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Author Kocifaj, M.; Kundracik, F.
Title Multi-wavelength radiometry of aerosols designed for more accurate night sky brightness predictions Type Journal Article
Year 2020 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 250 Issue Pages (down) 106998
Keywords Skyglow; Remote Sensing
Abstract Scattering by aerosols and gases cause a certain fraction of artificial light emitted upwards is redirected to the ground. Of all atmospheric constituents just the aerosols are most important modulators of night-sky brightness under cloudless conditions. Unlike most of the previous we highlight a crucial role of solar radiometry for determining the atmospheric optical depth before night-time observation is to be made. Aerosol optical depth at visible wavelengths extracted from the data measured provides then the information on size distribution or mean refractive index of aerosol particles that in turn are both necessary to make night sky brightness prediction more accurate. Therefore, combining daytime and night-time radiometry we can achieve accuracy much higher than ever before. This is due to significantly reduced uncertainty in aerosol properties.

The aerosol data are retrieved from a new portable multi-wavelength optical analyzer that operates Ocean Optics spectrometer. The equipment provides the radiance data from 350 nm to 1000 nm with spectral resolution of 1 nm. Due to high sun radiance levels we use a system of mirrors each reducing the signal to about 4%, while keeping the integration time short. The minimum integration time of 3 ms allows for detection of direct sunlight. The system developed is sensitive to small changes in the aerosol system, while showing a good detection limit even under low turbidity conditions. The system performance is demonstrated in field experiment conducted shortly after front passage when most of aerosol particles is effectively removed by rain.
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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 no
Call Number GFZ @ kyba @ Serial 2906
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Author Min, M.; Zheng, J.; Zhang, P.; Hu, X.; Chen, L.; Li, X.; Huang, Y.; Zhu, L.
Title A low-light radiative transfer model for satellite observations of moonlight and earth surface light at night 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 (down) 106954
Keywords Remote Sensing; Instrumentation
Abstract Lunar sun-reflected light can be effectively measured through a low-light band or a day/night band (DNB) implemented on space-based optical sensors. Based on moonlight, nocturnal observations for artificial light sources at night can be achieved. However, to date, an open-sourced and mature Low-Light Radiative Transfer Model (LLRTM) for the further understanding of the radiative transfer problem at night is still unavailable. Therefore, this study develops a new LLRTM at night with the correction of the lunar and active surface light sources. First, the radiative transfer equations with an active surface light source are derived for the calculation based on the lunar spectral irradiance (LSI) model. The simulation from this new LLRTM shows a minimal bias when compared with the discrete ordinates radiative transfer (DISORT) model. The simulated results of radiance and reflectance at the top of the atmosphere (TOA) also show that the surface light source has a remarkable impact on the radiative transfer process. In contrast, the change in the lunar phase angle has minimal influence. Also, comparing with space-based DNB radiance observations, LLRTM shows the potential to simulate space-based low-light imager observations under an effective surface light source condition during the night.
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Corporate Author Thesis
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 no
Call Number GFZ @ kyba @ Serial 2850
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Author Zheng, Z.; Wu, Z.; Chen, Y.; Yang, Z.; Marinello, F.
Title Exploration of eco-environment and urbanization changes in coastal zones: A case study in China over the past 20 years Type Journal Article
Year 2020 Publication Ecological Indicators Abbreviated Journal Ecological Indicators
Volume 119 Issue Pages (down) 106847
Keywords Remote Sensing
Abstract With the rapid development of urbanization and population migration, since the 20th century, the natural and eco-environment of coastal areas have been under tremendous pressure due to the strong interference of human response. To objectively evaluate the coastal eco-environment condition and explore the impact from the urbanization process, this paper, by integrating daytime remote sensing and nighttime remote sensing, carried out a quantitative assessment of the coastal zone of China in 2000–2019 based on Remote Sensing Ecological Index (RSEI) and Comprehensive Nighttime Light Index (CNLI) respectively. The results showed that: 1) the overall eco-environmental conditions in China's coastal zone have shown a trend of improvement, but regional differences still exist; 2) during the study period, the urbanization process of cities continued to advance, especially in seaside cities and prefecture-level cities in Jiangsu and Shandong, which were much higher than the average growth rate; 3) the Coupling Coordination Degree (CCD) between the urbanization and eco-environment in coastal cities is constantly increasing, but the main contribution of environmental improvement comes from non-urbanized areas, and the eco-environment pressure in urbanized areas is still not optimistic. As a large-scale, long-term series of eco-environment and urbanization process change analysis, this study can provide theoretical support for mesoscale development planning, eco-environment condition monitoring and environmental protection policies from decision-makers.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1470160X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 3113
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Author Bará, S.; Rigueiro, I.; Lima, R.C.
Title Monitoring transition: Expected night sky brightness trends in different photometric bands Type Journal Article
Year 2019 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 239 Issue Pages (down) 106644
Keywords Skyglow; Remote Sensing; Instrumentation
Abstract Several light pollution indicators are commonly used to monitor the effects of the transition from outdoor lighting systems based on traditional gas-discharge lamps to solid-state light sources. In this work we analyze a subset of these indicators, including the artificial zenithal night sky brightness in the visual photopic and scotopic bands, the brightness in the specific photometric band of the widely used Sky Quality Meter (SQM), and the top-of-atmosphere radiance detected by the VIIRS-DNB radiometer onboard the satellite Suomi-NPP. Using a single-scattering approximation in a layered atmosphere we quantitatively show that, depending on the transition scenarios, these indicators may show different, even opposite behaviors. This is mainly due to the combined effects of the changes in the sources' spectra and angular radiation patterns, the wavelength-dependent atmospheric propagation processes and the differences in the detector spectral sensitivity bands. It is suggested that the possible presence of this differential behavior should be taken into account when evaluating light pollution indicator datasets for assessing the outcomes of public policy decisions regarding the upgrading of outdoor lighting systems.
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Corporate Author Thesis
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 no
Call Number GFZ @ kyba @ Serial 2810
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Author Beresford, A.E.; Donald, P.F.; Buchanan, G.M.
Title Repeatable and standardised monitoring of threats to Key Biodiversity Areas in Africa using Google Earth Engine Type Journal Article
Year 2020 Publication Ecological Indicators Abbreviated Journal Ecological Indicators
Volume 109 Issue Pages (down) 105763
Keywords Remote Sensing
Abstract Key Biodiversity Areas (KBAs) are sites that make significant contributions to the global persistence of biodiversity, but identification of sites alone is not sufficient to ensure their conservation. Monitoring is essential if pressures on these sites are to be identified, priorities set and appropriate responses developed. Here, we describe how analysis of freely available data on a cloud-processing platform (Google Earth Engine) can be used to assess changes in three example remotely sensed threat indicators (fire frequency, tree loss and night-time lights) over time on KBAs in Africa. We develop easily repeatable methods with shared code that could be applied across any geographic area and could be adapted and applied to other datasets as they become available. Fire frequency was found to have increased significantly on 12.4% of KBAs and 15.9% of ecoregions, whilst rates of forest loss increased significantly on 24.3% of KBAs and 22.6% of ecoregions. There was also evidence of significant increases in night-time lights on over half (53.3%) of KBAs and 39.6% of ecoregions between 1992 and 2013, and on 11.6% of KBAs and 53.0% of ecoregions between 2014 and 2018.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1470160X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2707
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