The Radiative Effects of Martian Water Ice Clouds on the Local Atmospheric Temperature Profile

Although atmospheric CO2 is a trace gas, it has seasonal variations and has increased over the last decade. Its seasonal variation and increase have substantial radiative effects on hyperspectral infrared (IR) radiance calculations in both longwave (LW) and shortwave (SW) CO2 absorption spectral regions that are widely used for weather and climate applications. The effects depend on the spectral coverage and spectral resolution. The radiative effect caused by the increase of CO2 has been calculated to be greater than 0.5 K within 5 years, whereas a radiative effect of 0.1–0.5 K is introduced by the seasonal variation in some CO2 absorption spectral regions. It is important to take into account the increasing trend and seasonal variation of CO2 in retrieving the atmospheric temperature profile from hyperspectral IR radiances and in the radiance assimilation in numerical weather prediction (NWP) models. The simulation further indicates that it is very difficult to separate atmospheric temperature and CO2 information from hyperspectral IR sounder radiances because the atmospheric temperature signal is much stronger than that of CO2 in the CO2 absorption IR spectral regions.

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Advances in atmospheric temperature profile measurements using high spectral resolution lidar

EPJ Web of Conferences ◽

10.1051/epjconf/201817601023 ◽

2018 ◽

Vol 176 ◽

pp. 01023

Author(s):

Ilya I. Razenkov ◽

Edwin W. Eloranta

Keyword(s):

Temperature Profile ◽

Spectral Resolution ◽

Atmospheric Temperature ◽

High Spectral Resolution ◽

Absolute Calibration ◽

Temperature Sensitive ◽

Backscatter Coefficient ◽

Rayleigh Backscattering ◽

Atmospheric Temperature Profile ◽

High Spectral Resolution Lidar

This paper reports the atmospheric temperature profile measurements using a University of Wisconsin-Madison High Spectral Resolution Lidar (HSRL) and describes improvements in the instrument performance. HSRL discriminates between Mie and Rayleigh backscattering [1]. Thermal motion of molecules broadens the spectrum of the transmitted laser light due to Doppler effect. The HSRL exploits this property to allow the absolute calibration of the lidar and measurements of the aerosol volume backscatter coefficient. Two iodine absorption filters with different line widths are used to resolve temperature sensitive changes in Rayleigh backscattering for atmospheric temperature profile measurements.

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Atmospheric temperature profile retrieval using multivariate nonlinear regression

IGARSS'97. 1997 IEEE International Geoscience and Remote Sensing Symposium Proceedings. Remote Sensing - A Scientific Vision for Sustainable Development ◽

10.1109/igarss.1997.615798 ◽

2002 ◽

Author(s):

J.-G. Miao ◽

K. Zhao ◽

G. Heygster

Keyword(s):

Temperature Profile ◽

Nonlinear Regression ◽

Atmospheric Temperature ◽

Multivariate Nonlinear Regression ◽

Atmospheric Temperature Profile

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Direct measurements of the effect of biomass burning over the Amazon on the atmospheric temperature profile

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-8211-2009 ◽

2009 ◽

Vol 9 (21) ◽

pp. 8211-8221 ◽

Cited By ~ 32

Author(s):

A. Davidi ◽

I. Koren ◽

L. Remer

Keyword(s):

Temperature Profile ◽

Amazon Basin ◽

Radiation Energy ◽

Atmospheric Temperature ◽

Lower Atmosphere ◽

Aerosol Layer ◽

Aerosol Absorption ◽

A Value ◽

Direct Measurements ◽

Atmospheric Temperature Profile

Abstract. Aerosols suspended in the atmosphere interact with solar radiation and clouds, thus change the radiation energy fluxes in the atmospheric column. In this paper we measure changes in the atmospheric temperature profile as a function of the smoke loading and the cloudiness, over the Amazon basin, during the dry seasons (August and September) of 2005–2008. We show that as the aerosol optical depth (AOD) increases from 0.02 to a value of ~0.6, there is a decrease of ~4°C at 1000 hPa, and an increase of ~1.5°C at 850 hPa. The warming of the aerosol layer at 850 hPa is likely due to aerosol absorption when the particles are exposed to direct illumination by the sun. The large values of cooling in the lower layers could be explained by a combination of aerosol extinction of the solar flux in the layers aloft together with an aerosol-induced increase of cloud cover which shade the lower atmosphere. We estimate that the increase in cloud fraction due to aerosol contributes about half of the observed cooling in the lower layers.

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