Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472390
J. Susskind
TOVS (TIROS Operational Vertical Sounder) is the operational temperature-moisture profile sounding system on the NOAA polar orbiting satellites, comprised of HIRS2, a 20 channel IR sounder, MSU, a 4 channel microwave sounder, and SSU a 3 channel IR pressure modulated stratospheric temperature sounder. The authors have analyzed data from NOAA 9 for Dec. 1985-Dec. 1986 and NOAA 10 for Dec. 1986-Dec. 1988 as part of the Pathfinder project. Products, produced twice daily, on a 1/spl deg//spl times/1/spl deg/ latitude-longitude grid, include land/ocean surface skin temperature, atmospheric temperature and humidity profile, total atmospheric O/sub 3/ column burden, cloud top height and amount, outgoing longwave radiation and longwave cloud radiative forcing, and precipitation estimate. A brief description of the methodology to analyze the data is given, stressing the need for simultaneous IR and microwave observations. Results showing interseasonal and interannual variability and the effects of El Nino are shown. Water vapor distribution is validated compared to radiosondes and shows considerable skill in the interannual variability sense. Cloud fields are validated indirectly by their use in the computation of OLR, which shows almost perfect agreement with the ERBE OLR product. Cloud fields are compared with those produced by ISCCP, and significant qualitative differences in cloud height distribution are shown. Perhaps the most important scientific finding is the very close positive relationship between the distribution of tropical upper tropospheric water vapor and precipitation in space and time.<>
{"title":"The TOVS Pathfinder Path A data set","authors":"J. Susskind","doi":"10.1109/COMEAS.1995.472390","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472390","url":null,"abstract":"TOVS (TIROS Operational Vertical Sounder) is the operational temperature-moisture profile sounding system on the NOAA polar orbiting satellites, comprised of HIRS2, a 20 channel IR sounder, MSU, a 4 channel microwave sounder, and SSU a 3 channel IR pressure modulated stratospheric temperature sounder. The authors have analyzed data from NOAA 9 for Dec. 1985-Dec. 1986 and NOAA 10 for Dec. 1986-Dec. 1988 as part of the Pathfinder project. Products, produced twice daily, on a 1/spl deg//spl times/1/spl deg/ latitude-longitude grid, include land/ocean surface skin temperature, atmospheric temperature and humidity profile, total atmospheric O/sub 3/ column burden, cloud top height and amount, outgoing longwave radiation and longwave cloud radiative forcing, and precipitation estimate. A brief description of the methodology to analyze the data is given, stressing the need for simultaneous IR and microwave observations. Results showing interseasonal and interannual variability and the effects of El Nino are shown. Water vapor distribution is validated compared to radiosondes and shows considerable skill in the interannual variability sense. Cloud fields are validated indirectly by their use in the computation of OLR, which shows almost perfect agreement with the ERBE OLR product. Cloud fields are compared with those produced by ISCCP, and significant qualitative differences in cloud height distribution are shown. Perhaps the most important scientific finding is the very close positive relationship between the distribution of tropical upper tropospheric water vapor and precipitation in space and time.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125436602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472357
P. R. Schwartz
Satellite remote sensing has been a powerful tool for increasing our understanding of ocean processes. Imaging radiometry, altimetry and radar have been used to measure and define surface processes. Some of this technology has transitioned to an operational role in support of ocean and weather forecasting and other maritime applications. Next generation sensors, particularly interferometric radar and high resolution spectral imaging promise to provide even better information to ocean scientists, Today, there is an increased interest in the coastal oceans. The US Navy's new maritime strategy of operations from the sea anywhere, anytime is driving application of remote sensing technologies to prepare this littoral battlespace. Coastal remote sensing presents peculiar challenges-requiring higher spatial and temporal resolution. But, with these challenges come new opportunities such as increased use of aircraft platforms and better synergism with in situ measurements.<>
{"title":"New directions in coastal and ocean remote sensing","authors":"P. R. Schwartz","doi":"10.1109/COMEAS.1995.472357","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472357","url":null,"abstract":"Satellite remote sensing has been a powerful tool for increasing our understanding of ocean processes. Imaging radiometry, altimetry and radar have been used to measure and define surface processes. Some of this technology has transitioned to an operational role in support of ocean and weather forecasting and other maritime applications. Next generation sensors, particularly interferometric radar and high resolution spectral imaging promise to provide even better information to ocean scientists, Today, there is an increased interest in the coastal oceans. The US Navy's new maritime strategy of operations from the sea anywhere, anytime is driving application of remote sensing technologies to prepare this littoral battlespace. Coastal remote sensing presents peculiar challenges-requiring higher spatial and temporal resolution. But, with these challenges come new opportunities such as increased use of aircraft platforms and better synergism with in situ measurements.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126769869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472322
S. Rajan, S. Mathur, C. R. Philbrick
An analysis of atmospheric water vapor profiles measured by a multiple wavelength Raman lidar system often shows a great deal of fine structure. In this paper the scales of this structure are examined with respect to both the temporal variability and the variation with respect to altitude. The authors have observed that the water vapor profiles exhibit structure on the order of the resolution of the lidar (75 m). Using two independent wavelengths this structure was verified. The study of temporal variations of water vapor on a fine scale are more difficult to quantify. In an effort to do this a model was created using minimum square error techniques and the deviations from this model are studied.<>
{"title":"Analysis of atmospheric water vapor measurements using a Raman lidar","authors":"S. Rajan, S. Mathur, C. R. Philbrick","doi":"10.1109/COMEAS.1995.472322","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472322","url":null,"abstract":"An analysis of atmospheric water vapor profiles measured by a multiple wavelength Raman lidar system often shows a great deal of fine structure. In this paper the scales of this structure are examined with respect to both the temporal variability and the variation with respect to altitude. The authors have observed that the water vapor profiles exhibit structure on the order of the resolution of the lidar (75 m). Using two independent wavelengths this structure was verified. The study of temporal variations of water vapor on a fine scale are more difficult to quantify. In an effort to do this a model was created using minimum square error techniques and the deviations from this model are studied.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129419620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472371
J. Turk, F. Marzano, M.A. Farrar, E. Smith
An upcoming NASA satellite platform, the Tropical Rainfall Measuring Mission (TRMM), represents the first opportunity to incorporate both multifrequency passive microwave and active radar measurements in its retrieval algorithms. The TRMM microwave imager (TMI) includes many of the same passive channels as the current Special Sensor Microwave Imager (SSMI), with the addition of a 10.7 GHz channel. The 14 GHz incoherent precipitation radar (PR) scans an across-track swath width about one-third the width of the forward-view conical TMI scan. Therefore, the radar data arrives about a minute after the TMI scan, and the PR and TMI beams view significantly different profiles in the atmosphere for a given on-Earth pixel location. During the 1992-1993 TOGA-COARE experiment in the western Pacific Ocean, a DC-8-based precipitation radar and an ER-a-based 4-channel microwave radiometer gathered data over a multitude of precipitating storm regions including the forming and mature stages of a tropical cyclone. Example imagery and vertical radar profiles are presented. These data are currently being used by the authors for vertical profiling algorithms which exploit the information contained in both the radar and radiometer. The radar data provide clues to the underlying cloud vertical structure that can be used to mitigate ambiguities in profile-based retrieval algorithms that rely upon the passive T/sub B/ alone.<>
{"title":"Measurements and implications for combined radar-passive microwave rainfall profiling techniques","authors":"J. Turk, F. Marzano, M.A. Farrar, E. Smith","doi":"10.1109/COMEAS.1995.472371","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472371","url":null,"abstract":"An upcoming NASA satellite platform, the Tropical Rainfall Measuring Mission (TRMM), represents the first opportunity to incorporate both multifrequency passive microwave and active radar measurements in its retrieval algorithms. The TRMM microwave imager (TMI) includes many of the same passive channels as the current Special Sensor Microwave Imager (SSMI), with the addition of a 10.7 GHz channel. The 14 GHz incoherent precipitation radar (PR) scans an across-track swath width about one-third the width of the forward-view conical TMI scan. Therefore, the radar data arrives about a minute after the TMI scan, and the PR and TMI beams view significantly different profiles in the atmosphere for a given on-Earth pixel location. During the 1992-1993 TOGA-COARE experiment in the western Pacific Ocean, a DC-8-based precipitation radar and an ER-a-based 4-channel microwave radiometer gathered data over a multitude of precipitating storm regions including the forming and mature stages of a tropical cyclone. Example imagery and vertical radar profiles are presented. These data are currently being used by the authors for vertical profiling algorithms which exploit the information contained in both the radar and radiometer. The radar data provide clues to the underlying cloud vertical structure that can be used to mitigate ambiguities in profile-based retrieval algorithms that rely upon the passive T/sub B/ alone.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123216412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472370
S.B. Moncet, R. Isaacs, J. Hegarty
A physical retrieval algorithm for the simultaneous retrieval of atmospheric temperature, water vapor and cloud liquid water as well as surface skin temperature and emissivity from microwave sensors has been developed by Moncet and Isaacs (1994, 1992). The algorithm uses a nonlinear inversion method similar to the one described by Rodgers (1976) for the inversion of the measured brightness temperatures. Climatology provides the desired inter-correlation between the various elements of the state vector. This information is used to effectively reduce the number of degrees of freedom in the problem, and therefore reduce the dependence of the solution on the first guess. Information from other sources, such as forecast models, is integrated by optimally combining it with the primary background information. Emissivity is treated by retrieving one emissivity value per sensor channel. The degree of correlation between the emissivities in each channel is specified through the first-guess error covariance matrix. This method offers more flexibility than the one proposed by Eyre (1990) and makes it possible to apply the algorithm to combinations of sensors with mixed viewing geometries and polarizations such as the DMSP microwave sensor suite. The algorithm has been tested based on simulated data and was successfully applied to limited sets of real measurements from the combined DMSP microwave sensors (SSM/T-1, T2 and SSM/I) over both ocean and land.<>
{"title":"Application of the unified retrieval approach to real DMSP sensor data over ocean and land","authors":"S.B. Moncet, R. Isaacs, J. Hegarty","doi":"10.1109/COMEAS.1995.472370","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472370","url":null,"abstract":"A physical retrieval algorithm for the simultaneous retrieval of atmospheric temperature, water vapor and cloud liquid water as well as surface skin temperature and emissivity from microwave sensors has been developed by Moncet and Isaacs (1994, 1992). The algorithm uses a nonlinear inversion method similar to the one described by Rodgers (1976) for the inversion of the measured brightness temperatures. Climatology provides the desired inter-correlation between the various elements of the state vector. This information is used to effectively reduce the number of degrees of freedom in the problem, and therefore reduce the dependence of the solution on the first guess. Information from other sources, such as forecast models, is integrated by optimally combining it with the primary background information. Emissivity is treated by retrieving one emissivity value per sensor channel. The degree of correlation between the emissivities in each channel is specified through the first-guess error covariance matrix. This method offers more flexibility than the one proposed by Eyre (1990) and makes it possible to apply the algorithm to combinations of sensors with mixed viewing geometries and polarizations such as the DMSP microwave sensor suite. The algorithm has been tested based on simulated data and was successfully applied to limited sets of real measurements from the combined DMSP microwave sensors (SSM/T-1, T2 and SSM/I) over both ocean and land.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126466789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472396
E. Kasischke, L. Bourgeau-Chavez, N. French
Wildfires play a central role in the ecology of boreal forests throughout the circumpolar region. Fires result in distinct and characteristic signatures on all remote sensing imagery. The large proportion of total area burned in boreal forests occurs in large fire events-the majority of area burned occurs in fires greater than 10,000 ha in size. These fires result in signatures which are not only spatially heterogeneous, but also have distinct temporal signatures. The authors present the results of a study which investigated the use of a variety of systems to monitor the effects of fire on remote sensing data collected over a large (40,000 ha) forest fire near Tok, Alaska. This fire occurred during the summer of 1991. Visible and near-IR region (AVHRR, SPOT) as well the microwave region (the ERS-1 and JERS-1 SARs) observations were made. The studies have shown that in the visible and near-IR data sets, the remotely-sensed signatures result from variations in the levels of burn intensity and patterns of vegetation regrowth. These patterns can clearly being interpreted through examination of vegetation indices derived from the AVHRR and SPOT data sets. On the other hand, the analyses of the microwave imagery collected by the ERS-1 SAR show that the spatial patterns of radar backscatter are primarily due to variations in surface roughness due to variations in burn intensity as well as variations in soil moisture, while the temporal patterns of radar backscatter are due to seasonal variations in soil moisture. The authors present examples of the remotely-sensed data sets along with ground-truth measurements which illustrate the sources of variations observed in the satellite imagery.<>
{"title":"Multi-sensor analysis of the effects of a wildfire in an Alaskan black spruce forest","authors":"E. Kasischke, L. Bourgeau-Chavez, N. French","doi":"10.1109/COMEAS.1995.472396","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472396","url":null,"abstract":"Wildfires play a central role in the ecology of boreal forests throughout the circumpolar region. Fires result in distinct and characteristic signatures on all remote sensing imagery. The large proportion of total area burned in boreal forests occurs in large fire events-the majority of area burned occurs in fires greater than 10,000 ha in size. These fires result in signatures which are not only spatially heterogeneous, but also have distinct temporal signatures. The authors present the results of a study which investigated the use of a variety of systems to monitor the effects of fire on remote sensing data collected over a large (40,000 ha) forest fire near Tok, Alaska. This fire occurred during the summer of 1991. Visible and near-IR region (AVHRR, SPOT) as well the microwave region (the ERS-1 and JERS-1 SARs) observations were made. The studies have shown that in the visible and near-IR data sets, the remotely-sensed signatures result from variations in the levels of burn intensity and patterns of vegetation regrowth. These patterns can clearly being interpreted through examination of vegetation indices derived from the AVHRR and SPOT data sets. On the other hand, the analyses of the microwave imagery collected by the ERS-1 SAR show that the spatial patterns of radar backscatter are primarily due to variations in surface roughness due to variations in burn intensity as well as variations in soil moisture, while the temporal patterns of radar backscatter are due to seasonal variations in soil moisture. The authors present examples of the remotely-sensed data sets along with ground-truth measurements which illustrate the sources of variations observed in the satellite imagery.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125756608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472359
S. Contu, F. Marinelli
M.I.M.R. is the acronym of a Multifrequency Imaging Microwave Radiometer i.e. an instrument whose scientific objectives are the monitoring of the Earth surface and its atmosphere. This monitoring is performed at 6 frequencies: 6.8, 10.65, 18.7, 23.6, 36.5 and 89 GHz. Alenia Spazio is responsible, as prime contractor, for the instrument and antenna system design with the related test activities. This paper describes the radiometer antenna system composed by 3 elements : an offset parabolic reflector named "main reflector" illuminated by a cluster of 9 feeds at the frequencies written above, a small offset parabolic reflector named "cold reflector" used for calibration purposes and pointed toward the cold space at 2.70 K, a box filled with absorbing material named "hot load" which simulates the black body behaviour to allow the instrument calibration at 3000 K.<>
{"title":"M.I.M.R.: a conical scanning antenna system for a multifrequency imaging microwave radiometer design, measurements and future developments","authors":"S. Contu, F. Marinelli","doi":"10.1109/COMEAS.1995.472359","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472359","url":null,"abstract":"M.I.M.R. is the acronym of a Multifrequency Imaging Microwave Radiometer i.e. an instrument whose scientific objectives are the monitoring of the Earth surface and its atmosphere. This monitoring is performed at 6 frequencies: 6.8, 10.65, 18.7, 23.6, 36.5 and 89 GHz. Alenia Spazio is responsible, as prime contractor, for the instrument and antenna system design with the related test activities. This paper describes the radiometer antenna system composed by 3 elements : an offset parabolic reflector named \"main reflector\" illuminated by a cluster of 9 feeds at the frequencies written above, a small offset parabolic reflector named \"cold reflector\" used for calibration purposes and pointed toward the cold space at 2.70 K, a box filled with absorbing material named \"hot load\" which simulates the black body behaviour to allow the instrument calibration at 3000 K.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"128 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133876230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472385
M. D. O'Brien, G. Evanisko, C. R. Philbrick
Clouds and aerosols play an important role in the radiative processes affecting the Earth's climate and the thermodynamic properties of the atmosphere. Therefore, it is crucial to gain greater insight into the structure and composition of clouds and aerosols. One approach to achieving this consists of employing several different remote sensing systems operating at multiple wavelengths. At Penn State, an interdisciplinary group of researchers following this approach has developed a new research tool called WAVE-LARS (Water Aerosol Vapor Experiment-Lidar And Radar Sounder). This instrument includes a volume scanning 94 GHz radar, a volume scattering multi-wavelength lidar, and a vertically pointing Rayleigh/Raman lidar. The 94 GHz radar was based on a previous radar constructed at Penn State, augment ed with new volume scanning and polarization capabilities. This system provides vertical profiles of atmospheric water vapor and temperature. The theory, design, and initial results from the volume scanning lidar is discussed.<>
{"title":"Initial results from a volume scanning three wavelength polarization lidar","authors":"M. D. O'Brien, G. Evanisko, C. R. Philbrick","doi":"10.1109/COMEAS.1995.472385","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472385","url":null,"abstract":"Clouds and aerosols play an important role in the radiative processes affecting the Earth's climate and the thermodynamic properties of the atmosphere. Therefore, it is crucial to gain greater insight into the structure and composition of clouds and aerosols. One approach to achieving this consists of employing several different remote sensing systems operating at multiple wavelengths. At Penn State, an interdisciplinary group of researchers following this approach has developed a new research tool called WAVE-LARS (Water Aerosol Vapor Experiment-Lidar And Radar Sounder). This instrument includes a volume scanning 94 GHz radar, a volume scattering multi-wavelength lidar, and a vertically pointing Rayleigh/Raman lidar. The 94 GHz radar was based on a previous radar constructed at Penn State, augment ed with new volume scanning and polarization capabilities. This system provides vertical profiles of atmospheric water vapor and temperature. The theory, design, and initial results from the volume scanning lidar is discussed.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134371277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472397
K. Ranson, J. Smith, G. Sun, J. Weishampel, R. Knox
One sided leaf area index (LAI) and above ground woody biomass are important parameters for describing the function and productivity of forested ecosystems. It is well known that remotely sensed reflected solar radiation can be related to the LAI of a vegetation canopy. Recently, studies have demonstrated that synthetic aperture radar (SAR) can be used to estimate above ground standing biomass. The authors describe the development of algorithms for using optical and microwave data to infer LAI and biomass by using a forest succession model to simulate forest canopy parameters for use with optical and microwave remote sensing models. Models for canopy reflectances and backscatter coefficients were used separately to develop relationships with LAI and biomass, respectively. The algorithms were applied to Airborne Visible-InfraRed Imaging Spectrometer (AVIRIS) and AirSAR images over a forested area in central Maine, USA. The resultant images ate evaluated and combined into a map related to potential ecosystem productivity.<>
{"title":"Forest structure from combined optical and microwave modeling and measurements","authors":"K. Ranson, J. Smith, G. Sun, J. Weishampel, R. Knox","doi":"10.1109/COMEAS.1995.472397","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472397","url":null,"abstract":"One sided leaf area index (LAI) and above ground woody biomass are important parameters for describing the function and productivity of forested ecosystems. It is well known that remotely sensed reflected solar radiation can be related to the LAI of a vegetation canopy. Recently, studies have demonstrated that synthetic aperture radar (SAR) can be used to estimate above ground standing biomass. The authors describe the development of algorithms for using optical and microwave data to infer LAI and biomass by using a forest succession model to simulate forest canopy parameters for use with optical and microwave remote sensing models. Models for canopy reflectances and backscatter coefficients were used separately to develop relationships with LAI and biomass, respectively. The algorithms were applied to Airborne Visible-InfraRed Imaging Spectrometer (AVIRIS) and AirSAR images over a forested area in central Maine, USA. The resultant images ate evaluated and combined into a map related to potential ecosystem productivity.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116864930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472379
D.G. Johnson, W. Traub, K. Chance, K. Jucks, R. Stachnik
Combined infrared and microwave remote sensing measurements of the stratosphere are combined to test several aspects of a constrained photochemical model. The authors find that a model with conventional chemistry only is unable to reproduce the observed abundance of ClO and HOCl relative to HCl, while results from a model which includes 10% production of HCl from the reaction of OH and ClO are in good agreement with the observations. The modified model predicts that the rates of production and loss of ozone are in balance at altitudes where the photochemical lifetimes are short compared to the characteristic transport time (30-40 km), in agreement with the rates calculated directly from the authors' measurements of HO/sub 2/, OH, NO/sub 2/, O/sub 3/, and ClO. The modified model also shows that for the balloon flight analyzed halogen-catalyzed ozone loss plays a lesser role than previously believed.<>
{"title":"Combined optical and microwave remote sensing measurements of the stratosphere from a balloon platform: improving our understanding of ozone photochemistry","authors":"D.G. Johnson, W. Traub, K. Chance, K. Jucks, R. Stachnik","doi":"10.1109/COMEAS.1995.472379","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472379","url":null,"abstract":"Combined infrared and microwave remote sensing measurements of the stratosphere are combined to test several aspects of a constrained photochemical model. The authors find that a model with conventional chemistry only is unable to reproduce the observed abundance of ClO and HOCl relative to HCl, while results from a model which includes 10% production of HCl from the reaction of OH and ClO are in good agreement with the observations. The modified model predicts that the rates of production and loss of ozone are in balance at altitudes where the photochemical lifetimes are short compared to the characteristic transport time (30-40 km), in agreement with the rates calculated directly from the authors' measurements of HO/sub 2/, OH, NO/sub 2/, O/sub 3/, and ClO. The modified model also shows that for the balloon flight analyzed halogen-catalyzed ozone loss plays a lesser role than previously believed.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"32 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132089673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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