Mustafa ASFUR, Ruppin Academic Center / Faculty of Marine Sciences, Israel
Jacob SILVERMAN, Ruppin Academic Center / Faculty of Marine Sciences, Israel
In the last century the Mediterranean Sea has undergone significant changes due to the effects of global and regional anthropogenic changes. Global warming and the erection of the Aswan High Dam (AHD) have caused substantial changes in the chemical and physical properties of seawater. The combined effects of these changes resulted in salinization of Levantine Surface Waters (LSW) from ~38.95 to ~39.4 since the erection of the AHD. During the same period the increase of atmospheric CO2 resulted in ocean acidification (OA) of LSW on the order of -0.1 pH units. In this study we tested the combined effects of salinization and OA on the intensity of laboratory generated electrical sparks, which are considered to be analogous to cloud to sea-surface intensity of lightning discharges (LFI). Based on these experimental results we estimate that LFI in the Levantine Sea may have increased by as much as 12±1.4% since the1960’s. Furthermore, assuming that salinization and acidification of LSW will continue at current trends, the LFI is predicted to increase by 23±2.9% relative to the pre 1960’s by 2050.
Mots clés : Lightning intensity|Mediterranean Sea|salinization|ocean acidification|total alkalinity
A102932MA