AIRCRAFT MEASUREMENTS AND ANALYSES OF CO, CH4, N2O
AND H2O(v) IN SUPPORT OF TRACE-P

 

Glen W. Sachse (NASA LaRC), Karen B. Bartlett (Univ. of New Hampshire), James Podolske (NASA ARC), and Nikita S. Pougatchev (Christopher Newport Univ.)  



    We will provide accurate, high precision measurements of carbon monoxide (CO), methane (CH4), nitrous oxide (N2O) and water vapor (H2O(v)) aboard the NASA DC-8 aircraft; and CO and CH4 aboard the NASA P-3B aircraft during the TRACE-P mission. These measurements will be made by fast response tunable diode laser sensors---the DACOM (Diferential Absorption CO Measurement) instrument for CO, CH4, and N2O on the DC-8, the DACOM II instrument for CO and CH4 on the P-3, and the DLH (Diode Laser Hygrometer) for H2O(v) on the DC-8.

    One objective of the our analyses will be to synthesize the high vertical resolution, aircraft CO and CH4 data from the DACOM instruments with MOPITT (Measurement Of Pollution In The Troposphere) CO profile and CH4 total column data for the purpose improving the quantitative interpretation of the MOPITT data. The ability of MOPITT to observe large regions of the Asian outflow within a single orbital pass over a long duration of time (prior to and after TRACE-P) combined with the added value of interpretation of the satellite data will greatly improve the prospect of quantifying the emissions outflow from Asia, the primary goal of TRACE-P. Integrating the MOPITT data into our analyses will be facilitated by Dr. Pougatchev, co-I with this proposal and PI for MOPITT Validation by Ground-based IR Solar Spectroscopy, and by Dr. J. Drummond, PI for MOPITT who has agreed to assist us as a cooperating scientist.

    Other objectives include: (a) investigation of the vertical and geographical distribution of these gas species in context with other data available in this region [e.g., PEM-West A and B missions, data from NOAA CMDL surface sites such as  Shemya, the Tae-Ahn Peninsula, Midway Island, and Guam, and MAPS (Measurement of Air Pollution from a Satellite) data]; (b) providing highly time-correlated, high precision data enabling the identification of possible source regions of sampled air parcels as well as the calculation of emission indices for a number of trace gases;  (c) providing fast response (10 Hz) water vapor data for studying atmospheric turbulence and fine structure; and (d) providing high accuracy data for input into atmospheric photochemical models.