- International climate experts now believe
that measures to reduce industrial pollution will have an unintended side-effect
- they will also help to speed up global warming.
- The experts, members of the Intergovernmental
Panel on Climate Change (IPCC), say the world's temperature will rise over
the next century much faster than they had been expecting.
- They had thought it would be about two
degrees higher by 2100 than it is now.
- But a new draft estimate says the increase
is likely to be nearly half as much again - 2.8 degrees.
- The IPCC, an internationally respected
group of climatologists, is expected to issue a final report next April.
But the draft has been published by the Kyodo news service in Japan.
- A no-win choice
- The reason for this startling upwards
revision is bizarre - cutting pollution will actually turn up the heat.
- The key to understanding the IPCC forecast
is a peculiar property of sulphuric acid particles.
- These are emitted in the form of sulphuric
oxide from the combustion of fossil fuels, especially from industry.
- When the particles are dispersed in the
atmosphere they act as a sort of insulator, and help to limit the amount
of solar energy reaching the earth.
- This in turn helps to slow down the pace
of global temperature increase.
- The IPCC's previous estimates of global
warming a century from now had assumed a growth in future emissions of
- But it now says that pollution control
technology will achieve a steep drop in sulphuric oxide emissions from
factories between 2020 and 2050.
- Scenarios agree
- The draft report follows usual IPCC practice
in spelling out several probable scenarios, rather than saying that one
is certain to happen.
- But all the scenarios agree that a drastic
drop in the quantity of sulphuric particles is likely.
- They have also been designed to take
account of factors such as projected population increase and economic growth.
- The report will face policy-makers with
a cruel dilemma, bevause there are compelling reasons for trying to reduce
sulphuric oxide pollution as quickly as possible.
- The particles damage air quality, which
threatens human health.
- And they are responsible for acid rain,
which destroys stonework and has turned some Scandinavian lakes into lifeless
- Showers falling in Japan have been found
to be as acid as vinegar, reputedly capable of discolouring clothing.
- The IPCC report will also hasten the
trend away from high sulphur fuels, like much coal and some sorts of oil,
towards natural gas.