TY - JOUR
T1 - Feasibility of retrieving dust properties and total column water vapor from solar spectra measured using a lander camera on mars
AU - Manago, Naohiro
AU - Noguchi, Katsuyuki
AU - Hashimoto, George L.
AU - Senshu, Hiroki
AU - Otobe, Naohito
AU - Suzuki, Makoto
AU - Kuze, Hiroaki
N1 - Funding Information:
This work was supported by the joint research program of CEReS, Chiba university (2015, 2016).
Publisher Copyright:
© The Author(s). 2017.
PY - 2017
Y1 - 2017
N2 - Dust and water vapor are important constituents in the Martian atmosphere, exerting significant influence on the heat balance of the atmosphere and surface. We have developed a method to retrieve optical and physical properties of Martian dust from spectral intensities of direct and scattered solar radiation to be measured using a multi-wavelength environmental camera onboard a Mars lander. Martian dust is assumed to be composed of silicate-like substrate and hematite-like inclusion, having spheroidal shape with a monomodal gamma size distribution. Error analysis based on simulated data reveals that appropriate combinations of three bands centered at 450, 550, and 675 nm wavelengths and 4 scattering angles of 3°, 10°, 50°, and 120° lead to good retrieval of four dust parameters, namely, aerosol optical depth, effective radius and variance of size distribution, and volume mixing ratio of hematite. Retrieval error increases when some of the observational parameters such as color ratio or aureole are omitted from the retrieval. Also, the capability of retrieving total column water vapor is examined through observations of direct and scattered solar radiation intensities at 925, 935, and 972 nm. The simulation and error analysis presented here will be useful for designing an environmental camera that can elucidate the dust and water vapor properties in a future Mars lander mission.
AB - Dust and water vapor are important constituents in the Martian atmosphere, exerting significant influence on the heat balance of the atmosphere and surface. We have developed a method to retrieve optical and physical properties of Martian dust from spectral intensities of direct and scattered solar radiation to be measured using a multi-wavelength environmental camera onboard a Mars lander. Martian dust is assumed to be composed of silicate-like substrate and hematite-like inclusion, having spheroidal shape with a monomodal gamma size distribution. Error analysis based on simulated data reveals that appropriate combinations of three bands centered at 450, 550, and 675 nm wavelengths and 4 scattering angles of 3°, 10°, 50°, and 120° lead to good retrieval of four dust parameters, namely, aerosol optical depth, effective radius and variance of size distribution, and volume mixing ratio of hematite. Retrieval error increases when some of the observational parameters such as color ratio or aureole are omitted from the retrieval. Also, the capability of retrieving total column water vapor is examined through observations of direct and scattered solar radiation intensities at 925, 935, and 972 nm. The simulation and error analysis presented here will be useful for designing an environmental camera that can elucidate the dust and water vapor properties in a future Mars lander mission.
KW - Direct solar radiation
KW - Dust particles
KW - Inverse analysis
KW - Mars atmosphere
KW - Radiative transfer simulation
KW - Scattered solar radiation
KW - Total column water vapor
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U2 - 10.1186/s40645-017-0131-z
DO - 10.1186/s40645-017-0131-z
M3 - Article
AN - SCOPUS:85064317926
VL - 4
JO - Progress in Earth and Planetary Science
JF - Progress in Earth and Planetary Science
SN - 2197-4284
IS - 1
M1 - 16
ER -