BUENOS AIRES, Argentina (Reuters) -- At least a third of the world's forests are in
danger from global warming, especially the cool boreal forests of North America, Europe
and Siberia, the World Wide Fund for Nature said Friday.
Warming weather could hurt trees' growth and reproduction more quickly than they could
be replaced by other tree species, according to a report presented by the WWF ahead of the
United Nations climate talks in Buenos Aires from Nov. 2-13.
Forest fires could break out more frequently. And attacks of pests, like an
unprecedented invasion of spruce budworms now gnawing into 50 million acres of Alaskan
The WWF is campaigning for developing countries to meet pledges in Kyoto, Japan, last
year to cut greenhouse gas emissions by about 5.2 percent. The world's largest polluter,
the United States, is among those most reluctant to clamp down on polluting industries and
The talks in Buenos Aires are meant to find ways to make sure the Kyoto targets are
met, but environmentalists fear government inaction will allow CO2 levels to continue to
``There is no continent in the world where the forests will not suffer from climate
change,'' said Stephan Singer, head of the WWF's climate and energy policy department.
Most at risk will be the dark ring of the evergreen ''boreal'' forests which cloak a
vast region of the cold north of North America, Scandinavia and Siberia. They could lose
40 percent of their area if greenhouse gases like carbon dioxide (CO2) push up world
temperatures as scientists fear.
``The impacts of climate change are expected to be largely detrimental, with many
models showing a dramatic shrinking of the extent of the boreal forest. The forests will
most likely be replaced at their southern edge by northern deciduous forests, or
agriculture, or in the drier areas by grassland or steppe vegetation,'' the WWF said.
Large areas of tropical forest could also be hit if rising temperatures increase the
likelihood of drought. Delicate mangroves -- tangled forests growing in tropical coastland
seas -- could be drowned by rapidly rising ocean levels.
Island forests could also vanish beneath swelling waves as higher temperatures cause
oceans to expand and melt icecaps. Sensitive woods near mountain tree levels could be
squeezed into smaller areas or vanish utterly.
``There are many threats to forests from human activities, from logging, from forest
fires, shifts in cultivation, from agriculture. So if climate change comes about it will
basically be the straw that breaks the camel's back,'' Singer said.
More than 50 percent of the world's natural forests have been destroyed over the past
100 years and an area equivalent to 57 soccer fields is ripped up each minute, he said.
Scientists have convinced world governments that increasing concentrations of
greenhouse gases like CO2 from burning fossil fuels are trapping ever more heat on Earth,
warming it up.
If trees -- which are 50 percent carbon -- are destroyed by global warming, then huge
quantities of CO2 could be released into the atmosphere and accelerate the process still
Many of the industrial world governments which pledged to cut CO2 emissions want
forests, which absorb the gas, to be computed as ``carbon sinks'' and discounted from
their Kyoto pollution reduction targets.
But environmentalists say this is just a way of avoiding cutting down on industry and
car use and that ``carbon sink'' calculations could be based on a sketchy scientific base.