Description
We present highlights from recent ARM Cimel Sunphotometer (CSPHOT) deployments and previews of current and future field campaigns. As part of the Boundary Layer Cloud System, the CSPHOTs have recently been deployed at GOAMAZON(Brazil), and AWARE (Antarctica) and are being prepared for upcoming deployments at MICRE, LASIC, and DACCIWA field campaigns.
There are several updates on existing and new data products related to the CSPHOT. One example is a new product for Cloud Optical Depth. Since about 2010, a 2-channel algorithm for cloud optical depth, developed by Christine Chiu, has been used routinely by NASA AERONET (AErosol RObotic NETwork). However, there were limitations that the algorithm could be used only at vegetated sites. Using the 1640 nm channel in addition to the 870 nm and 440 nm channels allows retrievals over other surfaces as well (Chiu et al., 2012). A new ARM operational data product is being developed to apply this algorithm for all ARM sites, including the ARM AWARE Antarctic site.
Initial look at the zenith radiances, e.g. for 2016 Jan. at McMurdo, looks promising because there were long periods of persistent cloud cover. That of course means that the direct Sun aerosol optical depth observations are spotty. They will be analyzed in the context of previous antarctic sunphotometer observations summarized in Tomasi et al. (2015).
References:
http://www.arm.gov/instruments/csphot
Chiu, J. C., Marshak, A., Huang, C.-H., Várnai, T., Hogan, R. J., Giles, D. M., Holben, B. N., O’Connor, E. J., Knyazikhin, Y., and Wiscombe, W. J.: Cloud droplet size and liquid water path retrievals from zenith radiance measurements: examples from the Atmospheric Radiation Measurement Program and the Aerosol Robotic Network, Atmos. Chem. Phys., 12, 10313–10329, doi:10.5194/acp-12-10313-2012, 2012.
C. Tomasi, A.A. Kokhanovsky, A. Lupi, C. Ritter, A. Smirnov, N.T. O'Neill, R.S. Stone, B.N. Holben, S. Nyeki, C. Wehrli, A. Stohl, M. Mazzola, C. Lanconelli, V. Vitale, K. Stebel, V. Aaltonen, G. de Leeuw, E. Rodriguez, A.B. Herber, V.F. Radionov, T. Zielinski, T. Petelski, S.M. Sakerin, D.M. Kabanov, Y. Xue, L. Mei, L. Istomina, R. Wagener, B. McArthur, P.S. Sobolewski, R. Kivi, Y. Courcoux, P. Larouche, S. Broccardo, S.J. Piketh, Aerosol remote sensing in polar regions, Earth-Science Reviews, Volume 140, January 2015, Pages 108-157, ISSN 0012-8252, http://dx.doi.org/10.1016/j.earscirev.2014.11.001.
(http://www.sciencedirect.com/science/article/pii/S00128252
