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Levin, N., & Phinn, S. (2016). Illuminating the capabilities of Landsat 8 for mapping night lights. Remote Sensing of Environment, 182, 27–38.
Abstract: Remote sensing of night-lights has been enhanced in recent years with the availability of the new VIIRS Day and Night band, the commercial EROS-B satellite and astronaut photographs from the International Space Station. However, dedicated space-borne multispectral sensors offering radiance calibrated night lights imagery are yet to be launched. Here we examined the capabilities of Landsat 8 to acquire night time light images of the Earth. Examining seven night-time Landsat 8 scenes, we found that brightly lit areas in both urban (Berlin, Las Vegas, Nagoya and Tel-Aviv) and gas flares (Basra, Kuwait) areas were detected in all eight bands of Landsat 8. The threshold for detection of lit areas was approximately 0.4 W/m2/&#956;m/sr in bands 1–5 and 8 of Landsat 8. This threshold level was higher than Landsat dark noise levels, and slightly lower than post launch Landsat 8 OLI band dependent noise equivalent radiance difference levels. Drawing on this, we call on the USGS to plan an annual night-time acquisition of urban and gas flares areas globally, and to enable the performance of the future Landsat 10 to be established in a way that it will be sensitive enough to image the Earth at night, thus performing as Nightsat during the night.
Keywords: Remote Sensing; Instrumentation
http://alandb.darksky.org/show.php?record=1452
Allik, T., Ramboyong, L., Roberts, M., Walters, M., Soyka, T., Dixon, R., et al. (2016). Enhanced oil spill detection sensors in low-light environments. In Proc. SPIE 9827, Ocean Sensing and Monitoring VIII, 98270B (May 17, 2016). SPIE.
Abstract: 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.
Keywords: Instrumentation; Sensors; Cameras; Long wavelength infrared; Short wave infrared radiation; Spectroscopy; Calibration; Remote sensing; Water; Near infrared; Night vision
Zoogman, P., Liu, X., Suleiman, R. M., Pennington, W. F., Flittner, D. E., Al-Saadi, J. A., et al. (2016). Tropospheric emissions: Monitoring of pollution (TEMPO). Journal of Quantitative Spectroscopy and Radiative Transfer, 186, 17–39.
Keywords: Instrumentation, Remote Sensing
Bierman, A., Figueiro, M. G., & Rea, M. S. (2011). Measuring and predicting eyelid spectral transmittance. J Biomed Opt, 16(6), 067011.
Abstract: The purpose of the present study was to objectively quantify the spectral transmittance of the eyelid. Reported here are data acquired using a technique that was developed to provide practical and accurate measurements of eyelid transmittance across the visible portion of the electromagnetic spectrum. The empirical data were analyzed in terms of the absorption and scattering characteristics of the constituents of skin to develop a method for predicting eyelid transmission. Results showed that the eyelid has a much higher optical density at short wavelengths than previously published. The mean +/- standard deviation (s.d.) optical density of the eyelid from 450 to 650 nm was 2.1 +/- 0.3 with an optical density range among subjects of approximately 1.0. The study results indicate that skin pigmentation is poorly correlated with eyelid transmission; eyelid transmission is most affected by wavelength-independent macromolecules in the eyelid as well as its overall thickness.
Keywords: Instrumentation; Human Health
Dobler, G., Ghandehari, M., Koonin, S. E., & Sharma, M. S. (2016). A Hyperspectral Survey of New York City Lighting Technology. Sensors (Basel), 16(12), 2047.
Abstract: Using side-facing observations of the New York City (NYC) skyline, we identify lighting technologies via spectral signatures measured with Visible and Near Infrared (VNIR) hyperspectral imaging. The instrument is a scanning, single slit spectrograph with 872 spectral channels from 0.4-1.0 mu m. With a single scan, we are able to clearly match the detected spectral signatures of 13 templates of known lighting types. However, many of the observed lighting spectra do not match those that have been measured in the laboratory. We identify unknown spectra by segmenting our observations and using Template-Activated Partition (TAP) clustering with a variety of underlying unsupervised clustering methods to generate the first empirically-determined spectral catalog of roughly 40 urban lighting types. We show that, given our vantage point, we are able to determine lighting technology use for both interior and exterior lighting. Finally, we find that the total brightness of our scene shows strong peaks at the 570 nm Na – II , 595 nm Na – II and 818 nm Na – I lines that are common in high pressure sodium lamps, which dominate our observations.
Keywords: Remote Sensing; Instrumentation; Lighting