Arctic Sea Ice Extent Higher Than 2005 According to DMI
Arctic Sea Ice Extent Higher Than 2005 According to DMI
Arctic Sea Ice Extent Higher Than 2005 According to DMI
The red line is 2005. The thick black line is 2013.…
New Paper: Climate Models Cannot Explain Global Warming Stagnation Over Past 15 Years: ’15 years, from 1998 -2012, is no longer consistent with model projections even at the 2% confidence level’
New Paper: Climate Models Cannot Explain Global Warming Stagnation Over Past 15 Years
http://www.thegwpf.org/paper-climate-models-explain-global-warming-stagnation-15-years/
A new paper by prominent German climatologists Dr. Hans von Storch and Dr. Eduardo Zorita, et al, finds “that the continued [global] warming stagnation over fifteen years, from 1998 -2012, is no longer consistent with model projections even at the 2% confidence level.”
In other words, there is a greater than 98% probability that climate models are unable to explain the stagnation in warming over the past 15+ years.
The authors suggest 3 possible explanations for this:
1. the models underestimate natural climate variability
2. the climate models fail to include important forcings such as ocean oscillations and solar amplification
3. the models assume exaggerated climate sensitivity to man-made CO2
The authors point out that even if climate sensitivity to CO2 was greatly reduced future models, it is still “hardly feasible” that the models would reproduce the 15 year stagnation of temperature, stating, “a recalibration [with lower CO2 sensitivity] reproducing the reduced warming of the last 15 years appears hardly feasible.” All of which suggests that CO2 is not the control knob of climate and natural variability is.
Can climate models explain the recent stagnation in global warming?
Hans von Storch (1) , Armineh Barkhordarian (1) , Klaus Hasselmann (2) and Eduardo Zorita (1)
(1) Institute for Coastal Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
(2) Max-Planck-Institute for Meteorology, Hamburg, Germany
In recent years, the increase in near-surface global annual mean temperatures has emerged as considerably smaller than many had expected. We investigate whether this can be explained by contemporary climate change scenarios. In contrast to earlier analyses for a ten-year period that indicated consistency between models and observations at the 5% confidence level, we find that the continued warming stagnation over fifteen years, from 1998 -2012, is no longer consistent with model projections even at the 2% confidence level. Of the possible causes of the inconsistency, the underestimation of internal natural climate variability on decadal time scales is a plausible candidate, but the influence of unaccounted external forcing factors or an overestimation of the model sensitivity to elevated greenhouse gas concentrations cannot be ruled out. The first cause would have little impact of the expectations of longer term anthropogenic climate change, but the second and particularly the third would.
Estimates of the observed global warming for the recent 15-year period 1998-2012 vary between 0.00370C/year NCDC)(1), 0.00410C/year (HadCRUT4)(2) …