Climate Model Bias 6: WGII
22 hours ago Andy May 43 Comments
By Andy May
The previous parts of this series investigated model bias in the CMIP6 models and in their interpretation in AR6 WGI. This part looks at model bias in AR6 WGII, Climate Change 2022: Impacts, Adaptation, and Vulnerability.[1] The IPCC WGII report uses the possible future climate projections from the WGI report to project the future impact of climate change on society. It uses socio-economic models to accomplish this. As we saw in the previous parts of this series, the WGI report is biased and ignores possible natural contributions to recent observed global warming from changes in the Sun, cloud cover, and the meridional transport of energy.
The WGI/CMIP6 models, rather arbitrarily, assign all warming since 1750 to human influences, particularly CO2 emissions.[2] WGII accepts this controversial conclusion. It uses projected CO2 emissions combined with the WGI/CMIP6 models to predict future temperature and projected knock-on effects to other climate components, like precipitation, to model the future impact on human civilization.
WGII states that:
“Human-induced climate change, including more frequent and intense extreme events, has caused widespread adverse impacts and related losses and damages to nature and people, beyond natural climate variability.”[3]
AR6 WGII, page 9
This is only true if we accept their assumption about the range of natural climate variability, but as we saw in the previous parts of this series, their assumptions about natural warming, especially the impact of solar variability, are very controversial. Further, whether climate change is natural or human-caused, someone, somewhere, is nearly always going to be adversely affected by a change in climate, while others will benefit from the same change. How widespread is “widespread?”
https://wattsupwiththat.com/2024/03/12/climate-model-bias-6-wgii/
