The first world atlas of the artificial night sky brightness

We present the first World Atlas of the zenith artificial night sky brightness at sea level. Based on radiance calibrated high resolution DMSP satellite data and on accurate modelling of light propagation in the atmosphere, it provides a nearly global picture of how mankind is proceeding to envelope itself in a luminous fog. Comparing the Atlas with the U.S. Department of Energy (DOE) population density database we determined the fraction of population who are living under a sky of given brightness. About two thirds of the World population and 99% of the population in US (excluding Alaska and Hawaii) and EU live in areas where the night sky is above the threshold set for polluted status. Assuming average eye functionality, about one fifth of the World population, more than two thirds of the US population and more than one half of the EU population have already lost naked eye visibility of the Milky Way. Finally, about one tenth of the World population, more than 40% of the US population and one sixth of the EU population no longer view the heavens with the eye adapted to night vision because the sky brightness.Comment: 24 pages, 11 size-reduced PostScript figures, 3 statistical tables, accepted for publication in Monthly Notices of the Royal Astronomical Society, high-resolution original maps will be available soon from http://www.lightpollution.it/dmsp/ as zipped TIFF file

Estimating global economic well-being with unlit settlements

It is well established that nighttime radiance, measured from satellites, correlates with economic prosperity across the globe. In developing countries, areas with low levels of detected radiance generally indicate limited development – with unlit areas typically being disregarded. Here we combine satellite nighttime lights and the world settlement footprint for the year 2015 to show that 19% of the total settlement footprint of the planet had no detectable artificial radiance associated with it. The majority of unlit settlement footprints are found in Africa (39%), rising to 65% if we consider only rural settlement areas, along with numerous countries in the Middle East and Asia. Significant areas of unlit settlements are also located in some developed countries. For 49 countries spread across Africa, Asia and the Americas we are able to predict and map the wealth class obtained from ~2,400,000 geo-located households based upon the percent of unlit settlements, with an overall accuracy of 87%

The dimming of lights in China during the COVID-19 pandemic

A satellite survey of the cumulative radiant emissions from electric lighting across China reveals a large radiance decline in lighting from December 2019 to February 2020-the peak of the lockdown established to suppress the spread of COVID-19 infections. To illustrate the changes, an analysis was also conducted on a reference set from a year prior to the pandemic. In the reference period, the majority (62%) of China's population lived in administrative units that became brighter in March 2019 relative to December 2018. The situation reversed in February 2020, when 82% of the population lived in administrative units where lighting dimmed as a result of the pandemic. The dimming has also been demonstrated with difference images for the reference and pandemic image pairs, scattergrams, and a nightly temporal profile. The results indicate that it should be feasible to monitor declines and recovery in economic activity levels using nighttime lighting as a proxy. © 2020 by the authors

Remote sensing of the global light-fishing fleet: an analysis of interactions with oceanography, other fisheries and predators

The use of United States Defense Meteorological Satellite Program Operational Linescan System (DMSP-OLS) data has enabled the precise location of the distribution of the global light-fishing fleet over a six month period in relation to the large and general mesoscale oceanography of the ecological provinces where they occur. The squid catch in these light fisheries can be identified to genera or species in seven ecological provinces where DMSP-OLS imagery reveals light-fishing activities. The DMSP-OLS data provide the information needed to review the relationship between the squid fisheries using lights and other fisheries for finfish with better spatial resolution than has been previously possible using data for FAO statistical areas alone. This chapter demonstrates that 62–70%, and possibly up to something <96, of the world squid catch can be accounted for in the light fisheries identified in the images. This provides the opportunity of being more specific about possible interactions between cephalopod fisheries and declining groundfish stocks and allows the hypothesis about the inverse relationship between the trends in these fisheries. The ability to visualize the spatial distribution of fishing fleets and their movements over time with DMSP-OLS data has implications for the assessment and management of the exploited squid stocks

Contextual algorithm adapted for NOAA-AVHRR fire detection in Indonesia

International Journal of Remote Sensing20173415-3421IJSE

Impacts of Channel Morphodynamics on Fish Habitat Utilization

It is reasonable to expect that hydro-morphodynamic processes in fluvial systems can affect fish habitat availability, but the impacts of morphological changes in fluvial systems on fish habitat are not well studied. Herein we investigate the impact of morphological development of a cohesive meandering stream on the quality of fish habitat available for juvenile yellow perch (Perca flavescens) and white sucker (Catostomus commersonii). A three-dimensional (3D) morphodynamic model was first developed to simulate the hydro-morphodynamics of the study creek. The results of the morphodynamic model were then incorporated into a fish habitat availability assessment. The 3D hydro-morphodynamic model was successfully calibrated using an intensive acoustic Doppler current profiler (ADCP) spatial survey of the entire 3D velocity field and total station surveys of topographic changes in a meander bend in the study creek. Two fish sampling surveys were carried out at the beginning and the end of the study perio