# Presentation: 702124

## Workshop Objectives

***Workshop Objectives***
***[ Eric A. Smith -- NASA/GSFC ]***

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

**2nd International GPM Ground Validation Workshop**
**Eric A. Smith; NASA/Goddard Space Flight Center, Greenbelt, MD  20771**
**     ****[****eric.a.smith@nasa.gov;**** ****tel: 301-286-5770****;**** fax: 301-286-1626****]**
**27-30 September 2005; Taipei, Taiwan**

**GPM**

## Purpose: Ensure highest possible quality in GPM’s satellite precipitation measurement time series by: (a) obtaining quantitative measures of retrieval uncertainty throughout length of record, (b) providing continuous support to improvement of GPM’s standard precipitation retrieval algorithms, and (c) using GCM-RA, NWP, and HYDROMET modeling as part of GV toolkit though GV-measurement guided data assimilation.

***High Level Scientific Objectives:***
**Support improvement of satellite precipitation retrieval algorithms -- by providing GV measurements directly related to physical formulations and physics assumptions embedded in algorithm designs.**
**Establish quantitative uncertainties in GPM satellite precipitation retrievals using well-defined error metrics including -- (i) conditional bias errors (systematic departure from true average value), (ii) conditional precision errors (random fluctuation from true zero-bias average value), (iii) conditional spatial-temporal covariance errors (departure from true space-time lag-/auto-correlation structure), & (iv) any other scientifically useful metrics providing insight on GPM retrieval quality.**
**Seek improved understanding of underlying dynamical, thermodynamical, hydrological, macrophysical, and microphysical properties of precipitating storms throughout their life cycles -- by implementation of diverse GV measurement program, including development of new GV methodologies & new GV instruments.**

***Purpose & High Level Science Goals of International GPM Ground Validation (GV) Research Program?***

## Slide 3

## Main Objectives of

**	****Algorithm developers require variety of precipitation measurements from ground instruments and aircraft for direct comparison to their algorithm precipitation estimates -- plus additional remotely sensed and *****in situ***** measurements that support improvement of physical formulations and physics assumptions used in their algorithms -- measurements from, e.g., cloud microphysics laser-imaging systems, up-/down-viewing ground radiometers, specialized ground radars including Doppler profilers, impact and optical disdrometers, state-of-art precision rain gauges and dense gauge networks, state-parameter/moisture/wind profiling systems, etc.).**
**2.****	****Ensure System Integration of Data Acquisition from GPM GV Site Network by use of System Engineering Principles**
**	****Three types of GPM GV sites are envisaged: (1) Standard Sites, (2) Supersites, and (3) Regional (Virtual) Supersites. They will be funded and managed by owner institutions for specific purposes -- small number of which will be dedicated to GPM.  To ensure successful GV research program, we must develop data acquisition plan from individual sites in framework of “System of Sites” to ensure GPM’s GV requirements are met.  It is recommended that data acquisition process from “System of Sites” be developed according to principles of “System Engineering”.**
**3.****	****Develop Plan for Systematic Accumulation of “Experience Data” from Existing Sites to Ensure “Sensible” GPM GV Site Network Implementation Plan**
**	****GPM’s GV site network planning should be based on strengths and experience of participating individuals and institutions -- and thus requires systematic gathering of “experience data” -- data that are essential to “sensible” implementation & deployment of GV site network.**

***Main Objectives of***
***2nd International GPM GV Workshop?***

## How Workshop Will Accomplish These Objectives

**1.****	****1st segment of Workshop will consist of *****GPM Mission Status*****, *****Algorithms-Applications Requirements*****, and *****System Integration of Data Acquisition from GV Site Network*****.**
**2nd Segment of Workshop will consist of***** ******Working Group Meetings & Reports***** -- where meetings should focus on 3 main themes of workshop (i.e., algorithm developer requirements, integration of site data acquisition plan for site network, & accumulation of “experience data”) -- without restricting discussion to these themes.**
**3.****	****3rd Segment of Workshop will consist of *****Individual Reports Bearing On Site Experience*****.  Obtaining copies of these presentations is *****very important***** ****in synthesizing “experience data”.**