Judy Curry has a very important weblog post titled
Part of her text reads [highlight added]
The mitigation focus is on global climate and the century time scale, whereas the adaptation focus is regional and on timescales from the seasonal to decadal.
The mitigation focus and the century time scale has sapped the community of much resources in terms of manpower and computer time. I have talked with people in leading positions at several modeling groups, and the effort that is put into the simulations for the IPCC saps 50-70% of the total manpower time and resources of the modeling center.
What if we had devoted all of those resources to making better probabilistic predictions on timescales of 2 weeks to 3-4 months? Farmers would be able to make better choices about what crops to plant. Water resource managers could make better choices. Energy generation and demand could be made more efficient. Etc. Most of the developing world doesn’t have weather forecasts beyond two days, and often these forecasts do not anticipate extreme weather events (think Pakistan floods, Severe Cyclone Nargis). Anticipating extreme weather events by a week or two, or even a few days, could make an enormous difference in the developing world.
Judy is right when she writes “the simulations for the IPCC saps 50-70% of the total manpower time and resources of the modeling center”. In my view, the use of these resources to generate multi-decadal regional and global climate projections is scientifically unsound and a waste of money and peoples’ time.
Their goal is to provide a set of multi-decadal global climate model projections for use by the impact communities and to seek to refine the previous IPCC predictions of the magnitude of global warming in response to the addition of CO2, and other human climate forcings.
The obvious first question to be asked is what will these new model runs provide anything that we do not already know?
Second, what evidence, using hindcast model runs, exists to show that these model projections have any skill at the spatial and temporal level needed by the impacts community?
The answer to the first question, is that we already know added CO2 is a first order climate forcing. Thus why the huge expenditure of money and people to continue to address the same question for which we already know the answer?
For the second question, I am supportive of assessing how far in the future that skillful climate predictions are possible; i.e. predictabiltiy – see;
but this is a distinctly different application from providing unvalidated multi-decadal climate predictions.
I discuss this failed approach in my posts
The Failure Of Dynamic Downscaling As Adding Value to Multi-Decadal Regional Climate Prediction
I endorse Judy’s recommendation that
What if we had devoted all of those resources to making better probabilistic predictions on timescales of 2 weeks to 3-4 months?….Anticipating extreme weather events by a week or two, or even a few days, could make an enormous difference in the developing world.
I also propose the adoption of the bottom-up, resource-based perspective in order to develop a much better understanding of the risks that are faced with respect water, food, energy, human health and ecosystem function. This is the approach we present in our article
Pielke Sr., R.A., R. Wilby, D. Niyogi, F. Hossain, K. Dairuku, J. Adegoke, G. Kallos, T. Seastedt, and K. Suding, 2011: Dealing with complexity and extreme events using a bottom-up, resource-based vulnerability perspective. AGU Monograph on Complexity and Extreme Events in Geosciences, in press.
This is a more robust method than the narrowly focused top-down IPCC approach, for which 50-70% of the total manpower time and resources of modeling centers, is being spent.
My recommendation is that, in the USA and elsewhere, independent assessments (and congressional investigations) be completed as to the value of these large expenditures. In my view, this money being wasted.
Climate Science: Roger Pielke Sr. 
