Mitigation: reducing emissions and stabilizing the climate

Curbing greenhouse gas emissions remains a long-term solution to combating global warming. Unmitigated climate change will, in the long-term, be likely to exceed the capacity of natural, managed and human systems to adapt. In the past thirty years, emissions of these gases increased by 70 percent and without additional action by governments, emissions of the six main greenhouse gases are projected to rise by 25-90 percent by 2030 compared to 2000.

Any comprehensive solution to climate change will stabilize concentrations of greenhouse gases in the atmosphere at a safe level, a goal defined as the central objective of the UN Framework Convention on Climate Change. But this will involve considerable costs. The estimates of global investment requirements for mitigation vary widely, depending, in part, on how stringent the stabilization target is. Most estimates fall in a range from $250 billion to $800 billion per year between now and 2040. Many estimates for developing countries fall roughly between $100 billion and $250 billion, though they range up to $675 billion.

The pace and cost of any response to climate change will depend on the cost, performance, and availability of technologies that can lower emissions in the future. Although other factors such as growth in wealth and population are also very important.