The Experts below are selected from a list of 195 Experts worldwide ranked by ideXlab platform
A H Strahler - One of the best experts on this subject based on the ideXlab platform.
-
retrieval of red spectral albedo and bidirectional reflectance using avhrr hrpt and GOES Satellite observations of the new england region
Journal of Geophysical Research, 1999Co-Authors: Robert P Dentremont, Crystal B Schaaf, Wolfgang Lucht, A H StrahlerAbstract:As a prototyping exercise for the moderate-resolution imaging spectroradiometer (MODIS) albedo/BRDF product, we demonstrate the retrieval of bidirectional reflectance distribution functions (BRDFs) and red spectral albedo measures for the New England region, United States, from merged AVHRR and GOES radiances at a 1 km2 (nominal) spatial scale. These data were acquired during a 25-day period in early fall 1995. The spatial pattern of BRDF retrievals shows that urban, suburban, and interurban regions exhibit directional scattering that is well modeled by the geometric optics of shadow casting. The directional reflectance of more continuous forest areas is better described by volume-scattering mechanisms. Spectral albedos are larger in urban and suburban areas than in forested regions, as might be expected from the strong absorption of leaves in the red wave band. The red spectral albedo generally increases with solar zenith angle, as has been noted in ground measurements of broadband albedo. A number of technical limitations discussed constrain the absolute accuracy of retrieved albedos presented here, although the spatial patterns of albedo and the consistency of the BRDF shapes inspire confidence. These limitations will largely be overcome with application of our algorithm to data from the MODIS and MISR instruments on the EOS AM-1 platform.
Carl R Thornber - One of the best experts on this subject based on the ideXlab platform.
-
automated high temporal resolution thermal analysis of kilauea volcano hawai i using GOES Satellite data
International Journal of Remote Sensing, 2001Co-Authors: Andrew J L Harris, Eric Pilger, Luke P Flynn, Harold Garbeil, Peter J Mouginismark, James P Kauahikaua, Carl R ThornberAbstract:Thermal data are directly available from the Geostationary Operational Environmental Satellites (GOES) every 15 minutes at existing or inexpensively installed receiving stations. This data stream is ideal for monitoring high temperature features such as active lava flows and fires. To provide a near-real-time hot spot monitoring tool, we have developed, tested and installed software to analyse GOES data on-reception and then make results available in a timely fashion via the web. Our software automatically: (1) produces hot spot images and movies; (2) uses a thresholding procedure to generate a hot spot map; (3) updates hot spot radiance and cloud index time series; and (4) issues a threshold-based e-mail alert. Results are added to http://volcano1.pgd.hawaii.edu/GOES/ within ∼12 minutes of image acquisition and are updated every 15 minutes. Analysis of GOES data acquired for effusive activity at Kilauea volcano (Hawai'i) during 1997-98 show that short (<1 hour long) events producing 100m long (102 to 103...
-
complex effusive events at kīlauea as documented by the GOES Satellite and remote video cameras
Bulletin of Volcanology, 1999Co-Authors: Andrew J L Harris, Carl R ThornberAbstract:GOES provides thermal data for all of the Hawaiian volcanoes once every 15 min. We show how volcanic radiance time series produced from this data stream can be used as a simple measure of effusive activity. Two types of radiance trends in these time series can be used to monitor effusive activity: (a) Gradual variations in radiance reveal steady flow-field extension and tube development. (b) Discrete spikes correlate with short bursts of activity, such as lava fountaining or lava-lake overflows. We are confident that any effusive event covering more than 10,000 m2 of ground in less than 60 min will be unambiguously detectable using this approach. We demonstrate this capability using GOES, video camera and ground-based observational data for the current eruption of Kīlauea volcano (Hawai'i). A GOES radiance time series was constructed from 3987 images between 19 June and 12 August 1997. This time series displayed 24 radiance spikes elevated more than two standard deviations above the mean; 19 of these are correlated with video-recorded short-burst effusive events. Less ambiguous events are interpreted, assessed and related to specific volcanic events by simultaneous use of permanently recording video camera data and ground-observer reports. The GOES radiance time series are automatically processed on data reception and made available in near-real-time, so such time series can contribute to three main monitoring functions: (a) automatically alerting major effusive events; (b) event confirmation and assessment; and (c) establishing effusive event chronology.
-
chronology of the episode 54 eruption at kilauea volcano hawaii from GOES 9 Satellite data
Geophysical Research Letters, 1997Co-Authors: Andrew J L Harris, Luke P Flynn, Peter J Mouginismark, James P Kauahikaua, Carl R Thornber, Laszlo P Keszthelyi, David R Sherrod, Frank A Trusdell, Michael W Sawyer, Pierre FlamentAbstract:The free availability of GOES Satellite data every 15 minutes makes these data an attractive tool for studying short-term changes on cloud-free volcanoes in the Pacific basin. We use cloud-free GOES-9 data to investigate the chronology of the January 1997, episode 54 eruption of Kilauea Volcano, Hawaii. Seventy-six images for this effusive eruption were collected over a 60-hour period and show the opening and shutdown of active fissures, the draining and refilling of the Pu‘u ‘O‘o lava lake, and the cessation of activity at the ocean entry.
Robert P Dentremont - One of the best experts on this subject based on the ideXlab platform.
-
retrieval of red spectral albedo and bidirectional reflectance using avhrr hrpt and GOES Satellite observations of the new england region
Journal of Geophysical Research, 1999Co-Authors: Robert P Dentremont, Crystal B Schaaf, Wolfgang Lucht, A H StrahlerAbstract:As a prototyping exercise for the moderate-resolution imaging spectroradiometer (MODIS) albedo/BRDF product, we demonstrate the retrieval of bidirectional reflectance distribution functions (BRDFs) and red spectral albedo measures for the New England region, United States, from merged AVHRR and GOES radiances at a 1 km2 (nominal) spatial scale. These data were acquired during a 25-day period in early fall 1995. The spatial pattern of BRDF retrievals shows that urban, suburban, and interurban regions exhibit directional scattering that is well modeled by the geometric optics of shadow casting. The directional reflectance of more continuous forest areas is better described by volume-scattering mechanisms. Spectral albedos are larger in urban and suburban areas than in forested regions, as might be expected from the strong absorption of leaves in the red wave band. The red spectral albedo generally increases with solar zenith angle, as has been noted in ground measurements of broadband albedo. A number of technical limitations discussed constrain the absolute accuracy of retrieved albedos presented here, although the spatial patterns of albedo and the consistency of the BRDF shapes inspire confidence. These limitations will largely be overcome with application of our algorithm to data from the MODIS and MISR instruments on the EOS AM-1 platform.
Andrew J L Harris - One of the best experts on this subject based on the ideXlab platform.
-
automated high temporal resolution thermal analysis of kilauea volcano hawai i using GOES Satellite data
International Journal of Remote Sensing, 2001Co-Authors: Andrew J L Harris, Eric Pilger, Luke P Flynn, Harold Garbeil, Peter J Mouginismark, James P Kauahikaua, Carl R ThornberAbstract:Thermal data are directly available from the Geostationary Operational Environmental Satellites (GOES) every 15 minutes at existing or inexpensively installed receiving stations. This data stream is ideal for monitoring high temperature features such as active lava flows and fires. To provide a near-real-time hot spot monitoring tool, we have developed, tested and installed software to analyse GOES data on-reception and then make results available in a timely fashion via the web. Our software automatically: (1) produces hot spot images and movies; (2) uses a thresholding procedure to generate a hot spot map; (3) updates hot spot radiance and cloud index time series; and (4) issues a threshold-based e-mail alert. Results are added to http://volcano1.pgd.hawaii.edu/GOES/ within ∼12 minutes of image acquisition and are updated every 15 minutes. Analysis of GOES data acquired for effusive activity at Kilauea volcano (Hawai'i) during 1997-98 show that short (<1 hour long) events producing 100m long (102 to 103...
-
complex effusive events at kīlauea as documented by the GOES Satellite and remote video cameras
Bulletin of Volcanology, 1999Co-Authors: Andrew J L Harris, Carl R ThornberAbstract:GOES provides thermal data for all of the Hawaiian volcanoes once every 15 min. We show how volcanic radiance time series produced from this data stream can be used as a simple measure of effusive activity. Two types of radiance trends in these time series can be used to monitor effusive activity: (a) Gradual variations in radiance reveal steady flow-field extension and tube development. (b) Discrete spikes correlate with short bursts of activity, such as lava fountaining or lava-lake overflows. We are confident that any effusive event covering more than 10,000 m2 of ground in less than 60 min will be unambiguously detectable using this approach. We demonstrate this capability using GOES, video camera and ground-based observational data for the current eruption of Kīlauea volcano (Hawai'i). A GOES radiance time series was constructed from 3987 images between 19 June and 12 August 1997. This time series displayed 24 radiance spikes elevated more than two standard deviations above the mean; 19 of these are correlated with video-recorded short-burst effusive events. Less ambiguous events are interpreted, assessed and related to specific volcanic events by simultaneous use of permanently recording video camera data and ground-observer reports. The GOES radiance time series are automatically processed on data reception and made available in near-real-time, so such time series can contribute to three main monitoring functions: (a) automatically alerting major effusive events; (b) event confirmation and assessment; and (c) establishing effusive event chronology.
-
chronology of the episode 54 eruption at kilauea volcano hawaii from GOES 9 Satellite data
Geophysical Research Letters, 1997Co-Authors: Andrew J L Harris, Luke P Flynn, Peter J Mouginismark, James P Kauahikaua, Carl R Thornber, Laszlo P Keszthelyi, David R Sherrod, Frank A Trusdell, Michael W Sawyer, Pierre FlamentAbstract:The free availability of GOES Satellite data every 15 minutes makes these data an attractive tool for studying short-term changes on cloud-free volcanoes in the Pacific basin. We use cloud-free GOES-9 data to investigate the chronology of the January 1997, episode 54 eruption of Kilauea Volcano, Hawaii. Seventy-six images for this effusive eruption were collected over a 60-hour period and show the opening and shutdown of active fissures, the draining and refilling of the Pu‘u ‘O‘o lava lake, and the cessation of activity at the ocean entry.
Andrew K. Heidinger - One of the best experts on this subject based on the ideXlab platform.
-
A Physics Based GOES Satellite Product for Use in NREL’s National Solar Radiation Database
2014Co-Authors: Manajit Sengupta, Aron Habte, Peter Gotseff, A. Weekley, Anthony Lopez, C. Molling, Andrew K. HeidingerAbstract:The National Renewable Energy Laboratory (NREL), University of Wisconsin, and National Oceanic Atmospheric Administration are collaborating to investigate the integration of the Satellite Algorithm for Shortwave Radiation Budget (SASRAB) products into future versions of NREL's 4-km by 4-km gridded National Solar Radiation Database (NSRDB). This paper describes a method to select an improved clear-sky model that could replace the current SASRAB global horizontal irradiance and direct normal irradiances reported during clear-sky conditions.
-
a physics based GOES Satellite product for use in nrel s national solar radiation database
29th European Photovoltaic Solar Energy Conference and Exhibition, 2014Co-Authors: Manajit Sengupta, Aron Habte, Peter Gotseff, A. Weekley, Anthony Lopez, C. Molling, Andrew K. HeidingerAbstract:The National Renewable Energy Laboratory (NREL), University of Wisconsin, and National Oceanic Atmospheric Administration are collaborating to investigate the integration of the Satellite Algorithm for Shortwave Radiation Budget (SASRAB) products into future versions of NREL's 4-km by 4-km gridded National Solar Radiation Database (NSRDB). This paper describes a method to select an improved clear-sky model that could replace the current SASRAB global horizontal irradiance and direct normal irradiances reported during clear-sky conditions.