Use Of NPP Data In The Joint Center For Satellite Data Assimilation Lars Peter Riishojgaard, JCSDA Director IGARSS July
Overview Introduction to JCSDA Weather prediction and satellite data Motivation for R2O, NPP Preparation for new sensors NPP-related activities Summary IGARSS July
IGARSS JCSDA History NASA/NOAA collaboration (Uccellini, Einaudi, Purdom, McDonald) initiated in 2000 Concern about US leadership in satellite data technology and instrumentation not replicated in applications, e.g. NWP GMAO (DAO), NCEP and STAR (ORA) Emphasis on balanced approach involving Modeling Computing Observational data Inclusion of DoD (NRL Monterey and AFWA) triggered by IPO sponsorship of JCSDA starting in 2002 First permanent Director hired in 2004 (John Le Marshall) Memorandum of Agreement signed May 2008 July
4 NASA/Earth Science Division US Navy/Oceanographer and Navigator of the Navy and NRL NOAA/NESDISNOAA/NWS NOAA/OAR US Air Force/Director of Weather Mission: …to accelerate and improve the quantitative use of research and operational satellite data in weather, ocean, climate and environmental analysis and prediction models. Vision: An interagency partnership working to become a world leader in applying satellite data and research to operational goals in environmental analysis and prediction JCSDA Partners, Vision, Mission IGARSS 2011 July
IGARSS JCSDA Science Priorities Radiative Transfer Modeling (CRTM) Preparation for assimilation of data from new instruments Clouds and precipitation Assimilation of land surface observations Assimilation of ocean surface observations Atmospheric composition; chemistry and aerosol Driving the activities of the Joint Center since 2001, approved by the Science Steering Committee Overarching goal: Help the operational services improve the quality of their prediction products via improved and accelerated use of satellite data and related research July
Slide 6 Satellite data now account for most of the skill Impact of GOS components on 24-h ECMWF Global Forecast skill (courtesy of Erik Andersson, ECMWF)
500 hPa geopotential height anomaly correction from 01/09/ /22/ hPa geopotential height anomaly correction from 01/09/ /22/2008
IGARSS 2011 Weather Prediction and the US Economy; A Macroscopic View Department of Commerce: “20% of overall US economy is weather sensitive”: ~$3 trillion/year –Impact to air and surface transportation, agriculture, construction, energy production and distribution, etc. Assume that half of this is “forecast sensitive”: $1.5 trillion/year Assume that the potential savings due to weather forecasting amount to 5% of the “forecast sensitive total”: ~$75B/year July
IGARSS 2011 … a Macroscopic View … (II) Define now –“No forecast information” = 0 h useful forecast range –“Perfect forecast” = 336 h useful forecast forecast range (two weeks traditonally used as limit of predictability) Next, assume that the potential savings up to the maximum of $75B are distributed linearly over the achieved forecast range for the global NWP system: –$75B/336h = $223M/hr This implies that the value to the United States economy of weather observations, dissemination, forecast products and services is >200M per hour of forecast range per year ! July
NPP-related efforts in the Joint Center 1. Improved use of legacy data CrIS precursors (AIRS, IASI) ATMS precursors (AMSU) 2. CRTM modifications 3. Data flow/ingest of proxy data 4. Impact Experiments 5. Post-launch activities July IGARSS
Improved use of NPP precursor data; IR AIRS/IASI water vapor channel improvement Use of cloudy radiances Surface emissivity (land) Assimilation methodology studies Additional channels July IGARSS
Forecast impact of assimilation of AIRS cloud-cleared radiances July IGARSS
Improved use of NPP precursor data; Microwave Ongoing CRTM improvements Surface emissivity, especially over snow, ice,… Emissivity models Databases Measurements affected by precipitation July IGARSS
July IGARSS Example of MW emissivity study (courtesy of Fuzhong Weng, NESDIS/STAR)
NPP Proxy Data CrIS and ATMS proxy data generated by NESDIS on a routine basis (Barnet) Based on GFS model output, SARTA radiative transfer model applied to model profiles Streamed to JCSDA, ready for testing July IGARSS
CRTM status CRTM ready for NPP sensors CrIS ATMS VIIRS CRTM v. 2.1 released earlier this year Additional sensors Computational efficiency July IGARSS
500 hPa geopotential height anomaly correction from 01/09/ /22/ hPa geopotential height anomaly correction from 01/09/ /22/2008
Observing System Simulation Experiments for NPP Level 1 Experiments with simulated (proxy) data from CrIS, ATMS along with existing data used in operations Purpose here is to test data flow and data ingest rather than data impact Level 2 Using the Joint OSSE system All data simulated; purpose is to assess and optimize data impact July IGARSS
Post-launch activities Passive monitoring Observation minus forecast residuals monitored This effectively validates NPP data against the rest of the Global Observing System Active assimilation, off-line mode, impact assessment Operational assimilation July IGARSS
Summary The economic impact of Numerical Weather Prediction and related activities are estimated to range in the tens of $B/year for the US alone Satellite data are critical for NWP Upcoming launch of NPP marks the entry of a new generation of operational meteorological satellites for the US The Joint Center is heavily involved in preparing US operational users to benefit from these new data as soon as possible after launch IGARSS July