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• News

  25 Jan 06, 20:23

  2005 was warmest year on record: NASA
  
  WASHINGTON (Reuters) - Last year was the warmest recorded on Earth's surface, and it was unusually hot in the Arctic, U.S. space agency NASA said on Tuesday.
  
  All five of the hottest years since modern record-keeping began in the 1890s occurred within the last decade, according to analysis by NASA's Goddard Institute for Space Studies.
  
  In descending order, the years with the highest global average annual temperatures were 2005, 1998, 2002, 2003 and 2004, NASA said in a statement.
  
  "It's fair to say that it probably is the warmest since we have modern meteorological records," said Drew Shindell of the NASA institute in New York City.
  
  "Using indirect measurements that go back farther, I think it's even fair to say that it's the warmest in the last several thousand years."
  
  Some researchers had expected 1998 would be the hottest year on record, notably because a strong El Nino -- a warm-water pattern in the eastern Pacific -- boosted global temperatures.
  
  But Shindell said last year was slightly warmer than 1998, even without any extraordinary weather pattern. Temperatures in the Arctic were unusually warm in 2005, NASA said.
  
  "That very anomalously warm year (199 has become the norm," Shindell said in a telephone interview.
  
  "The rate of warming has been so rapid that this temperature that we only got when we had a real strong El Nino now has become something that we've gotten without any unusual worldwide weather disturbance."
  
  Over the past 30 years, Earth has warmed by 1.08 degrees F (0.6 degrees C), NASA said. Over the past 100 years, it has warmed by 1.44 degrees F (0.8 degrees C).
  
  Shindell, in line with the view held by most scientists, attributed the rise to emissions of greenhouse gases such as carbon dioxide, methane and ozone, with the burning of fossil fuels being the primary source.
  
  The 21st century could see global temperature increases of 6 to 10 degrees F (3 to 5 degrees C), Shindell said.
  
  "That will really bring us up to the warmest temperatures the world has experienced probably in the last million years," he said.
  
  To understand whether the Earth is cooling or warming, scientists use data from weather stations on land, satellite measurements of sea surface temperature since 1982, and data from ships for earlier years.
  
  More information and images are available online at: http://www.nasa.gov/vision/earth/environment/2005-warmest.html.
• News

  1 Feb 06, 23:43

  Monday, 30 January 2006, 11:00 GMT
  Stark warning over climate change
  By Richard Black
  Environment Correspondent, BBC News website
  
  Climate report conclusions
  
  Rising concentrations of greenhouse gases may have more serious impacts than previously believed, a major scientific report has said.
  
  The report, published by the UK government, says there is only a small chance of greenhouse gas emissions being kept below "dangerous" levels.
  
  It fears the Greenland ice sheet is likely to melt, leading sea levels to rise by 7m (23ft) over 1,000 years.
  
  The poorest countries will be most vulnerable to these effects, it adds.
  
  The report, Avoiding Dangerous Climate Change, collates evidence presented by scientists at a conference hosted by the UK Meteorological Office in February 2005.
  
  The conference set two principal objectives: to ask what level of greenhouse gases in the atmosphere is too much, and what the options are for avoiding such a level.
  
  "It's the irreversibility that I think brings it home to people"
  Margaret Beckett
  
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  Your questions answered
  
  In the report's foreword, UK Prime Minister Tony Blair writes that "it is now plain that the emission of greenhouse gases... is causing global warming at a rate that is unsustainable."
  
  Environment Secretary Margaret Beckett said the report's conclusions would be a shock to many people.
  
  "The thing that is perhaps not so familiar to members of the public... is this notion that we could come to a tipping point where change could be irreversible," she told BBC Radio 4's Today programme.
  
  "We're not talking about it happening over five minutes, of course, maybe over a thousand years, but it's the irreversibility that I think brings it home to people."
  
  Vulnerable ecosystems
  
  The report sets out the effects of various levels of temperature increase.
  
  The European Union (EU) has adopted a target of preventing a rise in global average temperature of more than two degrees Celsius.
  
  But that, according to the report, might be too high, with two degrees perhaps enough to trigger melting of the Greenland ice sheet.
  
  This would have a major impact on sea levels globally, though it would take up to 1,000 years to see the full predicted rise of 7m.
  
  Above two degrees, says the report, the risks increase "very substantially", with "potentially large numbers of extinctions" and "major increases in hunger and water shortage risks... particularly in developing countries".
  
  'Without delight'
  
  The report asked scientists to calculate which greenhouse gas concentrations in the atmosphere would be enough to cause these "dangerous" temperature increases.
  
  "No country is going to turn off a power station which is providing much-desired energy for its population to tackle this problem"
  Sir David King
  
  Currently, the atmosphere contains about 380 parts per million (ppm) of carbon dioxide, the principal greenhouse gas of concern, compared to levels before the industrial revolution of about 275ppm.
  
  To have a good chance of achieving the EU's two-degree target, levels should be stabilised at 450ppm or below, the report concludes.
  
  But, speaking on Today, the UK government's chief scientific adviser, Sir David King, said that was unlikely to happen.
  
  "We're going to be at 400 ppm in 10 years' time, I predict that without any delight in saying it," he said.
  
  "But no country is going to turn off a power station which is providing much-desired energy for its population to tackle this problem - we have to accept that.
  
  "To aim for 450 (ppm) would, I am afraid, seem unfeasible."
  
  But Myles Allen, a lecturer on atmospheric physics at Oxford University, said assessing a "safe level" of carbon dioxide in the atmosphere was "a bit like asking a doctor what's a safe number of cigarettes to smoke per day".
  
  "There isn't one, but at the same time people do smoke and live until they're 90," he told Today.
  
  On the other question asked at the 2005 conference - what are the options for avoiding dangerous concentrations of greenhouse gases in the atmosphere? - the report says that technological options to reduce emissions do exist.
  
  It concludes that the biggest obstacles to the take up of technologies such as renewable sources of energy and "clean coal" lie in vested interests, cultural barriers to change and simple lack of awareness.