Information content analysis of aerosol remote-sensing experiments using singular function theory 1: Extinction measurements

Abstract. Determination of aerosol optical properties with orbital passive remote sensing is a difficult task, as observations often have limited information. Multi-angle instruments, such as the Multi-angle Imaging SpectroRadiometer (MISR) and the POlarization and Directionality of the Earth's Reflectances (POLDER), seek to address this by making information-rich multi-angle observations that can be used to better retrieve aerosol optical properties. The paradigm for such instruments is that each angle view is made from one platform, with, for example, a gimballed sensor or multiple fixed view angle sensors. This restricts the observing geometry to a plane within the scene bidirectional reflectance distribution function (BRDF) observed at the top of the atmosphere (TOA). New technological developments, however, support sensors on small satellites flying in formation, which could be a beneficial alternative. Such sensors may have only one viewing direction each, but the agility of small satellites allows one to control this direction and change it over time. When such agile satellites are flown in formation and their sensors pointed to the same location at approximately the same time, they could sample a distributed set of geometries within the scene BRDF. In other words, observations from multiple satellites can take a variety of view zenith and azimuth angles and are not restricted to one azimuth plane as is the case with a single multi-angle instrument. It is not known, however, whether this is as potentially capable as a multi-angle platform for the purposes of aerosol remote sensing. Using a systems engineering tool coupled with an information content analysis technique, we investigate the feasibility of such an approach for the remote sensing of aerosols. These tools test the mean results of all geometries encountered in an orbit. We find that small satellites in formation are equally capable as multi-angle platforms for aerosol remote sensing, as long as their calibration accuracies and measurement uncertainties are equivalent. As long as the viewing geometries are dispersed throughout the BRDF, it appears the quantity of view angles determines the information content of the observations, not the specific observation geometry. Given the smoothly varying nature of BRDF's observed at the TOA, this is reasonable and supports the viability of aerosol remote sensing with small satellites flying in formation. The incremental improvement in information content that we found with number of view angles also supports the concept of a resilient mission comprised of multiple satellites that are continuously replaced as they age or fail.

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Improving Remote Sensing of Aerosol Microphysical Properties by Near-Infrared Polarimetric Measurements Over Vegetated Land: Information Content Analysis

Journal of Geophysical Research Atmospheres ◽

10.1002/2017jd027388 ◽

2018 ◽

Vol 123 (4) ◽

pp. 2215-2243 ◽

Cited By ~ 11

Author(s):

Weizhen Hou ◽

Zhengqiang Li ◽

Jun Wang ◽

Xiaoguang Xu ◽

Philippe Goloub ◽

...

Keyword(s):

Remote Sensing ◽

Content Analysis ◽

Information Content ◽

Near Infrared ◽

Microphysical Properties

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An algorithm for hyperspectral remote sensing of aerosols: 2. Information content analysis for aerosol parameters and principal components of surface spectra

Journal of Quantitative Spectroscopy and Radiative Transfer ◽

10.1016/j.jqsrt.2017.01.041 ◽

2017 ◽

Vol 192 ◽

pp. 14-29 ◽

Cited By ~ 19

Author(s):

Weizhen Hou ◽

Jun Wang ◽

Xiaoguang Xu ◽

Jeffrey S. Reid

Keyword(s):

Remote Sensing ◽

Content Analysis ◽

Information Content ◽

Principal Components ◽

Hyperspectral Remote Sensing ◽

Aerosol Parameters

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Remote sensing of aerosols with small satellites in formation flight

10.5194/amt-2017-473 ◽

2018 ◽

Author(s):

Kirk Knobelspiesse ◽

Sreeja Nag

Keyword(s):

Remote Sensing ◽

Optical Properties ◽

Information Content ◽

Systems Engineering ◽

Limited Information ◽

Aerosol Optical Properties ◽

Small Satellites ◽

Analysis Technique ◽

Technological Developments ◽

Aerosol Remote Sensing

Abstract. Determination of aerosol optical properties with orbital passive remote sensing is a difficult task, as observations often have limited information. Multi-angle instruments, such as the Multi-angle Imaging SpectroRadiometer (MISR) and the POlarization and Directionality of the Earth's Reflectances (POLDER), seek to address this by making information rich multi-angle observations, which can be used to better retrieve aerosol optical properties. The paradigm for such instruments is that each angle view is made from one platform, with, for example, a gimbaled sensor or multiple fixed view angle sensors. This restricts the observing geometry to a plane within the scene Bidirectional Reflectance Distribution Function (BRDF) observed at the top of the atmosphere (TOA). New technological developments, however, support sensors on small satellites flying in formation, which could be a beneficial alternative. Such sensors may have only one viewing direction each, but the agility of small satellites allows one to control this direction and change it over time. When such agile satellites are flown in formation and their sensors pointed to the same location at approximately the same time, they could sample a distributed set of geometries within the scene BRDF. In other words, observations from multiple satellites can take a variety view zenith and azimuth angles, and are not restricted to one azimuth plane as is the case with a single multi-angle instrument. It is not known, however, if this is as potentially capable as a multi-angle platform for the purposes of aerosol remote sensing. Using a systems engineering tool coupled with an information content analysis technique, we investigate the feasibility of such an approach for the remote sensing of aerosols. These tools test the mean results of all geometries encountered in an orbit. We find that small satellites in formation are equally capable as multi-angle platforms for aerosol remote sensing, as long as their calibration accuracies and measurement uncertainties are equivalent. As long as the viewing geometries are dispersed throughout the BRDF, it appears the quantity of view angles determines the information content of the observations, not the specific observation geometry. Given the smoothly varying nature of BRDF's observed at the TOA, this is reasonable, and supports the viability of aerosol remote sensing with small satellites flying in formation. The incremental improvement in information content that we found with number of view angles also supports the concept of a resilient mission comprised of multiple satellites that are continuously replaced as they age or fail.

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IMAGE OF THE REPUBLIC OF MORDOVIA IN THE MEDIA VOLGA FEDERAL DISTRICT (BASED ON CONTENT ANALYSIS OF NEWS PUBLICATIONS)

Sociopolitical sciences ◽

10.33693/2223-0092-2020-10-4-44-52 ◽

2020 ◽

Vol 10 (4) ◽

pp. 44-52

Author(s):

LARISA ZAITSEVA ◽

Keyword(s):

Content Analysis ◽

Information Content ◽

Federal District ◽

Information Space ◽

Political News ◽

Social Sphere ◽

The Media ◽

The Republic ◽

Number Of Publications

The territorial image is formed both purposefully by the subjects of image-making, and spontaneously-based on the influence of information content published in various media. The purpose of the research is to analyze the image of the Republic of Mordovia in the information space of the Volga Federal district. The image of the territory formed by external target audiences by means of news materials is studied using the method of case study and content analysis of publications: “Volga news”, “Federal Press” news of the PFD, “Pravda PFD”. The authors conclude that modern reality is perceived through the prism of the information field created by mass media. The media creates images filled with certain data, facts, colored by emotions, on the basis of which representations, opinions, judgments, and assessments are subsequently formed. The media play a significant role in shaping the territorial image, especially for external target audiences who are not familiar with the region and do not have their own assessment knowledge and experience. Most of the information content about the Republic in the studied media is related to the main thematic blocks: politics, economy, social sphere, culture (art, sports). Moreover, if in the publications “Volga news” and “Pravda PFD” mention of the region prevails in the economic block, then in the publications “Federal Press” and “Nezavisimaya Gazeta” - in the political one. The Volga news publication significantly dominates the rest in terms of the number of publications about Mordovia. The content of publications is mostly positive and neutral related to the issues of economic development of the territory and the preparation and holding of the world football championship. Pravda PFD mentions the Republic in the context of news from neighboring territories, most of the publications date back to 2018, but here the context is related to the Republic's positions among the regions of the PFD in various ratings. The publication “Federal-Press” forms a generally reflective image of the territory, focusing on the negative aspects of regional life. “Nezavisimaya Gazeta”, giving priority to political news, maintains a neutral and reflective context of publications, paying attention to the key problems of the territory. Thus, the desired image of the region is counter-dictated to the image broadcast by the media through various information channels, so it is necessary to constantly monitor the information space and timely correction of the broadcast materials.

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