Two Questions To Skeptical Science Regarding i) The Relation of Global Warming To Climate Change and ii) The Predictive Skill Of Multi-Decadal Global Climate Models

UPDATE November 12 2011: So far Skeptical Science has not responded to my questions. 

I posted a summary list of titles of the weblog posts over the last few weeks between Climate Science and Skeptical Science, and my conclusion from those interactions  in the weblog post

Response To Skeptical Science On A Series Of Weblog Posts

As part on a contining effort to reach out in this post, I request their answer to the following two questions:

1. Is global warming (and cooling) a subset of climate change or does it dominate climate change?

As documented in

National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. Committee on Radiative Forcing Effects on Climate Change, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., 208 pp,

climate change is much more than what is occurring from the radiative addition of CO2 and a few other greenhouse cases. The Skeptical Science viewpoint on this question would be informative.

In the Executive Summary of the NRC (2005), it is written

“Despite all these advantages, the traditional global mean TOA radiative forcing concept has some important limitations, which have come increasingly to light over the past decade. The concept is inadequate for some forcing agents, such as absorbing aerosols and land-use changes, that may have regional climate impacts much greater than would be predicted from TOA radiative forcing. Also, it diagnoses only one measure of climate change—global mean surface temperature response—while offering little information on regional climate change or precipitation. These limitations can be addressed by expanding the radiative forcing concept and through the introduction of additional forcing metrics. In particular, the concept needs to be extended to account for (1) the vertical structure of radiative forcing, (2) regional variability in radiative forcing, and (3) nonradiative forcing. “

The hypothesis is that neither the multi-decadal global-annual average surface temperature trend nor the global-annual average surface temperature offer little information on changes in the regional climate.

2.  What evidence exists that the multi-decadal global climate models can skillfully predict i) the real-world observed behaviour of large-scale atmospheric-ocean circulation features such as ENSO, the NAO, the PDO, ect. and ii) CHANGES in the statistics (patterning and in time) of these circulation features?

As I reported in the post

Insightful Interview In EOS Of Dr. De-Zheng Sun “Climate Dynamics: Why Does Climate Vary?”

De- Zheng Sun

“….the state-of- the- art three- dimensional models still do not properly simulate natural variability such as MJO and ENSO. As a result, models are not yet able to capture the anthropogenic effect that takes place in the form of climate variability. In other words, our models may be underestimating the effect from anthropogenic forcing on natural variability.It is time to look seriously at an alternative hypothesis, which is that the defining feature of global warming will be changes in the magnitude of climate variability…”

The hypothesis is that multi-decadal global climate model predictions (projections) , even when statistically or dynamically downscaled to regional and local spatial scales in a hindcast mode, provide no skillful predictions of regional and local climate change.

I look forward to the SkS  response on their weblog and what evidence they have to refute these hypotheses.

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