GNDAOD

Two-Column Aerosol Project (TCAP): Ground based AOD measurements

20 May 2012 - 30 July 2012

Lead Scientist: Phil Russell

Observatory: AAF, PVC

To anchor aerosol optical depth (AOD) retrievals of the new instrument 4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research) flying in the Two Column Aerosol Project (TCAP), we will operate an ARM Cimel sun/sky photometer at Barnstable Municipal Airport, Cape Cod, MA. The ARM Cimel, with wavelength channels 0.34-1.6 microns, will first be calibrated during the 4STAR pre-mission calibration at Mauna Loa Observatory (MLO), Hawaii, 25 May -3 June 2012. It will then be used to measure AOD spectra at Barnstable Municipal Airport, Cape Cod, MA, 7-30 July 2012, where the G-1 aircraft will be based for TCAP. The resulting AOD values will be compared to those measured by 4STAR on the G-1 before takeoff and/or after landing. These comparisons will be used to anchor and/or calibrate the AOD measurements made by 4STAR on the G-1. RELEVANCY TO ARM: The proposed measurements will greatly increase confidence in aerosol measurements by the new instrument 4STAR in TCAP. 4STAR's measurements are a key element supporting the TCAP goal to reduce modeling uncertainty associated with the numerical treatment of aerosol transformation and cloud-aerosol interactions in large-scale models.