Infrared Spectral Imaging of Martian Clouds and Ices

David R. Klassen, James Bell, Robert R. Howell, Paul E. Johnson, William Golisch, Charles D. Kaminski, David Griep

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Multispectral images of Mars, taken at the NASA Infrared Telescope Facility (IRTF) near and at the 1995 opposition, are used to identify and track its atmospheric clouds and ground ices. Band depth mapping is used to help distinguish between the composition of volatiles and provide a check for the techniques of principal components analysis (PCA) and linear mixture modeling (LMM). PCA/LMM are used to create maps that track clouds and volatiles, a technique that requires no a priori spectral information in order to create these maps. Band depth maps at 3.33 μm, which have been shown to trace CO2frosts, show some transient features which could indicate polar CO2clouds at the time of these observations. We show that band depth maps at 2.25 μm are good tracers of H2O frosts and that band depth maps at 3.69 μm can distinguish between coarse- and fine-grained water frosts. These maps have allowed the detection of fine-grained water frosts in the north polar region and along the morning and evening limb regions. From the PCA technique we find that just two principal components can account for over 99% of the data variance. The first of these is an infrared albedo unit and the second is an ice/thermal unit. Plotting the spectral data cubes in this new vector space, we find that most of the martian disk can be modeled by spectrally mixing three endmember spectra having extreme values of these principal components. The morning and evening regions of Mars are composed of 40-60% of the north polar ice/thermal component endmember, indicating a frost component there consistent with the band depth mapping results. With a combination of these techniques it is possible to not only identify the extensive martian clouds, but to also determine composition. These new results are particularly relevant in light of recent Mars Pathfinder descent temperature profile data that indicated upper atmosphere temperatures below the CO2frost condensation point, implying that CO2ice clouds may be an important radiative component of the current martian climate.

Original languageEnglish (US)
Pages (from-to)36-48
Number of pages13
JournalIcarus
Volume138
Issue number1
DOIs
StatePublished - Mar 1 1999
Externally publishedYes

Fingerprint

ice
principal components analysis
principal component analysis
evening
morning
mars
Mars
Mars Pathfinder
infrared telescopes
frost
vector spaces
multispectral image
plotting
upper atmosphere
descent
polar region
limbs
albedo
temperature profile
temperature profiles

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Klassen, D. R., Bell, J., Howell, R. R., Johnson, P. E., Golisch, W., Kaminski, C. D., & Griep, D. (1999). Infrared Spectral Imaging of Martian Clouds and Ices. Icarus, 138(1), 36-48. https://doi.org/10.1006/icar.1998.6058

Infrared Spectral Imaging of Martian Clouds and Ices. / Klassen, David R.; Bell, James; Howell, Robert R.; Johnson, Paul E.; Golisch, William; Kaminski, Charles D.; Griep, David.

In: Icarus, Vol. 138, No. 1, 01.03.1999, p. 36-48.

Research output: Contribution to journalArticle

Klassen, DR, Bell, J, Howell, RR, Johnson, PE, Golisch, W, Kaminski, CD & Griep, D 1999, 'Infrared Spectral Imaging of Martian Clouds and Ices', Icarus, vol. 138, no. 1, pp. 36-48. https://doi.org/10.1006/icar.1998.6058
Klassen DR, Bell J, Howell RR, Johnson PE, Golisch W, Kaminski CD et al. Infrared Spectral Imaging of Martian Clouds and Ices. Icarus. 1999 Mar 1;138(1):36-48. https://doi.org/10.1006/icar.1998.6058
Klassen, David R. ; Bell, James ; Howell, Robert R. ; Johnson, Paul E. ; Golisch, William ; Kaminski, Charles D. ; Griep, David. / Infrared Spectral Imaging of Martian Clouds and Ices. In: Icarus. 1999 ; Vol. 138, No. 1. pp. 36-48.
@article{4523d99b3fa14df4bc85fb12e5018287,
title = "Infrared Spectral Imaging of Martian Clouds and Ices",
abstract = "Multispectral images of Mars, taken at the NASA Infrared Telescope Facility (IRTF) near and at the 1995 opposition, are used to identify and track its atmospheric clouds and ground ices. Band depth mapping is used to help distinguish between the composition of volatiles and provide a check for the techniques of principal components analysis (PCA) and linear mixture modeling (LMM). PCA/LMM are used to create maps that track clouds and volatiles, a technique that requires no a priori spectral information in order to create these maps. Band depth maps at 3.33 μm, which have been shown to trace CO2frosts, show some transient features which could indicate polar CO2clouds at the time of these observations. We show that band depth maps at 2.25 μm are good tracers of H2O frosts and that band depth maps at 3.69 μm can distinguish between coarse- and fine-grained water frosts. These maps have allowed the detection of fine-grained water frosts in the north polar region and along the morning and evening limb regions. From the PCA technique we find that just two principal components can account for over 99{\%} of the data variance. The first of these is an infrared albedo unit and the second is an ice/thermal unit. Plotting the spectral data cubes in this new vector space, we find that most of the martian disk can be modeled by spectrally mixing three endmember spectra having extreme values of these principal components. The morning and evening regions of Mars are composed of 40-60{\%} of the north polar ice/thermal component endmember, indicating a frost component there consistent with the band depth mapping results. With a combination of these techniques it is possible to not only identify the extensive martian clouds, but to also determine composition. These new results are particularly relevant in light of recent Mars Pathfinder descent temperature profile data that indicated upper atmosphere temperatures below the CO2frost condensation point, implying that CO2ice clouds may be an important radiative component of the current martian climate.",
author = "Klassen, {David R.} and James Bell and Howell, {Robert R.} and Johnson, {Paul E.} and William Golisch and Kaminski, {Charles D.} and David Griep",
year = "1999",
month = "3",
day = "1",
doi = "10.1006/icar.1998.6058",
language = "English (US)",
volume = "138",
pages = "36--48",
journal = "Icarus",
issn = "0019-1035",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Infrared Spectral Imaging of Martian Clouds and Ices

AU - Klassen, David R.

AU - Bell, James

AU - Howell, Robert R.

AU - Johnson, Paul E.

AU - Golisch, William

AU - Kaminski, Charles D.

AU - Griep, David

PY - 1999/3/1

Y1 - 1999/3/1

N2 - Multispectral images of Mars, taken at the NASA Infrared Telescope Facility (IRTF) near and at the 1995 opposition, are used to identify and track its atmospheric clouds and ground ices. Band depth mapping is used to help distinguish between the composition of volatiles and provide a check for the techniques of principal components analysis (PCA) and linear mixture modeling (LMM). PCA/LMM are used to create maps that track clouds and volatiles, a technique that requires no a priori spectral information in order to create these maps. Band depth maps at 3.33 μm, which have been shown to trace CO2frosts, show some transient features which could indicate polar CO2clouds at the time of these observations. We show that band depth maps at 2.25 μm are good tracers of H2O frosts and that band depth maps at 3.69 μm can distinguish between coarse- and fine-grained water frosts. These maps have allowed the detection of fine-grained water frosts in the north polar region and along the morning and evening limb regions. From the PCA technique we find that just two principal components can account for over 99% of the data variance. The first of these is an infrared albedo unit and the second is an ice/thermal unit. Plotting the spectral data cubes in this new vector space, we find that most of the martian disk can be modeled by spectrally mixing three endmember spectra having extreme values of these principal components. The morning and evening regions of Mars are composed of 40-60% of the north polar ice/thermal component endmember, indicating a frost component there consistent with the band depth mapping results. With a combination of these techniques it is possible to not only identify the extensive martian clouds, but to also determine composition. These new results are particularly relevant in light of recent Mars Pathfinder descent temperature profile data that indicated upper atmosphere temperatures below the CO2frost condensation point, implying that CO2ice clouds may be an important radiative component of the current martian climate.

AB - Multispectral images of Mars, taken at the NASA Infrared Telescope Facility (IRTF) near and at the 1995 opposition, are used to identify and track its atmospheric clouds and ground ices. Band depth mapping is used to help distinguish between the composition of volatiles and provide a check for the techniques of principal components analysis (PCA) and linear mixture modeling (LMM). PCA/LMM are used to create maps that track clouds and volatiles, a technique that requires no a priori spectral information in order to create these maps. Band depth maps at 3.33 μm, which have been shown to trace CO2frosts, show some transient features which could indicate polar CO2clouds at the time of these observations. We show that band depth maps at 2.25 μm are good tracers of H2O frosts and that band depth maps at 3.69 μm can distinguish between coarse- and fine-grained water frosts. These maps have allowed the detection of fine-grained water frosts in the north polar region and along the morning and evening limb regions. From the PCA technique we find that just two principal components can account for over 99% of the data variance. The first of these is an infrared albedo unit and the second is an ice/thermal unit. Plotting the spectral data cubes in this new vector space, we find that most of the martian disk can be modeled by spectrally mixing three endmember spectra having extreme values of these principal components. The morning and evening regions of Mars are composed of 40-60% of the north polar ice/thermal component endmember, indicating a frost component there consistent with the band depth mapping results. With a combination of these techniques it is possible to not only identify the extensive martian clouds, but to also determine composition. These new results are particularly relevant in light of recent Mars Pathfinder descent temperature profile data that indicated upper atmosphere temperatures below the CO2frost condensation point, implying that CO2ice clouds may be an important radiative component of the current martian climate.

UR - http://www.scopus.com/inward/record.url?scp=0001817712&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001817712&partnerID=8YFLogxK

U2 - 10.1006/icar.1998.6058

DO - 10.1006/icar.1998.6058

M3 - Article

VL - 138

SP - 36

EP - 48

JO - Icarus

JF - Icarus

SN - 0019-1035

IS - 1

ER -