A preliminary investigation of light pollution over bunkering areas in Maltese coastal waters

Abstract

Malta, being an island, has a number of marine activities occurring all around its shoreline. One of these many marine activities includes a number of bunkering areas that are in operation around the clock, and therefore emit light throughout the night. The bunkering areas around Malta are relatively busy considering that Malta is in the centre of the Mediterranean and therefore an ideal location for ships to stop and make use of the services that are provided by the Maltese bunkering areas. Since light pollution is a recent phenomenon, there aren’t many regulations set in place to control the amount of light pollution that is given off by these bunkering areas. This in turn, is having an effect on numerous protected populations of sea birds. These can be found nesting and breeding in cliff faces and other habitats found on the Maltese shoreline very close to many bunkering sites. The main aim of this study is to quantify the amount of light pollution that is coming from three well defined bunkering areas found around the coast of Malta by using data products derived from satellite imagery taken by the day-night band (DNB) which is onboard the VIIRS satellite. In particular, light intensity levels over Bunkering Area 1, Bunkering Area 4, and Hurd’s Bank between 2015 and 2018, are investigated. Following the download and extraction of the monthly minimum, mean, and maximum night light levels over every area, a time series is created and correlated with the total number of AIS ship records received by a local station. The multi-year analysis allows for seasonal trends to be identified. A comparison between the three bunkering areas and the places that are known to have populations of sea birds will be made in order to make suggestions on how to better protect the endangered species found around the Maltese islands.