The U.S. Environmental Protection Agency (EPA) recently issued a new set of proposed regulations aimed at reducing carbon dioxide emissions from existing U. S. power plants. The premise for this EPA action is that unless CO2 emissions are reduce global temperatures would rise by the end of this century to levels that would cause catastrophic climate change damage. But the basis for such action is not science but rather politics. In our previous posting, it was shown that climate models that predict global temperature are not skilled and have not predicted actual measured global temperatures. Using these models to base legislation is playing Russian Roulette with the US economy.
Knappenberger and Michaels (K&M) posted on 12 June in WUWT “EPA leaves out the most vital number in their fact sheet”. They show that this initiative will not have any measureable effect on global temperatures. K&M summarize the “regulation”:
“The EPA’s regulations seek to limit carbon dioxide emissions from electricity production in the year 2030 to a level 30 percent below what they were in 2005. It is worth noting that power plant CO2 emissions already dropped by about 15% from 2005 to2012, largely, because of market forces which favor less-CO2-emitting natural gas over coal as the fuel of choice for producing electricity.”
“For some reason, they left off their Fact Sheet how much climate change would be averted by the plan. Seems like a strange omission since, after all, without the threat of climate change, there would be no one thinking about the forced abridgement of our primary source of power production in the first place, and the Administration’s new emissions restriction scheme wouldn’t even be a gleam in this or any other president’s eye.”
“But no worries. What the EPA left out, we’ll fill in.
“Using a simple, publically-available, climate model emulator called MAGICC that was in part developed through support of the EPA, we ran the numbers as to how much future temperature rise would be averted by a complete adoption and adherence to the EPA’s new carbon dioxide restrictions*.”
The answer? Less than two one-hundredths of a degree Celsius by the year 2100. 0.018°C to be exact.
Well how did they come up with that number?
- They used the Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC)— to examine the climate impact of proposed regulations.They used the three IPCC Representative Concentration Pathways (RCP). RCP4.5=low-end emissions, RCP6.0=middle of the road and RCP8.5=high emissions.
- They estimated the US power plant CO2 emissions.
Figure 1. Carbon dioxide emissions pathways defined in, or derived from, the original set of Representative Concentration pathways (RCPs), for the global total carbon dioxide emissions as well as for the carbon dioxide emissions attributable to U.S. electricity production.
“We then used MAGICC to calculate the rise in global temperature projected to occur between now and the year 2100 when with the original RCPs as well as with the RCPs modified to reflect the EPA proposed regulations (we used the MAGICC default value for the earth’s equilibrium climate sensitivity (3.0°C)).”
Figure 2. Global average surface temperature anomalies, 2000-2100, as projected by MAGICC run with the original RCPs as well as with the set of RCPs modified to reflect the EPA 30% emissions reductions from U.S power plants.
Because the difference between lines is so small, the authors added two tables for the data illustrated in figure 2.
Yes, this posting says that the computer models are not suitable to make policy decisions and yet the K & M posting is predicated on a computer model. Two things here. First, in the course of making this new policy the EPA climate model must have been run by the EPA. They did not list a drop in global temperatures so they know it is devastating. Second, the EPA is not likely to claim the K & M work is invalid because EPA must use this model in their other pronouncements about climate .
The K& M posting should be read in its entirety.