SUCCESS 05/02/96 Mission Daily Schedule

The DC-8 and ER-2 flew a coordinated mission over Boulder, Co. to sample a wave-cloud and study the effects of the DC-8 exhaust and contrails on the wave-cloud. The DC-8 flew in and out of the wave-cloud while the ER-2 flew above. Measurements were coordinated with the NOAA-14 satellite overpass at 4 UTC.

Highlights

Wave Structure (96502)
In the following gif images, several fields are plotted versus distance along DC-8 flight tracks upwind of the wave-cloud. Plots are shown for each of the 4 legs aligned with the wind. The fields plotted are:

  • Potential temperature contours (vs. z and x) from MTP data (white) [B. Gary]
  • MMS DC-8 static air temperature (red) [R. Chan]
  • Laser hygrometer H2O mixing ratios (cyan) [G. Sachse]
  • relative humidity with respect to ice (RHI) (green)
  • CVI ice crystal number density (magenta) [Twohy, Gandrud]

The potential temperature surfaces slope upward/downward as the DC-8 flew into/out of the wave-cloud. The increase in RHI in the wave-crest is due to both the increase in H2O and the decrease in T. Updraft speeds estimated from the slope in theta surfaces and the wind speed range from 0.75 to 1.5 m/s. The peak CVI ice crystal number densities in wave-cloud penetrations (not shown) were 5-10/cc. Given the updraft speeds and temperatures, these number densities are consistent with theoretical calculations. Large peak supersaturations also occur at the leading edge of the cloud (20-50%).

All of the data shown here is preliminary. Refinements in calibrations are needed to improve accuracy.


Flight Reports

ER-2 Flight: 96110

Date: May 02, 1996

Mission Objectives

Observe the effect of DC-8 aircraft exhaust and contrails on wave clouds.

Flight Track

Flight Summary

Take-off time was 1630 UTC. ER-2 followed the DC-8 to SE Wyoming. No set patterns were flown. The ER-2 followed the DC-8 south again. The ER-2 flew several runs behind the DC-8. ER-2 pilot reported heavy turbulence at flight altitude. The ER-2 flew over contrails and was level in a run at a NOAA overpass at 2035 UTC.

Highlights

Runs for wave cloud near Boulder, CO.

Instrument Status

  • MODIS Airborne Simulator (MAS): Operated. Good data collected.
  • Cloud Aerosol Lidar System (CALS): Operated. Good data collected.
  • High-Resolution Interferometer Sounder (HIS): Operated up to 1935 UTC. Failed apparently due to shaking from turbulence and problems in reset procedure.
  • Millimeter-wave Imaging Radiometer(MIR): Operated. Good data collected.
  • Tilt Scan CCD Camera (TSCC): Operated up to 1910 UTC.
  • Radiation Measuring System (RAMS): Operated. Good data collected.
  • RC-10 Camera: Operated (black and white visible film- 6 inch lens).

Additional Pilot Notes: Highly turbulent flight.

Mission Summary

DC-8 SUCCESS flight #212 [960212] (scientist: Eric Jensen)

SUMMARY: The basic flight went well. After a few hours of searching, we found an ideal wave-cloud east over Boulder, Colorado, at about 39 K' (around -63 C). We flew about 2.5 patterns through the cloud. The vertical displacement in the wave appeared to be about 2000 ft. The vertical displacement was also evident in the MTP measurements. Measurements made near the leading edge should be very useful for understanding ice nucleation processes.

Mission Objective

  • sample wave-clouds over Medicine Bow, WY
  • deposit exhaust upwind of the clouds and let the ER-2 (which images the clouds from above) determine, if the exhaust has any impact on the clouds
  • sample the leading edge of the cloud to determine the ice nucleation activity spectrum

Flight Log

OPERATIONS
FLIGHT PLAN:
We will transit to Medicine Bow Wyoming (41 deg. 22 min., 106 deg. 19 min.) at 35 K' and determine whether wave-clouds are present. If the clouds are absent or too high to sample, we will fly to a range in northern Wyoming (44 deg. 22 min., 107 deg 10 min.) and fly along the range to look for wave-clouds.
Starting near the highest point in the wave-cloud, we will fly upwind, following potential temperature surfaces, through the leading edge of the cloud and upwind 15 min. Then we will turn and fly back up our exhaust trail back into the cloud. Next, we will turn 270 deg. and fly a 10 min. leg normal to the wind, along the leading edge of the cloud. Finally, we will execute a dog-leg turn and fly another 10 min. leg along the leading edge of the cloud, attempting to intersect our exhaust trail flowing into the cloud. This pattern should take about an hour.
We will repeat this pattern 3 times. After the first pattern, the ER-2 should arrive and fly a compact pattern above the leading edge of the cloud. No strict coordination with the ER-2 is required other than sending them the point on our track normal to the wind at the leading edge of the cloud.

TAKEOFF/LANDING
The DC-8 left Salina at 16.35 UTC (11.35 am local time) and returned to Salina at 22.45 UTC

FLIGHT REPORT
We proceeded to Medicine Bow at 35-37 K', but no wave-clouds were apparent. Extensive cirrus were visible at lower altitudes. Next, we shifted the pattern to the southeast (41.48 deg, 105.58 deg), but again, no waveclouds were nearby. We were nearly ready to give up when wave-clouds were spotted to the south. We extended our N-S (cross-wind) leg about 50 miles south to get in to the clouds.
We flew the designated pattern twice. On the first pattern, we stayed at 39 K'. On the second pattern, we descended to 37 K' at the beginning of the upwind leg. This descent appeared to maintain constant potential temperature. When we penetrated the leading edge the second time, we ascended to 41 K'. We appeared to be skimming the cloud-top at this altitude.
At the end of the second pattern, we turned back south along the leading edge and then flew east downwind through the cloud at 39 K'. We maintained constant altitude for 15 min. downwind of the cloud, and then headed home.

METEOROLOGY-REPORT
OBSERVATIONS: As expected, tropopause was low and warm: near 10 km and -50 C. Popcorn cumulous was present at about 3-5 K'.

INSTRUMENT STATUS
All instruments are functioning.

  • BALLENTHIN: No problems
  • BAUMGARDNER: No problems
  • BRUNE: No problems
  • CHAN: No problems
  • COGGIOLA: No problems
  • COOPER: No problems with CN, IN worked better.
  • DADS: No problems
  • FERRY: No problems
  • GARY: No problems
  • GERBER: No problems
  • HAGEN: No problems
  • HALLET: No problems
  • HEYMSFIELD: Potential problem with recording cryogenic hygrometer data.
  • HUDSON: No problems
  • LAWSON: Periods of false triggers.
  • RODGERS: No problems
  • SACHSE: No problems
  • TALBOT: No problems
  • TWOHY: No problems
  • UTHE: No problems
  • VALERO: No problems
  • WEINHEIMER: No problems

Mission Highlights

  • large oscillations in the tropopause height associated with the mountain waves
  • very small crystals in wave-clouds (5-20 microns).

96/05/02 CART site activity

Meteorology at the Central Facility

Weather Conditions from Site Operators Log

 

Visiting Instruments at Central Facilities

 

 

CART Instrument Operations at Central Facilities

Key: O = operational, X = down or degraded

  • RASS, 50 MHz, (hourly): O
  • RASS, 915 MHz, (hourly): O
  • BSRN: O
  • SIROS: O
  • SMOS, (24 hrs): O
  • SWATS (24 hrs): O
  • EBBR, (24 hrs): O
  • WSI, (every 10 min.) X
  • MWR, (24 hrs): O
  • IRT: X
  • MPL, (24 hrs): O
  • BLC, (24 hrs): O
  • AERI, (24 hrs): O
  • SORTI, (daytime, sunny): O
  • Raman Lidar (daytime): X
  • 60M Temperature and Humidity: O
  • 25M Temperature and Humidity: O
  • 25M IRT: O
  • 25M MultiFilter Radiometer: O
  • 25M Upwelling IR: O
  • 25M Upwelling Solar: O
  • 10M IRT: O
  • 10M MultiFilter Radiometer: O
  • Aerosol System: X
  • Radiosondes, (Every 3 hrs, from 1:30 UTC): O

 

CART Instrument Operations at Boundary Facilities

There are four staffed Boundary Facilities, each having Balloon Borne Sounding Systems (BBSS) and MicroWave Radiometers (MWR). During the IOP period, sondes are launched every three hours round the clock, starting at 5:30 GMT (12:30 CST). The sites are listed below. Times listed following a site indicate questionable data or failed sonde launches. Weather conditions are recorded in the Boundary Facilities Site Operator's Log.

  • Hillsboro, KS (BF-1): Okay
  • Vici, OK (BF-4): Okay
  • Morris, OK (BF-5): Okay
  • Purcell, OK (BF-6): Okay

 

CART Instrumentation at Extended Facilities

There are numerous unstaffed Extended Facilities. The specific instrumentation at the extended facilities varies from site to site, but generally includes a flux station (either an Energy Balance Bowen Ration (EBBR) system or an Eddy Correlation (ECOR) system), a Solar and InfraRed Observing System (SIROS), and a Standard Meteorology Observing Station (SMOS). For the locations of the Extended Facilities, and their suite of instrumentation, see the table and map of the Extended CART site. The comments below indicate specific data streams with identified problems.

  • Problem at Extended Facility:
  • E2: SIROS
  • E7: SMOS, EBBR, SIROS
  • E9: EBBR
  • E10: ECOR, SIROS
  • E16: ECOR
  • E20: SMOS, EBBR, SIROS
  • E24: SIROS

 

Key Comments/Observations related to flights

Mixture of cirrus and contrails, non-flight day.