Arctic Weather Every 10 Minutes: Design & Operation of ABI for PCW

Transcription

1 Arctic Weather Every 10 Minutes: Design and Operation of ABI for PCW Dr. Paul C. Griffith and Sue Wirth 31st Space Symposium, Technical Track, Colorado Springs, Colorado This document is not subject to the controls of the International Traffic in Arms Regulations (ITAR) or the Export Administration Regulations (EAR). The Advanced Baseline Imager (ABI) is a NOAA funded, NASA administered meteorological instrument program. This document does not reflect the views or policy of the GOES R Program Office.

2 Need for More Accurate Arctic Weather Prediction is Growing Dramatically Decreasing ice leading to increasing need for more accurate weather predictions More frequent and intense Arctic cyclones More weather and environmental uncertainty Increased commercial shipping, operations, and permanent residents Geostationary satellites cannot provide adequate spatial resolution LEO satellites cannot provide adequate temporal resolution Arctic weather models hampered by aging pixels for initial conditions Cannot dwell on evolving weather events Aging LEO constellations leading to fewer arctic observations Credit: United States Navy Solution: ABI on PCW provides Arctic weather data every 10 minutes 2

3 Maximize Quality and Quantity of Data Products at Minimum Risk and Cost Fundamental trade space for mission design Success achieved through mission level optimization Rather than optimizing payload, satellite, or ground processing Key parameters for obtaining quality data products: Spatial resolution Coverage area and repetition interval Spectral bands SNR Radiometric accuracy Derived mission parameter: Orbit Systems engineering: Obtaining optimum balance of requirements 3

4 HEO vs. LEO Balances Resolution Against Coverage LEO: Low altitude provides good resolution Limited instantaneous coverage Poor temporal resolution (4 to 6 hours to form complete image) Cannot dwell on evolving weather events HEO: Resolution supports weather models Provides full view of Arctic Provides excellent temporal resolution (10 minute images) Provides ability to dwell on evolving weather events Requires two imagers for 100% coverage 4

5 ABI Resolution in HEO Supports Weather Models Distortion corrections required for VIIRS Edge of VIIRS Swath Edge of Full Disk U.S. National Weather Service (NWS) uses 3 km grids Environment Canada, European Centre for Medium Range Weather Forecasts (ECMWF), and United Kingdom Meteorological Office all use 2.5 km UK model has regional analysis 1.5 km grid for severe storms Both ABI/PCW and VIIRS are compatible with all requirements 5

6 Choice of Specific HEO Orbit Balances Resolution and Lifetime GEO Molniya TAP Tundra Perigee (km) 35, ,100 23,144 Apogee (km) 35,786 39,819 43,500 48,442 Apogee/GEO 100% 111% 122% 135% Period (hours) Radiation Moderate Severe Severe ~GEO ABI Lifetime 15 years 5 years 7 years 15 years Tundra GEO-sized Tundra resolution acceptable Only 20% greater than Molniya TAP Molniya Tundra provides significant lifetime improvement (3x Molniya) Mission optimization: Tundra is best Significantly lower 15 year life cycle cost while still meeting needs Added benefit of significant Antarctica coverage 6

7 GSD for HEO ABI at Apogee Better than GSD for CONUS from GEO ABI GSD (km) GEO CONUS Latitude (degrees) Arctic GEO ABI: 1 km GSD = 1.5 center of CONUS HEO ABI: 1 km GSD = 1.35 center of Arctic at apogee HEO 7

8 PCW Objective: 100% Coverage Above 65 N Latitude Coverage means images at least every 20 minutes Goal is at least every 15 minutes Desire is to be comparable to next generation geostationary imagers (i.e. every 10 minutes) Plus regional observations Collected in addition to Full Disk image, not instead of it Used to monitor rapidly evolving weather events Current LEO imagers only provide Arctic images every 4 to 6 hours Would require dozens of satellites to meet PCW coverage requirements Based on RFI released by Public Works and Government Services Canada in November

9 HEO PCW Provides Arctic Same Weather Data Coverage as Geostationary Imagers Imagers Exelis EUMETSAT MTG PCW Coverage 100% 95% 90% 9

10 PCW Provides 24 Hour Coverage of Arctic New Full Disk Images Every 10 Min Longitude Telesat Tundra Orbit Notional Equator Crossings LONG 1(LAT 0) LONG 2(LAT 0) Satellite Satellite H o u r s / D a y Minimum coverage > 4 hours everywhere on Earth 20 elevation Picture courtesy of Telesat 10

11 Two Satellites Provide 100% Arctic Coverage Video courtesy of Telesat 11

12 Coverage Near Equator is Function of Ascending Nodes Latitude Longitude Ascending nodes of 67 W and 113 E maximizes coverage of Indian Ocean (Meteosat 7 scheduled to be retired in 2016) 4 12

13 Orbital Snapshots Demonstrate HEO ABI Timeline s Autonomous Operations Apogee hours Timeline repeats automatically Meso collection automatically adjusted for orbital motion Swaths overlapped to ensure no gaps Earth rotation Orbital motion Spacecraft yaw Minimal ground station commanding 13

14 ABI Class Imager Designed for Spectral Flexibility to Meet Customer Needs FPM VNIR MWIR LWIR Resolution Center wavelength (µm) FPA (km) ABI AHI AMI PCW A A A A A A A A A A A A A A A A PCW channels listed are one possible combination; RFI provided 21 candidates ABI provides all 12 PCW priority 1 bands Plus four priority 2 bands Meets all resolution requirements Meets most goal resolutions Color Key: Not in ABI Different FPA 14

15 PCW Bands Provide Data for Weather, Ice, Fire, Volcanic Ash, etc. Band Data Products 0.47 Blue: Surface, clouds, aerosols 0.51 Green: daytime green for true color 0.64 Red: Wind, clouds, ice mapping 0.87 Wind, aerosols, vegetation 1.05 Snow grain and clouds 1.38 Cirrus detection 1.61 Snow cloud distinction, ice cover 2.25 Aerosol, smoke, cloud phase 3.9 Fog, fire detection, ice/cloud separation, wind 6.19 Wind, high level humidity 6.95 Wind, mid level humidity 7.34 Wind, low level humidity 8.5 Total water, cloud phase 9.61 Total ozone 10.4 Cloud, surface, cirrus 11.2 Cloud, SST, ash 12.3 Ash, SST 13.3 Cloud height Sources: PWGSC PCW RFI 1Nov2013 ABI Formulation Phase study 15

16 First ABI Class Imager Operating in Orbit on Himawari 8 (TRL 9) True color composite (Band 1 (blue), Band 2 (green), Band 3 (red)) from Japan Meteorological Agency website eng/satellite/news/himawari89/ _himawari8_first_images.html 16

17 Conclusion: Mission Level Optimization Maximizes Products & Minimizes Life Cycle Cost Tundra orbit provides optimum balance for PCW Sufficient resolution Significantly lower life cycle cost ABI operational flexibility is ideally suited to PCW mission Rapid Full Disk coverage Interleaved regional observations Autonomous operation Sixteen spectral bands include all PCW priority 1 channels Resolution meets all requirements and most goals Only next generation geostationary imager currently operating in orbit 17 Four of seven ABI class imagers have been delivered