WMOD00269 - Laserfiche WebLink

Home Browse Search

PCASP number conc cm PCASP number concentration (calculated) - PCASP -3 PCASP volume conc PCASP volume concentration (calculated) - PCASP m cm 3-3 PCASP effective diameter PCASP effective diameter (calculated) - PCASP m PCASP MVD PCASP Mean Volume Diameter (calculated) - PCASP m CCN number conc cm Cloud Condensation Nuclei number concentration (calculated) - CCN -3 Actual SS % Cloud Condensation Nuclei actual supersaturation (calculated) – CCN *PCASP = Passive Cavity Aerosol Spectrometer Probe Table 3: List of data fields and their corresponding description 3.2 Instrumentation issues and data quality The timing of the funding was very instrumental in determining the success of the research effort. Since a new Texas based research aircraft was being instrumented as part of the WDMP grant, a hierarchy of tasks had to be accomplished before a level of readiness was accomplished for research flights to get underway. The tasks were the following: 1. Place an order for the cloud physics instrumentation (standard delivery time is 90 days). 2. Modify the aircraft to accommodate the cloud physics instrumentation. 3. Take delivery of the instrumentation. 4. Conduct ground tests to check instrumentation operation. 5. Conduct flight tests to check that all the instruments operate in flight conditions. Due to delays in issuing the Invitation for Bids for the identification of the aircraft to be leased, steps 1 to 5 (above) were all delayed to the extent that the research aircraft was instrumented in early August. Since the project focused around the measurement of deep convective clouds, the project was jeopardized from the outset since convective activity in the southern plains starts to decline in October. Therefore, there was no time left for thorough checks of the operation of the instrumentation under various flight conditions. All the instrumentation (except for the PCASP) was delivered and installed on the aircraft by thth the 4 August 2004. The aircraft departed the mechanic shop were it was being modified on 5 August. th On the 7 August the aircraft was flown to Lubbock TX where the PCASP aerosol instrument was picked up at the FedEx location and installed on the aircraft. The first research flight was conducted on the th afternoon of the 7 August 2004 when convective storms developed just to the north of the Lubbock area. thst 34 research flights were flown totaling 75 flight hours from the period 7 August 2004 to 1 October 2004. It was determined that extending the measurement program into October was not desirable due to the remarked climatological decline in convective activity in Texas, southeastern New Mexico and Oklahoma. Although most of the instrumentation was operational for the duration of the SPECTRA 1 project period, there were case days when the research mission was compromised due to malfunction or improper operation of the instruments. Most of these instrumentation issues were due to problems that originated from the manufacturer. There were no problems that originated from the negligence or oversight of the crew. Despite of the instrumentation deficiencies that are identified and listed in this report, an extensive amount of good quality research grade data was collected during the SPECTRA 1 field campaign that satisfy the objectives of the field program. During the SPECTRA 1 campaign, 34 research flights were flown totaling 75 flight hours. Out of the 34 flights, 7 flights had faulty CCN data, 8 flights had erroneous position data and 12 flights had erroneous Cloud Droplet Probe (CDP) data. Most of these instrumentation issues were due to problems that originated from the manufacturer. One should also take into consideration that this aircraft was a new platform and it was put to work immediately after the instrumentation was built and the aircraft modifications were complete. The Droplet Measurement Technologies (DMT) CCN counter was serial number 8, so this instrument was new in the cloud physics field. After the instrument was delivered and installed, the CCN data was 23