by Judith Curry, July 15, 2017 in ClimateEtc.
In understanding climate change risk, and deciding on the ‘if’ and ‘what’ of ‘action’, we need to acknowledge that we don’t know how the climate of the 21st century will play out (Deep Uncertainty, folks). Four possibilities:
It is possible that human-caused climate change will be swamped by much larger natural climate variability.
It is possible/plausible that the sensitivity of the climate is on the low end of the IPCC envelope (1.0-1.5C), with a slow creep of warming superimposed on much larger natural variability.
It is possible/plausible that the IPCC projections are actually correct (right for the wrong reasons; too much wrong with the climate models for much credibility, IMO).
It is possible that AGW and natural variability could conspire to cause catastrophic outcomes
by Larry Kummer, July 15, 2017 in WUWT
After 30 years of failure to gain support of the US public for massive public policy measures to fight climate change, climate activists now double down on the tactics that have failed them for so long. This post explains why it will not work. Nor should it. Instead they should trust the IPCC and science, showing both the good and bad news.
by Willis Eschenbach, July 13, 2017 in WUWT
Over at Dr. Curry’s excellent website, she’s discussing the Red and Blue Team approach. If I ran the zoo and could re-examine the climate question, I’d want to look at what I see as the central misunderstanding in the current theory of climate.
This is the mistaken idea that changes in global temperature are a linear function of changes in the top-of-atmosphere (TOA) radiation balance (usually called “forcing”).
by Nic Lewis, July 8, 2017 in Climate Audit
A new paper in Science Advances by Cristian Proistosescu and Peter Huybers “Slow climate mode reconciles historical and model-based estimates of climate sensitivity” (hereafter PH17) claims that accounting for the decline in feedback strength over time that occurs in most CMIP5 coupled global climate models (GCMs), brings observationally-based climate sensitivity estimates from historical records into line with model-derived estimates. It is not the first paper to attempt to do so, but it makes a rather bold claim and, partly because Science Advances seeks press coverage for its articles, has been attracting considerable attention.
by Red Istvan, July 6, 2017 in WUWT
See also here
by Sergey Kravtsov, June 15, 2017
The observed internal variability so estimated exhibits a pronounced multidecadal mode with a distinctive spatiotemporal signature, which is altogether absent in model simulations. This single mode explains a major fraction of model-data differences over the entire climate index network considered; it may reflect either biases in the models’ forced response or models’ lack of requisite internal dynamics, or a combination of both.
by Pierre Gosselin, June 15, 2017 inClimateChangeDispatch
Global Warming More Moderate Than Worst-Case Models
A new study based on 1,000 years of temperature records suggests global warming is not progressing as fast as it would under the most severe emissions scenarios outlined by the Intergovernmental Panel on Climate Change (IPCC).
by Pierre Gosselin, 2017 in NoTricksZone
94 climate-gates total
28 new gates
145 links to reports with details
by Kenneth Richard, June 8, 2017 in NoTricksZone
The conventional basic climate model applies “basic physics” to climate, estimating sensitivity to CO2. However, it has two serious architectural errors. It only allows feedbacks in response to surface warming, so it omits the driver-specific feedbacks
by Jennifer Marohasy, June3, 2017
Important new book coming out …
Contributors to Climate Change: The Facts 2017 do not conform to a unitary view. As I explain in the book’s introduction:
“An advantage of my approach in the compiling of the chapters for this book – an approach where there has been no real attempt to put everything into neat boxes – is that there are many surprises. I am referring to the snippets of apparently anomalous information scattered through the chapters. These can, hopefully, one day, be reconciled. As this occurs, we may begin to see the emergence of a coherent theory of climate – where output from computer-simulation models bears some resemblance to real-world measurements that have not first been ‘homogenised’.
by Kenneth Richard, May 29, 2017
by Yves Goddéris et al., April 10, 2017, Nature Geoscience
The onset of the late Palaeozoic ice age about 340 million years ago has been attributed to a decrease in atmospheric CO2 concentrations associated with expansion of land plants, as plants both enhance silicate rock weathering—which consumes CO2—and increase the storage of organic carbon on land. However, plant expansion and carbon uptake substantially predate glaciation
by P. Gosselin, April 8, 2017
Looking at data objectively, it is pretty clear that there is little relationship between weather/climate and the rising CO2 concentrations in the atmosphere, as the global warming pause between 1997-2016 shows –
by Hourdin et al., March 2017,
Bulletin of the American Meteorological Society
We also discuss the challenges and opportunities in applying so-called objective methods in climate model tuning. We discuss how tuning methodologies may affect fundamental results of climate models, such as climate sensitivity. The article concludes with a series of recommendations to make the process of climate model tuning more transparent.
by Judith Curry, Feb 2017
Professor Judith A. Curry is the author of over 180 scienti c papers on weather and climate and is a recipient of the Henry G. Houghton Research Award from the Amer- ican Meteorological Society in 1992. She recently retired from the Georgia Institute of Technology, where she held the positions of Professor and Chair of the School of Earth and Atmospheric Sciences. She is currently President of Climate Forecast Appli- cations Network.