The Impact on
Ecology
Nowhere is immune from the effects of global warming. Glaciers
are already
melting in places as far apart as Switzerland and
New Zealand, bringing in their wake avalanches, soil erosion,
and dramatic changes to river flows.
Snow is
receding
from the peaks of great mountain ranges
such as the Alps and the Andes, and as melting progresses, the
risk of serious flooding increases.
Away from the mountains, the oceans and seas are
warming, causing coral to die and putting many marine creatures
at risk. Warm water occupies more space than cold water, so as
the oceans gradually
heat
up, they also expand -
threatening to
overwhelm
many parts of the world, including the Mekong Delta,
as many as 300 Pacific islands, and wetlands as far afield as
Argentina and Bangladesh, Nigeria and the United States.
Scientists estimate that 70 per cent of the world's
sandy shorelines are already
eroding. Higher seas will take
their toll, causing failure of food supplies in some places: you
cannot grow wheat or root crops on
sodden
ground. All types of
land, from cornfields to
mangroves, will need to adjust to the
new climatic order.
The Impact on
Natural Habitats and Wildlife
We already know that unusual weather
conditions can cause many species to decline in numbers. The
danger now is that if those conditions were to become permanent
or extreme, numerous plants and animals would simply not recover
- and their
demise
would in turn lead to major shifts in the
balance of important ecosystems across the world.
Such extremes
include life-threatening
hurricanes, storms, and flooding on the
one hand, and severe droughts on the other. To take just one
example, natural recovery from hurricane disturbance is often
prolonged - some habitats take centuries before they are fully
functional again. |