Category Archives: Climate

Climate Update : Science behind the big freeze: is climate change bringing the Arctic to Europe?

Jessop recovered the gold from the sunken HMS ...

Image via Wikipedia

A dramatic loss of sea ice covering the Barents and Kara Seas above northern Russia could explain why a chill Arctic wind has engulfed much of Europe and killed 221 people over the past week. The Independent reports | https://twitter.com/#!/LearnFromNature

The death toll from Arctic blast has been particularly severe in the Ukraine, where many of the dead have been people sleeping on the streets. Heating and food tents have been set up to ease their hardship. In Romania 24 people are known to have died and 17 in Poland.

A growing number of experts believe complex wind patterns are being changed because melting Arctic sea ice has exposed huge swaths of normally frozen ocean to the atmosphere above.

In particular, the loss of Arctic sea ice could be influencing the development of high-pressure weather systems over northern Russia, which bring very cold winds from the Arctic and Siberia to Western Europe and the British Isles, the scientists believe. An intense anticyclone over north-west Russia is behind the bitterly cold easterly winds that have swept across Europe and some climate scientists say the lack of Arctic sea ice brought about by global warming is responsible.

“The current weather pattern fits earlier predictions of computer models for how the atmosphere responds to the loss of sea ice due to global warming,” said Professor Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research. “The ice-free areas of the ocean act like a heater as the water is warmer than the Arctic air above it. This favours the formation of a high-pressure system near the Barents Sea, which steers cold air into Europe.”

Sea ice covering the Barents and Kara Seas has been exceptionally low this winter, according to the US National Snow and Ice Data Centre in Boulder, Colorado. But air temperatures above the Barents and Kara Seas have been higher than average. The relatively mild westerly winds that have kept Britain from freezing much of this winter have been blocked by fierce high pressure over north-west Russia, centred on an area just south of the Barents Sea.

Studies by scientists at the Alfred Wegener Institute for Polar and Marine Research have confirmed a link between the loss of Arctic sea ice and the development of high-pressure zones in the polar region, which influence wind patterns at lower latitudes further south. Scientists found that as the cap of sea ice is removed from the ocean, huge amounts of heat are released from the sea into the colder air above, causing the air to rise. Rising air destabilises the atmosphere and alters the difference in air pressure between the Arctic and more southerly regions, changing wind patterns.

Professor Rahmstorf said the Alfred Wegener study confirms earlier predictions from computer models by Vladimir Petoukhov of the Potsdam Institute, who forecast colder winters in western Europe as a result of melting sea ice.

Dr Petoukhov and his colleague Vladimir Semenov were among the first scientists to suggest a link between the loss of sea ice and colder winters in Europe. Their 2009 study simulated the effects of disappearing sea ice and found that for some years to come the loss will increase the chances of colder winters.

“Whoever thinks that the shrinking of some far-away sea ice won’t bother him could be wrong. There are complex interconnections in the climate system, and in the Barents-Kara Sea we might have discovered a powerful feedback mechanism,” Dr Petoukhov said.

But UK climate researcher Adam Scaife said other complexities are almost certainly influencing the current cold spell. “There is a pretty clear link between the current event and the upper level winds… The winds up at 30km (18.6 miles) altitude are very weak,” he said. “We have verified several times using computer model experiments that this leads to high pressure across northern Europe and cold winter conditions in the UK as we see now.”

Big chill: UK outlook

Today

Freezing overnight temperatures – expected to rival the -11.3C at Spennybridge in Powys yesterday – will ease but be followed in western parts by afternoon snow. This will be replaced by rain in the evening, but as temperatures plunge it will turn to ice, making driving treacherous. Snow will sweep across the country reaching the east by tonight.

Tomorrow

Eastern regions will wake up to snow, with the Met Office expecting up to four inches in some areas. Temperatures across the country are unlikely to get above 1C or 2C.

Next week

Slightly warmer but still likely to be below the average maximum of 6C and average minimum of 1C for the time of year.

Lewis Smith

Source : http://www.independent.co.uk/news/science/science-behind-the-big-freeze-is-climate-change-bringing-the-arctic-to-europe-6358928.html

Climate change : Journal editor resigns over ‘flawed’ paper co-authored by sceptic

Mean surface temperature change for the period...

Image via Wikipedia

From The Independent The editor-in-chief of a climate science journal has resigned in response to an academic controversy triggered by his publication of a paper co-authored by a leading climate sceptic.

Prof Wolfgang Wagner wrote in an editorial published on Friday in Remote Sensing that he felt obliged to resign because it was now apparent to him that a paper entitled On the misdiagnosis of surface temperature feedbacks from variations in Earth’s radiant energy balanceby Roy Spencer and Danny Braswell, was “fundamentally flawed and therefore wrongly accepted by the journal”. Spencer has frequently appeared in the rightwing media in the US criticising “climate alarmism” and is the author of a book called The Great Global Warming Blunder.

Paper : http://www.mdpi.com/2072-4292/3/9/2002/pdf

Wagner, who is the head of the Institute of Photogrammetry and Remote Sensing at the Vienna University of Technology, added he “would also like to personally protest against how the authors and like-minded climate sceptics have much exaggerated the paper’s conclusions in public statements”.

Wagner specifically referred to headlines such as “New NASA Data Blow Gaping Hole In Global Warming Alarmism” on the Forbes magazine website and “Does NASA data show global warming lost in space?” on Foxnews.com, which both attracted considerable attention online.

The paper in question – which, Wagner says, was downloaded 56,000 times within one month after its publication in July, as a result of the attention it attracted – purported to show how the Earth’s atmosphere is more efficient at releasing energy into space than is programmed into the computer models used to forecast climate change.

“Satellites show energy being lost while climate models show energy still being gained,” Spencer said at the time of publication. The University of Alabama, where Spencer works as a principal research scientist at the Earth System Science Center, added in a press release in July: “The natural ebb and flow of clouds, solar radiation, heat rising from the oceans and a myriad of other factors added to the different time lags in which they impact the atmosphere might make it impossible to isolate or accurately identify which piece of Earth’s changing climate is feedback from man-made greenhouse gases.”

But Wagner says he now accepts the subsequent criticism from other climate scientists that the peer-review process used to test the paper’s findings was flawed. “As the case presents itself now, the [peer review] editorial team unintentionally selected three reviewers who probably share some climate sceptic notions of the authors … The problem is that comparable studies published by other authors have already been refuted in open discussions and to some extend also in the literature, a fact which was ignored by Spencer and Braswell in their paper and, unfortunately, not picked up by the reviewers. In other words, the problem I see with the paper by Spencer and Braswell is not that it declared a minority view (which was later unfortunately much exaggerated by the public media) but that it essentially ignored the scientific arguments of its opponents. This latter point was missed in the review process, explaining why I perceive this paper to be fundamentally flawed and therefore wrongly accepted by the journal.”

Spencer is no stranger to academic controversies. He has long maintained that satellite observations showed that atmospheric temperatures were cooling rather than warming until it was shown that the satellites in question suffered from “orbital drift”.

John Abraham, an associate professor at the University of St Thomas’s school of engineering in Minnesota who criticised the Spencer paper upon its publication, told the Guardian: “It is remarkable that an editor-in-chief has stepped down from his role at a journal because of the publication of a flawed paper. This significant event reflects on the significance of the flaws in the paper and its review process. It is commendable that Wagner has reacted responsibly to the situation.”

He continued: “Spencer and his colleagues have a long history of minimising the effects of human-caused climate change; they also have a long history of making serious technical errors. This latest paper is only one in a decade-long track record of errors that have forced Spencer to revise his work as the errors are brought to light. Spencer is well known in the scientific community for publishing high-profile papers that initially dispute global warming and only later are found to be faulty.

“This latest article reportedly showed that the climate is not as sensitive to increases in greenhouse gases. It also called into question the cause-and-effect relationship between clouds and climate change. Wolfgang’s resignation was based on the quality of the review the paper received and the obvious technical errors which the paper contained.”

Next week, Prof Andrew Dessler of the department of atmospheric sciences at Texas A&M University, is due to publish a paper in the journal Geophysical Research Letters offering a detailed peer-reviewed rebuttal of Spencer’s paper.

Spencer responded to the resignation via his blog. He said: “I want to state that I firmly stand behind everything that was written in that paper … It appears the IPCC [Intergovernmental Panel on Climate Change] gatekeepers have once again put pressure on a journal for daring to publish anything that might hurt the IPCC’s politically immovable position that climate change is almost entirely human-caused. I can see no other explanation for an editor resigning in such a situation.”

Climate update : Is climate change to blame for famine in the Horn of Africa?

It’s impossible, says Duncan Green of The Guardian, to answer with a simple yes or no – but here’s a summary of what we think we know so far

So is famine in the Horn of Africa linked to climate change or not? The question arises whenever “extreme weather events” – hurricanes, floods, droughts – hit our TV screens. It’s impossible to answer with a simple yes or no – but here’s what we think we know so far.

 

The current drought conditions have been caused by successive seasons with very low rainfall. Over the past year, the eastern Horn of Africa has experienced two consecutive failed rainy seasons. According to surveys of local communities, this is part of a long-term shift. Borana communities in Ethiopia report that whereas droughts were recorded every six to eight years in the past, they now occur every one to two years.

Meteorological data back up the picture on temperatures: mean annual temperatures increased from 1960-2006 by 1C in Kenya and 1.3C in Ethiopia, and the frequency of hot days is increasing in both countries. Rainfall trends are less clear: according to the Intergovernmental Panel on Climate Change’s Fourth Assessment Report, there are no statistically significant trends in rainfall. However, more recent research suggests that rainfall decreased from 1980 to 2009 during the “long-rains” (March to June).

The historical record does not “prove” that the current drought is directly attributable to climate change. True, there are now a few cases in which scientists have been able to estimate the extent to which man-made climate change has made a particular extreme weather event more likely, but these exercises require reliable long-term weather data that only exists for Europe and North America – no such studies as yet exist in the case of the current drought.

What about the future? Globally, climate change modelling projects an increase in the frequency and severity of extreme weather events like droughts and floods. In the absence of urgent action to slash global greenhouse gas emissions, temperatures in the region will probably increase by 3C-4C by 2080-99 relative to 1980-99.

But again, rainfall projections are unclear. Most modelling, as reflected in the IPCC’s last assessment, suggests more rain will fall in the east Africa region as a whole, with an increase in “heavy events” (sudden downpours, so more flood risk). However, some recent studies suggest rainfall will decrease, particularly in the long rains.

The combination of higher temperatures and more unpredictable rains is alarming for food production. One recent estimate published by the Royal Society suggests much of east Africa could suffer a decline in the length of the growing period for key crops of up to 20% by the end of the century, with the productivity of beans falling by nearly 50%.

The conclusion? Attributing the current drought directly to climate change is impossible, but in the words of Sir John Beddington, the UK government’s chief scientific adviser, in a talk at Oxfam last week, “worldwide, events like this have a higher probability of occurring as a result of climate change”. Moreover, unless something is done, the current suffering offers a grim foretaste of the future – temperatures in east Africa are going to rise and rainfall patterns will change, making a bad situation worse.

What to do? First, remember that while the drought is caused by lack of rainfall, famine is man-made. As the Nobel prize-winning economist Amartya Sen famously observed, famines do not occur in functioning democracies. The difference between the minor disruption of hosepipe bans and the misery in the Horn is down to a failure of politics and leadership. It is no accident that the communities worst affected by the drought are not just those blighted by conflict but also by decades of official neglect and contempt from governments, which see pastoralism as an unwanted relic of the past.

Second, the famine shows the extreme vulnerability of poor people to weather events like failed rains. Governments and the international community have to save lives now, but also act to reduce that chronic vulnerability, building local ability to manage the drought cycle, improving the flow of data, information and ideas for adapting to climate change, and drastically increasing long-term investment in smallholder agriculture and pastoralism, which have shown they can provide a decent life for millions of east Africans, provided they are supported (rather than ignored) by governments.

Beyond helping east Africa and other vulnerable regions adapt to impending climate change, it is of course also incumbent on the rich and emerging economies to cut the greenhouse gas emissions that cause it. Fail to do that, and all attempts at adaptation are likely to offer only temporary relief.

• Oxfam last week published a briefing on climate change and drought in east Africa

Climate change update : Himalayan glaciers shrinking

Mount Everest from Kalapatthar.

Image via Wikipedia

 

Japanese researchers say three glaciers have shrunk over the past 40 years due to climate change and two may disappear altogether. Reuters reports via The Guardian. 

Three Himalayan glaciers have been shrinking over the past 40 years due to global warming and two of them, located in humid regions and on lower altitudes in central and east Nepal, may disappear in the future, researchers in Japan said on Tuesday.

Using global positioning system and simulation models, they found that the shrinkage of two of the glaciers – Yala in central and AX010 in eastern Nepal – had accelerated in the past 10 years compared with the 1970s and 1980s.

Yala’s mass shrank by 0.8 (2.6 feet) and AX010 by 0.81 metres respectively per year in the 2000s, up from 0.68 and 0.72m per year between 1970 and 1990, said Koji Fujita at the Graduate School of Environmental Studies in Nagoya University in Japan.

“For Yala and AX, these regions showed significant warming … that’s why the rate of shrinking was accelerated,” Fujita told Reuters by telephone. “Yala and AX will disappear but we are not sure when. To know when, we have to calculate using another simulation (model) and take into account the glacial flow,” Fujita said, but added that his team did not have the data to do so at the moment.

Their findings were published in the journal Proceedings of the National Academy of Sciences on Tuesday.

The Himalayas is an enormous mountain range consisting of about 15,000 glaciers and some of the world’s highest peaks, including the 8,848m-high Mount Everest and K2.

Apart from climate change and humidity, elevation also appears to play a critical role in the lifespan of glaciers, which are large persistent bodies of ice.

The Rikha Samba glacier in the drier region of west Nepal has also been getting smaller since the 1970s, but its rate of shrinking slowed to 0.48m per year in the past 10 years compared to 0.57m per year in the 1970s and 1980s.

This was because the 5,700m-high glacier was located on a higher altitude, which meant that losses in mass from melting could be compensated at least partly by collection of snowfall, Fujita said.

“In the case of Yala and AX, they are situated on lower elevation (altitudes), therefore shrinkage was accelerated. Glaciers that have no chance to get snow mass will eventually disappear,” Fujita said.

Climate change : Could kill one in 10 species by end of the century!

Proportion responding that global warming is a...

Image via Wikipedia

Climate change is speeding up the rate at which animals and plants are becoming extinct. By the end of the century, one in 10 species could be on the verge of extinction because of the effects of global warming, a study has found.

The findings support the view that the earth is currently experiencing a global mass extinction where the rate at which species are being lost is many times greater than the historical extinction rate. It is the sixth great mass extinction in the history of life on earth. Scientists said that previous predictions of how fast species are being lost because of climate change match the actual observed losses. They calculate that around 10 per cent of species alive today could be facing extinction by 2100.

Ilya Maclean and Robert Wilson, of the University of Exeter, examined nearly 200 previous predictions about how climate change may affect the extinction of species and compared them with about 130 reports of changes already observed.

The aim was to judge the accuracy of estimates made by scientists in the past about climate change predictions in relation to species extinction. They concluded that the observed threats matched well with the actual threats, based on real observations.

“We tried to see whether predictions were backed up by things that have already happened and this was what we found,” Dr Maclean said.

Rising temperatures, changing patterns of rainfall and increasing acidity of the oceans are all having an impact on the viability of vulnerable species. In the oceans, for instance, rising acidity threatens the survival of the polyp organisms that make coral reefs while increasing temperatures are sending some mountain species of plants and animals to higher altitudes.

“Our study is a wake-up call for action. The many species that are already declining could become extinct if things continue as they are. It is time to stop using the uncertainties as an excuse for not acting. Our research shows that the harmful effects of climate change are already happening and, if anything, exceed predictions,” Dr Maclean said.

“The implications are that unless we do something to reverse climate change impacts by lowering levels of carbon dioxide, or help species cope with climate change, we could be looking at a lot of extinctions by the end of the century. It’s further evidence that we are experiencing a global mass extinction,” he said.

The study, published in the journal Proceedings of the National Academy of Sciences, found that global warming ranks alongside habitat loss and invasive species as a major threat to endangered animals and plants. It concluded that the speed at which the climate is likely to change in the future threatens to overwhelm the rate at which species are able to adapt.

“By looking at such a range of studies from around the world, we found that the impacts of climate change can be felt everywhere, and among all groups of animals and plants,” said Robert Wilson, the study’s co-author.

“From birds to worms to marine mammals, from high mountain ranges to jungles and to the oceans, scientists seem to have been right that climate change is a real threat,” Dr Wilson said. “We need to act now. This means cutting carbon emissions and protecting species from the other threats they face, such as habitat loss and pollution.”

Follow

Get every new post delivered to your Inbox.

Join 9,198 other followers

%d bloggers like this: