Impact of a Severe Dust Event on Diurnal Behavior of Surface Water Temperature in Subtropical Lake Kinneret

Abstract

Dust impact on lake surface water temperature (SWT) over lakes, located in the Eastern Mediterranean, has not yet been discussed in previous publications. We investigated the effect of an extreme dust intrusion on the diurnal behavior of SWT in Lake Kinneret, appearing from 7–9 September 2015. This was carried out using METEOSAT and in-situ observations of SWT. In the presence of dust, METEOSAT SWT decreased along with increasing dust pollution both in the daytime and nighttime. This contradicted in-situ measurements of SWT at a depth of 20 cm which increased to 1.2 °C in the daytime and to 1 °C in the nighttime, compared to SWT on clear-sky September 6. The in-situ radiometer measurements of upwelling longwave radiation (ULWR) provided us with a criterion for assessing the reliability of METEOSAT and in-situ observations of SWT. Using this criterion, we found that, in the presence of dust, in-situ SWT was in line, whereas METEOSAT SWT contradicted in-situ ULWR. Considering in-situ ULWR is determined by actual SWT, we concluded that, in the presence of dust, in-situ SWT were capable of reproducing Kinneret SWT, while METEOSAT was incapable of doing so. An observed increase in daytime air temperature during the dust intrusion contributed to an increase in daytime Kinneret SWT. In the presence of maximal dust pollution on September 8, atmospheric humidity (ρv) exceeded by 30% that on clear-sky September 6. This increase in ρv was observed in the absence of moisture advection indicating that dust intrusion can cause additional evaporation from Lake Kinneret and, consequently, intensify its drying up.

Lake and Atmospheric Heatwaves Caused by Extreme Dust Intrusion in Freshwater Lake Kinneret in the Eastern Mediterranean

“…Therefore, in the daytime, in the presence of dust pollution, both shortwave solar radiation and longwave thermal radiation influenced the SWT in the lake. The above-mentioned results are in line with the findings by Kishcha et al [22] based on in-situ measurements of water temperature at a depth of 20 cm. We examined the day-to-day variations in the daily maximal SWT (SWT-MAX) and minimal SWT (SWT-MIN) in September 2015.…”

“…Kishcha et al [22] found increasing absolute humidity (ρv) above Lake Kinneret on three dusty days from 7 to 9 September 2015. In this study, we analyzed the day-to-day variations in the daily maximal absolute humidity (ρv-MAX) at St. A on the lake during the observed LHW and AHW in September 2015.…”

“…They discussed the fact that dust transport from desert regions in northern Syria was responsible for the severe dust intrusion over Israel: dust plumes penetrated Israel from northeast to southwest. MODIS-Terra satellite imagery had started showing the presence of some amounts of dust pollution over the Jordan Rift valley on September 7 at 10:30 local time (LT) and significant amounts of dust pollution on September 8 and 9 [22]. Using ICON-ART model data, Gasch et al [29] showed that on dusty 8 September 2015, dust aerosol optical depth (AOD) reached 1.5 over the Zemah station near Lake Kinneret.…”

“…Kishcha et al [22] analyzed the impact of an extreme dust intrusion on the diurnal behavior of SWT in Lake Kinneret, which appeared in September 2015. Their study showed that the extreme dust intrusion noticeably influenced Lake Kinneret's SWT: in situ measurements of water temperature at a depth of 20 cm showed an increase of ~1 °C in the daytime and in the nighttime.…”

Spatio-Temporal Variability of the Aerosol Optical Depth over the Gorky and Cheboksary Reservoirs in 2022–2023

“…This finding is essential for the development of atmospheric correction algorithms for remote sensing data over highly productive waters in the Gorky Reservoir. In addition, desert dust could directly influence the surface water temperature in freshwater lakes (causing a decrease due to dust radiative effects or even a noticeable increase) and the absolute atmospheric humidity over inland water areas [23].…”