   The index ranked the vulnerability of the world's countries,
and the 50 cities deemed the "most commercially important," to
the impacts of climate change, by evaluating their risk of
exposure to extreme climate events, the sensitivity of their
populations to that exposure and the adaptive capacity of
governments to respond to the challenge.     "The combined GDP
in these cities is forecast to almost triple from US$275 billion
to US$804 billion by 2025, representing the greatest combined
growth in any of the risk categories," said the report, released
Wednesday. The figures, it said, underlined the way in which
"cities with some of the biggest economic growth potential are
among those with the greatest vulnerability to climate change."
Greenpeace's chief scientist Doug Parr said the report
highlighted "just how urgent the need is for the international
community to tackle climate change." "Without a binding global
agreement the economic and social impact of global warming will
be devastating," he said.  "It