(For a wrapup on Pakistan's floods, click)

By David Fogarty and Augustine Anthony

SINGAPORE/ISLAMABAD, Aug 10 (Reuters) - Floods that have
devastated Pakistan could be a sign of the future as climate
change brings greater extremes of weather to the region.

While climate scientists say single flooding events can't
be directly blamed on global warming, more intense droughts and
floods could be in the forecast for the future.

And for Pakistan's 160 million people, many already facing
regular droughts and floods, that could cost more lives and
threaten cotton, wheat and rice crops and infrastructure.

It could also add to the security challenges in what is
already one of the world's poorest and volatile nations that is
battling Islamic militancy. The government has been heavily
criticised over its poor response to the crisis.

Scientists say Pakistan could also suffer in the long-term
from declining amounts of meltwater from glaciers feeding the
Indus River, which is nation's life-blood.

For the current floods, rainfall of about 400 millimetres
(16 inches) in mountainous areas in the far north of Pakistan
and adjoining parts of Afghanistan between July 28 and 29
triggered a torrent of water down the Indus and Kabul Rivers.

"That was a record," said Qamar-uz-Zaman Chaudhry,
director-general of the Pakistan Meteorological Department.

"The only explanation can be the link to climate change.
Because that area very rarely receives monsoon rains," he told
Reuters, pointing to the risk of the monsoon belt shifting as
well as changes in the intensity of the monsoon.

LIMITS

He said the current floods could also be blamed to some
degree on deforestation and more people living in flood-prone
areas as the population keeps growing.

Pakistan has lost vast areas of forest over the past few
decades, while overgrazing often strips degraded land of
whatever plant cover is left. The government has set a target
to boost forest cover from 5.2 percent to 6 percent by 2014.

Climate scientists say it is much easier to link climate
change and heatwaves such as the one that has triggered
wildfires and wiped out wheat crops in Russia.

"Floods are harder to pin down," said leading Australian
climate scientist Neville Nicholls.

"We expect changes in precipitation but the science to
actually to attribute those to global warming hasn't been done
yet," Nicholls, of Monash University in Melbourne, said.

He also pointed to the global climate moving from an El
Nino to a La Nina, a natural swing in sea surface temperatures
in the Pacific Ocean that can trigger drought in Australia and
Southeast Asia and then floods, as well affecting South Asia
monsoon.

"In parts of the world, that sequence does lead to really
quite strange, anomalous rainfall," he said.

Indian experts point to evidence of rising temperatures in
the Himalayas and more intense rainfall events.

"No one can say for sure that this is all related to
climate change, but yes there is circumstantial evidence that
over (the last) 20 years very heavy rainfall events have
drastically increased," Bishwajit Mukhopadhyay, deputy
director-general of meteorology at the India Meteorological
Department, told Reuters.

Scientists say nations will need to start adapting to
climate change impacts such as more intensive droughts and
floods but poorer nations with limited cash face the toughest
challenge.

Pakistan, like any flood-prone country, needed early
warning systems, better storage of drinking water, even to move
people from vulnerable areas, said Andrew Ash, who leads a
climate adaption programme for Australia's state-funded
research body the CSIRO.

"There are definite limits to adaptation. We often talk
about adaptation as if we can adapt our way out of trouble," he
told Reuters. "But these sorts of events highlight that we
can't adapt our way out of all the impacts of climate change."

Pakistani food expert Abid Suleri, executive director of
the Sustainable Development Policy Institute, said the country
would need to work on seed varieties to adapt to climate
change.
(Additional reporting by Krittivas Mukherjee in New Delhi;
Editing by Robert Birsel and Miral Fahmy)