Environmental Engineering Reference
In-Depth Information
gas emissions. The obvious conclusion is that the increasing economic pro-
duction from the natural systems of Australia is at an environmental cost.
Tim Flannery made this point about the unsustainable use of Australia's
natural resources in
The Future Eaters
, arguing that we are consuming the
opportunities of future generations by our lifestyle choices (1994).
Global studies draw the same conclusion. UNEP has now produced three
reports in its
Global Environmental Outlook
series. They show some suc-
cesses, such as the concerted international effort to stop releasing the chem-
icals that deplete the ozone layer and 'encouraging reductions in many
countries' of urban air pollution. They also document 'environmental chal-
lenges' - increasing emissions of greenhouse gases, over-exploitation of
water, 1200 million people without clean drinking water and twice that
number without sanitation, increasing numbers of species being lost, fisher-
ies in decline, land degradation, and problems caused by increasing release
of nitrogen into natural systems.
A new report by the International Geosphere-Biosphere Programme,
Global Change and the Earth System: A Planet Under Pressure,
paints a dis-
turbing picture. It says human activities are affecting global systems 'in com-
plex, interactive and apparently accelerating ways', so that we now have the
capacity to alter natural systems in ways 'that threaten the very processes and
components … on which the human species depends'. The most urgent
issue is climate change. The politicians of the developed world accepted the
scientific arguments when they negotiated the Kyoto agreement to slow
down release of greenhouse gases. Only the Bush regime in Washington and
the Howard Government in Canberra have refused to ratify this treaty.
The Earth as a whole has warmed about 0.6 degrees Centigrade in the
last hundred years, with Australia warming slightly more than the global
average. The Earth is now warmer than at any time since credible records
began. As predicted by climate scientists, there have been other changes
associated with the warming: shrinking of glaciers, thinning of polar ice,
rising sea levels, changing rainfall patterns and more frequent extreme
events like droughts and severe storms. While we only have solid informa-
tion about the southern hemisphere for two hundred years, the record for
the northern hemisphere suggests it is now warmer than at any time in the
last two thousand years.
The world body of scientific expertise, the Inter-governmental Panel on
Climate Change (IPCC), has refined its mathematical models of climate and
compared the models with records. They now take into account the different
