1.      Warming of the climate system is unequivocal, as is now evident from observations of increases in global averaged air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level.
 
2.      Most of the observed increase in global averaged temperatures since 1950 is very likely due to the observed increase in greenhouse gas concentrations from human activity.
 
3.      Global warming and sea level rise will continue for centuries due to the time scales associated with the climate system, even if greenhouse gas concentrations were to be stabilized.
 
4.      These anticipated changes in regional and global climate could have severe adverse impacts on the environment and society.
 

For more information about the JSG program in Climate Systems Science click here.