# Presentation: 548248

## Overview & Preliminary Planning

** ****1st GPM Workshop on Algorithms & Data Products**
**Eric A. Smith; NASA/Goddard Space Flight Center, Greenbelt, MD  20771**
**	****[tel: 301-286-5770;**** fax: 301-286-1626;**** ****easmith@pop900.gsfc.nasa.gov;**** ****http://gpmscience.gsfc.nasa.gov****]**
**March 12-13, 2002; Greenbelt, MD**

**Global Precipitation Measurement (GPM) Mission**
**An International Partnership &**
**Precipitation Satellite Constellation**
**for Research**
**on Global Water & Energy Cycle**
** **

**Overview & Preliminary Planning**

## Purpose of Workshop

*********.******	******Review & approve conceptual algorithm & data products architecture that enables TSDIS group to make progress now (Ziad Haddad, Chris Kummerow, Bob Meneghini, John Stout, Wai-K. Tao).***
*********Connect algorithm/data products program to GV program & continuous error characterization, noting separation of science from requirements (Sandra Yuter).***
*********V******.******	******Foreword three (3) important recommendations to GPM instrument manager (Mark Flaming) concerning specifications for core satellite radiometer, i.e., GPM Microwave Imager (GMI): ******(a) exact frequency definitions; (b) contiguity requirements & implications; (c) priorities for high frequency channels -- assuming they are provided.***

***Purpose of Workshop***

## Primary IPDS Elements

***Advanced Data System***
***Data Archive & Distribution***
***CalVal Simulator***
***Science Guidance***

**Integrated Precipitation Data Plan**
**(IPDS): Accelerated Plan**

## IPDS Architecture

**IPDS Architecture**

**TRMM**

**Geo IR**

**Testbed I/F Simulator**

**Dual Frequency ****DPR ****Synthesizer**

**World Precipitation**
**Data System**

**Experimental**
**Rain Products**
**& Error**
**   ****Characterization**

**Validation / Error Estimates**

**DAAC**

**Field Campaigns**

**Ground Instruments**

**CalVal**
**Simulator**

**Evolving Advanced GPM**
** ****Algorithms**

**1997**

**1998**

**1999**

**2000**

**2001**

**2002**

**2003**

**2004**

**2005**

**2006**

**2007**

**1996**

**1995**

**Precipitation Algorithm Release**

**V0**

**V1**

**V2**

**V3**

**V4**

**V5**

**V6**

**V7**

**V8**

**V9**

**V6g**

**V7g**

**V8g**

**2008**

**2009**

**TRMM**

**GPM**

**Beta**

**Science Guidance**

**Testbed**
**I/F Std’s**

**NewDISS Formulation Initiative**

**Megha Trop**

**EGPM**

**Evolution**

**Tools & Data Formats**

**Generic I/F**

**GHCC **
**SSMIS/AMSR**

**SAN Interface**

## Strategy for Populating Constellation

**TBD**

- b

**(ATMI/DPR)**

**GPM Core**

**DMSP-F18/20**

**DMSP-F19**

**GCOM-B1**

**(SSMIS)**

**(SSMIS)**

**(AMSR-FO)**

**N-GPM**

**E-GPM**

**FY-3**

**(E-PMR)**

**Reference**

**Co-Op Drone Partners**

**NPOESS-1**

**NPOESS-2**

**NPOESS-3**

**(CMIS)**

**(CMIS)**

**(CMIS)**

**MEGHA**
**TROPIQUES**

**(MADRAS)**

- Optimization and Compromise

**Potential New Drones/Partners**

**Strategy for Populating Constellation**

**NPOESS-Lite**

**(CMIS)**

**(C-PMR)**

**(N-PMR)**

**TRMM**

**AQUA**

**ADEOS-II**

**DMSP-F17**

**DMSP-F16**

## GPM Operations & Data Flow

- Virtual
**Ground**
- Station

**Core**

**NASA Drone**

**Partner Drone**

**DMSP**

**TDRSS**

**GCOM**

**Command**
**Telemetry**

**White Sands**

**IPO Operations**

**NASDA Operations**

**GHCC/MSFC**

**GPM Partner**
**Mission**
**Operations/Data**
**Center**

**GSFC Global Precipitation**
**Data Center (GPDC)**

**Near**
**Real-time**
**Rainfall**

**3-hr**
**Rain**
**Map**

**Climate**
**Data**

**Per Orbit**

**IR Data (GOES)**

**AMSU (POES)**

**Per Orbit**

**Ancillary Data Streams**

**GP Data Broadcast**
**Network**

**Global Precipitation Network**

**Continuous Real Time Data Links**
**Once Per Orbit Data Links**
**Command/Telemetry Links**

**Continuous**
**Science Data**

**NASA**
**Mission**
**Operations**
**Center**

**Coordination**

**Potential**
**ESA (E-GPM)**
**& ASI (I-GPM)**
**Partnerships**

**EOSDIS**

***GPM Operations & Data Flow***

## Tracibility to ESE's Strategic Plan

**I. How is global Earth system changing? ****(Variability)**
**1.****  How are global precip, evap, & water cycling changing?**
- 2.  How is global ocean circulation varying on interannual, decadal, & longer time scales?
- 3.  How are global ecosystems changing?
- 4.  How is stratospheric ozone changing, as _x0008_abundance of ozone-destroying chemicals
-      decreases &  new  substitutes increases?
- 5.  What changes are occurring in mass of Earth’s ice cover?
- 6.  What are motions of Earth & its interior, & what information can be inferred about its
-       internal processes?
**II. What are primary forcings of Earth system?  ****(Forcing)**
- 1.  What trends in atmospheric constituents & solar radiation are driving global climate?
- 2.  What changes are occurring in global land cover & land use, & what are their causes?
- 3.  How is Earth’s surface being transformed & how can such information be used to
-        predict future changes?
**III.  How does Earth system respond to natural & human-induced changes?   ****(Response)**
**1.****  What are effects of clouds & surf hydrology on climate?**
- 2.  How do ecosystems respond to & affect global environmental change & carbon cycle?
- 3.  How can climate variations induce changes  in global ocean circulation?
- 4.  How do stratospheric trace constituents respond to change in climate & atmospheric composition?
- 5.  How is global sea level affected by climate change?
- 6.  What are effects of regional pollution on global atmosphere, & effects of global chemical & climate changes on regional air quality?

**How is Earth changing and what are consequences for life on Earth?**

**Tracibility to ESE's Strategic Plan**

**IV.  What are consequences of change in Earth system for civilization?   ****(Consequences)**
**1.****  How are variations in local weather, precipitation & water resources related to global climate variation?**
- 2.  What are consequences of land cover & use change for sustainability of ecosystems & economic productivity?
- 3.  What are consequences of climate & sea level changes & increased human activities on coastal regions?
**V.  How well can we predict future changes in the Earth system?   ****(Prediction)**
**1.****  How can weather forecast duration & reliability be improved by new space obs, data assim, & modeling?**
**2.****  How well can transient climate variations be understood & predicted?**
**3.****  How well can long-term climatic trends be assessed & predicted?**
- 4.  How well can future atmospheric chemical impacts on ozone and climate be predicted?
- 5.  How well can cycling of carbon through Earth system be modeled, & how reliable are predictions of future atmospheric concentrations of carbon dioxide & methane by these models?

**Asrar, G., J.A. Kaye, & P. Morel, 2001:  NASA Research Strategy for Earth System Science: Climate Component.  *****Bull. Amer. Meteorol. Soc.*****, ****82****, 1309-1329.**

##  Improved Climate  Predictions: through progress in quantifying trends & space-time variations of rainfall & associated error bars in conjunction with improvements in achieving water budget closure from low to high latitudes -- plus focused GCM research on advanced understanding of relationship between rain microphysics/latent heating/DSD properties & climate variations as mediated by accompanying accelerations of both atmospheric & surface branches of global water cycle.

** ****Improved Weather Predictions:**** ****through accurate, precise, frequent & globally distributed measurements of instantaneous rainrate & latent heat release -- ****plus focused research on more advanced NWP techniques in satellite precipitation assimilation & error characterization of precipitation retrievals.**
** ****Improved Hydrological Predictions:**** ****through frequent sampling & complete continental coverage of high resolution precipitation measurements including snowfall -- ****plus focused research on more innovative designs in hydrometeorological modeling emphasizing hazardous flood forecasting, seasonal draught-flood outlooks, & fresh water resources prediction.**

**GPM Mission is Being Formulated within Context of Global Water & Energy Cycle**
**with Foremost Science Goals Focusing On**

## Is Water Cycle Accelerating?

## TRMM-retrieved Radar & Radiometer Rainfall Anomaly Time Series with MSU-retrieved ice index (DCI)

**TRMM-retrieved Radar & Radiometer Rainfall Anomaly Time Series with MSU-retrieved ice index (DCI)**
- (**anomalies normalized by annual mean**)

**(F.R. Robertson; GHCC)**

**Notes:**
Time series of tropical ocean only rainfall anomalies from 2-year period.  Normalized by the mean for this period so they are in terms of fractional departures.

## GPM Mission's

***Atmosphere***

***Water***

***Land***

***Weather, Climate, &***
***Hydrology***

***(1) ******Global Water & Energy Cycle Processes & Modeling: Role of Precipitation ******(Prof. Eric Wood, Princeton)***
***(2) ******Climate System Variability & Climate Diagnostics: Role of Precipitation ******(Dr. Franklin Robertson, NASA/MSFC @ GHCC)***
***(3)****** ******Climate Model Simulations & Reanalysis, NWP Techniques, & Data Assimilation: Role of Precipitation ******(Dr. Arthur Hou, NASA/GSFC)***
***(4) ******Land Surface Hydrology & Hydrometeorological Modeling: Role of Precipitation ******(Dr. Harry Cooper, Fla. State Univ.)***
***(5) ******Ocean Surface & Marine Boundary Layer Processes: Role of Precipitation ******(Dr. Vikram Mehta, NASA/GSFC)***
***(6) ******Coupled Cloud-Radiation Modeling: Physical Interpretation of Precipitation Processes ******(Prof. Gregory Tripoli, Univ. Wis. & Dr. Wei-K. Tao, NASA/GSFC)***
***(7a) ******Precipitation Retrieval: Reference Radar-Radiometer Core Algorithm & Radar Simulator ******(Dr. Ziad Haddad, NASA/JPL)***
***(7b) ******Precipitation Retrieval: Parametric Radiometer Constellation Algorithm & Radiometer Simulator ******(Prof. Christian Kummerow, Colo. State Univ.)***
***(7c) ******Precipitation Retrieval: Cal Transfer, Bias Removal, & Merged Products ******(Prof. Eric Smith, NASA/GSFC)***
***(8) ******Calibration & Validation of Satellite Precipitation Measurements ******(Dr. Sandra Yuter & Prof. Robert Houze, Univ. Washington)***
***(9) ******Forecast Apps, Public Service, TV, & Educational Outreach ******(Dr. Marshall Shepherd, NASA/GSFC)***

**GPM Mission's**
**Nine (9) Science Themes**

**USGCRP WCSG, 2001:  A plan for a new science initiative on the global water cycle.  *****UCAR Report.*****, sponsored by USDA, DOE, NASA, NOAA, NSF, USGS, ACE, BREC, & EPA, 118 pp.**

## GPM Disciplinary Research Themes, Science

**2**

**3**

**4**

***GPM Disciplinary Research Themes, Science***
***Requirement Groups, & Main Provisional Science Objectives***

**5**

**6**

**7a**

**7b**

**7c**

**8**

**1**

**1**

**9**

## Proposed GPM Precipitation Products

*********.  Level 3 Grid Products (modification to TRMM)***
***∑******  ******arithmetically consistent succession:***
***    ******(1) 3-hourly @ 0.1 x 0.1 deg;  (2) daily       @ .25 x .25 deg;***
***     ******(3) pentad     @ 1.0 x 1.0 deg; (4) monthly  @ 5.0  x 5.0 deg***
***∑******  ******simplified & integrated parameter set:***
***   ******(1) surface rainrate/rainfall & grid variance; (2) convective-stratiform separation;***
***	******(3) bulk DSD parameters; (4) latent heating profile; (5) confidence index***
***∑******  ******four (4) types of retrieval results ordered by retrieval quality:***
***   ******(1) core sat result (combined DPR - GMI);    (2)  constellation sat result (rain radiometers)***
***   ******(3) non-rain radiometer result (e.g., AMSU); (4)  geo-infrared result (******GOES, GMS, METEOSAT, MSG******)***
*********Full Resolution Pixel Tables (extension to TRMM)***
***∑******  ******tabulates all instantaneous rain pixels from all satellite sources within***
***    ******individual 3-hourly 0.1 x 0.1 deg grid elements, identified in space & time***
*********V************Level 4 Scale Invariant Blended Products (new)***
***∑******  ******properly transformed to constant space-time scales***

***Proposed GPM Precipitation Products***

**Goal is relatively seamless transition of precipitation products from TRMM to GPM eras, thus minimizing mission change impacts on science community.**

## How is Seamlessness Achieved?

*********.******	******Level 2 Swath Products:***
***Mostly same procedures & definitions, but with greater emphasis on accuracy of instantaneous retrievals & validation of "unfolded" physical algorithms ******-- ******this is strictly business of science team coordinated with TSDIS******.***
*********.******	******Level 3 Grid Products & Full Resolution Pixel Tables:*** ***Modified procedures & definitions ******-- ******this is strictly business of TSDIS because these products are directly derivable from level 2 products, should be user-friendly, & should be arithmetically consistent******.***
*********V************Level 4 Scale Invariant Blended/Gridded Products: ******New procedures & definitions ******-- ******this is a research problem to be addressed by science team and to be implemented on TSDIS when properly mature.***

***How is Seamlessness Achieved?***

## Accelerated Algorithm Development

**1.  Design & test GPM-era "precipitation product" generation system, as continuation of level-1 & level-2 "algorithm version" system adopted for TRMM, to enable seamless product transition from TRMM-era to GPM-era ****[GPM-era products will eventually be brought on-line for routine processing based on ****approval of**** ****"Integrated Precipitation Science Team"****]****.**
**2.  Develop, code, & test three (3) main new GPM-era precipitation retrieval algorithms: (i) level-2 reference DPR-GMI combined, (ii) level-2 parametric PMW radiometer, & (iii) level-3 merged-gridded products at time-space resolutions of:**
**                 ****(a) 3-hour / 0.1'deg  (b) 1-day / 0.25'deg  (c) 5-day / 0.5'deg  (d) 1-month / 5.0'deg**
**to determine computational performance in TSDIS / GPDC environment -- to be ready for implementation in late TRMM era ****[advanced GPM algorithms will ****not be vulnerable to drop-outs**** of any particular satellite, instrument, or channel -- ****including core satellite instruments****]****.**
**3.  Develop level-3 merged-gridded products at hierarchy of above space-time scales, all arithmetically consistent, containing 5 types of results:**
**    ****(a) DPR-GMI combined result [#allpix, aveRR****allrain**** , sigRR****allrain**** , #convpix, aveRR****conv ****, sigRR****conv ****,**
**           ****#stratpix, aveRR****strat**** , sigRR****strat**** , #unknpix, aveRR****unkn**** , sigRR****unkn**** , confindexREF, LHREF(4), DSD(3)]**
**    ****(b) constellation rain radiometer result [#allpix, aveRR****all**** , sigRR****all**** , #convpix, aveRR****conv ****, sigRR****conv ****,**
**           ****#stratpix, aveRR****strat**** , sigRR****strat**** , #unknpix, aveRR****unkn**** , sigRR****unkn**** , confindexCON, LHCON(4)]**
**    ****(c) non-rain radiometer (e.g., AMSU) result [#allpix, #rainpix, aveRR****rain****, sigRR****rain**** , confindexNRR]**
**    ****(d) GEO IR result [#allpix, #rainpix, aveRR****rain**** , sigRR****rain**** , confindexIR]**
**    ****(e) merged-weighted combination of above 4 results [mergeRR , confindexMERGE]**
**4. Develop pixel-level precipitation table product (sattype, time, lat, lon, RR, raintype, confindex) using all existing satellite rain sources, with pointers to "gridded" 3-hourly level-3 product, to enable detailed/high resolution space-time analysis ****[must not break TRMM paradigm that precipitation products are sized for "reasonable" communications & computer analysis efficiency, i.e., ****"no Huge & Unwieldy files"****]****.**

## Scientific Challenges for GPM Mission

**1.****	****Shift *****intellectual inquiry paradigm***** from "curiosity driven" to "quintessential problem driven" -- through GPM science team working group coordination.**
**2.****	****Shift *****research paradigm***** from "measuring takes precedent" to  "prediction takes precedent" -- through mandate for GPM science team.**
**3.****	****Shift *****derived products paradigm***** ****(e.g., latent heating, DSDs, macro/microphysical cloud properties, error characterization, solid precipitation, vertical rain mass flux)**** from "cautious release" to  "aggressive release" -- through modeler involvement in product assessment.**
**4.****	****Shift *****fast delivery data paradigm***** from "only operational users need them" to "research users need them too" -- through transfer of  specialized data products from GPM-WPDC to research partners conducting prediction experiments.**
**5.****	****Shift *****validation paradigm***** from "comparison scatter diagrams" to  "physical error modeling" involving inverting flow of data from & to validation center and deploying new ground instruments at various validation supersites.**
**6.****	****Shift *****cloud/precipitation paradigm***** from "these are separate & distinct problems" to  "this is microphysical continuum" leading to integrated cloud-precipitation missions, research programs, textbooks, and teaching.**

***Coordinate GPM Science Implementation Plan with GEWEX***

## Backup Slides

## Error Characterization 1

**based on:**
** ****∑****  ****physical error model ****( ****passive-active RTE model**** )**
**∑****  ****matched satellite radiometer/radar instrument**
**    ****on ground with continuous calibration ****(**** ****eyeball**** ****)**
**∑****  ****independent**** measurements of observed inputs**
**   ****needed for error model**

**Bias & Bias Uncertainty**

- all retrievals from constellation radiometers & other satellite instruments are bias adjusted according to bias estimate for reference algorithm from core satellite

## Error Characterization 2

**based on:**
** ****∑**** ****ground Radars ****( ****polarization diversity enables**
**    ****cross-checking**** )**
**∑**** ****high-quality, uniformly distributed, dense,**
** ****& hi-frequency sampled raingage networks**

**Precision & Space-Time**
**Error Covariance**

***Error Characterization 2***

## Principles of Physical Error Modeling

**Radiance Tube**

- TOA

**meteorology & microphysics characterization volume observed by independent instruments**
**∑**** ****Doppler Profilers (2)**
**   ****for precip/cloud hydrometeor profiles**
**∑**** ****Radiosonde**
**   ****for T(z)/q(z) profiles**
**∑**** ****Downward-pointing Radiometer**
**   ****for surface emissivity**
**∑**** ****Raingage & Disdrometer Network**
**   ****for cross-checking**

- TOA

- Surface

***Principles of Physical Error Modeling***

**matched core satellite radiometer/Radar ground instrument “Eyeball”**
**[with active target calibration]**

**∑**** ****difference between retrieved & RTE modeled hydrometeor profiles yields retrieval "bias"**
**∑**** ****mismatch in 2-ended RTE model solution based on absorption-scattering properties assigned to characterization volume  yields retrieval "bias uncertainty"**

**Note: ground Radars & regional raingage networks in conjunction with coincident satellite retrievals can generate "space-time correlation structure functions" & "space-time error covariance matrices".**

- Surface

## GPM Validation Strategy

**Confidence**
**sanity checks**

**GPM**
**Satellite**
**Data**
**Streams**

**Continuous**
**Synthesis**
**∑**** ****error variances**
**∑**** ****precip trends**

**Calibration**

**High Latitude Snow**

**Research**
**Quality**
**Data**

**Algorithm**
**Improvements**

**Research**
**∑**** ****cloud macrophysics**
**∑**** ****cloud microphysics**
**∑**** ****cloud-radiation**
**       ****modeling**

**FC Data**

**Supersite Products**

**II. GPM Supersites**
****** ****Basic Rainfall Validation**
**hi-lo res gauge/disdrometer networks**
**polarametric Radar system**
****** ****Accurate Physical Validation**
**scientists & technicians staff**
**data acquisition & computer facility**
**meteorological sensor system**
**upfacing multifreq radiometer system**
**D****o****/DSD variability/vertical structure**
**convective/stratiform partitioning**

**III. GPM Field Campaigns**
****** ****GPM Supersites**
**cloud/ precip/radiation/dynamics  processes**
****** ****GPM Alg Problem/Bias Regions**
**targeted to specific problems**

**I. ****Basic Rainfall Validation**
**∑**** ****Raingauges/Radars**
-        **new/existing gauge networks**
**       ****new/existing radar networks**

## Potential GPM Validation Sites

***Potential GPM Validation Sites***

- Supersite

- Regional Raingage Site

- Supersite & Regional Raingage Site

- Australia

- NASA Ocean

- Japan

- South Korea

- India

- France (Niger & Benin)

- Italy

- Germany

- Brazil

- England

- Spain

- NASA KSC

- NASA Land

- Canada

- Taiwan

- ARM/UOK