global precipitation measurement (gpm) mission data and data access
DESCRIPTION
Global Precipitation Measurement (GPM) Mission Data and Data Access NASA Precipitation Processing System (PPS). Erich Franz Stocker ( [email protected] ) PPS Project Manager/Software Architect GPM Deputy Project Scientist for Data. GPM Key Data Dates. - PowerPoint PPT PresentationTRANSCRIPT
1EGU 2014-Vienna Austria, April 30, 2014
Erich Franz Stocker ([email protected])PPS Project Manager/Software ArchitectGPM Deputy Project Scientist for Data
Global Precipitation Measurement (GPM) Mission Data and Data AccessNASA Precipitation Processing System (PPS)
2EGU 2014-Vienna Austria, April 30, 2014
3EGU 2014-Vienna Austria, April 30, 2014
GPM Key Data Dates• February 28, 2014 3:30AM (JST) GPM Core Observatory
launch from Tanegashima Space Center, Japan• March 4, 2014 GMI commanded to science observation
mode and first data received• March 8, 2014 DPR commanded to science observation
mode and first data received• March 21, 2014 GMI L1, L2 near-realtime (NRT) and L1,
L2, L3 science standard data made available to set of early data adopters
• April 2, 2014 DPR L2 NRT and L2 and L3 science standard data made available to set of early data adopters
• April 2, 2014 Combined GMI/DPR L2 NRT and L2 and L3 science standard data made available to set of early data adopters
• Current GMI, DPR and Combined data version is V01D both NRT and standard science
4EGU 2014-Vienna Austria, April 30, 2014
Data Release
• End of June 2014 GMI data release to the international Precipitation Measurement Missions (PMM) science team
• End of July 2014 DPR data release to the international PMM science team
• End of August 2014 General public release • End of November 2014 General public release of new
merged radiometer product (IMERG)
5EGU 2014-Vienna Austria, April 30, 2014
NRT GPM Core Data Products
Processing Level
Sat/Inst/Alg Size Latency Key Parameters
1B GPM/GMI 5 min <= 1Hr 90% Brightness Temperature-Tb
1C GPM/GMI 5 min <=1Hr ,90% Tb (future 1C reference)
1CR GPM/GMI 5 min <- 1Hr, 90% Intercalibrated Tb with matched HF and LF pixels
2A GPM/GMI/GPROF 5 min <=1Hr 90% Precipitation/TPW
2A Ku GPM/DPR/Ku 30 min
<=180 min Reflectivities/3D Precipitation
2A Ka GPM/DPR/Ka 30 min
<=180 min Reflectivities/3D Precipitation
2A DPR GPM/DPR/DPR 30min <= 180min Dual Frequency retrievals: reflectivities/3D
precipitation2B
GMI/DPRGPM/GMI-DPR 30
min<=180 min 90% Combined GMI/DPR
retrieval. 3D Precipitation3 Merged
Radiometers/IRHalf-hour
Early – 4 hoursLate – 8 hours
.1 deg x .1 deg global surface precipitation
6EGU 2014-Vienna Austria, April 30, 2014
1CR
7EGU 2014-Vienna Austria, April 30, 2014
NRT Constellation Products
Processing Level
Sat/Inst/Alg Size Latency Key Parameters
1C Metop B/MHSNoaa 18/MHSNoaa 19/MHS
As receive
d
Provider dependent
Intercalibrated Tb
1C MT/SAPHIR As receive
d
Provider Intercalibrated Tb
1C NPP/ATMS 1 Hr Provider Intercalibrated Tb
1C F16/SSMISF17/SSMISF18/SSMIS
As receive
d
Provider Intercalibrated Tb
1C TRMM/TMI TDRSS <=180 min Reference Tb1C GCOM-W/AMSR2 orbit ~120min Intercalibrated Tb2A GPROF /MHS
SAPHIRATMSSSMIS
TMIAMSR2
Same as 1C
Same as 1C Precipitation/TPW
8EGU 2014-Vienna Austria, April 30, 2014
Standard GPM Core Science Swath Products
Processing Level
Sat/Inst/Alg Size Key Parameters
1B GPM/GMI GPM orbit (Gorbit*)
Brightness Temperature-Tb
1C GPM/GMI Gorbit Tb (future reference)1CR GPM/GMI Gorbit Tb with matched HF and
LF footprint2A GPM/GMI/GPROF Gorbit Precipitation/TPW
2A Ku GPM/DPR/Ku Gorbit Reflectivities/3D Precipitation
2A Ka GPM/DPR/Ka Gorbit Reflectivities/3D Precipitation
2A DPR GPM/DPR/ Gorbit Dual Frequency Retrievals. 3D precipitation
2B GMI/DPR
GPM/GMI-DPR Gorbit GMI-DPR retrieval. 3D Precipitation
* Gorbit is the GPM orbit calculated from the southern most point back to the southern most point
9EGU 2014-Vienna Austria, April 30, 2014
Standard GPM Core Gridded Products
Processing Level
Sat/Inst/Alg Size Key Parameters
3A GPM/GMI/GPROF 0.25 deg x 0.25 deg
Daily/monthly
Precipitation
3A GPM/DPR 0.25 deg x 0.25 deg
Daily
PrecipitationAscending/Descending
separate3A GPM/DPR 0.25 deg x 0.25
degMonthly
Precipitation
3B combined
GPM/GMI-DPR 0.25 deg x 0.25 deg
Daily/monthly
Precipitation
3B Merged Merged Radiometers 0.10 deg x 0.10 deg
Half-hr/monthly
Gauge adjusted global precipitation
10EGU 2014-Vienna Austria, April 30, 2014
Standard Constellation Data ProductsProcessing Level
Sat/Inst/Alg Size Key Parameters
1C Metop B/MHSNoaa 18/MHSNoaa 19/MHS
GPM orbit
(Gorbit)
Intercalibrated Tb
1C MT/SAPHIR Gorbit Intercalibrated Tb1C NPP/ATMS Gorbit Intercalibrated Tb
1C F16/SSMISF17/SSMISF18/SSMIS
Gorbit Intercalibrated Tb
1C TRMM/TMI Gorbit Reference Tb1C GCOM-W/AMSR2 Gorbit Intercalibrated Tb2A GPROF /MHS
SAPHIRATMSSSMIS
TMIAMSR2
Same as 1C
Precipitation/TPW
3A All instruments with GPROF 2A
Dailymonthl
y
0.25 deg x 0.25 degPrecipitation
11EGU 2014-Vienna Austria, April 30, 2014
Status of GPM Data Products-1• Geolocation
– Location on the ground reported within requirements– On April 19 Attitude Control System engineers reported an alignment error between
start tracker and spacecraft leading to ~0.3 degree peak to peak attitude error (mostly roll)• This does have an impact on incidence angles which affect Tb calculation• New table scheduled to be uploaded April 25• Data products will be adjusted as part of reprocessing for the PMM data release
• GMI L1 products– Reasonably well calibrated (meets requirements specifications)– Small calibration changes in April that included in version V01D– Close to TMI calibration– Some RFI issues in 10 GHz and 18GHz channels (approach to flag and mitigate
currently being examined.)• GPROF retrieval products
– Saw more specific information in Dr. Kummerow’s presentation– Currently using initial non GPM a priori databases – New database approach for over land retrievals working reasonably well– Currently producing GPROF retrieval for partner imagers and testing sounders– Early state: some areas during really well and others not – Will need about one year of stable GMI L1C and GMI-DPR Level 2B data to establish
physically based a priori databases for the GPROF retrievals for the radiometers
12EGU 2014-Vienna Austria, April 30, 2014
Status of GPM Data Products -2• Ku/Ka L1B –radar powers
– Have completed several external and internal calibrations– Have verified phase shifter commands– Reasonably well calibrated for this stage of the mission– Providing acceptable input for the radar L2 algorithms
• Ku/Ka/DPR-retrievals– L2 are providing reasonable retrievals again at the early stage where better in some
areas than in others– Matching of Ku/Ka pixels working – Some issues are being worked by JAXA engineers and DPR algorithm team
• Combined GMI-DPR– Very early stage of development– Working on dealing with data input issues– Currently still in the experimental stage
• IMERG (merged radiometer product)– Not being currently produced– Need stable GPROF retrievals for sounders as well as imagers– Currently in internal testing– Usually lags 3 to 4 months after stable L2 GPROF retrievals.
13EGU 2014-Vienna Austria, April 30, 2014
Sample Images of GMI and DPR
14EGU 2014-Vienna Austria, April 30, 2014
GPM Special Products• Daily gridded text products (like TRMM 3G68)
– 0.1 deg x 0.1 degree– Contains:
• GMI GPROF surface precipitation• Ku near-surface precipitation• Ka near-surface precipitation• DPR match swath near-surface precipitation• GMI-DPR Combined surface precipition
– ASCII with line terminator being LF character• GIS compatible files for IMERG
– TIFF (precipitation) with world files for metadata– Precipitation in TIFF is scaled integer– Half-hourly, 1day, 3 day and 7 day accumulations
15EGU 2014-Vienna Austria, April 30, 2014
Accessing GPM Data• Must register an email.
– registration.pps.eosdis.nasa.gov– Receive an email and click to confirm– Can specify interest in either standard science, NRT or both
• Can do ftp to the archive using your registered email as user name and password• Can use a query/order web interface
– storm-pps.gsfc.nasa.gov or storm-pps.pps.eosdis.nasa.gov– Can query, place orders for specific products, or establish standing orders which will
be fulfilled as products are generated– Can subset swath products and get only the subsets specified
• Geographically• Parameter (e.g. just include geolocation and surface precipitation)• Or both together• Currently limited as to the number orderable to keep within scope
– Can establish standing orders for subsets – Can see browse images of the orbit to help in ordering decisions– Can look through the data product online
• File specifications and algorithm theoretical basis documents (ATBD)– pps.gsfc.nasa.gov/GPMprelimdocs.html
16EGU 2014-Vienna Austria, April 30, 2014
Tools and Services• THOR
– Tool for looking at GPM data products – Includes functionality for making images including 3D images– IDL based but IDL not required– Available for: Linux, Windows, Mac OS– http://pps.gsfc.nasa.gov/thorrelease.html
• Subsetting available for multiple years (STORM currently limits) – [email protected]– [email protected]– Includes setting up subsets to support field campaigns
• 3 Hr Presentation (Data and data access)– Includes
• More detailed data description,strengths,limitations and status• HDF5 format and tools for accessing• Useful documentation• Accessing data including the writing of scripts for automated access• Use of THOR, STORM
– Can with planning offer the tutorial at Universities and agencies – After a couple of presentations to get user feedback will package the presentation– Contact: [email protected]