The Second Generation Model (SGM) is a computable general equilibrium
model utilized by the Office of Atmospheric Programs (OAP) to
analyze issues related to climate change. The model was developed
by Jae Edmonds, Hugh Pitcher, Ron Sands and others at the Joint
Global Change Research Institute (JGCRI) of Pacific Northwest
National Laboratory and the University of Maryland.
The OAP has requested that EPA's Science Advisory Board
(SAB) provide an advisory on the SGM. An "advisory" is
similar to a peer review, but is offered early in the development
process for works-in-progress rather than after a model is
finalized or a document published. The SAB has assembled
a panel (the SAB SGM Advisory Panel) to review the model.
On December 2, 2004 the panel met via teleconference to
begin the discussion of the model. The Panel's first
meeting took place on Friday February 4th, 2005. The next
two meetings will take place via teleconference only and
are scheduled for April 1st, 2005 and May 6, 2005, both
at 2PM-4PM EST. The call in number is (866) 299-3188
by Conference Code 2023439867.
For meeting agendas, minutes, membership of the Advisory
Panel and the Panel's draft advisory, please see the
SAB website: http://www.epa.gov/sab/panels/sgm_adv_panel.htm
Model Documentation and Background Information
You will need Adobe Acrobat Reader,
available as a free download, to view the written
transcripts on this page. See EPA's
PDF page to learn more about PDF, and for a link
to the free Acrobat Reader.
The documents below have been provided to the SAB SGM Advisory
Panel, and serve as the main basis for review.
The two documents below were provided to the SAB SGM Advisory
Panel as additional background material for their review of SGM. Neither
of these documents, nor the models or articles to which they refer,
are being officially reviewed by the Panel.
Revised SGM Documentation, October 2005
- The Second Generation Model: Model Description
and Theory, PNNL-15432 (PDF,
51 pp, 1566 KB)
- The Second Generation Model: Data, Parameters,
and Implementation, PNNL-15431 (PDF,
39 pp, 356 KB)
- The Second Generation Model: Future
Directions for Model Development, PNNL-15437 (PDF,
10 pp, 126 KB)
- The Second Generation Model: Comparison
of SGM and GTAP Approaches to Data Development (PDF,
14 pp, 91 KB)
As of January 25, 2005, requests for public copies of the Second
Generation Model (SGM) may be made through the website of the
Joint Global Change Research Institute (JGCRI). Users may access
the model at
This page contains
a legal notice whose terms users must agree to. Next, users will
be directed to an information release form that they must acknowledge
having read, and then to a contact information form. After this
(free) registration procedure, users will be sent an email from
JGCRI's Antoinette Brenkert containing a link to download the
model package, as well as a "SGM User Guide," and a
user ID and password for the download.
The download itself will be a "zipped" file containing
the SGM executable file, and various Microsoft Excel and Access
files for running and viewing the model. Full instructions are
described in the user guide for users to be able to run a reference
and two carbon management cases. A PDF file containing the model
code will be available by Jan 28, 2005.
The version accessible for download will contain the USA region
only (SGM USA). Because of various proprietary rights of JGCRI
collaborator institutions to other countries' data, and/or the
use of purchased data as part of the model calibration process
(which requires release by the supplying institution) the full
(13 region) version of the SGM is not yet publicly available.
We expect the full SGM to be available sometime in the first
quarter of 2005.
For More Information
To learn more about the SAB's activities, please visit
To learn more about climate change related activities at the
EPA, please visit
To learn more about JGCRI, please visit