Geoscience Reference
In-Depth Information
latest assessment on impacts covered 976 information-rich pages. The
major chapters included studies of freshwater resources; ecosystems;
food, fi ber, and forest products; coastal systems and low-lying areas;
industry, settlements, and society; and human health. The report dis-
cusses potential problems in every region of the world, from tropical
Africa to the icy poles.
1
Clearly this topic cannot deal with every one of these topics, but a
few key questions can be addressed. Most people want to know what the
important impacts are and how large they are relative to other problems
facing humanity. How does global warming compare with the fi nancial
crisis, the long recession, and African poverty? And how will key natu-
ral systems fare in a warmer world?
The next chapters review some of the central concerns about cli-
mate change and also explore the diffi culties in making predictions.
Chapters 7 and 8 focus on two concerns that are central to human soci-
eties: agriculture and health. Each of these has been prominent in dis-
cussions about the potential impacts of climate change. They share a
common feature: Each will be affected by rapid technological and soci-
etal changes over coming decades. Moreover, given the growing impor-
tance of human decisions and technologies, climate is likely to play an
ever-smaller role over time in these sectors. The discussions will there-
fore emphasize the race between the forces of climate change and those
of human adaptation.
In Chapters 9 through 11, the focus shifts to areas that are less
manageable: rising sea levels, ocean acidifi cation, hurricane intensifi -
cation, and damage to wildlife and natural ecosystems. These are major
problems because it will be more diffi cult for human adaptations and
new technologies to slow or stop these.
I then pull the different strands together to summarize the overall
impacts of climate change.
MANAGED VERSUS UNMANAGED SYSTEMS
A central principle in understanding the impacts of climate change
is the difference between managed and unmanaged systems. The idea
