Levin N.
The impact of seasonal changes on observed nighttime brightness from 2014 to 2015 monthly VIIRS DNB composites. Remote Sensing of Environment [Internet]. 2017 :150.
Publisher's VersionAbstractThe VIIRS-DNB sensor launched in 2011 offers the remote sensing community improved capabilities for monitoring and quantifying nighttime brightness. So far, most studies of temporal changes in nighttime lights were focused on examining inter-annual trends or on sudden changes in light emission, related to demographic and economic reasons. Here, the recently released two year (2014-2015) set of monthly cloud-free VIIRS-DNB composites was used to explicitly examine seasonal changes in nighttime lights and their correspondence with seasonality of land cover in Northern and Central America. It was found that monthly changes in nighttime brightness were positively correlated with monthly changes in snow cover and in albedo, and negatively correlated with monthly changes in NDVI. These correlations were strongest in urban areas in the northeast of the USA, where high correlation coefficient values (>0.8) were obtained. Seasonality in nighttime brightness is thus an important factor to consi
Turco M, Levin N, Tessler N, Saaroni H.
Recent changes and relations among drought, vegetation and wildfires in the Eastern Mediterranean: The case of Israel. Global and Planetary Change [Internet]. 2017;151 (Climate Variability and Change in the Mediterranean Region) :28 - 35.
Publisher's VersionAbstractOn-going changes in drought, vegetation and wildfires in Israel provide a key example of possible future evolution in transition areas at the border between Mediterranean and arid climates. Here we present multiple lines of evidence suggesting that drought conditions in Israel, representing the eastern Mediterranean, have increased during the period 1980–2014. Drought conditions were calculated using the Standardized Precipitation Evapotranspiration Index (SPEI), the Standardized Precipitation Index (SPI) and the Standardized Soil Moisture Index (SSI). A 30-year series (1982–2011) of monthly Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) indicates generally positive trends in winter and spring and negative ones in summer and autumn, except in the transition zone between the southern Negev desert and the Mediterranean climate region, where a statistically significant negative trend in all seasons was found. Available ground observations suggest that fire
Shafran-Nathan R, Levy I, Levin N, Broday DM.
Ecological bias in environmental health studies: the problem of aggregation of multiple data sources. Air Quality, Atmosphere & Health [Internet]. 2017;(4) :411.
Publisher's VersionAbstractEcological bias may result from interactions between variables that are characterized by different spatial and temporal scales. Such an ecological bias, also known as aggregation bias or cross-level-bias, may occur as a result of using coarse environmental information about stressors together with fine (i.e., individual) information on health outcomes. This study examines the assumption that distinct within-area variability of spatial patterns of the risk metrics and confounders may result from artifacts of the aggregation of the underlying data layers, and that this may affect the statistical relationships between them. In particular, we demonstrate the importance of carefully linking information layers with distinct spatial resolutions and show that environmental epidemiology studies are prone to exposure misclassification as a result of statistically linking distinctly averaged spatial data (e.g., exposure metrics, confounders, health indices). Since area-level confounders and expo
Levin N, Jablon P-E, Phinn S, Collins K.
Coastal dune activity and foredune formation on Moreton Island, Australia, 1944-2015. Aeolian Research [Internet]. 2017 :107.
Publisher's VersionAbstract* Dune activity and foredunes were quantified between 1944 and 2015 using remote sensing. * Wind power (DP, RDP, RDP/DP) and wave climate were analyzed for Moreton Island. * Transgressive dunes on Moreton Island are stabilizing despite an increase in DP. * Foredune formation in the 1960s-1970s was found responsible for dune stabilization.
Katsanevakis S, Mackelworth P, Coll M, Fraschetti S, Ma?i? V, Giakoumi S, Jones P, Levin N, Albano P, Badalamenti F, et al. Advancing marine conservation in European and contiguous seas with the MarCons Action. [Internet]. 2017.
Publisher's VersionAbstractCumulative human impacts have led to the degradation of marine ecosystems and the decline of biodiversity in the European and contiguous seas. Effective conservation measures are urgently needed to reverse these trends. Conservation must entail societal choices, underpinned by human values and worldviews that differ between the countries bordering these seas. Social, economic and political heterogeneity adds to the challenge of balancing conservation with sustainable use of the seas. Comprehensive macro-regional coordination is needed to ensure effective conservation of marine ecosystems and biodiversity of this region. Under the European Union Horizon 2020 framework programme, the MarCons COST action aims to [...]
Levin N, Lechner AM, Brown G.
An evaluation of crowdsourced information for assessing the visitation and perceived importance of protected areas. Applied Geography [Internet]. 2017 :115.
Publisher's VersionAbstractParks and protected areas provide a wide range of benefits, but methods to evaluate their importance to society are often ad hoc and limited. In this study, the quality of crowdsourced information from Public Participation GIS (PPGIS) and Volunteered Geographic Information (VGI) sources (Flickr, OpenStreetMap (OSM), and Wikipedia) was compared with visitor counts that are presumed to reflect social importance. Using the state of Victoria, Australia as a case study, secondary crowdsourced VGI data, primary crowdsourced (PPGIS data) and visitor statistics were examined for their correspondence and differences, and to identify spatial patterns in park popularity. Data completeness – the percent of protected areas with data – varied between sources, being highest for OSM (90%), followed by Flickr (41%), PPGIS (24%), visitation counts (5%), and Wikipedia articles (4%). Statistically significant correlations were found between all five measures of popularity for protected areas. Using ste
Levin N, Zhang Q.
A global analysis of factors controlling VIIRS nighttime light levels from densely populated areas. Remote Sensing of Environment [Internet]. 2017 :366.
Publisher's VersionAbstractRemote sensing of nighttime lights has been shown as a good surrogate for estimating population and economic activity at national and sub-national scales, using DMSP satellites. However, few studies have examined the factors explaining differences in nighttime brightness of cities at a global scale. In this study, we derived quantitative estimates of nighttime lights with the new VIIRS sensor onboard the Suomi NPP satellite in January 2014 and in July 2014, with two variables: mean brightness and percent lit area. We performed a global analysis of all densely populated areas (n=4153, mostly corresponding to metropolitan areas), which we defined using high spatial resolution Landscan population data. National GDP per capita was better in explaining nighttime brightness levels (0.60