LDAS Meeting Minutes - Wednesday, December 6, 2000
Place: SSMC2, Room 8246, NWS/OHD, 1325
East-West Highway, Silver Spring, MD 20910
Next LDAS
meeting: January 22nd, 2001 at NCEP
Meet OHD
Director Gary Carter
Discuss the
status of action items from the last meeting:
-
OH/NASA - A new
land/sea mask for precipitation forcing was created by Brian and Yun. Brian
will create a weighting map to estimate precipitation for regions outside the
US. Brian will also send the new mask to Dag and Justin.
-
NASA- Brian
will re-process a forcing dat from June 99 and on, with updated Wayne Higgins
daily gage precipitation and Rachel Pinkers radiation data.Brian will
play with a few different algorithms for precipitation estimation.
-
Princeton -
snow documentation?
-
NCEP -
-
Dag has
e-mailed GRIB code numbers to each group and sent vegetation class map to
Christa
-
Dag posted the
validation maps on the internet and will make available the (i,j) coordinates
for all validation basins
-
OHD/NCEP -
-
OHD will make
hourly MAP data between 1960-1998 available in a few (2?) months.
-
Sacramento
model coding was finished and Dag generated a real-time run.
-
Yun will work
with Dag to implement variable Sacramento parameters.
Ken discussed
status/results/recommendations from new EMC hourly/daily QC program for LDAS
forcing
-
zenith angle
error around sunset during portions of Jun‑Aug 99
-
examples/discussion
of occasional bad precipitation (nontrivial negative values)
-
discussion of
fixing past dates
EMC plan for
hourly/daily QC program for multi‑model LDAS GRIB output: Dag runs on a
routine basis for all groups. Each group should be familiar with the utility
program.
There are high
bias in Eta/EDAS 10‑meter winds. Ken presented EMCs fixes.
Ken showed the
first monthly comparisons of EDAS and NOAH‑LDAS modeled skin temperatures
vs GOES skin temperature retrievals over CONUS. There are obvious biases.
All
participants discussed Retrospective validation outline. The outline are shown
below.
RETROSPECTIVE
LDAS PROJECT OUTLINE
Datasets
Data sources
QC
Periods of high/low quality
Initialization
Forcing fields
contents
Precipitation
Downward solar
Downward longwave
Surface temperature
Surface humidity
Surface wind u/v components
Surface pressure
Analysis periods
1996-present
april 1999 - present
Yr 1 - 1-yr spin-up to april 2000
Yr 2 - re-start at april 1999 using april 2000
Analysis to be done on ncep sgi, results must be downloaded by month
because of NCEP data storage constraint
each group to delete their present multi-year binary output before
starting the re-analysis
once a week, full state variable binary restart file saved
all other output to be in grib
NCEP will run streamflow routing on selected basins.
1948 - present
Basin studies for
streamflow verification
Comparisons with RFC
products