Combined Geo/Leo High Latitude Atmospheric Motion Vectors

1. 2009 GOES-R Risk Reduction Proposal for Combined Geo/Leo High Latitude Atmospheric Motion Vectors Matthew Lazzara – PI (SSEC) Dave Santek (CIMSS) Chris Velden (CIMSS) Jeff Key (STAR) Jaime Daniels (STAR) SSEC - Space Science and Engineering Center, University of Wisconsin-Madison CIMSS - Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin-Madison STAR - Center for Satellite Applications & Research

2. Background Coverage of satellite-derived Atmospheric Motion Vectors (AMV): • Geostationary satellites: equatorward of ~60° latitude • Polar satellites: poleward of ~70° latitude NWP centers: the polar jet stream can be located in this gap; improper model initialization can lead to errors in the forecasts. CIMSS research: the addition of the wind information is important in this region. From ECMWF Developing novel ways to fill this AMV-void gap is the next step in providing complete wind coverage for the NWP applications.

3. Project Summary We propose toexplore the prospect of generating AMVs in the geographic gap from 60° to 70° N/S latitudes using both geostationary and polar-orbiting satellites. This will require an advanced image compositing technique to blend the data from a variety of satellites with differences in calibration, viewing geometry, and temporal offsets. The resulting images would be composites of the Geo (GOES East and West, Meteosat-7 and -9, FY-2C, MTSAT-1R, Kalpana-1) and Leo satellites (NOAA-15 through NOAA-19, Metop-A, NASA’s Terra and Aqua). 50o 70o Example of winds from composite GEO/LEO satellite data.

4. Relevance to GOES-R The GOES-R Advanced Baseline Imager (ABI) will be a critical component of this composite approach because of the improved spatial resolution over the current GOES imager: • ABI pixel size at 70° latitude: 11.2 x 2.2 km • Current GOES imager at 60° latitude: 11.7 x 2.5 km This should translate to: • Superior fidelity in the imagery in the latitudinal gap (within the longitudinal coverage of the GOES-R series) • Improved composite imagery for deriving the AMVs. AMV Cloud Height: • The additional channels available on the ABI may also provide better cloud height assignment for the AMVs through new multispectral techniques. • However, some of the available proxy satellite data (GOES, AVHRR, etc.) will not permit us to investigate and evaluate these new techniques.

5. Proxy Data The proof of concept for this project was done using a modified version of the Antarctic Meteorological Research Center’s (AMRC/SSEC) composite satellite imagery. Additional work is needed to include other satellites and to simulate the ABI. We will 50o 70o • Degrade high resolution data from the current polar orbiting satellites to GOES-R resolution in the gap region, including • HRPT from the NOAA satellites (for timeliness) • MODIS from Terra and Aqua • FRAC from Metop • Improve intercalibration between satellites, • Time-stamp each pixel. Animation: Example of winds from composite GEO/LEO satellite data over Antarctica.

6. Advantage to Funding this Year Why now? • High spatial and temporal resolution proxy data is available now, but may not be for long: • Terra and Aqua are both healthy at this time, although both are operating beyond their life expectancies. • We have access to real-time HRPT data from high latitude direct broadcast reception sites: Barrow, Tromsø, Sodankyla, McMurdo, Rothera, etc. However, due to their remote locations and our limited resources to maintain real-time access, the availability can not be guaranteed over the long term. • NWP centers have noted the deficiency and want the latitudinal gap filled soon, if possible. (L.-P. Riishojgaard, 2005, and International Winds Working Group acknowledgement).

7. Year 1 Budget and Year 2 Outlook Year 1: The budget covers the initial development of the composite wind product. Examples have already been generated, though additional, significant tasks are required: • accounting for inter-satellite calibration differences, • correcting for parallax in viewing the cloud tracers from different satellites and instruments, and • developing the logic for applying a common time-stamp to regions within the composite that correspond to the viewing by specified satellites. Budget for Year One: $69,800 Year 2: Upon the successful development and demonstration of the new blended product, we will have addressed a request by NWP centers to fill the remaining AMV gap and achieved a true global coverage. During Year 2, additional improvements will be addressed, as needed, and the impacts on numerical model forecasts will be evaluated in collaboration with NWP centers.