Friday, February 15, 2008

Huge study gives wake-up call on state of world's oceans

· Human activity damages more than 40% of seas
· First 'big picture' map worse than expected

This article appeared in the Guardian on Friday February 15 2008 on p14 of the UK news section. It was last updated at 00:25 on February 15 2008.
Ocean atlas showing human impacts

A global map of the overall impact that 17 different human activities are having on marine ecosystems. Insets show three of the most heavily impacted areas in the world, and one of the least impacted areas.

Fishing, climate change and pollution have left an indelible mark on virtually all of the world's oceans, according to a huge study that has mapped the total human impact on the seas for the first time. Scientists found that almost no areas have been left pristine and more than 40% of the world's oceans have been heavily affected.

"This project allows us to finally start to see the big picture of how humans are affecting the oceans," said Ben Halpern, assistant research scientist at the University of California, Santa Barbara, who led the research.

"Our results show that when these and other individual impacts are summed up the big picture looks much worse than I imagine most people expected. It was certainly a surprise to me."

Human impact is most severe in the North Sea, the South and East China Seas, the Caribbean, the Mediterranean, the Red Sea, the Gulf, the Bering Sea, along the eastern coast of North America and in much of the western Pacific.

The oceans at the poles are less affected but melting ice sheets will leave them vulnerable, researchers said.

The study found that almost half of the world's coral reefs have been heavily damaged. Other concerns rest with seagrass beds, mangrove forests, seamounts, rocky reefs and continental shelves. Soft-bottom ecosystems and open ocean fared best but even these were not pristine in most locations.

Previous studies of human impacts have focused on a single activity or on an isolated ecosystem, and rarely on a global scale.

Fiorenza Micheli, an associate professor of biology at Stanford University, said the maps should guide ocean management in future.

"By seeing where different activities occur and whether they occur in sensitive ecosystems we can design management strategies aimed at shifting activities away from the most sensitive areas."

To make the map scientists compiled global data on the impacts of 17 human activities including fishing, coastal development, fertiliser runoff and pollution from shipping traffic.

They divided the ocean into one-square-kilometre cells and worked out which human activities might have touched each particular cell. For each cell, the scientists allocated an impact score to look at the degree to which human activities affected 20 types of ecosystems.

Around 41% had medium high to very high impact scores. A small fraction, 0.5% but representing 2.2m square kilometres (850,000 square miles), were rated very highly affected.

Halpern said the results, which were published in the journal Science and presented yesterday to the American Association for the Advancement of Science annual meeting, still gave room for hope. "With targeted efforts to protect the chunks of the ocean that remain relatively pristine we have a good chance of preserving these areas in good condition."

Andrew Rosenberg, a professor of natural resources at the University of New Hampshire, who was not involved with the study, said: "Clearly we can no longer just focus on fishing or coastal wetland loss or pollution as if they are separate effects.

"These human impacts overlap in space and time, and in far too many cases the magnitude is frighteningly high."

He added: "The message for policy-makers seems clear to me: conservation action that cuts across the whole set of human impacts is needed now in many places around the globe."

Highlighting examples of action, the researchers said that, for example, fishing zones have been shown to help ecosystems survive better, and navigation routes across seas have been altered to protect sensitive ocean areas.

Although the research will be helpful, making conservation decisions will require more detailed research at the local level, said Micheli.

"Our results and approach, augmented with additional local information, can also inform management at a local and regional scale. Looking at the data globally, some information is lost."

Halpern said the map was a wake-up call. "Humans will always use the oceans for recreation, extraction of resources, and for commercial activity such as shipping. This is a good thing. Our goal, and really our necessity, is to do this in a sustainable way so that our oceans remain in a healthy state and continue to provide us with the resources we need and want."

Climate change soon could kill thousands in UK, says report

This article was first published on guardian.co.uk on Tuesday February 12 2008. It was last updated at 16:35 on February 12 2008.
Eggborough power station

Eggborough power station, near Selby. The report says climate change could lead to a heatwave in the south-east of England killing 3,000 people. Photograph: John Giles/PA

Climate change could lead to a heatwave in the south-east of England killing 3,000 people within the next decade, a Department of Health report said today.

It put the chances of a heatwave of that severity happening by 2017 at 25%.

Without preventative action, the report said that a nine-day heatwave, with temperatures averaging at least 27 degrees over 24 hours, would cause 3,000 immediate deaths, with another 3,350 people dying from heat-related conditions during the summer.

It predicted that there would be an increase in skin cancers due to increased exposure to sunlight and that, over the next half century, air pollution could lead to an extra 1,500 deaths and hospital admissions a year.

While malaria outbreaks were likely to remain rare, the report – Health Effects of Climate Change in the UK 2008 – said health authorities would need to be alert to the dangers posed by possible larger outbreaks of malaria in continental Europe.

The report, a follow-up to a study first published in 2002, said the latest modelling now suggested that temperatures would rise by between 2.5C and 3C over the next century. Periods of very cold weather would become less common, but heatwaves would become more common.

It pointed out that the heatwave in France in 2003, which contributed to more than 14,000 premature deaths, had been attributed by climatologists, in part, to the influence of human behaviour on the climate,

"The air pollution climate of the UK will continue to change," the report went on.

"Though concentrations of a number of important pollutants are likely to decline over the next half-century, the concentration of ozone is likely to increase. This will increase attributable deaths and hospital admissions.

"The increases are likely to be significant: with the least constraining assumptions … up to about 1,500 extra deaths and hospital admissions per annum might be expected."

The report also said that new studies had confirmed the effects of increased exposure to ultra-violet light. "Skin cancers are expected to increase."

On malaria, the report said there was a very slight chance that the disease could return to the south of England during the next 50 to 100 years. But outbreaks were likely to be rare and to involve a small number of people.

However, health authorities would have to be on the alert for the emergence of new, more deadly strains of mosquitoes in Europe and the possibility that they could arrive in wetland areas of Britain.

Warmer summers would also lead to an increase in food poisoning. The report predicted that there would be up to 14,000 more cases of food poisoning, including salmonella, a year – an increase of 14.5%.

Tick-borne diseases such as Lyme disease were also likely to become more common, but that was more likely to be due to changes in land use than climate change.

Professor Robert Maynard, chairman of the expert panel that wrote the report, said: "Climate change is likely to be one of the major challenges that humanity faces this century. It is important that we assess the possible health impact and take any actions that could minimise the consequences."

Sir William Stewart, chairman of the Health Protection Agency, which published the report jointly with the Department of Health, said: "Climate change is perhaps the most significant environmental problem which mankind will face in the coming century.

"Efforts to reduce the extent of climate change are of course important, but it is likely that we will have to deal with at least some impacts on health."

In a foreword to the report, health minister Dawn Primarolo said the national health service would have to adapt to deal with the problems posed by climate change.

Measures would include: ensuring that hospitals were equipped to deal with the effects of heat, gales, and floods; developing local plans for heatwaves, gales and flooding; disaster preparation; and advising people how to adapt to climate change

Snow shuts down roads in San Diego County

  • Story Highlights
  • 27-mile stretch of I-8 closed for 12 hours by snow; 500 motorists stranded
  • At least 30 people taken to temporary shelters; teams check for cars off roads
  • San Diego County authorities report about triple normal number of accidents

SAN DIEGO, California (AP) -- A surprise storm lashed San Diego County with rain and snow, stranding as many as 500 motorists on a mountain freeway and pouring mud down onto another roadway but causing no major damage or injuries.

The weather was expected to clear Friday.

A 27-mile stretch of Interstate 8, which runs through the mountains in the eastern county and is a main artery from California into Arizona, was reopened before dawn Friday following a 12-hour shutdown.

The California Highway Patrol began escorting cars through, although big-rig trucks still were not allowed. The freeway was closed shortly after 4 p.m. Thursday when blowing snow and ice made the roadway impassable.

"It was just a big dump of snow, real fast," accompanied by high winds, California Highway Patrol Officer Jim Bettencourt said.

Cars spun out and hundreds of motorists were stopped in their tracks.

"I've been here for a while and trying to get around, but there's no going around, so you just have to be patient," stranded motorist Patty Kresin told KNSD-TV in San Diego.

Search-and-rescue teams went car to car. At least 30 people were taken to temporary shelters at a fire station and a casino nearby, according to the California Department of Forestry and Fire Protection.

By early Friday, authorities were pretty sure they had found all the stranded motorists, but teams were still checking for cars that might have gone over the side of the road, Bettencourt said.

The abandoned cars hampered snow plows.

"Now we have a virtual parking lot of empty vehicles," Bettencourt said. "You've got big rigs that are jackknifed. So it's going to be a pretty daunting task."

The unexpectedly severe weather snarled other roadways. Authorities reported 179 crashes on county roads between midnight and 9 p.m. Thursday, compared to the usual figure of 50 to 75 crashes in a typical day.

Authorities also shut down an 8-mile stretch of road between Poway and Ramona because of mudslides. About 2 feet of mud and rocks slid onto the highway after heavy rain fell in an area burned by last fall's wildfires.

The stormy weather was caused by a low-pressure system that originated in the Gulf of Alaska and unexpectedly moved into Southern California.

Rain, hail and snow also fell in the desert near Palm Springs where temperatures had soared to 85 degrees just days ago.

Tuesday, February 12, 2008

True scale of C02 emissions from shipping revealed

Leaked UN report says pollution three times higher than previously thought

Graphic: Pollution on the world's major shipping routes

This article appeared in the Guardian on Wednesday February 13 2008 on p1 of the Top stories section. It was last updated at 04:02 on February 13 2008.
A large cargo ship sits at anchor in the calm waters of a safe harbour

A large cargo ship sits at anchor in the calm waters of a safe harbour. Photograph: Alamy

The true scale of climate change emissions from shipping is almost three times higher than previously believed, according to a leaked UN study seen by the Guardian.

It calculates that annual emissions from the world's merchant fleet have already reached 1.12bn tonnes of CO², or nearly 4.5% of all global emissions of the main greenhouse gas.

The report suggests that shipping emissions - which are not taken into account by European targets for cutting global warming - will become one of the largest single sources of manmade CO² after cars, housing, agriculture and industry. By comparison, the aviation industry, which has been under heavy pressure to clean up, is responsible for about 650m tonnes of CO² emissions a year, just over half that from shipping.

Until now, the UN's Intergovernmental Panel on Climate Change has estimated shipping emissions to be a maximum 400m tonnes, but the new draft report by a group of international scientists is a more sophisticated measure, using data collected from the oil and shipping industries for the International Maritime Organisation, the UN agency tasked with monitoring pollution from ships. It not only shows emissions are much worse than feared, but warns CO² emissions are set to rise by a further 30% by 2020.

Contacted about the contents of the report, Dr Rajendra Pachauri, chair of the IPCC, said: "This is a clear failure of the system. The shipping industry has so far escaped publicity. It has been left out of the climate change discussion. I hope [shipping emissions] will be included in the next UN agreement. It would be a cop-out if it was not. It tells me that we have been ineffective at tackling climate change so far."

The figure is highly embarrassing for the four governments, including Britain, that paid for the report. Governments and the EU have consistently played down the climate impact of shipping, saying it is less than 2% of global emissions and failing to include shipping emissions in their national estimates for CO² emissions.

Pressure is now expected to increase on shipowners to switch to better fuels and on the EU to include shipping in its emission trading scheme. Last month aviation was provisionally included following intense pressure - but shipping escaped.

Previous attempts by the industry to calculate levels of carbon emissions were largely based on the quantity of low grade fuel bought by shipowners. The latest UN figures are considered more accurate because they are based on the known engine size of the world's ships, as well as the time they spend at sea and the amount of low grade fuel sold to shipowners.

The UN report also reveals that other pollutants from shipping are rising even faster than CO² emissions. Sulphur and soot emissions, which give rise to lung cancers, acid rain and respiratory problems are expected to rise more than 30% over the next 12 years.

The health implications of shipping emissions are most acute for Britain and other countries bordering the English Channel, one of the world's busiest shipping lanes. A recent peer-reviewed study of shipping emissions found world shipping led directly to 60,000 deaths a year.

Peter Smith, managing director of Intertanko, the grouping of the world's largest tanker operators which provided data for the report, said the industry was taking steps to cut emissions. "World trade and ship numbers have seen a steady increase, but in parallel there have been economies of scale with larger, more efficient ships. Individual ships have steadily been reducing their fuel consumption for the last 20 years. One litre of fuel on a modern very large crude carrier moves one tonne of cargo more than 2,800km; this is more than twice as far as 20 years ago."

Caroline Lucas, Green MEP for South-east England, said: "These new figures highlight the shocking complacency of governments which have completely ignored shipping emissions. It is essential that our own government's new climate change bill includes both shipping and aviation emissions and measures are urgently brought forward at EU level."

A spokesman for the Department for Environment, Food and Rural Affairs said the government would support the development of a global emissions trading scheme through the IMO, and was also "investigating the feasibility of including maritime emissions" in the EU's trading scheme. He said the shipping industry must take its "share of responsibility" for tackling climate change.

Monday, February 11, 2008

Plague of rats as UK turns wetter

Even cars are at risk as floods and building sites drive out rodents from their underground lairs

This article appeared in the Observer on Sunday February 10 2008 on p24 of the News section. It was last updated at 00:27 on February 10 2008.

Driven out of sewers by summer floods and an urban building boom, then nurtured by warmer winters and the leftovers of fast food, rats have been moving into homes, gardens and even cars around the country.

Rat-catchers and companies selling poison and traps are reporting a boom in business, with urban housing estates among the worst affected areas. Long-term growth in rodent populations is also blamed on a decline in 'sewer-baiting', the practice of laying down poison twice a year to prevent rat numbers building up underground.

Because rats breed on average five times a year, with seven or eight in each litter, growth can be rapid. The recent surge in numbers has been linked to a boom in urban development - not least the preparations for the 2012 London Olympics - and last summer's floods, which drove rats out from underground, through holes and cracks in pipes and drains.

Rentokil, the UK's largest pest control company, said demand rose by more than a quarter last year as hits on its website trebled. Killgerm, the country's biggest seller of rat poison, said sales rose by a quarter in 2007.

Rentokil estimates there are 65 million to 80 million rats in Britain, eating their way through 210 tonnes of food a year. This compares with an estimated 45 million to 50 million a decade ago, a rise of nearly 40 per cent, though the company admits such calculations are 'not an exact science'. The biggest increases appear to have been in the south of England, western Scotland and Northern Ireland; only East Anglia and the south Midlands reported a fall. 'It's a bit like crime statistics: it's difficult to tell whether the number of incidents has gone up, or if the reporting is more prevalent,' said Rentokil's UK managing director, Jed Kenrick. 'But there's no doubt that the number of calls we're getting about rodents is significantly up on 12 months ago.' Rats can spread diseases to humans through their urine, including Weil's disease and salmonella, though the Health Protection Agency said cases which could be linked to rats were 'rare' and there was no evidence of any increase in recent years.

Reuben and Louisa Hunter of Palmer's Green, north London, returned from a family holiday in Northern Ireland last month with their 14-month-old baby Sophie, to find that a rat had gnawed its way through the plastic around their car's gear stick, seat belts and the baby seat. 'The car looked like it had been broken into,' Sophie's father said.

People for the Ethical Treatment of Animals (Peta) says that rather than call in the pest control experts it is more humane to avoid attracting rats in the first place by keeping food and buildings sealed. 'Rats are highly intelligent, social animals who excel at learning,' said Poorva Joshipura, director of Peta Europe. 'They do not want to die trying to gnaw their leg off in traps or slowly suffering from poison.'

Pest watch: How to keep rodents at bay...

· Place food and rubbish in sealed containers and clean under cookers, fridges and cupboards.

· Store pet food carefully and clean feeding bowls regularly.

· Seal holes into buildings - mice can get through the width of a ballpoint pen - and keep pipes and drains in good repair.

· Check under outside decking, a favourite nesting place for rats and mice.

Biofuel demand leading to human rights abuses, report claims

This article was first published on guardian.co.uk on Monday February 11 2008. It was last updated at 16:04 on February 11 2008.
Palm oil kernels

Palm kernels, harvested in countries such as Indonesia for the oil which is a rich source of biofuel. Photograph: Tengku Bahar/AFP/Getty

EU politicians should reject targets for expanding the use of biofuels because the demand for palm oil is leading to human rights abuses in Indonesia, a coalition of international environmental groups claimed today.

A new report, published by Friends of the Earth and indigenous rights groups LifeMosaic and Sawit Watch, said that increasing demands for palm oil for food and biofuels was causing millions of hectares of forests to be cleared for plantations and destroying the livelihoods of indigenous peoples.

The report, Losing Ground, said many of the 60-90 million people in Indonesia who depend on the forests are losing their land to the palm oil companies.

Pollution from pesticides, fertilisers and the pressing process is also leaving some villages without clean water.

"The unsustainable expansion of Indonesia's palm oil industry is leaving many indigenous communities without land, water or adequate livelihoods. Previously self-sufficient communities find themselves in debt or struggling to afford education and food. Traditional customs and culture are being damaged alongside Indonesia's forests and wildlife," the report reads.

It claims that oil palm companies often use violent tactics as they move in to convert the land to plantations.

"Human rights – including the right to water, to health, the right to work, cultural rights and the right to be protected from ill-treatment and arbitrary arrest – are being denied in some communities.

"If palm oil is to be produced sustainably, the damaging effects of unjust policies and practices in the Indonesian plantation sector must be addressed," the report said.

The alleged human rights abuses come after several recent reports have highlighted the environmental problems caused by the conversion of land for farming palm oil.

Last week a study by the University of Minnesota and Nature Conservancy, published in Science, found that the carbon lost through the clearance of forests, peat lands or even grasslands far outweighs the greenhouse gas savings that can come from biofuels.

Conversion of land for corn, sugarcane, palm oil or soybeans released 17 to 420 times more carbon than the annual savings from replacing fossil fuels with bioethanol or biodiesel, the researchers said.

Last month the Commons environmental audit committee called for a moratorium on targets for the use of biofuels until their impact could be better assessed.

The EU currently wants biofuels such as bioethanol and biodiesel to make up 10% of transport fuel by 2020. Britain has a separate target of 5% of biofuels in petrol and diesel by 2010.

In its energy directive last month, the commission proposed the introduction of sustainability criteria because of fears about the environmental impact of growing fuel crops.

But Friends of the Earth and LifeMosaic said the targets would drive a huge increase in palm oil in Indonesia, adding there were plans for a further 20m hectares of plantations by 2020 – an area the size of England, the Netherlands and Switzerland combined.

Friends of the Earth biofuels campaigner, Hannah Griffiths, said: "As well as being bad for the environment, biofuels from palm oil are a disaster for people.

"MEPs should listen to the evidence and use the forthcoming debate on this in the European parliament to reject the 10% target.

"Instead of introducing targets for more biofuels the EU should insist that all new cars are designed to be super-efficient.

"The UK government must also take a strong position against the 10% target in Europe and do its bit to reduce transport emissions by improving public transport and making it easier for people to walk and cycle," she added.

Biofuel farms make CO2 emissions worse


Land conversion increases greenhouse gases - study
· Carbon debt may take centuries to pay off

This article appeared in the Guardian on Friday February 08 2008 on p14 of the UK news and analysis section. It was last updated at 00:14 on February 08 2008.

Transforming ecosystems into farms for biofuel crops will increase global warming and result in net increases in carbon emissions, according to a study.

Scientists have found that converting rainforests, peatlands and grasslands can outweigh the carbon savings made from biofuels and produce "carbon debts" which could take centuries to pay off.

The study will add to concerns about the ability of biofuels to replace fossil fuels. The EU is reviewing its pledge that biofuels such as bioethanol and biodiesel should make up 10% of transport fuel by 2020. Britain has a separate target of 5% biofuels in petrol and diesel by 2010.

In the study, US researchers calculated that converting natural ecosystems to grow corn or sugarcane to produce ethanol, or palms or soybeans for biodiesel, could release between 17 and 420 times more carbon than the annual savings from replacing fossil fuels.

This is due to the carbon contained in the original plants and soils which is released as CO2 when the vegetation rots after it is cleared. The researchers said this carbon debt must be paid before biofuels produced on the land could count towards reducing greenhouse gas emissions.

"This research examines the conversion of land for biofuels and asks the question 'Is it worth it?'" said Joe Fargione, a scientist for the environmental group The Nature Conservancy. "Does the carbon you lose by converting forests, grasslands and peatlands outweigh the carbon you 'save' by using biofuels instead of fossil fuels? And surprisingly, the answer is no."

In Indonesia the researchers found that converting land for palm oil production ran up the worst carbon debts, requiring 423 years to pay off. Producing soybeans in the Amazon would take 319 years of soy biodiesel to offset the carbon debt.

Stephen Polasky of the University of Minnesota, one of the authors of the study, published today in the journal Science, said: "We don't have proper incentives in place because landowners are rewarded for producing palm oil and other products but not rewarded for carbon management. This creates incentives for excessive land clearing and can result in large increases in carbon emissions."

Fargione said all biofuels now in use destroyed habitats. "Producing food-based biofuel will require that still more land be converted to agriculture," he said. The team also identified biofuels which did not contribute to global warming, including agricultural waste and grasses grown on land not suitable for crops.

"Biofuels made on perennial crops grown on degraded land that is no longer useful for growing food crops may actually help us fight global warming," said Jason Hill of the University of Minnesota, who also took part in the study. "One example is ethanol made from diverse mixtures of native prairie plants."

Global meltdown: scientists isolate areas most at risk of climate change

· Experts assess point at which it is too late to act
· Disastrous repercussions of warming are spelled out

This article appeared in the Guardian on Tuesday February 05 2008 on p1 of the Top stories section. It was last updated at 15:40 on February 06 2008.
Ice boulders left behind after a flood caused by the overflowing of a lake in Greenland

Ice boulders left behind after a flood caused by the overflowing of a lake in Greenland. Photograph: Uriel Sinai/Getty images

Scientists have long agreed that climate change could have a profound impact on the planet; from melting ice sheets and withering rainforests, to flash floods and droughts.

Now a team of climate experts has ranked the most fragile and vulnerable regions on the planet, and warned they are in danger of sudden and catastrophic collapse before the end of the century.

In a comprehensive study published today, the scientists identify the nine areas that are in gravest danger of passing critical thresholds or "tipping points", beyond which they will not recover.

Although the scientists cannot be sure precisely when each region will reach the point of no return, their assessment warns it may already be too late to save Arctic sea ice and the Greenland ice sheet, which they regard as the most immediately in peril. By some estimates, there will not be any sea ice in the summer months within 25 years.

The next most vulnerable area is the Amazon rainforest, where reduced rainfall threatens to claim large areas of trees that will not re-establish themselves. The scientists also expressed concerns over the Boreal forests in the north, and have predicted that El Niño, the climate system which has a profound impact on weather from Africa to North America, will become more intense. The scientists are so concerned they have called for an early warning system to monitor each of these fragile ecosystems.

The international team, whose study appears in the Proceedings of the National Academy of Sciences, represents some of the world's most prestigious organisations, including the Potsdam Institute for Climate Impact Research in Germany, the University of East Anglia and Oxford University's Environmental Change Institute. The scientists polled 52 environmental experts and combined their responses with discussions among 36 leading climate researchers at a workshop at the British embassy in Berlin. Each was asked to rank regions at greatest risk of climate change in the next century.

"There's a perception that global warming is something that will happen smoothly into the future, but some of these ecosystems go into an abrupt decline when warming reaches a certain threshold," said Tim Lenton, an environmental scientist at the University of East Anglia and lead author of the study.

"If we know when the different tipping points are, we can use them to inform targets to limit global warming. It gives us something to aim for," he added.

Last year, the UN's expert panel of climate scientists warned average temperatures could increase by as much as 6.4C by the end of the century, with a rise of 4C most likely. Such a rise would bring food and water shortages to vulnerable parts of the world, displace millions of people and wipe out hundreds of species.

In the latest study, the scientists calculate Arctic sea ice will go into irreversible decline once temperatures rise between 0.5C to 2C above those at the beginning of the century, a threshold that may already have been crossed. There is already a 50% chance that the Greenland ice sheet will soon begin melting unstoppably, although it could take hundreds of years to melt completely. The meltwater would raise global sea levels by seven metres.

A temperature rise of 3C could see more intense El Niños, with profound effects on the weather from Africa to North America.

Warming of 3C to 5C could reduce rainfall in the Amazon by 30%, lengthening the dry season. The Boreal forests could also pass their tipping point, with large swaths dying off over the next 50 years. In Africa, more rainfall may regreen the Sahel region, but the west African monsoon could collapse, leading to twice as many unusually dry years by the end of the century. The Indian summer monsoon is predicted to become erratic and in the worst case scenario, begin to flip chaotically, unleashing flash floods one year and droughts the next.

Measurements of the western Antarctic ice sheet show the balance of snowfall and melting has shifted and it is now shrinking. According to the study, a local warming of more than 5C could trigger uncontrollable melting, adding five metres to sea levels within 300 years. Under the same warming, Atlantic currents that power the Gulf Stream could be severely disrupted.

"If you can get some warning that you're nearing one of these thresholds, you can get to work on adapting to it. You could work harder on reducing emissions, or you might use it as impetus to try other options," said Lenton.

Explainer: What could happen next

If greenhouse gas emissions continue unchecked, the global average temperature will reach 2C above pre-industrial levels by 2050, according to the government's 2006 Stern report on climate change.

One of the first impacts will be droughts and floods, as rainfall increases at high latitudes and drops in the tropics. Some glaciers will disappear, though crop yields in some countries could rise, scientists believe.

Last year, a report from the Intergovernmental Panel on Climate Change, concluded that human activity was "very likely" to be behind most of the warming seen in recent decades. It predicted a rise of between 2.4C and 6.4C by 2100.

The most likely rise, of 4C by the end of the century, would cause droughts across Africa, and a fall in harvests of 15% to 35%. Globally, crop yields would fall 10%.

Sea levels would rise by up to 59cm, with Bangladesh and Vietnam among the worst hit, along with coastal cities such as New York, London, Tokyo, Kolkata and Karachi. In Britain alone, there would be 1.8 million people at risk of flooding. The western Antarctic and Greenland ice sheets would begin to melt irreversibly and Europe would lose 80% of its Alpine glaciers. Across the Arctic, half of the tundra is at risk.

A 4C rise is predicted to drive 20% to 50% of land species to extinction and put 80m more Africans at risk of malaria as mosquitoes thrive.

Climate warming threatens Antarctic king penguins

From: Reuters

/wildlife/article/30979

WASHINGTON (Reuters) - King penguins that feed on fish and squid at the northern edges of Antarctica are threatened by global warming, which is cutting down on their food supply, researchers reported on Monday.

King penguins, the second-largest species after emperor penguins, are at the top of the food chain in their sub-Antarctic environment, thriving on small fish and squid rather than the tiny krill and other crustaceans that sea mammals favor.

This makes king penguins good indicators of changes in their ecosystem, scientists said in research published in the Proceedings of the National Academy of Sciences.

Scientists at the CNRS Institut Pluridisciplinaire Hubert Curien in Strasbourg, France, studied king penguins on Possession Island in the southern Indian Ocean over nine years.

The researchers found that high sea surface temperatures in the area where the king penguins spent the winters cut the amount of available marine prey, which in turn cut the survival rate of adult king penguins.

Their study found a 9 percent decline in the adult penguin population for every 0.46 degree F (0.26 degree C) of sea surface warming.

This means these penguins could be at high risk under current global warming scenarios, which predict an average increase of 0.36 degree F (0.2 degree C) per decade for the next 20 years.

(Editing by Sandra Maler)

Video

"Manufactured Landscapes" SEE THIS BRILLIANT MOVIE! You'll never have the same shopping experience again.