MODIS Airborne Simulator (MAS)

Objective and Summary:

• Fly the ER-2 repeatedly over the surface site at Barrow (71°19.37'N, 156°34.9'W) and nearby open water and fast ice of the Chukchi Sea.
• Take-off was delayed one hour to allow the University of Washington CV-580 aircraft to test the IR engine-overheating indicator. Due to continued malfunction, the CV-580 never ended up coordinating any of the flight legs over Barrow on this flight.
• The ER-2 flew three parallel and repeating ground tracks of 294km in length that were parallel to the NOAA-14 ground track at 2240 UTC (heading of 320.31° at Barrow).
• The bulk of the flight tracks over the Chukchi Sea were cloudy, with uniform Arctic stratus present over land and nearby coastal fast ice, with scattered broken overlying altostratus and cirrus, with single layer cirrus on some occasions. Other coordinations included:

Coordinations:

• F-14 satellite (2032 UTC)
• NOAA-14 satellite (2240 UTC)

Key Flight Legs:

• The ER-2 flew a NW flight line from point 1 (70°22.5'N, 154°44'W) to point 2 (72°25'N, 160°W), then reversed course, overflying the ARM site each time (two passes). The aircraft then flew a parallel track displaced 40km to the West with two round trip flight legs, followed by another pair of flight legs displaced another 40km to the West. Each flight leg was 294km in length. The flight tracks were all parallel and on a heading of 320.31°/140.31°, corresponding to the orbital inclination of NOAA-14 as it overflew the ARM site at 2240 UTC.
• The AirMISR was turned on for 6 acquisitions: over the Barrow ARM site and neighboring flight legs West of Barrow, including acquisitions when the sun was in the orbital inclination of NOAA-14, and when the NOAA-14 and F-14 satellites passed over the area. The AirMISR operated at the following times:
  • 2025-2039 (Brooks Range enroute - scattered-clear sky)
  • 2100-2113 UTC (ARM - uniform stratus with scattered-broken AS)
  • 2126-2139 UTC (eastern line; ARM)
  • 2149-2202 UTC (central line)
  • 2219-2238 UTC (central line; stratus below at time of NOAA-14 overpass)
  • 2251-2307 UTC (western line)
  • 2329-2343 UTC (western line)
  • 0008-0022 (Brooks Range on return - thick cirrus)

Pilot Report:

• The ER-2 pilot reported multilayer stratus clouds over the ice near Barrow, with clear sky over the tundra. The Brooks Range had thin cirrus over it on the way out and thicker stratus with some underlying altostratus on the return to Fairbanks.

Meteorology:

• Winds decreased during the day to 16kts Easterly, with some snow and drizzle. The coastal stratus broke up in the early afternoon, leaving broken clouds at two levels (500 and 1500m). Some cirrus clouds were present over Barrow in the morning.

Instrument Status:

• AirMISR (Airborne Multi-angle Imaging Spectroradiometer): The 4^th, 5^th, 6^th runs collected all 9 look angles, while the other 4 early runs collected between 3 and 8 view angles; the last run over the Brooks Range failed to collect any data
• AMPR (Advanced Microwave Precipitation Radiometer): Worked well
• CLS (Cloud Lidar System): Worked well
• HIS (High-resolution Interferometer Sounder): Worked for take-off through first 2 flight legs over ARM site (flight lines 1 and 2) and then failed (1:42hr of mission)
• MAS (MODIS Airborne Simulator): Port 4 (8.3-14.0 µm) disconnected for nitrogen purge
• MIR (Millimeter-wave Imaging Radiometer): Worked well
• SSFR (Solar Spectral Flux Radiometer): Worked well