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Posted: 02-04-2013 07:31 Post subject:

Melt may explain Antarctica's sea ice expansion

Climate change is expanding Antarctica's sea ice, according to a scientific study in the journal Nature Geoscience.
The paradoxical phenomenon is thought to be caused by relatively cold plumes of fresh water derived from melting beneath the Antarctic ice shelves.

This melt water has a relatively low density, so it accumulates in the top layer of the ocean.
The cool surface waters then re-freeze more easily during Autumn and Winter.
This explains the observed peak in sea ice during these seasons, a team from the Royal Netherlands Meteorological Institute (KNMI) in De Bilt says in its peer-reviewed paper.

Climate scientists have been intrigued by observations that Antarctic sea ice shows a small but statistically significant expansion of about 1.9% per decade since 1985, while sea ice in the Arctic has been shrinking over past decades.

The researchers from the KNMI suggest the "negative feedback" effect outlined in their study is expected to continue into the future.
They tried to reproduce the observed changes in a computer-based climate model.
The sea ice expanded during Southern Hemisphere autumn and winter in response to the development of this fresh, cool surface layer, which floated on the denser, warmer salty sea water below.

This fresh water is ultimately derived from enhanced melting at the base of the Antarctic ice shelves.
"Sea ice around Antarctica is increasing despite the warming global climate," said the study's lead author Richard Bintanja, from the KNMI.
"This is caused by melting of the ice sheets from below," he told the Reuters news agency.

But there are other plausible explanations for Antarctic sea-ice expansion.
Paul Holland of the British Antarctic Survey (BAS) stuck to his findings last year that a shift in winds linked to climate change was blowing ice away from the coast, allowing exposed water in some areas to freeze and make yet more ice.
"The possibility remains that the real increase is the sum of wind-driven and melt water-driven effects, of course. That would be my best guess, with the melt water effect being the smaller of the two," he told the London Science Media Centre.

The study in Nature Geoscience also asserts that the cool melt water layer may limit the amount of water sucked from the oceans that falls as snow on Antarctica. Cold air can hold less moisture than warm air.

http://www.bbc.co.uk/news/science-environment-21991487

Posted: 11-05-2013 07:52 Post subject:

Climate change shifts migrating birds' wintering ground
By Victoria Gill, Science reporter, BBC News

Three species of migratory duck have shifted their wintering grounds northward in response to increasing temperatures, say scientists.
The birds - the tufted duck, goosander and goldeneye - are common in Britain and Ireland during northern Europe's winter.
But their numbers in these countries have shrunk in the last 30 years.

According to the findings, published in the journal Global Change Biology, many now stop short on their annual journey.
Gathering and analysing data from the three-decade-long International Waterbird Census, the researchers found many birds were staying closer to their summer breeding grounds all year round.
At the northern end of their migratory flyway, in Sweden and Finland, there were approximately 130,000 more of the ducks in 2010 than in 1980.
On the southern end - in Britain, France, Ireland and Switzerland - numbers have dropped by about the same amount.

According to Richard Hearn from the Wildfowl and Wetlands Trust (WWT), who was involved in the study, this represented a loss of between 45 and 60% of the population in Britain and Ireland.
"It makes more sense for the birds, because they don't have to embark on that very energy-intensive journey," he explained.

This "huge" shift he said was caused by increasingly warmer European winters. The researchers drew this conclusion by examining temperature data gathered from the same areas of Europe over the last three decades.
"Early winter temperature in south Finland," Dr Hearn said, "increased by about 3.8C between 1980 and 2010."

This shift in migration is known as "short-stopping", whereby Arctic-breeding species that head to milder climates for the winter find they no longer need to travel so far for the unfrozen lakes that allow them to find food.
"This may have implications for their conservation, because birds are making less use of the areas that were designated to protect them," said Dr Hearn.

He added that the findings were a warning sign of the implications of a warming climate.
"These northern shifts can't go on forever, because the birds will simply run out of habitat," he said.

Andy Musgrove, head of monitoring at the British Trust for Ornithology, said this was "an important paper" adding to a growing body of evidence concerning the response of wildlife to a changing climate.
"All species are adapted to live in particular environments and when conditions change, then species will respond if they can," he said.

"What is interesting with migratory birds is how rapidly they are able to change their distributions, as a result of their ability to cover long distances to find suitable conditions.
"It is likely that the decline in UK wintering numbers of goldeneye, for example, is linked to the increase in Scandinavia.

"This is not always the case however, and for other species such as Bewick's swan and velvet scoter, it looks like declines in the UK are matched by those elsewhere across Europe.
"Such different cases really emphasise the importance of international cooperation in the monitoring of birds and other wildlife."

http://www.bbc.co.uk/news/science-environment-22484907

Posted: 14-05-2013 19:46 Post subject:

Sea levels are rising - but how quickly?

Scientists are warning that the level of the sea may rise by slightly more than previously forecast - but they also say that the very worst predictions look much less likely.
Confused? If so, you're not alone.

The future of sea level rise is one of the most important questions in climate science because so many millions around the world live beside coasts - but it's also one of the most difficult to answer.

One of the authors of a new study, published today, even described the uncertainties of the field with that memorable phrase first coined by the former US defence secretary Donald Rumsfeld: "unknown unknowns". Cool

Not everyone is always so open about this.
I'll never forget a video screened at the opening session of the UN's climate talks in Copenhagen in 2009 - the conference that got nowhere - which portrayed this issue at its most simplistic.
One scene showed a vast flood that left a little girl hanging from a tree screaming her heart out.
The message to delegates was crude: "If you don't negotiate a climate deal, the kid gets it".

I reported at the time that nothing in the scientific literature was specific enough to justify this lurid threat.
In the event, none of the major players was paying attention to this climate horror show anyway and there was no treaty.

So what did the science say back then and what does it say now?

The last major report by the UN's Intergovernmental Panel on Climate Change (IPCC), its Fourth Assessment Report published in 2007, concluded that the global average level of the sea may rise by between 18cm-59cm.

Much of that was expected to come from what's called "thermal expansion" - the physical process by which the volume of a body of water expands as it warms, as the oceans are.

But, crucially, the IPCC said that not enough was known about the other great potential contributor to sea level rise - the melting of the polar ice sheets and glaciers.

Polar melting has been a kind of wild card in these calculations: a sudden acceleration in melting could cross some hidden threshold and trigger runaway melting that would cause an unexpected surge. Or not.

To try to fill that gap in the knowledge, a leading British polar researcher, Professor David Vaughan of the British Antarctic Survey, and teams of colleagues came together in a consortium called Ice2sea.

So what does the new study tell us? The headline is that forecasts of the changes to the ice-sheets and glaciers in the Arctic and Antarctic suggest their melting could contribute between 3cm-36cm to sea level rise.
This would add another 10cm to the upper range of the last IPCC forecast.

This perhaps does not sound like much of a change - and the range in numbers is still pretty large spanning from "not very much at all" to "quite a bit".

But Prof Vaughan and others say the estimate is much more robust than earlier ones and provides more clarity for policy-makers.

In any case a rise on slightly larger bigger scale would of course be serious for communities in low-lying countries. I saw for myself how most the tiny island nation of Tuvalu is already only 2-3m above sea-level.

The challenge with all forecasts - especially on this question - is that they rely on a whole series of factors and assumptions.

The Ice2sea researchers started with a global climate model that assumed a particular scenario for the rise in greenhouse gases. It then used further models to investigate the potential change in climate in regions such as Greenland and Antarctica.

Another layer of computer simulations explored how the ice might respond. Final stages investigated what that could mean for sea level not just globally but also on particular coasts.
Hence the large range of possible outcomes.

On top of that, the ice-sheets and glaciers themselves are often inaccessible and hard to measure. One research effort even involved firing hi-tech javelins at a glacier in Antarctica.
And satellite data only stretches back a few decades.

Interestingly, one conclusion is that the very scariest scenarios look less likely.
There is only a one in 20 chance, they reckon, that by 2100 coastal towns in the Thames Estuary, Holland and Ireland may get hit by extreme surges about one metre higher than now.

At a media briefing, I asked what that meant and whether we could take it that there's a 95% chance that this won't be what happens. That's right, I'm told. The very gloomiest warnings look far less plausible.

The most certain piece of knowledge is that the global average sea level has been rising by about 3mm a year.
But what really matters is whether this will accelerate - and by how much. And all that's still a work in progress.

http://www.bbc.co.uk/news/science-environment-22531949

"There is only a one in 20 chance, they reckon, that by 2100 coastal towns in the Thames Estuary, Holland and Ireland may get hit by extreme surges about one metre higher than now."
Given the density of the poulation in those areas, that sounds like a pretty high risk to me.

As with assessing the risks of an asteroid impact, you really need to factor the number of lives at risk in any particular scenario.

Posted: 03-06-2013 09:41 Post subject:

Ed Davey attacks 'blinkered' climate change sceptics
By Roger Harrabin, Environment analyst

Energy Secretary Ed Davey is to make an unprecedented attack later on climate change sceptics.
In a speech, the Lib Dem minister will complain that right-wing newspapers are undermining science for political ends.
He is set to accuses climate sceptics of nimbyism, publicity-seeking, and "blinkered... bloody-mindedness".

It comes ahead of a crucial Energy Bill vote, during which Mr Davey will be accused by backbenchers of betraying his party's green credentials.
Mr Davey gave way last year to demands from the chancellor to drop a commitment in the bill for almost all electricity to be generated from low-carbon sources like wind and nuclear by 2030.

The Chancellor insisted that a decision on 2030 should be delayed until 2016 at the earliest (after the election) but many Lib Dem and Conservative MPs are expected to join Labour in voting for an amendment to introduce the target immediately.
Mr Davey claims the bill will still prompt a major change in the way power is generated.
His colleagues will suspect that his speech on climate sceptics and the media is a way of bolstering his party’s credibility on the issue.

The speech is an explosion of anger from a politician who has long been privately frustrated about the extent to which right-wing newspapers have swung Conservative back-benchers behind the climate sceptic cause.
He believes editors are corrupting public understanding of science and making it more difficult to impose measures to tackle the emissions that are disrupting the climate.

Last week, for instance, the green-minded Tory MP Tim Yeo, who has laid the amendment calling for 2030 targets, was "outed" as a closet climate sceptic after saying there was a chance that climate change could be natural.
Mr Yeo insists that he went on to say that the overwhelming consensus is that climate change is man-made, but this crucial fact was drowned out.

Meanwhile, a newsletter from Lord Lawson’s Global Warming Policy Foundation trumpeted: "We are all climate sceptics now." Rolling Eyes

Mr Davey says climate change is being turned into a political football.
In a draft of his speech, he says: "Of course there will always be uncertainties within climate science and the need for research to continue.
"But some sections of the press are giving an uncritical campaigning platform to individuals and lobby groups.
"This is not the serious science of challenging, checking and probing.
"This is destructive and loudly clamouring scepticism born of vested interest, nimbyism, publicity seeking contraversialism or sheer blinkered, dogmatic, political bloody-mindedness.

"This tendency will seize upon the normal expression of scientific uncertainty and portray it as proof that all climate change policy is hopelessly misguided.
"By selectively misreading the evidence, they seek to suggest that climate change has stopped so we can all relax and burn all the dirty fuel we want without a care.
"Those who argue against all the actions we are taking to reduce emissions, without any serious and viable alternative, are asking us to take a massive gamble with the planet our children will inherit, in the face of all the evidence, against overwhelming odds."

The speech at a Met Office event in London takes place as 55 organisations from green groups to manufacturing bodies issued a joint statement calling on MPs to vote in favour of the 2030 decarbonisation amendment.
It says: "We represent different parts of society but are united in the belief that the Energy Bill represents a major opportunity to put the UK firmly on track to becoming a world leading low-carbon economy, boost employment and show genuine leadership in the fight against dangerous climate change."

The list of signatories includes SSE electricity, the Royal Society of Arts and Commerce; Dong Energy; Renewable UK; the Carbon Capture and Storage Association; the Solar Trade Association, the Renewable Energy Association; Business in the Community; the Church of Scotland; the National Farmers Union and the TUC.
An additional 50 organisations have also added their support.

The organisations believe that fixing a clean electricity target will drive investment in renewable industries that will create jobs and wealth in the UK.

Critics fear that the measure will make UK power prices uncompetitive and divert investment from other industries.
They say the UK should not commit itself to a "green" economy while there is no comprehensive global climate agreement obliging all nations to follow suit.

The chancellor thinks the UK’s energy future lies with an expansion of power from gas.

http://www.bbc.co.uk/news/science-environment-22745578

Posted: 03-06-2013 20:53 Post subject:

Spring will be coldest in 50 years, Met Office says

This spring is on track to be the coldest for more than 50 years, provisional Met Office figures suggest.

This month has seen lower than average temperatures and it has been wetter than usual, forecasters said.

http://www.bbc.co.uk/news/uk-22718944

Posted: 03-06-2013 22:21 Post subject:

Posted: 04-06-2013 20:28 Post subject:

Posted: 04-06-2013 20:49 Post subject:

I was obliquely referring to the comments of Lib-Dem Ed Davey, but I wasn't really talking politics.

When talking of Global warming, it's necessary to look at the figures world-wide over the long term. A cold spring over Britain signifies nothing in the wider picture - it's just a glitch in the jet-stream. Probably linked to all the extra rain they've had in central Europe that's caused all the flooding, although I haven't heard that from official sources...

Meanwhile, our fine weather is set to last into the w/e - but that signifies nothing in the long-term either!

Posted: 04-06-2013 20:49 Post subject:

Interesting thing about this idea that carbon dioxide causes runaway warming:

The atmosphere of Mars has a carbon dioxide concentration of 95.32% and methane concentration of 10.5 ppb, yet has a temperature range from -17.2 °C (1.0 °F) to -107 °C (-161 °F).

Shouldn't it be a lot warmer?

Yes...I do know that much warming on Earth is caused by volcanic action and the 'heat reservoir' action of the oceans...but we are led to believe that the CO2 is apparently what is causing runaway warming...even with a puny concentration of 0.0397%.

Confused

Posted: 04-06-2013 21:19 Post subject:

Posted: 17-06-2013 09:03 Post subject:

Climate change overseas likely to affect UK food supplies
By Roger Harrabin, Environment analyst

Climate change abroad will have a more immediate effect on the UK than climate change at home, a report says.
Research by consultants PWC for Defra says the UK is likely to be hit by increasingly volatile prices of many commodities as the climate is disrupted.

It warns that global production of some foodstuffs is concentrated in a few countries.
These are likely to suffer increasing episodes of extreme weather.

The report says there will be opportunities for the UK from climate change but these are likely to be far outweighed by problems.

The opportunities include the ability to export British know-how and reduced shipping costs if the Arctic becomes ice-free. The Arctic looks likely to be a big business opportunity; research estimates suggest that it is likely to attract more than £64bn of investments over the next decade.

The biggest threats are increased volatility in food prices and protectionist measures over food, like India's ban on selling rice.
"What's interesting is that threats from climate change overseas appear an order of magnitude higher than domestic threats," PWC's Richard Gledhill told BBC News.

"This doesn't just refer to the most vulnerable countries like the small island states... climate events in developed countries could damage the UK economy by impacting on food and other resources. We could also suffer damage to assets from events like the floods in central Europe or Superstorm Sandy; this all feeds back into the UK economy."
The report warns that as the climate changes, there will be pressure for the UK to increase its aid budgets (already under threat from back-bench Conservatives).

The report is a follow-up to the recent UK Government Climate Change Risk Assessment (CCRA) which assessed domestic threats and opportunities and the Foresight study into international climate change.
It is based on the UN's "medium CO2 emissions scenario" which is broadly aligned with the 2C maximum temperature increase - a target that is unlikely to be met. That means the study is on the optimistic side, it says.

The paper draws on research from Chatham House describing climate change as a multiplier of other threats.
"Already, price volatility of resources is the new normal," lead author Bernice Lee told BBC News.
"The political implications of this are strong for all countries. Environmental change, including water scarcity and extreme weather will continue to constrain production and transport of key resources and this only looks as though it will get worse."

http://www.bbc.co.uk/news/science-environment-22913559

Posted: 17-06-2013 09:28 Post subject:

Frigging climate change. Yesterday I got sunburnt from sitting outside for two or three hours, this morning I got drenched from a torrential downpour and hellacious thunderstorm... Evil or Very Mad

Posted: 24-06-2013 08:51 Post subject:

Another amusing Monday rant from from Boris:

The weather prophets should be chucked in the deep end
Homeowners lumbered with useless swimming pools know precisely who they should blame

By Boris Johnson

...

http://www.telegraph.co.uk/topics/weather/10138096/The-weather-prophets-should-be-chucked-in-the-deep-end.html?placement=mid2

Posted: 24-06-2013 10:29 Post subject:

Nice one Boris. yeay

Posted: 24-06-2013 10:56 Post subject:

Typical denialist strawman bullshit, however. We know he's not thick, so what's his game?