6.

6.1
6.2
6.3
6.4
6.5

6.1

Climate change is a unique, global, long-term problem, involving complex interactions.

6.2

There are many technological options for reducing greenhouse gas emissions, some at low or negative cost. Forests and agricultural lands provide significant but not necessarily permanent carbon sinks, which may allow time for other options.

6.3

There will be both costs and benefits to reducing greenhouse gases. Most studies project that in 2010, the Kyoto Protocol should cost developed countries a reduction in projected GDP of about 0.2% to 2% without emission trading and about half of that with emission trading.

6.4

Greenhouse gas reduction programs need to overcome many barriers. Governments have a wide array of instruments at their disposal. With coordinated actions and international regimes, efficiency and equity should improve.

6.5

Further research is required to strengthen future assessments and to reduce uncertainties.