Loading ...
Sorry, an error occurred while loading the content.

Repost: Earth ‘losing fight against global warming’

Expand Messages
  • Pat Neuman
    http://groups.yahoo.com/group/ClimateArchive/message/2073 ... carbon ... years to ... the sinks for ... carbon ... increasing ... Berkeley, ... by ... bloom
    Message 1 of 2 , Dec 30, 2005
    • 0 Attachment
      http://groups.yahoo.com/group/ClimateArchive/message/2073

      --- In ClimateArchive@yahoogroups.com, mtneuman@j... wrote:
      >
      >
      > Earth `losing fight against global warming'
      >
      > > 07 August 2005
      > By Jenifer Johnston
      >
      > http://www.sundayherald.com/51146
      >
      >
      > THE Earth is losing its natural resistance to global warming as the
      > oceans and forests reach capacity in their ability to soak up
      carbon
      > emissions, say scientists.
      > Using a new computer model, researchers "fast- forwarded" 100
      years to
      > reveal that unless emissions are curbed, land and seas –
      the "sinks" for
      > carbon dioxide – will become steadily less effective at removing
      carbon
      > from the atmosphere, causing the planet to heat faster and
      increasing
      > temperatures and droughts.
      >
      > Lead researcher Dr Inez Fung of the University of California,
      Berkeley,
      > told the Sunday Herald the model debunks one argument put forward
      by
      > global-warming sceptics that plants will flourish and the oceans
      bloom in
      > a warmer environment.
      >
      > "Our work shows that if we keep going on our current course of
      fossil
      > fuel emissions, the land and oceans will not be able to slow the
      rise of
      > carbon dioxide in the atmosphere the way they are doing now. Land
      and
      > oceans absorb about half of the carbon dioxide produced by human
      activity
      > at the moment. If we accelerate our emissions, the saturation rate
      will
      > increase," she said.
      >
      > Fung's model suggests that as heat and droughts increase, plants
      cut back
      > their intake of carbon dioxide to save water. Ultimately, they stop
      > absorbing it at all. Similarly, as the oceans heat up they
      struggle to
      > absorb carbon dioxide which then collects near the surface, further
      > preventing absorption and accelerating global warming.
      >
      > Using data from 1982 onwards, Fung said the northern hemisphere has
      > "greened" each spring and summer as the climate has warmed,
      leading to
      > more atmospheric CO2 being absorbed by plants.
      >
      > However, since 1994, as droughts have made the world hotter and
      drier,
      > plants have been unable to cope. Even though plants could take in
      more
      > CO2 in spring, that has been offset by decreasing CO2 uptake during
      > summers which have become increasingly dry, literally "browning"
      the
      > Earth.
      >
      > "We're saying `hold on a second – plants may not be happier in a
      warmer
      > and drier world'. This negative effect of hot, dry summers
      completely
      > wiped out the benefits of warm, wet springs. If you look at
      satellite
      > pictures of the Earth over this time you can actually see this
      happening
      > now," Fung said.
      >
      > Fung's planet model predicts that by 2050 – as the biosphere
      struggles to
      > absorb CO2 being pumped into the atmosphere by humans burning
      fossil
      > fuels faster and faster – the planet will not be able to keep up,
      and
      > that, at a low estimate, global temperatures will rise 1.4°C .
      >
      > "The Earth has a natural rate of absorption that you just cannot
      > accelerate – you can't make the land accept more CO2 just because
      more is
      > being released," she said. "If the rate of fossil fuel emissions
      is too
      > high, the carbon storage capacity of the land and oceans decreases
      and
      > climate warming accelerates."
      >
      > Last week the World Wildlife Federation warned that Scotland's
      average
      > temperature for 2005 is 1°C above average. Overall, Scotland's
      average
      > annual temperature has increased by 1°C in the past four decades.
      >
      > Friends of the Earth Scotland's Dr Dan Barlow warned: "It is not
      > surprising that the Earth's ability to deal with rising carbon
      emissions
      > has limits and it is increasingly clear that we have a very narrow
      window
      > in which to act to avert climate chaos."
      >
      > Dr David Reay of the Institute of Atmospheric and Environmental
      Science
      > at the University of Edinburgh said the study's predictions
      are "clearly
      > important".
      >
      > "As scientists we're aware that you cannot keep pumping CO2 into
      the
      > atmosphere and expect the Earth to keep absorbing it. This study
      is very
      > important in terms of giving us a window on the future," he said.
      >
      > Fung, one of the world's leading climate scientists, has spent
      decades
      > studying the carbon cycle of the planet, producing a sophisticated
      model
      > which takes into account the tiniest of details, such as the
      salinity of
      > oceans and forest floor litter decomposition rates and the effects
      of
      > temperature, rainfall, clouds and wind speed on these kinds of
      > interactions.
      >
      > She told the Sunday Herald: "The Earth is entering a climate space
      we've
      > never seen before … we don't know where the threshold is. You
      might think
      > that a one or two degree increase is not all that much but if
      we're on
      > the threshold, it could make a big difference."
      >
      > 07 August 2005
      >
    Your message has been successfully submitted and would be delivered to recipients shortly.