Nicholas Stern
http://www.hm-treasury.gov.uk/media/999/76/CLOSED_SHORT_executive_summary.pdf


Climate change could have very serious impacts on growth and development.

If no action is taken to reduce emissions, the concentration of greenhouse gases in the atmosphere could reach double its pre-industrial level as early as 2035, virtually committing us to a global average temperature rise of over 2°C.

In the longer term, there would be more than a 50% chance that the temperature rise would exceed 5°C.
This rise would be very dangerous indeed; it is equivalent to the change in average temperatures from the last ice age to today.
Such a radical change in the physical geography of the world must lead to major changes in the human geography where people live and how they live their lives.

Adaptation to climate change – that is, taking steps to build resilience and minimize costs – is essential.

It is no longer possible to prevent the climate change that will take place over the next two to three decades, but it is still possible to protect our societies and economies from its impacts to some extent – for example, by providing better information, improved planning and more climate-resilient crops and infrastructure.
Adaptation will cost tens of billions of dollars a year in developing countries alone, and will put still further pressure on already scarce resources.
Adaptation efforts, particularly in developing countries, should be accelerated.


The costs of stabilizing the climate are significant but manageable; delay would be dangerous and much more costly.