1. 1 The Imager/Sounder Paradigm Revisited Third GOES-R Users Conference Broomfield, Colorado May 11 th, 2004 Joe Criscione, Jim Bremer, and Donald Chu Swales Aerospace

2. 2 Joe Criscione 301-286-0070 Outline Examine Benefits of GEO Use GEO’s Assets as Paradigm Flow Instrument Architecture to Distributed Architecture Assess Impact to Requirements –Order of magnitude increase in Severe/Weather Mesoscale Sounding –Order of magnitude increase in Coastal Waters Imaging –Sacrifices CO 2 spectral resolution in Full Disk Sounding Examine Feasibility and a Concept of Operations

3. 3 Joe Criscione 301-286-0070 How to Exploit GEO High temporal sampling of Full-Disk –ABI images full disk every 5 minutes –All images from same point of view –Excellent way to observe change/flux Intense sampling of Region-of-Interest –Can observe any point at any time –Ideal for observing rare/important events Coastal Waters, Severe Weather, Natural and Man-Made Disasters

4. 4 Joe Criscione 301-286-0070 Use GEO’s Assets as Paradigm Current Architecture Imager (ABI) –2D products –Full disk/CONUS/Mesoscale Sounder (HES) –3D products (and coastal waters) –Full disk/CONUS/Mesoscale Proposed Architecture Full-Disk (ABI+) –2D and 3D products –Full Disk Region-of-Interest (HES+/-) –2D and 3D products –CONUS/Mesoscale Flow Instrument Architecture To Spacecraft Distributed Architecture Full-Disk S/C –Points at Nadir –ABI+ Scans Full Disk –Carries other payloads that require a Nadir deck (GRB, GLM, etc. ) Region-of-Interest S/C –Satellite points at target and HES+/- Collects data WITHOUT SCANNING Scanner dominates radiometric and pointing error budgets Reduces Field of Regard by order of magnitude Can double aperture for HES+/-

5. 5 Joe Criscione 301-286-0070 What’s Changed? Imager (ABI) Sounder (HES) 30cm Aperture 2-axis Scanner 30cm Aperture 2-axis Scanner Nadir Pointing Bus Nadir Pointing Bus Full-Disk Imaging 5 min revisit 0.5 km VIS 2.0 km IR 300:1 SNR 0.1K NEDT 16 channels Mesoscale Sounding 4 min meso 1 hr CONUS 4km GSD 64% DOEE 1.0 cm-1 0.1K NEDT Full-Disk Sounding 1 hr revisit 10km GSD 90% DOEE 1.0 cm-1 0.1K NEDT Coastal Waters 3 hr revisit 250m GSD 300:1 SNR Proposed Architecture Full-Disk (ABI+) Region-Of-Interest (HES+/-) 30cm Aperture 2-axis Scanner Nadir Pointing Bus Full-Disk Imaging 5 min revisit 0.5 km VIS 2.0 km IR 300:1 SNR 0.1K NEDT 16 channels NEDT: Noise Equivalent Delta Temperature GSD: Ground Sample Distance DOEE: Detector/Optics Ensquared Energy cm-1: Spectral Channel Width in wavenumber Flow Instrument Architecture to S/C Architecture Eliminate Scanner & Double Aperture 60 cm Aperture No Scanner Target Pointing Bus Current Architecture Full-Disk Sounding 5 min revisit 10km GSD 90% DOEE 3 cm -1 H 2 O 10 cm -1 CO 2 0.5K NEDT Could do 4km GSD at expense of NEDT & DOEE Concurrently with Imaging (NOT time shared) Move Full-Disk Sounding to ABI Trade Spectral Resolution and NEDT for Revisit Time in Full-Disk Sounding Mesoscale Sounding 4 min meso 1 hr CONUS 4km GSD 90% DOEE 1.0 cm-1 0.05K NEDT 2km GSD possible Coastal Waters 1 hr revisit 75m GSD 1000:1 SNR Order of Magnitude Improvement in Coastal Waters Order of Magnitude Improvement in Mesoscale Sounding

6. 6 Joe Criscione 301-286-0070 Serendipity CO 2 spectral resolution is hard –Narrow absorption feature –Best measured in Longwave where detectors are high cost/risk H 2 O spectral resolution is easy (comparatively) –Detector technology is mature –Lots of redundancy in the spectrum The atmosphere is cooperating for once –H 2 O fluctuates rapidly, but it is easy to observe –Temperature is hard to observe, but it is relatively stable Finesse it –Accurately measure H 2 O often and everywhere –Accurately measure temperature only in the CONUS/mesoscale regions

7. 7 Joe Criscione 301-286-0070 Feasibility Adding ~100 H 2 O channels to ABI+ –Data rate increase not overwhelming 100 at 10km = 1 at 1km –Continuous variable filter on top of 2D array Same front end as current ABI concept Adds one filter and one detector array 6-8 micron region has mature detector technology Can tolerate noise and missing channels Linear Variable Filter Optical Coating Laboratory Inc.http://www.ocli.com/pdf_files/products/lvf_faqs.pdf

8. 8 Joe Criscione 301-286-0070 Feasibility (cont’d) 60 cm aperture for HES+/- –SEVIRI has 50 cm aperture Spinning Enhanced Visible and Infrared Imager Flying on MSG right now Has a single axis scanner Weighs 260 kg (HES mass budget is 280 kg) Spacecraft pointing –Civilian high resolution LEO satellites point at targets with a 16,000 mph ground track GEO has a ground track of 0 mph –Can use same bus for both satellites Solar array can tilt 15 degrees off-normal with little effect on power GOES-N bus could slew from nadir to edge of earth in ~2 minutes Could raster scan CONUS with very little time wasted in slews –Need to examine method for downlinking science data

9. 9 Joe Criscione 301-286-0070 Concept of Operations ABI+ –Uses Kalman filter to track atmospheric state Can use LEO observations to initialize Kalman filter Tracking atmospheric state instead of retrieving state Distribute atmospheric state hourly on 10km grid –Potential for other products Can observe winds at varying altitudes Can distribute standard deviation of retrievals with hourly state –Identifies targets for HES+/- HES+/- –Raster scans CONUS when there are no Regions-Of-Interest Can interleave Regions-Of-Interest with CONUS scans –Has high resolution land bands as well as fire channel –Can re-initialize parts of full disk that fall out of convergence for the ABI+ Kalman filter (no need to wait for LEO pass) ABI+, HES+/-, and NPOESS work as integrated system

10. 10 Joe Criscione 301-286-0070 Conclusion Full-Disk/Region-Of- Interest Partitioning –Sacrifices spectral resolution of full disk soundings –No impact to full disk imaging products –Order of magnitude improvement to severe weather/mesoscale soundings –Order of magnitude improvement to coastal waters Same cost and risk –Achieves gains by optimizing spacecraft/instrument system –Balances full disk sounding needs and instrument complexity 250m GSD 75m GSD