Despite lingering doubts among many, there is consensus among
nearly all scientists that global climate change is happening and
that it is mainly caused by humans. There is a mounting weight of
evidence. Accelerating changes are occurring in vital aspects of
weather, climates, and environments. Yet there is uncertainty about
the specific extent and type of change that will occur in specific
places. All of these factors, plus the possibility of monumentally
negative consequences, all argue for taking prudent action
now.
The 2007 report of the International Panel on Climate Change and
the Stern report argue that climate change is likely to have
profound and accelerating effects, including the following long
list:
- more extreme temperatures
- less predictability about weather extremes
- more floods and droughts
- expanding deserts and arid lands
- increasingly scarce and polluted water resources
- shrinking wetlands
- rising sea levels
- expanding coastal salinisation
- dropping groundwater tables, and
- reductions in agricultural productivity
