Reflectivity of Mars at 1064 nm: Derivation from Mars Orbiter Laser Altimeter Data and Application to Climatology and Meteorol
Nicholas G. Heavens
(Submitted on 31 May 2016)
The Mars Orbiter Laser Altimeter (MOLA) on board Mars Global Surveyor (MGS) made ?108 measurements of the reflectivity of Mars at 1064 nm (R1064) by both active sounding and passive radiometry. Past studies of R1064 neglected the effects of atmospheric opacity and viewing geometry on both active and passive measurements and also identified a potential calibration issue with passive radiometry. Therefore, as yet, there exists no acceptable reference R1064 to derive a column opacity product from surface returns during active sounding for the purposes of atmospheric studies. Here, such a reference R1064 is derived by seeking RM,N1064: a Minnaert-corrected normal albedo under clear conditions and assuming minimal phase angle dependence. Over darker surfaces, RM,N1064 and the absolute level of atmospheric opacity were estimated from active sounding. Over all surfaces, the opacity derived from active sounding were used to filter out the cloudiest passive radiometry measurements and estimate RM,N1064. These estimates then were re-calibrated by comparison with RM,N derived from Hubble Space Telescope (HST) observations over areas of approximately uniform reflectivity. Estimates of RM,N1064 from both active sounding and re-calibrated passive radiometry mostly agree with HST observations. The resulting RM,N1064 is then used to derive and quantify the uncertainties of a column opacity product, which can be applied to meteorological and climatological studies of Mars, particularly to detect and measure mesoscale cloud/aerosol structures.
Comments: 49 pages, 23 figures, submitted to Icarus
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:1606.00035 [astro-ph.EP]
(or arXiv:1606.00035v1 [astro-ph.EP] for this version)
Submission history
From: Nicholas Heavens
[v1] Tue, 31 May 2016 20:37:47 GMT (9533kb,D)
http://arxiv.org/abs/1606.00035
