Global Warming
Takes Toll on Africa's Coral Reefs
SOUTH AFRICA: October
19, 2005
JOHANNESBURG -
Global warming is taking a toll on coral reefs off east Africa,
which will likely be killed off in a few decades if sea surface
temperatures continue to rise, a leading researcher warned on
Tuesday.
"Dangerous
climate change has already happened for coral reefs," Dr
David Obura told a conference on climate change science in
Johannesburg.
Kenyan-based Obura, a
researcher with CORDIO (Coral Reef Degradation in the Indian
Ocean), said there had been "catastrophic mortality"
among shallow-water coral reefs off East Africa following a
1997-98 El Nino event that pushed up sea surface temperatures in
the Indian Ocean.
"There was a 70
to 75 percent mortality during the El Nino in 1997-98 in shallow
water reefs off East Africa," he said.
Models suggested that
the events of 1998 could be repeated on a regular basis in 20 to
50 years' time because of rising sea surface temperatures.
Such a scenario would
have grim consequences for the region's rich corals, which are
crucial to East Africa's tourist industry, as they are a magnet
for scuba diving enthusiasts.
"They (corals)
can survive a bleaching. It is akin to a fever in mammals,"
Obura said. But if the stress was too great on the corals, then
they died off.
Coral bleaching refers
to the whitening of corals from a loss of pigment.
This is a signal of
ecosystem stress which can be triggered by sedimentation,
pollution, or rising temperatures, among other factors still being
disentangled by scientists.
Scientists maintain
global temperatures are rising rapidly because fossil fuel
emissions from cars, industry and other sources are trapping the
Earth's heat.
The Intergovernmental
Panel on Climate Change, a group of 2,000 scientists which advises
the United Nations, projects a further rise of 1.4-5.8 degrees
centigrade by 2100. Even the lowest forecast would be the biggest
century-long rise in 10,000 years.
REUTERS NEWS SERVICE