Fluxes of gaseous elemental mercury on a Mediterranean coastal grassland

TY - JOUR

T1 - Fluxes of gaseous elemental mercury on a Mediterranean coastal grassland

AU - Polyzou, Christiana

AU - Loupa, Glykeria

AU - Trepekli, Aikaterini

AU - Rapsomanikis, Spyridon

PY - 2019/9/1

Y1 - 2019/9/1

N2 - Coastal rural areas can be a source of elemental mercury, but the potential influence of their topographic and climatic particularities on gaseous elemental mercury (GEM) fluxes have not been investigated extensively. In this study, gaseous elemental mercury was measured over Mediterranean coastal grassland located in Northern Greece from 2014 to 2015 and GEM fluxes were evaluated utilizing Monin-Obukhov similarity theory. The GEM fluxes ranged from -50.30 to 109.69 ng m-2 h-1 with a mean value equal to 10.50 ± 19.14 ng m-2 h-1. Concerning the peak events, with high positive and low negative GEM fluxes, those were recorded from the morning until the evening. Rain events were a strong contributing factor for enhanced GEM fluxes. The enhanced turbulent mixing under daytime unstable conditions led to greater evasion and positive GEM fluxes, while, during nighttime periods, the GEM evasion is lower, indicating the effect of atmospheric stability on GEM fluxes. The coastal grassland with its specific characteristics influences the GEM fluxes and this area could be characterized as a source of elemental mercury. This study is one of the rare efforts in the research community to estimate GEM fluxes in a coastal natural site based on aerodynamic gradient method.

AB - Coastal rural areas can be a source of elemental mercury, but the potential influence of their topographic and climatic particularities on gaseous elemental mercury (GEM) fluxes have not been investigated extensively. In this study, gaseous elemental mercury was measured over Mediterranean coastal grassland located in Northern Greece from 2014 to 2015 and GEM fluxes were evaluated utilizing Monin-Obukhov similarity theory. The GEM fluxes ranged from -50.30 to 109.69 ng m-2 h-1 with a mean value equal to 10.50 ± 19.14 ng m-2 h-1. Concerning the peak events, with high positive and low negative GEM fluxes, those were recorded from the morning until the evening. Rain events were a strong contributing factor for enhanced GEM fluxes. The enhanced turbulent mixing under daytime unstable conditions led to greater evasion and positive GEM fluxes, while, during nighttime periods, the GEM evasion is lower, indicating the effect of atmospheric stability on GEM fluxes. The coastal grassland with its specific characteristics influences the GEM fluxes and this area could be characterized as a source of elemental mercury. This study is one of the rare efforts in the research community to estimate GEM fluxes in a coastal natural site based on aerodynamic gradient method.

KW - Aegean Sea

KW - Aerodynamic gradient method

KW - Coastal area

KW - Gaseous elemental mercury

KW - GEM fluxes

KW - Mediterranean Basin

KW - Monin-Obukhov similarity theory

U2 - 10.3390/atmos10090485

DO - 10.3390/atmos10090485

M3 - Journal article

AN - SCOPUS:85072252318

SN - 2073-4433

VL - 10

JO - ATMOSPHERE

JF - ATMOSPHERE

IS - 9

M1 - 485

ER -