Geoscience Reference
In-Depth Information
8
Compounding social and economic
impacts
The limits to adaptation
Ross Garnaut
Introduction
The climate within which human civilization and Australian society will
advance, stagnate or decline through the lives of our children and grandchildren
and beyond will be determined by how we think about and respond to the risks
of climate change
over the next decade.
A global average temperature rise of 4°C from pre-industrial levels (
1
4°C
GW or 3.5°C above 1990 levels) is well outside the relatively stable temperatures
of the last 12,000 years, which have provided the environmental context for the
development of human civilization. This Four Degree World would be unknown
territory for modern humans and probably for our species at any time in the past.
Even the best mitigation efforts will leave Australians dealing with difficult
climate change and they and other members of humanity will have no choice
but to try to adapt. But to what will they be adapting? And what will be their
chances of sustaining and building upon the fabulous legacy of 12,000 years of
human civilization and a quarter of a millennium of modern economic growth?
A false dichotomy is sometimes drawn between adaptation and mitigation, as
if these were alternative responses to climate change. Mitigation is the first and
most important element of an adaptation strategy. The cost of adaptation and
whether a planned adaptive response has any chance of working depend on the
effectiveness of mitigation and therefore the extent of climate change.
Adaptation is an inevitable accompaniment of mitigation. As earlier chapters
suggest, we are already feeling large impacts of climate change with warming of
less than 1°C since pre-industrial times. Some impacts are affecting Australia
directly. Examples include the disruption of old patterns of agriculture with less
rain in the growing season from April to October in southern Australia, and
increased frequency and intensity of extreme weather events (Garnaut, 2008:
106-12; Howden et al., 2013 [
Chapter 6
, this volume]). Warming of less than
1°C has already forced major changes in food and insurance markets; in what,
where and when we plant in Australian agriculture; in resources allocated to
management of natural disasters; and in the costs of utilities supplying water and
electricity.
