Assessment of Night-Time Lighting for Global Terrestrial Protected and Wilderness Areas

Protected areas (PAs) play an important role in biodiversity conservation and ecosystem integrity. However, human development has threatened and affected the function and effectiveness of PAs. The Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) night-time stable light (NTL) data have proven to be an effective indicator of the intensity and change of human-induced urban development over a long time span and at a larger spatial scale. We used the NTL data from 1992 to 2013 to characterize the human-induced urban development and studied the spatial and temporal variation of the NTL of global terrestrial PAs. We selected seven types of PAs defined by the International Union for Conversation of Nature (IUCN), including strict nature reserve (Ia), wilderness area (Ib), national park (II), natural monument or feature (III), habitat/species management area (IV), protected landscape/seascape (V), and protected area with sustainable use of natural resources (VI). We evaluated the NTL digital number (DN) in PAs and their surrounding buffer zones, i.e., 0–1 km, 1–5 km, 5–10 km, 10–25 km, 25–50 km, and 50–100 km. The results revealed the level, growth rate, trend, and distribution pattern of NTL in PAs. Within PAs, areas of types V and Ib had the highest and lowest NTL levels, respectively. In the surrounding 1–100 km buffer zones, type V PAs also had the highest NTL level, but type VI PAs had the lowest NTL level. The NTL level in the areas surrounding PAs was higher than that within PAs. Types Ia and III PAs showed the highest and lowest NTL growth rate from 1992 to 2013, respectively, both inside and outside of PAs. The NTL distributions surrounding the Ib and VI PAs were different from other types. The areas close to Ib and VI boundaries, i.e., in the 0–25 km buffer zones, showed lower NTL levels, for which the highest NTL level was observed within the 25–100 km buffer zone. However, other types of PAs showed the opposite NTL patterns. The NTL level was lower in the distant buffer zones, and the lowest night light was within the 1–25 km buffer zones. Globally, 6.9% of PAs are being affected by NTL. Conditions of wilderness areas, e.g., high latitude regions, Tibetan Plateau, Amazon, and Caribbean, are the least affected by NTL. The PAs in Europe, Asia, and North America are more affected by NTL than South America, Africa, and Oceania

Remote sensing of night lights: a review and an outlook for the future

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordRemote sensing of night light emissions in the visible band offers a unique opportunity to directly observe human activity from space. This has allowed a host of applications including mapping urban areas, estimating population and GDP, monitoring disasters and conflicts. More recently, remotely sensed night lights data have found use in understanding the environmental impacts of light emissions (light pollution), including their impacts on human health. In this review, we outline the historical development of night-time optical sensors up to the current state of the art sensors, highlight various applications of night light data, discuss the special challenges associated with remote sensing of night lights with a focus on the limitations of current sensors, and provide an outlook for the future of remote sensing of night lights. While the paper mainly focuses on space borne remote sensing, ground based sensing of night-time brightness for studies on astronomical and ecological light pollution, as well as for calibration and validation of space borne data, are also discussed. Although the development of night light sensors lags behind day-time sensors, we demonstrate that the field is in a stage of rapid development. The worldwide transition to LED lights poses a particular challenge for remote sensing of night lights, and strongly highlights the need for a new generation of space borne night lights instruments. This work shows that future sensors are needed to monitor temporal changes during the night (for example from a geostationary platform or constellation of satellites), and to better understand the angular patterns of light emission (roughly analogous to the BRDF in daylight sensing). Perhaps most importantly, we make the case that higher spatial resolution and multispectral sensors covering the range from blue to NIR are needed to more effectively identify lighting technologies, map urban functions, and monitor energy use.European Union Horizon 2020Helmholtz AssociationNatural Environment Research Council (NERC)Chinese Academy of ScienceLeibniz AssociationIGB Leibniz Institut

National scale spatial variation in artificial light at night

This is the final version. Available on open access from MDPI via the DOI in this recordThe disruption to natural light regimes caused by outdoor artificial nighttime lighting has significant impacts on human health and the natural world. Artificial light at night takes two forms, light emissions and skyglow (caused by the scattering of light by water, dust and gas molecules in the atmosphere). Key to determining where the biological impacts from each form are likely to be experienced is understanding their spatial occurrence and how this varies with other landscape factors. To examine this, we used data from the Visible Infrared Imaging Radiometer Suite (VIIRS) day/night band and the World Atlas of Artificial Night Sky Brightness to determine covariation in (a) light emissions, and (b) skyglow, with human population density, landcover, protected areas and roads in Britain. We demonstrate that although artificial light at night increases with human density, the amount of light per person decreases with increasing urbanization (with per capita median direct emissions three times greater in rural than urban populations, and per capita median skyglow eleven times greater). There was significant variation in artificial light at night within different landcover types, emphasizing that light pollution is not a solely urban issue. Further, half of English National parks have higher levels of skyglow than light emissions indicating their failure to buffer biodiversity from pressures that artificial lighting poses. The higher per capita emissions in rural than urban areas provide different challenges and opportunities to mitigating the negative human health and environmental impacts of light pollution.Natural Environment Research Council (NERC

Schutz der Nacht : Lichtemissionen im UNESCO-Welterbe Schweizer Alpen Jungfrau-Aletsch

The development of electric lighting in the 20th century has led to widespread artificial light at night. The alteration of the natural brightness at night is called light pollution and has direct or indirect effects on human health, animals and ecosystems. This study focuses on the assessment of light pollution in the UNESCO World Heritage Swiss Alps Jungfrau-Aletsch using nighttime satellite data. Data from the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite were analyzed using the Visible Infrared Imaging Radiometer Suite Day-Night Band (VIIRS DNB) from 2012 to 2021. The results indicate minimal light pollution within the World Heritage area, which can be attributed to the low level of infrastructure. There was a decrease in light emissions in urban areas around the World Heritage, which can be mainly attributed to the sensor’s insensitivity to the blue light emitted from white LEDs. However, expanding industrial sites such as Lonza in Visp and the Rhone Valley floor showed a significant increase in light emissions. Negative ecological impacts could not be identified within the World Heritage based on light emission levels. However, a newly developed hazard assessment revealed isolated vulnerable sites at the edge of the area near human settlements. Further monitoring is recommended for areas such as Ausserberg on the Lötschberg south ramp and the "Schwarzmönch" wildlife reserve in the Lauterbrunnen Valley. Although nighttime satellite data proved useful for assessing light pollution, limitations were also noted. Incomplete detection of white LEDs, which can increase ecological impacts, was a significant constraint. Inconsistencies in the satellite data and the need for intercalibration were also noted. Additional data sets and local measurements are suggested to increase accuracy. The results indicate that light pollution within the World Heritage Site is minimal, but should be further observed in some areas. By understanding the extent and potential impact of light pollution, effective measures can be developed to protect the unique natural and cultural landscape of the UNESCO World Heritage Swiss Alps Jungfrau-Aletsch.Die Entwicklung der elektrischen Beleuchtung im 20. Jahrhundert hat zu einer starken Verbreitung von künstlichem Licht in der Nacht geführt. Die Veränderung der natürlichen nächtlichen Helligkeit wird als Lichtverschmutzung bezeichnet und hat direkte oder indirekte Auswirkungen auf die menschliche Gesundheit, Tiere und Ökosysteme. Diese Studie konzentriert sich auf die Bewertung der Lichtverschmutzung im UNESCO-Welterbe Schweizer Alpen Jungfrau-Aletsch anhand von nächtlichen Satellitendaten. Es wurden Daten des Suomi National Polarorbiting Partnership (Suomi NPP) Satelliten mit dem Visible Infrared Imaging Radiometer Suite Day-Night Band (VIIRS DNB) von 2012 bis 2021 analysiert. Die Ergebnisse deuten auf eine minimale Lichtverschmutzung innerhalb des Welterbe-Gebiets hin, was auf die geringe Infrastruktur zurückzuführen ist. In städtischen Gebieten um die Welterbe-Region war ein Rückgang der Lichtemissionen zu verzeichnen, was hauptsächlich mit der Unempfindlichkeit des Sensors gegenüber blauem Licht von weisser LED-Beleuchtung begründet werden kann. Expandierende Industriestandorte wie die Lonza in Visp und der Rhonetalboden wiesen jedoch eine deutliche Zunahme der Lichtemissionen auf. Negative ökologische Auswirkungen konnten im Welterbe-Gebiet anhand der Lichtemissionswerte nicht festgestellt werden. Eine neu entwickelte Gefährdungsabschätzung ergab jedoch vereinzelte gefährdete Standorte am Rande des Gebiets in der Nähe menschlicher Siedlungen. Für Gebiete wie Ausserberg an der Lötschberg-Südrampe und der Wildruhezone «Schwarzmönch» im Lauterbrunnental wird ein weiteres Monitoring empfohlen. Obwohl sich die nächtlichen Satellitendaten für die Beurteilung der Lichtverschmutzung als nützlich erwiesen, wurden auch Limitationen festgestellt. Die unvollständige Erfassung weisser LEDs, welche die ökologischen Auswirkungen verstärken können, stellte eine erhebliche Einschränkung dar. Unstimmigkeiten in den Satellitendaten und die Notwendigkeit einer Kalibrierung wurden ebenfalls festgestellt. Zusätzliche Datensätze und lokale Messungen werden vorgeschlagen, um die Genauigkeit zu erhöhen. Die Ergebnisse zeigen, dass die Lichtverschmutzung innerhalb des Welterbes minimal ist, aber in einigen Bereichen Anlass zur Sorge gibt. Durch das Verständnis des Ausmasses und der möglichen Auswirkungen der Lichtverschmutzung können wirksame Massnahmen zum Schutz der einzigartigen Natur- und Kulturlandschaft des UNESCO-Welterbes Schweizer Alpen Jungfrau-Aletsch entwickelt werden

Pelagic Habitat Use by Juvenile Reef Fishes in the Gulf of Mexico

The assemblage composition, abundance, frequency of occurrence, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described. This study, a component of the NOAA-supported Offshore Nekton Sampling and Analysis Program, is the first to examine juvenile reef fish distributions across the oceanic northern Gulf of Mexico after the Deepwater Horizon oil spill. Results presented here are derived from a 3-month, spring/summer research cruise in 2011 on the M/V Meg Skansi. A 10-m2 MOCNESS midwater trawl was used to sample 45 stations from the surface to a depth of 1500 m, both day and night. Seven reef fish orders, 30 reef fish families and 119 reef fish species were collected. Initial analysis has revealed the presence of juveniles of some species in locations where adults are not known to occur. Juveniles were found almost exclusively in the uppermost 200m of the water column. A greater number of individuals were collected in nighttime trawls. Surprisingly, some individuals were sampled between 1000–1500 m. During the MS7 sampling program, hydrographic profiles of the water column were recorded. This information provides the hydrographic background setting against which the coastal reef fish distributions in the offshore pelagic habitat of the Gulf of Mexico can be characterized. Results of fish distributions as a function of location (relative to the shelf break) and major mesoscale oceanographic features will be presented

The use of satellite data, meteorology and land use data to define high resolution temperature exposure for the estimation of health effects in Italy

Introduction. Despite the mounting evidence on heat-related health risks, there is limited evidence in suburban and rural areas. The limited spatial resolution of temperature data also hinders the evidence of the differential heat effect within cities due to individual and area-based characteristics. Methods. Satellite land surface temperature (LST), observed meteorological and spatial and spatio-temporal land use data were combined in mixed-effects regression models to estimate daily mean air temperature with a 1x1km resolution for the period 2000-2010. For each day, random intercepts and slopes for LST were estimated to capture the day-to-day temporal variability of the Ta–LST relationship. The models were also nested by climate zones to better capture local climates and daily weather patterns across Italy. The daily exposure data was used to estimate the effects and impacts of heat on cause-specific mortality and hospital admissions in the Lazio region at municipal level in a time series framework. Furthermore, to address the differential effect of heat within an urban area and account for potential effect modifiers a case cross-over study was conducted in Rome. Mean temperature was attributed at the individual level to the Rome Population Cohort and the urban heat island (UHI) intensity using air temperature data was calculated for Rome. Results. Exposure model performance was very good: in the stage 1 model (only on grid cells with both LST and observed data) a mean R2 value of 0.96 and RMSPE of 1.1°C and R2 of 0.89 and 0.97 for the spatial and temporal domains respectively. The model was also validated with regional weather forecasting model data and gave excellent results (R2=0.95 RMSPE=1.8°C. The time series study showed significant effects and impacts on cause-specific mortality in suburban and rural areas of the Lazio region, with risk estimates comparable to those found in urban areas. High temperatures also had an effect on respiratory hospital admissions. Age, gender, pre-existing cardiovascular disease, marital status, education and occupation were found to be effect modifiers of the temperature-mortality association. No risk gradient was found by socio-economic position (SEP) in Rome. Considering the urban heat island (UHI) and SEP combined, differential effects of heat were observed by UHI among same SEP groupings. Impervious surfaces and high urban development were also effect modifiers of the heat-related mortality risk. Finally, the study found that high resolution gridded data provided more accurate effect estimates especially for extreme temperature intervals. Conclusions. Results will help improve heat adaptation and response measures and can be used predict the future heat-related burden under different climate change scenarios.Open Acces

Global land surface temperature influenced by vegetation cover and PM2.5 from 2001 to 2016

Land surface temperature (LST) is an important parameter to evaluate environmental changes. In this paper, time series analysis was conducted to estimate the interannual variations in global LST from 2001 to 2016 based on moderate resolution imaging spectroradiometer (MODIS) LST, and normalized difference vegetation index (NDVI) products and fine particulate matter (PM2.5) data from the Atmospheric Composition Analysis Group. The results showed that LST, seasonally integrated normalized difference vegetation index (SINDVI), and PM2.5 increased by 0.17 K, 0.04, and 1.02 �g/m3 in the period of 2001–2016, respectively. During the past 16 years, LST showed an increasing trend in most areas, with two peaks of 1.58 K and 1.85 K at 72�N and 48�S, respectively. Marked warming also appeared in the Arctic. On the contrary, remarkable decrease in LST occurred in Antarctic. In most parts of the world, LST was affected by the variation in vegetation cover and air pollutant, which can be detected by the satellite. In the Northern Hemisphere, positive relations between SINDVI and LST were found; however, in the Southern Hemisphere, negative correlations were detected. The impact of PM2.5 on LST was more complex. On the whole, LST increased with a small increase in PM2.5 concentrations but decreased with a marked increase in PM2.5. The study provides insights on the complex relationship between vegetation cover, air pollution, and land surface temperature

Impacts of Nitrogen Enrichment on Corals – A Remote Sensing Approach

Anthropogenic activities have resulted in ever-increasing threats to coral reefs globally, wherein the rate of environmental changes have exceeded the historical capacity of corals to adapt. This has threatened the persistence of coral ecosystems and their associated ecosystem services, which billions of people rely on for their livelihoods. The most prevalent stressor is nitrogen enrichment, which while present naturally, is exacerbated by the anthropogenic input of nutrients via the discharge of agricultural and urban waste waters. The focus is to answer the central research question of how nitrogen enrichment impacts corals, and how it interacts with other stressors with particular focus on the Caribbean Sea. Nitrogen enrichment directly impacts corals by promoting algae dominance of coral ecosystems, disrupting coral symbiotic relationships, increasing disease prevalence, and indirectly by creating hypoxic conditions and affecting coral calcification rates. The case study of the PNN Los Corales del Rosario y San Bernardo served to demonstrate the use of remote sensing for monitoring chlorophyl-a concentrations and sea surface temperatures, where these two water quality parameters were negatively correlated from 2003 to 2021. Promoting the use of these tools is of crucial importance in the Caribbean region, where many local communities lack accessible resources available for environmental management. It is evident that, in addition to reducing nitrogen enrichment events, managers need to implement coordinated management to reduce multiple environmental stressors that affects corals. Finally, it is necessary to provide education that allows local communities to not only identify the challenges that corals face but also the solutions moving forward