Global warming close to becoming irreversible: scientists


LONDON |
Tue Mar 27, 2012 5:05pm EDT

LONDON (Reuters) – The world is close to reaching tipping points that will make it irreversibly hotter, making this decade critical in efforts to contain global warming, scientists warned on Monday.

Scientific estimates differ but the world’s temperature looks set to rise by six degrees Celsius by 2100 if greenhouse gas emissions are allowed to rise uncontrollably.

As emissions grow, scientists say the world is close to reaching thresholds beyond which the effects on the global climate will be irreversible, such as the melting of polar ice sheets and loss of rainforests.

“This is the critical decade. If we don’t get the curves turned around this decade we will cross those lines,” said Will Steffen, executive director of the Australian National University’s climate change institute, speaking at a conference in London.

Despite this sense of urgency, a new global climate treaty forcing the world’s biggest polluters, such as the United States and China, to curb emissions will only be agreed on by 2015 – to enter into force in 2020.

” We are on the cusp of some big changes,” said Steffen. “We can … cap temperature rise at two degrees, or cross the threshold beyond which the system shifts to a much hotter state.”

TIPPING POINTS

For ice sheets – huge refrigerators that slow down the warming of the planet – the tipping point has probably already been passed, Steffen said. The West Antarctic ice sheet has shrunk over the last decade and the Greenland ice sheet has lost around 200 cubic km (48 cubic miles) a year since the 1990s.

Most climate estimates agree the Amazon rainforest will get drier as the planet warms. Mass tree deaths caused by drought have raised fears it is on the verge of a tipping point, when it will stop absorbing emissions and add to them instead.

Around 1.6 billion tonnes of carbon were lost in 2005 from the rainforest and 2.2 billion tonnes in 2010, which has undone about 10 years of carbon sink activity, Steffen said.

One of the most worrying and unknown thresholds is the Siberian permafrost, which stores frozen carbon in the soil away from the atmosphere.

“There is about 1,600 billion tonnes of carbon there – about twice the amount in the atmosphere today – and the northern high latitudes are experiencing the most severe temperature change of any part of the planet,” he said.

In a worst case scenario, 30 to 63 billion tonnes of carbon a year could be released by 2040, rising to 232 to 380 billion tonnes by 2100. This compares to around 10 billion tonnes of carbon released by fossil fuel use each year.

Increased CO2 in the atmosphere has also turned oceans more acidic as they absorb it. In the past 200 years, ocean acidification has happened at a speed not seen for around 60 million years, said Carol Turley at Plymouth Marine Laboratory.

This threatens coral reef development and could lead to the extinction of some species within decades, as well as to an increase in the number of predators.

As leading scientists, policy-makers and environment groups gathered at the “Planet Under Pressure” conference in London, opinions differed on what action to take this decade.

London School of Economics professor Anthony Giddens favors focusing on the fossil fuel industry, seeing as renewables only make up 1 percent of the global energy mix.

“We have enormous inertia within the world economy and should make much more effort to close down coal-fired power stations,” he said.

Oil giant Royal Dutch Shell favors working on technologies leading to negative emissions in the long run, like carbon capture on biomass and in land use, said Jeremy Bentham, the firm’s vice president of global business environment.

The conference runs through Thursday.

(This version of the story replaces CO2 with carbon in par 12)

(Editing by Alessandra Rizzo)

Article source: http://www.reuters.com/article/2012/03/27/us-climate-thresholds-idUSBRE82Q18720120327

Sunshine helps us weather bad news!

Our straight talking Lancashire lass takes a sideways look at the daily news.


By Sian Claire Owen on 26 Mar 2012

No comments

Sunflower

What an amazing March weekend, how wonderful was the weather? More please!

It’s helped soften the not-so-shocking news that a cool £250,000 could buy you an intimate dining experience with our Prime Minister so that he could influence national policy in favour of your company. If buying legislation was your bag. This practice has been widespread with other political parties (yes Labour, we’re looking at you!) but Cameron promised to do away with sleaze. Now it seems he’s King of the Political Gigolos!

Then there’s the annual North Korea nuclear fright fest, which happens with such predictable regularity that it fails to even raise an eyebrow. North Korea is like the fat bully in the playground, stamping their feet, stealing sweets and threatening to beat everyone up. With nuclear bombs. But they won’t, it’s all just hot air. Thank God. And as I mentioned, it’s glorious outside so for today I’m not going to care.

And closer to home we can look forward to the army dishing out petrol whilst the tanker drivers prepare go on strike over work and pay. Well, thanks to the beautiful weather I have a sunny outlook today. I always did like a man in uniform!

In other news, this weekend saw the Clash of the Reality TV Titans – BBC’s The Voice went head to head with ITV’s Britain’s Got Talent, and both managed to scoop massive ratings. Cowell won, naturally.

But perhaps the real winners were Jonathan and Charlotte. Seriously, get a piece of this audition action!

That performance gave this cynical old writer the goosebumps. If it was contrived, I don’t care. I’m already a HUGE fan – what great kids!

Golly, I really hope the good weather keeps up, I’m in a brilliant mood today! I hope you all are too.

Happy Monday!

See also:

  • Celebrity beach bodies: guess who’s who

Article source: http://www.ivillage.co.uk/sunshine-helps-us-weather-bad-news/146335

UK weather: Heatwave will end just in time for Easter holidays

  • High temperatures and dry weather set to stay until Friday with mercury hitting 21C today and 23 tomorrow
  • Forecasters predict temperatures will dip to 12C at weekend but with little chance of rain amid drought warnings

By
Phil Vinter

07:13 EST, 27 March 2012

|

11:48 EST, 27 March 2012

Good news for those who feared the weekend’s glorious weather would disappear as soon as it arrived – the beautiful sunshine is now expected to last until at least Friday.

The Met Office predicted highs of up to 21C across the country today and the mercury will hit 23 tomorrow – matching yesterday’s hottest day of the year so far.

But forecasters predict the the warm spell will end on Saturday – just in time for the school Easter holidays.

Although, despite temperatures dropping to 12, there is still little sign of any rain – prompting new drought warnings.Temperatures are likely to pick up mid-week, but only as high as 16C.

It comes after almost a week of unseasonably warm and sunny weather. Amazingly, rather than the south of England, it was the Scottish village of Aboyne, Aberdeenshire, which recorded the highest temperature of the year so far as the mercury hit 22.9.

Golden brown: Silhouetted palm trees at Mumbles in Swansea on Tuesday morning

Heat wave: Milly Jenkins, 19, left, and Jasmine Olivier, 18, right enjoy the hot weather on the beach in St Austell, Cornwall

Golden brown:  Left, silhouetted palm trees on Mumbles seafront in
Swansea on Tuesday morning give the scene a beautiful sepia hue;
Meanwhile, right, Milly Jenkins, 19, and Jasmine Olivier, 18, take a
splash around in the waves as the hot weather warms St Austell beach in
Cornwall

Sunning on the dock of the bay: Dawn over the sill waters of the small fishing village of Mumbles near Swansea. Temperatures are set to remain high until the weekend across the UK

Sunning on the dock of the bay: Dawn over the sill waters of the small fishing village of Mumbles near Swansea. Temperatures are set to remain high until the weekend across the UK

South of the border Otterbourne in
Hampshire was the warmest place on Monday, peaking at 21.4C, while
Porthmadog in Wales reached 21.1C. Meanwhile central London saw
temperatures of 19C.

The first working day of the week saw
Britain’s beaches and parks fill up with sun seekers as forecasters
said the heatwave was due to high pressure and breezes from north Africa
and the Mediterranean.

Clear blue skies with dry, sunny
weather is anticipated for most of the UK on Wednesday and Thursday.
Early mist and fog on Friday is expected to clear to make way for
another beautiful day. Only western parts of Scotland will see some less
enjoyable conditions in the shape of breezes and patchy drizzle.

But forecasters urged sun-worshippers to
make the most of it because by the weekend temperatures will be back to a
more seasonal average of 11-12C (51-53F).

They predict chilly starts followed by sunshine and highs of 21C in both the North and the South over the next few days.

Rebecca Sherwin, a Met Office forecaster, said: ‘The weather is reasonably unusual for this time of year.

‘We’ve
got high pressure sat over the UK at the moment, causing very settled
weather. It means the day warms up very quickly in the morning.’

The dry conditions meant fire
services across Scotland had to deal with a number of grass
fires and the Highlands Islands Fire Rescue department are warning people not to burn garden waste or rubbish.

But it wasn’t just people who lapped
up the hot weather. Daffodil the spring piglet enjoyed a snuffle around
the flowers at West Lodge Rural Centre in Desborough, Northants.

Basking in the warmth: New spring lambs watch a hot air balloon over County Durham during perfect weather conditions for flying in the crystal clear skies

Basking in the warmth: New spring lambs watch a hot air balloon over County Durham during perfect weather conditions for flying in the crystal clear skies

Hot and high: The unusually warm weather made for pleasant flying conditions

Hot and high: The unusually warm weather made for pleasant flying conditions

Daffodil and her siblings, Pinky and
Perky, were born last Monday and have been a star attraction at the centre, which attracted 12,000 visitors this weekend.

Farm manager Ryan Thompson, 36, said: ‘When people see the pigs they fall in love with them and want to take them home.

‘But when I show them 60-stone Boris to remind them what the piglets will become, they change their minds.’

Drinking time: This hot bird took dipped its head into a waterfall at Carshalton Pond in south London to get some respite from the hot weather

Drinking time: This hot bird dipped its head into a waterfall at
Carshalton Pond in south London to get some respite from the hot weather

Shower time: A sprinkler sprays water onto flowers at Waddon Pond in south London as Britain continue to enjoy warm weather with temperatures rising to over 20C (68 Fahrenheit)

Shower time: A sprinkler sprays water onto flowers at Waddon Pond in south London as Britain continue to enjoy warm weather with temperatures rising to over 20C (68 Fahrenheit)

Doggy paddle: Geese look on as a dog cools down in the waters of Waddon Pond in South London as the country continues to enjoy the unusually warm March weather

Doggy paddle: Geese look on as a dog cools down in the waters of Waddon Pond in South London as the country continues to enjoy the unusually warm March weather

Flower fun: Catriona Lodge, 24 from Edinburgh exercises on a glorious sunny day with hula hoops in daffodils on Bruntsfield Links in Edinburgh

Moonshadow: Due to the hot weather and clear skies stargazers in London were given a treat last night as the planet Venus was seen clearly above the crescent moon

Day and night: Catriona Lodge, 24, left, from Edinburgh exercises on a glorious sunny day with hula hoops in daffodils on Bruntsfield Links Edinburgh; Due to the hot weather and clear skies stargazers in London were given a treat last night as the planet Venus was seen clearly above the crescent moon, right

Soaking it up: A man looks at the beautiful scene at Waddon Park as the sun continues to shine

Soaking it up: A man looks at the beautiful scene at Waddon Park as the sun continues to shine

Heathrow too is expecting a lively
period. It anticipates that the next seven days will be the busiest of
the year with more than 1.6 million passengers expected to pass through
its doors in the first week of the Easter school holidays alone (Friday
30 March to Friday 6 April).

Friday March 30 is predicted to be
the airport’s busiest day with over 220,000 people heading home or
jetting abroad for last minute skiing or guaranteed sunshine over the
Easter weekend.

A total of 3.4 million passengers 
will pass through the five terminals during the two week school break
(30 March to 15 April) and additional staff are being rostered on to
help passengers, while dedicated family lanes and pre-flight play areas
will cater for the thousands of families flying this holiday.

There will be special appearances by
Peter Rabbit, chocolate Easter treats and activity books plus Kids Eat
Free deals in many of Heathrow’s restaurants.

While this weekend’s warm spell was good news for many, it will add to fears of droughts this summer.

Sand people: A young boy makes a sandcastle on the beach in Blyth, Northumberland

A young boy plays on the beach in Blyth, Northumberland, as Britons was due to enjoy another day of unseasonably warm weather after temperatures reached a new record

Sand people: A young boy and his mother make the most of the warm weather by playing on the beach in Blyth, Northumberland. While this weekend’s warm spell was good news for many, it will add to fears of droughts this summer

A not-so-distant shore: Early morning surfers make the most of the the warm weather in Llangennith, Gower near Swansea

A not-so-distant shore: Early morning surfers make the most of the the warm weather in Llangennith, Gower near Swansea

Making the most of it: Sun worshippers enjoy a day at the beach in Bournemouth

Making the most of it: Sun worshippers enjoy a day at the beach in Bournemouth

The dry weather has also caused some
major forest fires across the country with firefighters warning the
parched countryside is fast becoming a tinderbox waiting to explode into
flames.

In the latest incident, exhausted
crews said this morning the had won their fight to control flames
sweeping across the beautiful Ashdown Forest in Sussex.

More than fifty acres of woodland
ignited in the Kings Standing area near Brighton yesterday. It took
eight fire engines plus six Land Rovers from East Sussex Fire and Rescue
to tackle the blaze.

It broke out at around 1.45pm as hundreds of families descended on the forest to enjoy picnics and rambles.

Thick black smoke was seen rising from the woods where it’s feared countless birds’ nests have been destroyed.

With the spring breeding season in
full swing, eggs and chicks in the nests would have had no chance
against the advancing wall of flames.

The fire service is now warning people not
to light barbecues for picnics, throw away cigarette ends or even leave
bottles and glasses where they can magnify the sun’s rays.

The current hot weather has seen an
increasing number of woodland and heath fires – there was another huge
blaze near Poole in Dorset over the weekend.

Warning: Firefighters tackle a blaze in Barrackswood, Newport in what looks like a scene from a warzone after the heatwave caused hills to become tinder dry

Warning: Firefighters tackle a blaze in Barrackswood, Newport in what looks like a scene from a warzone after the heatwave caused hills to become tinder dry

Hampshire Police said two teenagers
were arrested after five acres of wildlife-rich heathland near
Fordingbridge went up in flames last week.

Meanwhile
thousands of fish are being removed from a stretch of water in
Cambridgeshire after water levels dropped significantly.

The
Environment Agency is rescuing fish from the 9km long Maxey Cut which
runs between Peterborough and Market Deeping in Lincolnshire.

The fish, which include chub, pike and sea trout, will then be released into the River Welland.
Low
rainfall and two dry winters in a row have caused ‘exceptionally low’
river flows, according to a spokesman for the Environment Agency.

David
Hawley, the agency’s northern area drought manager, said the area had
seen the lowest rainfall on record across Lincolnshire, Northamptonshire
and parts of Cambridgeshire over the last 16 months.

The rainfall for the period was 600mm to 200mm below average and Britain now faces the worst drought for 30 years.

‘The
Maxey Cut is already showing signs of environmental stress as a result
of the drought,’ he said.

‘Taking early action in a controlled manner is
better for the fish as they will be spawning in April and May. ‘

But this is how Britain and Ireland looked after snow hit last month. The image was taken February 7 by NASA's Modis satellite

Blue skies: This stunning high-resolution image of Britain and Ireland was taken at 1.30pm on Monday by NASA's Modis satellite

Then and now: These stunning Nasa images show that just seven weeks after Britain was covered in a white blanket of snow there are now clear blue skies and warm temperatures

Glorious day: Two girls enjoy a stroll in the beautiful sunshine in Bournemouth as temperatures soared well above the predicted 21C

Glorious day: Two girls enjoy a stroll in the beautiful sunshine in Bournemouth as temperatures soared well above the predicted 21C

But
it wasn’t all bad news.

The combination of soggy summer, mild winter
and recent warm weather will make this year’s display of spring
magnolias the most spectacular in living memory, say experts.

The trees are likely to be at their best over the next two or three weeks.

Colin
Crosbie of the Royal Horticultural Society gardens at Wisley, Surrey,
said: ‘We were lucky to have a wet warm summer which was great for bud
formation, followed by a mostly mild winter so the buds weren’t
damaged.’

And cherry blossom is blooming four weeks earlier in Britain this year thanks to the Spring heat wave.

The
unusually high temperatures of 21C have helped the beautiful pink and
white buds open more than a month early all over the country. The
spectacular blossom, which is usually associated with Easter, is already
brightening up fields, woodland edges, parks and gardens across the UK
after a week of sunshine.

Experts
believe the early blossom could even mean we are in for a bumper cherry
season as the fruit will have longer to mature and ripen.

Here’s what other readers have said. Why not add your thoughts,
or debate this issue live on our message boards.

The comments below have not been moderated.

Britain looks so lovely in the sunshine…..it is a very beautiful country. We are heading into autumn in Melbourne (which is also lovely) but there is something about the British spring which always makes me homesick…..

21-23° = heat wave !!!???

The DM seems to spend a lot of time in Bournemouth !

- RS, Switzerland, 27/3/2012 22:54+++++++++Why not just stop reading British newspapers? Or is there so little going on in Switzerland that you have no choice?

Palm trees, NZ cabbage trees, whatever, they look awful and provide nothing for our birds and insects. We have a temperate climate our native trees are beautiful and if anyone wants a reminder of sunnier places go and visit them and stop trying to change England into something it isn’t. After the last three bad winters I have been overjoyed to see these horrors have shrivelled up and died in a lot of gardens where people have been stupid enough to plant them.
- get out of the matrix, don’t watchTV it tells lies, google Holly Greig, EUSSR, 27/3/2012 21:59
Don’t be so rude, I and many have grown these with pleasure. Bet your garden is dull and un interesting.

Stop moaning and just enjoy

Drop everything and enjoy it while it lasts!

Far too many British women looking like the first two girls and not enough like the last two. The (lack of) fashion/class in Britain is frightening.

Brits always seem to exaggerate weather conditions. If the temperature goes above 20c it’s a “heatwave”. If it drops below 0c it’s a “deep freeze”. Just deal with it and stop boring us with your drama.

Here we go again, talking up the weather in the UK. I bit of sunshine and the Poms go berserk. The only reason why the tempreture is mild in the UK is that it has come up from the south, not because the UK is in right latitude to have normal tempretures of that level. Every place has some changes to the tempreture pattern, only last week the tempreture went down to 17c in Melbourne, but it soon went back to normal tempreture for this time of the year. Climate is generally dictated on what latitude the country is at. The further from the equator, the cold the place. So please don’t get carried away with this bit of sunshine.
- Dr Malcolm, Melbourne, 27/3/2012 22:10 – shut up Skip – you’re having our weather…rain…rain and more rain – luv a duck – hooroo skip.

The views expressed in the contents above are those of our users and do not necessarily reflect the views of MailOnline.

Article source: http://www.dailymail.co.uk/news/article-2121032/UK-weather-Heatwave-end-just-time-Easter-holidays.html?ITO=1490

US natgas futures hit 10-yr low on weather, supplies


Tue Mar 27, 2012 12:58pm EDT

* Front month sinks early to lowest since February 2002

* Mild late-week forecasts, record supplies weigh on prices

* Coming up: API oil inventory data on Tuesday

(Releads, adds quote, updates futures prices)

By Joe Silha

NEW YORK, March 27 (Reuters) – U.S. natural gas futures
dropped to a new 10-year low o n T uesday as milder Northeast and
Midwest weather forecasts and record high supplies continued to
weigh on prices despite recent signs that the market may be
tightening.

While a cool start to the week did stir some late season
heating demand, traders said gas prices have been on the
defensive this month, with production running at or near an
all-time peak, inventories still at a record high for this time
and early spring temperatures mostly slowing overall demand.

At 12:25 p.m. EDT (1625 GMT), front-month April gas futures
on the New York Mercantile Exchange were down 3.4 cents,
or 1.5 percent, at $2.192 per million British thermal units.

The contract, which expires on Wednesday, slid early to
$2.176, the lowest for the near month since February 2002.

“As we enter the (spring) shoulder season and start
injections early, there’s just no fundamental support for gas,”
said Teri Viswanath, analyst at BNP Paribas in New York.

“There are limitations on fuel switching, so there may be no
other way to balance (supply and demand) this summer unless we
make more cutbacks in production,” she said.

While high gas production, primarily from shale, has put
pressure on prices this year, recent steep declines in gas
drilling have stirred expectations that low prices might finally
force producers to slow record output.

Several producers have announced output cuts, but traders
said the reductions were not nearly enough to soak up much of
the excess supply, particularly with inventories set to start
the stock-building season at a record and likely to test storage
capacity limits later this summer.

Record supplies and a mild March have helped drive the
front-month contract down 16 percent so far this month, with
more downside possible unless weather demand picks up.

After some cool early-week weather, AccuWeather.com expects
temperatures in the Northeast and Midwest, key gas-consuming
regions, to mostly average above normal for the next 10 days,
with daytime highs frequently topping 60 degrees Fahrenheit (16
degrees Celsius).

RECORD PRODUCTION

Gas prices last week again failed to react to Baker Hughes
data showing the gas-directed rig count fell for the 11th
straight week to 652, its lowest level since May 2002 when there
were 640 rigs operating.

(Rig graphic: r.reuters.com/dyb62s)

But despite the steady decline in gas drilling, the slowdown
has yet to be reflected in pipeline flows, which are still
estimated to be at or near record high levels.

Traders were waiting to see if U.S. Energy Information
Administration data on Thursday will show gross natural gas
production in January fell for a second month.

In late February, the agency reported a slight drop for
December, the first measurable decline since well freeze offs
curbed output in January and February 2011.

Some analysts say the gas-directed rig count may have to
drop below 600 to reduce flowing supplies significantly, noting
the producer’s shift to higher-value oil and gas liquids plays
still produces plenty of associated gas that partly offsets any
reductions in pure dry gas output.

Most analysts do not expect any major slowdown in gas output
until later this year.

INVENTORY GLUT

U.S. Energy Information Administration data last week showed
that total gas inventories rose by 11 billion cubic feet to
2.380 trillion cubic feet, still a record high for this time.

The build was slightly above market expectations and came
about two weeks earlier than usual. It was the first time in
five years that storage registered a gain for that week.

The inventory surplus, now more than 50 percent above the
five-year average, should provide a hefty cushion to meet any
spikes in demand or storm-related disruptions in supply this
year. (Storage graphic: link.reuters.com/mup44s)

And the surplus is expected to grow further in Thursday’s
EIA report. Injection estimates range from 20 bcf to 58 bcf,
with most expecting a build in the mid-40s.

Stocks rose an adjusted 7 bcf for the same week last year,
while the five-year average for that week is an 8 bcf decline.

Storage is likely to finish the month at an all-time high of
about 2.45 tcf, more than 55 percent above normal and easily
beating the previous March 31 record of 2.148 tcf set in 1983.

Traders said the huge storage overhang could drive prices
lower this spring as seasonal weather demand fades, then
pressure prices again late in the April-through-October
stock-building season if storage caverns fill to capacity and
force more supply into a well-supplied market.

While cheap gas has slightly tightened the supply-demand
balance this year as manufacturers use more of the fuel and
utilities switch to gas from pricier coal to generate power,
most analysts agree it will be very difficult for prices to move
higher until production shows concrete signs of slowing.

(Reporting By Joe Silha; Editing by Marguerita Choy)

Article source: http://www.reuters.com/article/2012/03/27/markets-nymex-natgas-idUSL2E8ERJO720120327

Warm weather a headache for Mich. asparagus farms

WALKERVILLE, Mich. (AP) — Asparagus is rising from the ground because of Michigan‘s extraordinarily warm weather, a condition that could eventually ruin the crop due to a lack of labor and inevitable frost.

Asparagus is a spring crop, especially in Oceana and Mason counties in the northwestern Lower Peninsula, but not this early. Though temperatures topped 80 degrees last week, lows in the next few days could drop to 32 or lower. A freeze watch was posted Sunday by the National Weather Service.

“I’ve never seen a spring like this — never,” Thomas Oomen of Oomen Farms told The Muskegon Chronicle (http://bit.ly/H6tL7e). “I’ve been in agriculture my whole life. It just creates a whole bunch of problems. If it freezes, the crop will just kind of go away. If the help isn’t here, we’ll have to mow the field off and start over. There is just another level of stress in this right now.”

Grower Mike Van Agtmael believes 50 of his 80 acres of asparagus could be at risk.

“Everyone is extremely nervous,” he said.

Migrant workers hand-pick virtually all of Michigan’s asparagus, going row by row while riding in a cart. But the workers are elsewhere in the United States at this time of year, and typically don’t make it to Michigan’s fruit-and-vegetable belt until late April or May.

“They have kids in school and a change in plans isn’t in the norm for them. That’s their life,” Oomen said.

Norm Myers, an educator with the Cooperative Extension Service, said a grower in Belding, northeast of Grand Rapids, already has 5 percent of his crop poking through the ground.

“The concern is that the earlier that it comes up the more likely it is going to frost,” Myers said. “That’s the ugly side of this warm weather.”

___

Information from: The Muskegon Chronicle, http://www.mlive.com/muskegon

Article source: http://news.yahoo.com/warm-weather-headache-mich-asparagus-farms-150321544.html

Link builds between weather extremes and warming


LONDON |
Sun Mar 25, 2012 2:03pm EDT

LONDON (Reuters) – Extreme weather events over the past decade have increased and were “very likely” caused by manmade global warming, a study in the journal Nature Climate Change said on Sunday.

Scientists at Germany’s Potsdam Institute for Climate Research used physics, statistical analysis and computer simulations to link extreme rainfall and heat waves to global warming. The link between warming and storms was less clear.

“It is very likely that several of the unprecedented extremes of the past decade would not have occurred without anthropogenic global warming,” said the study.

The past decade was probably the warmest globally for at least a millennium. Last year was the eleventh hottest on record, the World Meteorological Organization said on Friday.

Extreme weather events were devastating in their impacts and affected nearly all regions of the globe.

They included severe floods and record hot summers in Europe; a record number of tropical storms and hurricanes in the Atlantic in 2005; the hottest Russian summer since 1500 in 2010 and the worst flooding in Pakistan’s history.

Last year alone, the United States suffered 14 weather events which caused losses of over $1 billion each.

NOT NORMAL

The high amount of extremes is not normal, the study said.

Even between March 13 and 19 this year, historical heat records were exceeded in more than 1,000 places in North America.

For some types of extreme weather, there are physical reasons why they would increase in a warming climate. For example, if average temperature rises, then so will the number of heat records if all else remains equal, the study said.

Natural weather patterns like El Nino or La Nina can also cause highs in global temperature or increased precipitation which leads to floods.

“Single weather extremes are often related to regional processes, like a blocking high pressure system or natural phenomena like El Nino,” said Stefan Rahmstorf, co-author of the study and chair of the institute’s earth system analysis department.

“These are complex processes that we are investigating further. But now these processes unfold against the background of climatic warming. That can turn an extreme event into a record-breaking event.”

Recent years have seen an exceptionally large number of record-breaking and destructive heatwaves in many parts of the world and research suggests that many or even most of these would not have happened without global warming.

Currently, nearly twice as many record hot days as record cold days are being observed both in the United States and Australia, the length of summer heatwaves in western Europe has almost doubled and the frequency of hot days has almost tripled over the period from 1880 to 2005.

Extremely hot summers are now observed in about 10 percent of the global land area, compared with only about 0.1-0.2 percent for the period 1951 to 1980, the study said.

The link between storms and hurricanes and global warming is less conclusive but at least some of recent rainfall extremes can be attributed to human influences on the climate, it added.

(Reporting by Nina Chestney)

Article source: http://www.reuters.com/article/2012/03/25/us-weather-climate-change-idUSBRE82O0EA20120325