German polar agency AWI (Alfred Wegener Institute for Polar and Marine Research) returned to base after being the first research vessel to sail right round the north pole because the north-west passage was open as well as the north-east.
The Polarstern voyage around the North Pole
White ice and snow reflect heat back into the atmosphere. Water,open because the ice has melted, is darker and absorbs heat, warming the ocean further. The Arctic is heating up at an alarming rate.
“Rudy” sent a comment in to the Ice Blog. He still isn’t convinced about global warming, it seems. I’m still trying to understand how that can be and what his point of view is.
Rudy, forgive me for not publishing the comment, but it contains abridged quotes from people without the context. Without being able to check the context, I can’t put them up here.
I’m happy to pick up on some of your points, though.
You’re right. Thankfully, the Arctic was not ice-free in 2008.(I didn’t think it would be, neither did most reliable sources I follow). But sea-ice cover hit a record low in 2007 and is not recovering. The North-West passage has been open. And the warming trend is continuing. Changes in flora and fauna are being witnessed and recorded. This is happening. And things are changing fast.
You say winds and circulation are causes of sea-ice melting, not global warming. Sure, winds and circulation play an important role. Nobody would dispute that. But these factors are all connected. And the climate is changing. I’ve talked to scientists from all over the world who are desperately trying to make predictions for the future. Nobody has a crystal ball. But we know humankind is pumping masses of CO2 into the atmosphere, melting permafrost is releasing methane, an even more powerful greenhouse gas, into the atmosphere at an increasing rate. Of course there are natural climate cycles. But we are having our own effect.
I was talking to some British friends this weekend, who suggested we should really get away from the misleading “global warming” talk and refer to “climate change”. Apart from the jokes about the British wanting warmer weather anyway – of course climate change manifests itself in colder weather in some places at some times. Is it just the “global warming” term that bothers you?
What bothers me right now is that our EU countries are thinking about reducing their commitment to climate-saving measures because of the global financial crisis. If we don’t take action now, we might not have a globe we can live on, let alone finances to worry about.
I wish someone could convince me that’s too pessimistic?
Back on the Blog
The only Arctic areas I’ve seen in the last few weeks have been from the air.
(Doesn’t this remind you of a dino in the snow?)
Exactly one month since the last entry, I’m back at my desk in Deutsche Welle in Bonn and raring to blog.I’ve been in the USA during an interesting time, with the election campaign in full swing – and climate change high on the agenda. People are finally accepting that global warming is not just a figment of somebody’s imagination.
(Pools forming from melting snow in the Arctic).
It’s interesting to see both candidates falling over each other to be the one to save the planet from global warming. With oil prices as they are, the debate over opening protected areas, like the Arctic Wildlife Refuge, for oil exploration,has been a real eye-opener. At the beginning of my trip, Republican contender John McCain was still opposing offshore drilling. During it, he changed his mind and approved President Bush’s decision to lift the ban, supposedly to make more oil available and have an impact on prices. It seems to me the only likely impact is to appeal to any gullible, undecided voters, who might be fooled into thinking this is the way to give them cheap gas.
Barack Obama stood firm in opposing further offshore drilling. And his fellow Democrat Al Gore issued a challenge to the nation to make a complete shift away from fossil fuels to renewable energy within 10 years. Well, that is, indeed, an ambitious goal, but then – as Gore said – so was putting a man on the moon. Where there’s a (political) will, there’s a way.
One of the interesting things I came across while travelling in the US state of Washington was the Western Climate Initiative, a group of North American states seeking ways of reducing emissions. It shows that a lot can be done at regional level, even if there is a national government which refused to sign Kyoto or introduce binding emissions targets.
More info on the Climate Alliance of US and Canadian states
If anyone living in a country with a “developing economy” and working on a local sustainable energy project is reading this, by the way, you might be interested in applying for an award. You’ll find the details here:
Global Green Energy Awards 2008
During a conference at Stanford University in California, I felt the effect of the forest fires, creating smog over the whole area. In fact smoke from forest fires is being measured even in the remote areas of the Arctic. One measuring station is in Barrow, which I visited just last month:
The other is on Svalbard, in the Norwegian Arctic, which I visited for a programme last year, as part of our National Science Foundation-funded international radio collaboration to mark the International Polar Year:
More Arctic and Climate News from the NSF
Picture Gallery from Ny Alesund, Svalbard
I found it a bit bizarre to read this morning that there is something like a positive side-effect of all this: it could temporarily reduce the melting rate of the Arctic’s ice, because less solar radiation gets through. Researchers from the University of Colorado and NOAA are analyzing how smoke influences the Arctic climate relative to the amount of snow and ice cover.
Read a summary on the website, CIRES and University of Colorado
One of the big topics at the conference I was attending at Stanford a month ago was how climate change will result in increasing migration, with people forced to move to escape flooding, drought or extreme temperatures and weather conditions. I was interested to read today that there are some optimists who see climate change not only as a huge threat to the planet, but also as an opportunity to turn politics into “collective action” – by including ALL countries in tackling the challenge, not just the rich.
I’ll sign off today with that piece of food for thought. Here’s the link to the article. (Go on, it’s a shortie, I promise).
Climate Change as an Opportunity for Cosmopolitan Action? (By Ulrich Beck)
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