Models, Methods, Software

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.

Read the rest of this entry »

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.

Read the rest of this entry »

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.
Read the rest of this entry »

In a previous post I gave an illustration of how GISS/NASA employees have implemented new and innovative ways to produce inactive code using the capabilities provided by F90/95. I had run across the following statements in routine DIAG.f:

EWATER(J)=EWATER(J)+EL !+W*(SHV*T(I,J,L)*PK(L,I,J)+GRAV
! * *HSCALE*LOG(P(I,J)/PMID(L,I,J)))

The ‘!’ in the first line is going to be very difficult to remember it exists and correctly maintain. Someone might come along and say, “I wonder what that’s doing in the middle of an executable statement.” and promptly un-do the comment. Or un-do the comment of the second line while overlooking the comment in the first line. That would make a screw up on several levels.

Today I have found many more examples of innovative coding by employees of GISS/NASA. It is clear that the NASA Software Quality Assurance procedures are ignored by GISS/NASA. It is equally clear that there are no Software Quality Assurance procedures being applied to the GISS/NASA ModelE code. None.

Update November 2, 2008 down near the end.

Read the rest of this entry »

Well, GISS/NASA employee Dr. Gavin Schmidt has done it again. He has given direct proof that the fundamental concepts of software Verification and Validation and other Software Quality Assurance procedures are not in the work universe of GISS/NASA.

Read the rest of this entry »

Using the NASA/GISS ModelE code browser I ran across the MODULE CONSTANT in which several constants are setup as parameters.

Read the rest of this entry »

Here’s an example of what a lack on coding guidelines (or ignoring them) can lead to. From the NASA/GISS ModelE online source code browser:

SUBROUTINE SURFCE 1,30
!@sum SURFCE calculates the surface fluxes which include
!@+ sensible heat, evaporation, thermal radiation, and momentum
!@+ drag. It also calculates instantaneous surface temperature,
!@+ surface specific humidity, and surface wind components.
!@auth Nobody will claim responsibilty

This is the entire header information for a 1228-line routine.

The last line says it all.

The several Global Climate Model or General Circulation Model (GCM) codes around the world are the work horses for the ‘what-if’ studies relative to the Global Average Temperature (and many, many other things) that appear in the IPCC Assessment Reports. There are about 20 of these codes, more or less. The actual models in the codes vary considerably from code-to-code and as a function of time with a given code. The GISS ModelE code is the NASA versions of GCMs.

Some GISS/NASA information about the ModelE GCM code is available here. There you will find information about the documentation of the model and code along with access to download the source and and an online HTML-based code viewer.

Read the rest of this entry »