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The
impact of warming on inhabitants of the region, adapted as they are to ice and
snow, is likely to be highly destructive
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As
Europeans bask in what is one of the warmest winters on record, it’s almost
possible to believe in the beneficence of climate change – even if in the
Czech Republic and neighbouring Slovakia, it is rousing brown bears out of their
hibernation early.1 But basking in the glow
of global warming is misguided for two fundamental reasons. The first is that it
views the effects of rising temperatures from a temperate part of the world,
which has room to absorb rises and falls in temperature, rather than from areas
with more extreme – and hence more vulnerable – weather systems. Second, it
is absurdly short-termist. The warmer winters of today’s Europe are just the
beginning of a centuries’ long process, one that virtually every scientist on
record warns will have the same effect on the planetary global system as it is
having on Europe’s brown bears. Shaken out of its own natural cycles, the
weather is set to become inexorably hotter, more unpredictable and more
destructive as the century progresses.
Africa
and the Arctic Under Threat
The
dramatic effects of climate change are most clearly evident in areas of the
world with more extreme weather conditions. Two regions present graphic
illustrations of this: the Arctic and sub-Saharan Africa. The Arctic and
southern Africa are, literally, poles apart, yet the effects of global warming
in both regions are already evident, and are set to worsen considerably in the
second half of the twenty first century, with potentially far reaching effects,
both within these areas and for the rest of the world.
The
recent Arctic Climate Impact Assessment (ACIA) report, released in November
2004, reveals just how far the Arctic is under threat.2
The ACIA report was compiled for the Arctic Council by an international team of
300 researchers, and summarizes four years of research in the region. The Arctic
Council is comprised of the eight nations with Arctic territories: the US,
Canada, Denmark, Finland, Iceland, Norway, Russia and Sweden, and the report
represents the most comprehensive survey of climate change in the region to
date. Its findings make for disturbing reading.
The
report confirms that global warming in the Arctic has already had an impact:
over the past 50 years, average winter temperatures in Alaska, western Canada,
and eastern Russia have risen as much as 4oC. Over the next century,
temperatures are projected to rise by up to 7oC. The report confirms that the
northern ice cap is warming at twice the rate of the rest of the world. This is
because warming at the northern pole is enhanced by ‘positive feedback’.
Where landmass is covered by snow and ice, 80% to 90% of solar radiation is
reflected back into space. But when these white surfaces disappear, more solar
radiation is absorbed by the underlying land or sea as heat. This heat, in turn,
melts more snow and ice. At the same time, the air in the Arctic is much drier
than air at lower latitudes, so less energy is used up in evaporating water,
leaving more as heat.3
Researchers
used models developed by the Intergovernmental Panel on Climate Change (ICC) to
plot possible effects of such rapid warming, and found the effects are likely to
be extensive. According to the average of the five models used, the Arctic will
lose 50 percent to 60 percent of its ice distribution by 2100. One model
predicts that by 2070, the Artic will be so warm it will no longer have any ice
in the summer.4
Rising
Temperatures
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Brown
bears are coming out of their hibernation early
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The
impact of this warming on the traditional inhabitants of the region, adapted as
they are to ice and snow, is likely to be highly destructive. The retreat of sea
ice, the report says, "is very likely to have devastating consequences for
polar bears, ice-living seals, and local people for whom these animals are a
primary food source."5 Moreover, increases in glacial melt and river runoff add more water to the
oceans, raising sea levels and possibly slowing the currents that bring heat
from the tropics to the poles.
Calculations
by scientists at the Hadley Centre indicate that rapid Arctic warming of less
than 3oC could start a runaway melting of the Greenland ice sheet that will
eventually raise sea levels worldwide by seven meters.6 The report also highlights potentially devastating problems associated
with the release of methane and carbon dioxide as permafrost thaws and tundra
decomposes. Methane is a highly potent greenhouse gas, and there is enough
methane locked up in the Siberian tundra to raise global temperatures to
unsustainable levels.7
If
the Arctic is a vast – and vulnerable – ecological region, so too is Africa.
Yet, Africa is susceptible to the inexorable march of climate change, not
because it is so cold, but because it is so hot. Moreover, many African
countries are the poorest in the world; hence their capacity to marshal
resources to monitor and mitigate the effects of climate change is minimal. As a
result, agricultural production and biodiversity are likely to suffer major
consequences as the effects of global warming gather pace on the continent.
The
temperature across Africa has risen by approximately 0.7oC over the twentieth
century. Yet the rate of this increase is set to rise rapidly; climate change
scenarios for Africa indicate future warming across the continent ranging from
0.2°C (0.36°F) per decade to more than 0.5°C (0.9°F) per decade.8
Sea levels are also projected to rise by 15 to 95 centimeters (6 to 37 inches)
by 2100. Although Africa is typified by a series of microclimates, with the
particular effects of climate change variable and unpredictable, general trends
indicate less rainfall, greater aridity, increased desertification and greater
vulnerability to drought.
The
impacts of these changes will be felt most powerfully in the agricultural
sector. Agriculture in low latitude developing countries is especially
vulnerable to climate change for two reasons. The first is because the climates
of many of these countries are already too hot, so increased warming will have
an adverse effect on crop productivity. The second is because agriculture and
agro-ecological systems are the most important economic sectors in most African
countries, providing the livelihood of up to 70 percent of the population.9
Moreover, much agriculture is not capital and
technology intensive, which means there is little capacity to adapt to climatic
changes when they do occur. As a result, food security, already highly
vulnerable across large parts of the continent, will become even more insecure
as temperatures rise.
Biodiversity
May Suffer
The
human population of Africa is not the only one vulnerable to temperature
increases. Africa contains around one fifth of the world’s plant, animal and
bird species. Many animals are under threat as their traditional habitats are
likely to become eroded under the impact of climate change. Concentrations of
plant biodiversity, such as the Cape Floral Kingdom, are also threatened by
changes in rainfall, and both plants and animals will need migratory
‘corridors’ to allow them to escape should localised habitats become too
degraded.
Unfortunately,
not nearly enough research has been undertaken on the impact of climate change
for the human, animal or plant populations of Africa. At the same time, capacity
to manage and extend conservation schemes, or to utilize alternative
technologies capable of mitigating or harnessing climatic changes, remain
underdeveloped. The impact of global warming will therefore have further
effects, as massive exploitation of landscapes is likely to occur as conditions
across the continent deteriorate.
A
Bleak Future
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The
future depends on how quickly we are able to curb further increases in carbon
dioxide emissions
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The
amount of carbon dioxide now in the atmosphere as a result of a century or more
of industrialization means that global warming will continue through the twenty
first century, even if all CO2
emissions ceased overnight. But the future for the world’s most precious and
vulnerable habitats critically depends on how far, and how quickly, we are able
to curb further increases in CO2 emissions.
If
we continue to consume fossil fuels at our current rate, the future for the
people, the animals, and indeed for the planet itself looks bleak. If we act
decisively, the ecological fabric of the planet will have a chance to adapt and
survive.
As
African ecologist, Paul Desanker says, “Substantial
reductions of heat-trapping gas emissions in developed countries and adaptation
strategies are crucial… The conservation of African biodiversity will ensure
delivery of ecosystem goods and services necessary to human life support systems
(soil health, water, air, etc…). An integrated approach to environmental
management is needed to ensure sustainable benefits for Africa.”10
Exactly the same is true of the Arctic, and indeed of the
whole world. Life on earth itself may depend on whether we have wisdom to
understand and respond effectively to this challenge.
Kate
Prendergast is a British freelance researcher and journalist with a
particular interest in African politics and development. Your emails will be
forwarded to her by contacting the editor at: ScienceTech@islam-online.net.
[1]
Snow, Where'd You Go? The Associated Press, 13 January 2005:
http://www.truthout.org/docs_05/011405X.shtml
[2]
Arctic Climate Impact Assessment (ACIA): http://amap.no/acia/
[3]
Arctic warming at twice global rate, New
Scientist, 02 November 2004
[4]
Ibid
[5]
Impacts of a Warming Arctic, ACIA, 2004: 16
[6]
F Pearce, Doomsday Scenario, New Scientist, 22 November 2003
[7]
Ibid
[8]
P Desanker, 2002, The Impact of Climate Change on Life in Africa, World Wildlife
Fund
[9]
Climate Change and Agriculture in Africa:
http://www.ceepa.co.za/Climate_Change/
[10]
P Desanker, 2002, The Impact of Climate
Change on Life in Africa, World Wildlife Fund
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