Meeting Minutes
Notes from Second LDAS meeting: Sept 2, 1pm, NCEP
LDAS Decisions and Discussion Summary:
NOTE: Please see the new LDAS Central Web Site at
http://ldas.gsfc.nasa.gov/ - many of the new LDAS datasets and
configuration issues will be detailed on this site. Please forward any
changes or new data sets for this site to Brian Cosgrove
(bac@ldas.gsfc.nasa.gov) or myself (Paul.Houser@gsfc.nasa.gov). This
site will eventually be moved to the NCEP server and be given an NCEP
address once some security/premission issues are resolved.
1) Decisions on Practical LDAS Issues
-Review of Previous LDAS decisions (Mitchell)
-2 people from each LDAS team will be granted accounts
on the new NCEP Origin 2000 server. This server will be used
for operational LDAS runs by each group. A testing directory
will also be allocated for wach group, however, experimental
LDAS and retrospective LDAS runs will generally not be done at
NCEP. Workstation ID forms were distributed and filled out - if you did
not fill one out and want access to NCEP's LDAS server, contact Ken
Mitchell or Curtis Marshall.
-Curtis Marshall distributed the proposed LDAS directory structure
on the NCEP server (we really need a name for this server). This is on
the LDAS Specs page - please review it and send any changes to Curtis.
-We discussed the retrospective LDAS runs witl no conclusion. This is a
big issue that we must define better. Most of this work will probably be
done by the Princeton/Washington Group. We have modern Precip and
Radiation forcing back to Mid 1996. Before this time, a different LDAS
forcing data set will need to be developed.
-The following issues were all deferred to the next LDAS meeting. I
suggest that we circulate a proposed list of common model outputs before
this meeting to come to some agreement soon.
1.1 Commonality of Model Configuration
1.1.1 Common Parameters, Mask, Forcing - can we agree? - do we NEED to agree?
1.1.2 Common Output
1.1.2.1 Experience from PILPS (Mitchell)
1.1.2.2 Experience from GSWP (Koster?)
1.2 Grid Definition
1.2.1 Grid Def. and Reasoning (Marshall)
1.2.2 Mask definition (Houser)
-We decided to redefine the LDAS domain. The new domain is defined on the
LDAS Specs page. The domain is from 25 to 53 lat and -67 to -125 lon.
This new grid includes all of the GCIP and Columbia river basins. We will
model all land points in this domain. The new mask is on the LDAS
parameters page (use the IBGP mask definition). We will have to work
through observational problems outside the U.S.
1.3.2 Elevation (Schaake?)
-The office of Hydrology will provide max, min, and average elevation and
perhaps slope on the LDAS 1/8 degree grid.
1.3.3 Soils (Schaake?)
-The office of Hydrology will provide a variety of soils information on
the LDAS grid. Priority in decreasing order are 1) Elevation, 2) Soil
Type, Soil Characteristics (%sand/silt/clay, texture), Conductivity.
2) Invited Presentations:
3:00pm 2.1) Dan Tarpley: Observed Radiation Issues
-Dan gave us a great presentation on the Observed Radiation Issues and
Characteristics. He showed us the current model biases and the complex
effects of shadowing. He also suggested several new directions they plan
to take to support LDAS (i.e. a multi-GOES alogrithm, etc.).
3:30pm 2.2) Huug Vandendool: Monthly Soil Moisture Modeling
-Huug also presented a very encouraging topic os understanding how soil
moisture (and land surface processes in general) is linked to
large-scale climatic anomalies. He has some very valuable analysis
techniques that will be exciting to apply in the LDAS context.
This site was constructed and is maintained by Brian A. Cosgrove: Brian.Cosgrove@gsfc.nasa.gov