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Author Muheim, R.; Phillips, J.B.; Akesson, S.
Title Polarized light cues underlie compass calibration in migratory songbirds Type Journal Article
Year 2006 Publication Science (New York, N.Y.) Abbreviated Journal Science
Volume 313 Issue 5788 Pages 837-839
Keywords Alaska; *Animal Migration; Animals; Calibration; Cues; *Flight, Animal; Geography; *Light; Magnetics; *Orientation; Seasons; Sparrows/*physiology; Sunlight
Abstract (down) Migratory songbirds use the geomagnetic field, stars, the Sun, and polarized light patterns to determine their migratory direction. To prevent navigational errors, it is necessary to calibrate all of these compass systems to a common reference. We show that migratory Savannah sparrows use polarized light cues from the region of sky near the horizon to recalibrate the magnetic compass at both sunrise and sunset. We suggest that skylight polarization patterns are used to derive an absolute (i.e., geographic) directional system that provides the primary calibration reference for all of the compasses of migratory songbirds.
Address Department of Animal Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden. rmuheim@vt.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0036-8075 ISBN Medium
Area Expedition Conference
Notes PMID:16902138 Approved no
Call Number IDA @ john @ Serial 243
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Author Lee, S.; Wang, W.; Cao, C.
Title JPSS-1 VIIRS DNB nonlinearity and its impact on SDR calibration Type Journal Article
Year 2015 Publication Proc. SPIE 9607, Earth Observing Systems XX, 2015 Abbreviated Journal
Volume Issue Pages 960717
Keywords Remote sensing; Suomi NPP; VIIRS DNB; JPSS-1; calibration
Abstract (down) During JPSS-1 VIIRS testing at Raytheon El Segundo, a larger than expected radiometric response nonlinearity was discovered in Day-Nigh Band (DNB). In addition, the DNB nonlinearity is aggregation mode dependent, where the most severe non-linear behavior are the aggregation modes used at high scan angles (<~50 degree). The DNB aggregation strategy was subsequently modified to remove modes with the most significant non-linearity. We characterized the DNB radiometric response using pre-launch tests with the modified aggregation strategy. The test data show the DNB non-linearity varies at each gain stages, detectors and aggregation modes. The non-linearity is most significant in the Low Gain Stage (LGS) and could vary from sample-to-sample. The non-linearity is also more significant in EV than in calibration view samples. The HGS nonlinearity is difficult to quantify due to the higher uncertainty in determining source radiance. Since the radiometric response non-linearity is most significant at low dn ranges, it presents challenge in DNB cross-stage calibration, an critical path to calibration DNB’s High Gain Stage (HGS) for nighttime imagery. Based on the radiometric characterization, we estimated the DNB on-orbit calibration accuracy and compared the expected DNB calibration accuracy using operational calibration approaches. The analysis showed the non-linearity will result in cross-stage gain ratio bias, and have the most significant impact on HGS. The HGS calibration accuracy can be improved when either SD data or only the more linearly behaved EV pixels are used in cross-stage calibration. Due to constrain in test data, we were not able to achieve a satisfactory accuracy and uniformity for the JPSS-1 DNB nighttime imagery quality. The JPSS-1 DNB nonlinearity is a challenging calibration issue which will likely require special attention after JPSS-1 launch.
Address NOAA National Environmental Satellite, Data, and Information Service, USA
Corporate Author Thesis
Publisher SPIE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1262
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Author Kyba, C.C.M.; Tong, K.P.; Bennie, J.; Birriel, I.; Birriel, J.J.; Cool, A.; Danielsen, A.; Davies, T.W.; Outer, P.N. den; Edwards, W.; Ehlert, R.; Falchi, F.; Fischer, J.; Giacomelli, A.; Giubbilini, F.; Haaima, M.; Hesse, C.; Heygster, G.; Hölker, F.; Inger, R.; Jensen, L.J.; Kuechly, H.U.; Kuehn, J.; Langill, P.; Lolkema, D.E.; Nagy, M.; Nievas, M.; Ochi, N.; Popow, E.; Posch, T.; Puschnig, J.; Ruhtz, T.; Schmidt, W.; Schwarz, R.; Schwope, A.; Spoelstra, H.; Tekatch, A.; Trueblood, M.; Walker, C.E.; Weber, M.; Welch, D.L.; Zamorano, J.; Gaston, K.J.
Title Worldwide variations in artificial skyglow Type Journal Article
Year 2015 Publication Scientific Reports Abbreviated Journal Sci. Rep.
Volume 5 Issue Pages 8409
Keywords Skyglow; light pollution; measurements; remote sensing; sky brightness; calibration
Abstract (down) Despite constituting a widespread and significant environmental change, understanding of artificial nighttime skyglow is extremely limited. Until now, published monitoring studies have been local or regional in scope, and typically of short duration. In this first major international compilation of monitoring data we answer several key questions about skyglow properties. Skyglow is observed to vary over four orders of magnitude, a range hundreds of times larger than was the case before artificial light. Nearly all of the study sites were polluted by artificial light. A non-linear relationship is observed between the sky brightness on clear and overcast nights, with a change in behavior near the rural to urban landuse transition. Overcast skies ranged from a third darker to almost 18 times brighter than clear. Clear sky radiances estimated by the World Atlas of Artificial Night Sky Brightness were found to be overestimated by ~25%; our dataset will play an important role in the calibration and ground truthing of future skyglow models. Most of the brightly lit sites darkened as the night progressed, typically by ~5% per hour. The great variation in skyglow radiance observed from site-to-site and with changing meteorological conditions underlines the need for a long-term international monitoring program.
Address Leibniz-Institute for Freshwater Ecology and Inland Fisheries, Berlin, Germany
Corporate Author Thesis
Publisher Nature Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1103
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Author Allik, T.; Ramboyong, L.; Roberts, M.; Walters, M.; Soyka, T.; Dixon, R.; Cho, J.
Title Enhanced oil spill detection sensors in low-light environments Type Conference Article
Year 2016 Publication Proc. SPIE 9827, Ocean Sensing and Monitoring VIII, 98270B (May 17, 2016) Abbreviated Journal Proc. SPIE 9827
Volume Issue Pages
Keywords Instrumentation; Sensors; Cameras; Long wavelength infrared; Short wave infrared radiation; Spectroscopy; Calibration; Remote sensing; Water; Near infrared; Night vision
Abstract (down) Although advances have been made in oil spill remote detection, many electro-optic sensors do not provide real-time images, do not work well under degraded visual environments, nor provide a measure of extreme oil thickness in marine environments. A joint program now exists between BSEE and NVESD that addresses these capability gaps in remote sensing of oil spills. Laboratory experiments, calibration techniques, and field tests were performed at Fort Belvoir, Virginia; Santa Barbara, California; and the Ohmsett Test Facility in Leonardo, New Jersey. Weathered crude oils were studied spectroscopically and characterized with LWIR, and low-light-level visible/NIR, and SWIR cameras. We designed and fabricated an oil emulsion thickness calibration cell for spectroscopic analysis and ground truth, field measurements. Digital night vision cameras provided real-time, wide-dynamic-range imagery, and were able to detect and recognize oil from full sun to partial moon light. The LWIR camera provided quantitative oil analysis (identification) for >1 mm thick crude oils both day and night. Two filtered, co-registered, SWIR cameras were used to determine whether oil thickness could be measured in real time. Spectroscopic results revealed that oil emulsions vary with location and weathered state and some oils (e.g., ANS and Santa Barbara seeps) do not show the spectral rich features from archived Deep Water Horizon hyperspectral data. Multi-sensor imagery collected during the 2015 USCG Airborne Oil Spill Remote Sensing and Reporting Exercise and the design of a compact, multiband imager are discussed.
Address Active EO Inc.
Corporate Author Thesis
Publisher SPIE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1475
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