Models, Methods, Software

Here and here.

I sent a slightly revised copy of the comment on the Proposed CO2 Ruling, given in this post, to Ms. Lisa jackson, Administrator of EPA. The letter to Ms. jackson is shown below. I received a reply from Rona Birnbaum, Chief, Climate Science & Impacts Branch, Climate Change Division. (The actual signing of the letter was a task delegated to someone whose name I can’t read.)

As in all previous cases in which I have attempted to convey the critical necessity of Independent Verification and Validation to persons outside the software development community, I failed again. It is obvious that Ms. jackson, Rona Birnbaum, or whoever read and responded to the letter, have no idea what I’m talking about.

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John A is the site admin (CTO) and Webmaster for this blog, and all of auditblogs.com. After several requests by me he has added his Tip Jar over there to the left.

Please consider dropping a few coins to help with covering his costs and time.

Thanks.

My contribution to the comments regarding the Proposed Findings by the EPA regarding CO2 are given in this post. I will send hard copy of the letter to the EPA.

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I have a day job, so activity here has considerably slowed, even beyond the usual slowness. I was constructing a gridded, multi-layered, transient, radiative-convective, energy-balance model when the opportunity to kind of repair some of the recent financial damages came along.

On a very positive note, I am optimistic that additional wanderlust fulfilling Moto Road Trips are in the future if the damages are sufficiently repaired. This time next year I hope to be on the road for another no destinations, no reservations road trip on the small lines on real time road trip planners.

I have started working on a toy model and plan to include analytical sensitivity analysis as part of the methods.  These notes, and an associated extended discussion that I have up-loaded, serve as a short introduction to the subject.

The file is here:

Summary

These notes introduce a few of the ideas and concepts associated with sensitivity analysis for algebraic and ordinary differential equations. By sensitivity I mean what are the effects of changes in the numerical values of the parameters in a system of equations relative to a response function of interest. The response function can take any mathematical form, but I will focus on the values of the dependent variables of the equation system.

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The focus on this previous post was the fact that approximations made at the continuous-equation level mean that the model’s mass and energy budgets are different from the mass and energy budgets of the physical system. Note that there are very significant additional issues associated with the discrete approximations applied to the continuous equations and the numerical solutions of these. These issues in the discrete domain, in my opinion, have the potential to far outweigh issues in the continuous domain. Accurate integration of the discrete approximations over the enormous times scales of interest is a very tough problem.

The present post looks at some more issues associated with energy conservation in the discrete domain.

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it is not even viscous dissipation. There is also an energy imbalance in the NASA/GISS ModelE code due to the error in the ‘viscous dissipation’. The energy imbalance is about the same magnitude as the imbalance associated with increased concentrations of CO2 in the atmosphere.

Updated January 14, 2009, down near the end.

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This post is a continuation of discussions of the modeling of viscous dissipation in GCMs. The issue has recently come up again over at Lucia’s Blog in this thread. The thread at Lucia’s is related to the posts on this Blog here, here, and here. I have also in the past commented on the issue at Climate Audit, Professor Pielke Sr.’s Climate Science, and Real Climate. The dissipation questions come up now and then in several Blogs.

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While pursing the NASA/GISS ModelE coding as part of getting back to the dissipation questions that have come up on Lucia’s Blog in this thread, I ran across yet even more interesting coding. The thread at Lucia’s is related to the posts on this Blog here, here, and here. The dissipation questions come up now and then in several Blogs.

But first, a short diversion.
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