Scientists most closely associated with recommending climate policies to government officials are refocusing their recommendations. Armed with new data that show the current state of the climate is worse than that predicted by any model used in the 2007 IPCC Report, scientists are trying to let government officials know that stated goals to decrease emission levels won’t go far enough in the alloted timeframe.
For instance, CO Gov. Ritter’s Climate Action Plan calls for a 20% reduction in 2005 GHG emissions by 2020. President Obama has called for 2020 emissions to be reduced to 1990 levels. If officials are serious about not introducing the worst climate change effects currently estimated (sea level rise, temperature, precipitation patterns, drought, etc.), their emission reduction goals must become much more bold. By 2050, reductions from 1990 levels must be at least 80%.
Climate models used in the 2007 IPCC Report forecasted a range of temperature increases of 1-6 degrees Celsius. Severe or abrupt climate changes weren’t expected until the upper limit of that range was reached. The beginnings of those climate changes have already been seen, with temperature increases of only 0.7 degrees Celsius. To wait until 6 or even 2 degrees of warming then seems like a very bad idea. A whole set of tipping points might be reached well before the worst warming was seen. Plenty of warming resides today “in the pipeline”. Greenhouse gas concentrations today are enough to continue to warm the globe for at least another 100 years. In light of the continuing data showing climate change effects, emissions standards must be more aggressively set and pursued.