ER-2 Sortie 98-073
Friday, June 2, 1998
Steve Platnick: Flight Scientist
Objectives:Overfly the ARM site in coordination with University of Washington CV-580 aircraft for remote sensing validation and cloud masking. Continue northward without the CV-580 to fly several legs over the SHEBA ice camp (76°48N, 167°31W). The leg from the ARM site to the ice camp was flown in coordination with a NOAA-14 overpass. Return flight leg was over the ARM site.
Takeoff 1940 UTC
Landing 0230 UTC (June 3)
The ER-2 flew three flight legs of about 260 km in length, oriented with the solar azimuth (about 164° at mean time of overpasses), while the CV-580 attempted above and below-cloud bidirectional reflectance measurements and in situ profiles through the cloud.
After overflying the ARM site, the ER-2 flew a NW flight line coordinated with NOAA-14 (318° heading). Because of a slightly earlier than scheduled takeoff, the pilot had to make two circular turns en route to the start of the SHEBA legs to match the timing of the satellite overpass.
At the SHEBA ice station, the ER-2 made two-and-one-half north-south legs of about 260 km in length. Because of a late turn-on for AirMISR during the southbound leg over the ice station (point 6 to point 4), the pilot turned back to repeat the start of the leg (at point 6).
The ER-2 overflew the ARM site on the return to Ft. Wainwright.
The AirMISR was turned on for 6 acquisitions: three times over the ARM site, twice over SHEBA ice station, and once on the return over the ARM site. The AirMISR operated at the following times with notes of observed clouds as seen by the instrument:
Pilot report: The ER-2 pilot reported cloud cover just north of Barrow during the flight legs over the ARM site, with clear sky to the south. Some cirrus was seen en route to SHEBA. The ice station was at the northern end of an extensive solid cloud sheet with clear sky just to the north. Barrow was clear on the return leg.
Multilevel clouds, including cirrus, were expected throughout the region.
SHEBA: Morning report of fog and clouds at all levels, including cirrus. Morning radar reported clouds from 3.1-3.8 km; surface winds southeasterly at 5 kts. Near the time of the ER-2 overpass (2100 UTC) the ice station radar reported multiple cloud layers between 0.3-1.5 km and 1.5-3.7 km; lidar reported liquid stratocumulus at 3.5 km; surface observations were clear to the NE, solid cover to the south, clearer to the west, surface winds from the northeast at 5 kts.
Barrow: Cloud conditions were expected to be similar to those at the ice station. The CV-580 flew coordinated patterns over the ARM site and reported a broken stratocumulus layer.
AirMISR Airborne Multi-angle Imaging Spectroradiometer
AMPR Advanced Microwave Precipitation Radiometer
CLS Cloud Lidar System
HIS High-resolution Interferometer Sounder
MAS MODIS Airborne Simulator
MIR Millimeter-wave Imaging Radiometer
SSFR Solar Spectral Flux Radiometer