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Author Zheng, Q.; Weng, Q.; Wang, K.
Title Correcting the Pixel Blooming Effect (PiBE) of DMSP-OLS nighttime light imagery Type Journal Article
Year 2020 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment
Volume 240 Issue Pages 111707
Keywords *instrumentation; Remote Sensing
Abstract In the last two decades, the advance in nighttime light (NTL) remote sensing has fueled a surge in extensive research towards mapping human footprints. Nevertheless, the full potential of NTL data is largely constrained by the blooming effect. In this study, we propose a new concept, the Pixel Blooming Effect (PiBE), to delineate the mutual influence of lights from a pixel and its neighbors, and an integrated framework to eliminate the PiBE in radiance calibrated DMSP-OLS datasets (DMSPgrc). First, lights from isolated gas flaring sources and a Gaussian model were used to model how the PiBE functions on each pixel through point spread function (PSF). Second, a two-stage deblurring approach (TSDA) was developed to deconvolve DMSPgrc images with Tikhonov regularization to correct the PiBE and reconstruct PiBE-free images. Third, the proposed framework was assessed by synthetic data and VIIRS imagery and by testing the resulting image with two applications. We found that high impervious surface fraction pixels (ISF > 0.6) were impacted by the highest absolute magnitude of PiBE, whereas NTL pattern of low ISF pixels (ISF < 0.2) was more sensitive to the PiBE. By using TSDA the PiBE in DMSPgrc images was effectively corrected which enhanced data variation and suppressed pseudo lights from non-built-up pixels in urban areas. The reconstructed image had the highest similarity to reference data from synthetic image (SSIM = 0.759) and VIIRS image (r = 0.79). TSDA showed an acceptable performance for linear objects (width > 1.5 km) and circular objects (radius > 0.5 km), and for NTL data with different noise levels (<0.6σ). In summary, the proposed framework offers a new opportunity to improve the quality of DMSP-OLS images and subsequently will be conducive to NTL-based applications, such as mapping urban extent, estimating socioeconomic variables, and exploring eco-impact of artificial lights.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-4257 ISBN Medium
Area Expedition Conference
Notes Approved (up) no
Call Number GFZ @ kyba @ Serial 2940
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Author Wilson, T., & Xiong, X.
Title Intercomparison of the SNPP and NOAA-20 VIIRS DNB High-Gain Stage Using Observations of Bright Stars Type Journal Article
Year 2020 Publication IEEE Transactions on Geoscience and Remote Sensing Abbreviated Journal
Volume Issue Pages 1-8
Keywords Remote Sensing; Instrumentation
Abstract The Visible Infrared Imaging Radiometer Suite (VIIRS) on board the Suomi-NPP (SNPP) and NOAA-20 (N20) spacecrafts is a multispectral Earth-observing instrument with bands covering wavelengths from visible to long-wave infrared. Among these bands is a panchromatic day/night band (DNB) with a broad spectral response ranging from 500 to 900 nm, and a high dynamic range spanning over seven orders of magnitude, allowing for observations to take place during both daytime and nighttime. The DNB operates at three gain levels, with low- and mid-gain stages and two high-gain stages (HGSs). The HGS is capable of detecting dim city lights during Earth-view observations at night as well as bright stars through the instrument space-view port. Since SNPP and N20 are at opposite points of the same orbit, each VIIRS instrument is able to observe the same stars with the DNB in successive orbits. This will allow us to make a direct comparison of the relative calibration of each instrument using stars over a range of spectral classes. In this article, we develop methodology for accurately identifying target stars in order to make proper comparisons between the DNB HGS of each instrument. We then take observations from multiple stars in order to compute the ratio in the measured irradiance for each instrument as a function of spectral class. For K-type stars, which have the least spectral change over the DNB wavelength range, we measure a calibration bias between the SNPP and N20 DNB HGS of approximately 4%, which is stable over the duration of the N20 mission.
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Notes Approved (up) no
Call Number IDA @ intern @ Serial 2959
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Author Ngadiman, N. F., Shariff, N. N. M., & Hamidi, Z. S.
Title Sensor Technology for Night Sky Brightness Measurements in Malaysia Type Journal Article
Year 2020 Publication International Journal of Recent Technology and Engineering (IJRTE) Abbreviated Journal
Volume 8 Issue 6 Pages
Keywords Instrumentation
Abstract Artificial light at night is apparently showing to be a major contributor to the increase of sky brightness at night. The natural darkness in large regions of the world including Malaysia currently is at risk. Hence, some Night Sky Brightness (NSB) measurements in Malaysia were conducted by using several types of light sensors in order to serve quantitative data and spread awareness on this issue. This paper aims to analyze the sensor technology that have been used in night sky brightness measurement in Malaysia as well as to identify recent or significant advances and discoveries in this field of study. In this paper, the author adopted qualitative method through literature review from numerous conducted studies by other researchers in order to perceive better understanding on the use of dedicated light sensor in NSB related research. Starting from 2005 until now, it is noticeable that most of the light sensor used in the NSB studies in Malaysia was Sky Quality Meter (SQM) photometer, equipped with TSL237 sensor which has high irradiance responsivity 2.3kHz/(µW/cm2) @ λp = 524nm and 5 Milion:1 input dynamic range as well as able to sense down to 0.00002 Lux and has typical dark frequency down to 0.1 Hz. The result indicates the relative frequency of the SQM usage in NSB studies was 76% compared to PBM, APC, PMT and CDD of only 4% respectively. SQM has always been the choice of researchers in Malaysia to carry out their sky brightness measurements due to user-friendly implementation besides its reliable data obtained from TSL237 sensor which capable to convert the light directly to frequency without an amplifier or data converter. Thus, the nonlinearities and voltage offsets in the data can be circumvented. A fairly good development of sensor that have been utilized in NSB studies can be discerned patently besides NSB studies will always look forward for a better sensor to further enhance the efforts to map sky brightness for preserving the potential dark sky areas for the sake of astronomy.
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Language Summary Language Original Title
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Call Number IDA @ intern @ Serial 2968
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Author Coesfeld, J.; Kuester, T.; Kuechly, H.U.; Kyba, C.C.M.
Title Reducing Variability and Removing Natural Light from Nighttime Satellite Imagery: A Case Study Using the VIIRS DNB Type Journal Article
Year 2020 Publication Sensors Abbreviated Journal Sensors
Volume 20 Issue 11 Pages 3287
Keywords Remote Sensing; Instrumentation
Abstract Temporal variation of natural light sources such as airglow limits the ability of night light sensors to detect changes in small sources of artificial light (such as villages). This study presents a method for correcting for this effect globally, using the satellite radiance detected from regions without artificial light emissions. We developed a routine to define an approximate grid of locations worldwide that do not have regular light emission. We apply this method with a 5 degree equally spaced global grid (total of 2016 individual locations), using data from the Visible Infrared Imaging Radiometer Suite (VIIRS) Day-Night Band (DNB). This code could easily be adapted for other future global sensors. The correction reduces the standard deviation of data in the Earth Observation Group monthly DNB composites by almost a factor of two. The code and datasets presented here are available under an open license by GFZ Data Services, and are implemented in the Radiance Light Trends web application.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1424-8220 ISBN Medium
Area Expedition Conference
Notes Approved (up) no
Call Number GFZ @ kyba @ Serial 2988
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Author Kolláth, K.; Kolláth, Z.
Title On the feasibility of using ceilometer backscatter profile as input data for skyglow simulation Type Journal Article
Year 2020 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer
Volume in press Issue Pages in press
Keywords Skyglow; Instrumentation
Abstract Atmospheric conditions can significantly affect the sky brightness originating from artificial lights. Previous works studied the cloudiness, cloud base height, optical depth of cloud, aerosol optical depth and aerosol scale height as atmospheric parameters affecting night sky brightness. Instead of using these parameters as a simplification of the real cloud and aerosol profile, we processed the raw backscatter data of a laser ceilometer instrument. Sky brightness was obtained from camera images available at the same meteorological observation site. Case studies are shown in selected cases, where we analyzed the correspondences with the backscatter data and the camera images. We performed Monte Carlo simulations with the dominant light sources to verify the numerical predictions of sky radiances. Although the limitations of the ceilometer device to obtain optical properties of the atmosphere, ceilometers provide valuable source of data for evaluation of the light pollution measurements.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved (up) no
Call Number GFZ @ kyba @ Serial 2994
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