10.

10.1
10.2
10.4

10.1

The earth's average surface temperature has increased by about 0.6 °C (1°F) during last century, and human activities are increasing the levels of greenhouse gases which tends to warm the planet.

10.2

How much and how fast temperatures will continue to rise remains uncertain, and the exact impacts of climate change over the 21st century, especially for local regions, remain largely unknown.

10.4

However, global warming poses real risks. Because the exact nature and amplitude of these risks remains uncertain, we have to use our best judgment – guided by the current state of science – to determine what the most appropriate response should be.