Key points of the intergovernmental climate change report

WARMING of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia.

The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, sea level has risen and the concentrations of greenhouse gases have increased. Human influence on the climate system is clear. Limiting climate change will require substantial and sustained reductions of greenhouse gas emissions.