Comparison of night sky brightness above Zagreb and a nearby rural location 2014-2017

Scientific paper - Original scientific paper

• Title (croatian): Usporedba svjetline noćnoga neba iznad Zagreba i iznad bliske ruralne lokacije za razdoblje od 2014. do 2017.
• Author: Krešimir Pavlić https://orcid.org/0000-0003-3315-2900
• Author: Željko Andreić https://orcid.org/0000-0003-0175-8174
• Author's institution: University of Zagreb; Faculty of Mining, Geology and Petroleum Engineering; (Department of Mathematics, Informatics and Descriptive Geometry)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Geophysics
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mining, Petroleum and Geology Engineering

Abstract (english)

The results of monitoring light pollution near the center of Zagreb at the Faculty of Mining, Geology and Petroleum Engineering (RGN) for the period 2012 - 2017 were presented in a recent article (Andreić, 2018). The question that remained unanswered is how the night sky brightness behaves in the suburbs of Zagreb and in the nearby rural area. This article attempts to give some answers to this question by analyzing data gathered at the rural site of Merenje, located north of Zagreb. The main conclusion drawn is that the night sky brightness at both sites follows very similar patterns for clear sky conditions and is often similar for cloudy conditions, too. For both sites, no significant increase in zenithal night sky brightness was found in the observed period of 2014 - 2017. Thus, at least for the areas north of Zagreb that are in the shadow of Medvednica Mountain, the contribution of the light pollution from Zagreb and its growing outskirts remains unaltered. The main difference is in the level of the night sky brightness, the average for the RGN site being 16.9 mag/ arcsec2 and 18.9 mag/arcsec2 for the Merenje site. Additionally, the cloudy conditions enhance the light pollution of Zagreb a lot more, the difference being about 3.2 mag/arcsec2 for RGN, in contrast to 1.9 mag/arcsec2 for the Merenje site. No measurements exist for areas to the south, so no conclusions can be made for the situation there. Last, but not least, it was found that in cloudy conditions, the stronger light pollution of Zagreb is proportionally more enhanced by the clouds/fog than the smaller levels of light pollution at the Merenje site.

Abstract (croatian)

Rezultati praćenja svjetlosnoga onečišćenja u blizini središta Zagreba za razdoblje od 2012. do 2017. prikazani su u nedavnome članku (Andreić, 2018). Ostalo je neodgovoreno kako se ponaša svjetlina noćnoga neba u predgrađima Zagreba i u obližnjemu ruralnom području. Ovaj članak pokušava dati odgovor na to pitanje analizom podataka prikupljenih na jednome ruralnom lokalitetu sjeverno od Zagreba. Glavni je zaključak ovoga rada da svjetlina noćnoga neba na obama mjestima ima vrlo slične obrasce u uvjetima vedra neba, a često je slična i pri oblačnome vremenu. Za oba mjesta nije zabilježeno znatno povećanje zenitne svjetline noćnoga neba u razmatranome razdoblju od 2014. do 2017. Jedina razlika postoji u jačini svjetline noćnoga neba, za koju je srednja vrijednost za RGN lokaciju 16,9 mag/arcsec2, odnosno 18,9 mag/arcsec2 za lokaciju Merenje. Tako za područja sjeverno od Zagreba koja su u sjeni planine Medvednice nema znatnoga doprinosa svjetlosnoga onečišćenja iz Zagreba. Ne postoje mjerenja za područja južno od Zagreba, tako da se ne može donijeti zaključak o tamošnjoj situaciji. Na kraju je ustanovljeno da je u oblačnim uvjetima jače svjetlosno onečišćenje Zagreba proporcionalno pojačano oblacima/maglom od manjih razina svjetlosnoga onečišćenja na mjestu Merenje.

• Keywords (english): light pollution; night sky brightness; ALAN evolution; atmospheric effects
• Keywords (croatian): svjetlosno onečišćenje; svjetlina noćnoga neba; ALAN evolucija; atmosferski učinci
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Rudarsko-geološko-naftni zbornik
• Numbering: vol. 35, no. 2, pp. 45-55
• e-ISSN: 1849-0409
• DOI: https://doi.org/10.17794/rgn.2020.2.5
• URN:NBN: urn:nbn:hr:169:681395
• Publication: 2020
• Document URL: https://hrcak.srce.hr/237319
• Type of resource: Text
• Access conditions: Open access
• Created on: 2021-04-21 13:22:33