Seismic Location of the 4 August 2020 Beirut Port Chemical Explosion

Abstract On 4 August 2020 Lebanon’s capital, Beirut, was rocked by a sequence of colocated fires and chemical explosions that left hundreds of people dead, thousands injured and homeless, demolished the city’s seaport, and heavily damaged the surrounding neighborhoods and businesses. The event was well recorded by many regional seismic stations in and around the eastern Mediterranean Sea. Using a network of 58 stations, 105 regional seismic phases, and a Bayesian methodology places the event at 1.8 km south of the ground-truth location, the seaport warehouse. Achieving this accuracy is significant, considering very limited local seismic data were available to use in this study. The location bias is attributed, in large part, to a small but statistically significant difference in the Moho velocity for sea paths compared with continental paths. The depth to the Moho is generally consistent with the iasp91 model. Concurrent to the port explosion is a series of unrelated small explosions, 11 s apart, attributed to a seismic survey that was being carried out at the time in the eastern Mediterranean Sea using air guns.

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Molecular Identification and Characterization of Vibrio Species and Mycobacterium Species in Wild and Cultured Marine Fish from the Eastern Mediterranean Sea

Microorganisms ◽

10.3390/microorganisms8060863 ◽

2020 ◽

Vol 8 (6) ◽

pp. 863 ◽

Cited By ~ 2

Author(s):

Yael Regev ◽

Nadav Davidovich ◽

Ran Berzak ◽

Stanley C. K. Lau ◽

Aviad P. Scheinin ◽

...

Keyword(s):

Mediterranean Sea ◽

Marine Fish ◽

Eastern Mediterranean ◽

Vibrio Species ◽

Wild Fish ◽

Fish Populations ◽

Pathogenic Microorganisms ◽

Mycobacterium Species ◽

Eastern Mediterranean Sea ◽

Significant Difference

In contrast to numerous documented pathogens and infectious diseases of aquaculture, there is a lack of baseline data and information regarding pathogenic agents’ prevalence in wild marine fish populations. This study focused on two common fish pathogenic microorganisms, namely Mycobacterium species and Vibrio species, both of which are known to be major causes of fish loss, occasionally to the extent of being a limiting factor in fish production. Both microorganisms are known as zoonotic agents. In total, 210 wild marine indigenous and Lessepsian fish from four different species from the eastern Mediterranean Sea were sampled and tested for Vibrio species and Mycobacterium species during a two-year period (2016–2017). Using PCR with 16S rRNA primers, we detected different strain variations of Mycobacterium species and Vibrio species and, based on the sequencing results, the overall prevalence for Vibrio species in wild fish in 2016 was significantly higher compared to 2017. No significant difference was detected for Mycobacterium species prevalence in wild fish between 2016 and 2017. In addition, 72 gilthead seabream (Sparus aurata) from an Israeli offshore marine farm were also examined during the two-year period (2017–2018). The results suggest that Mycobacterium species prevalence was significantly higher in 2018, while in 2017 there was no positive results for Mycobacterium species. In addition, there was no significant difference between both years in regard to the prevalence of Vibrio species for maricultured fish. These results highlight the necessity of continuous molecular monitoring in order to evaluate the prevalence of pathogenic microorganisms in both wild and cultured fish populations.

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The Sensitivity of Middle East Precipitation and Cloud Forecasts to Changes in Eastern Mediterranean Sea Surface Temperatures

10.21236/ada207864 ◽

1989 ◽

Author(s):

Stephen Brenner

Keyword(s):

Middle East ◽

Mediterranean Sea ◽

Eastern Mediterranean ◽

Sea Surface ◽

Sea Surface Temperatures ◽

Eastern Mediterranean Sea ◽

Surface Temperatures

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Comparison of Hydrocarbon-Degrading Consortia from Surface and Deep Waters of the Eastern Mediterranean Sea: Characterization and Degradation Potential

Energies ◽

10.3390/en14082246 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2246

Author(s):

Georgia Charalampous ◽

Efsevia Fragkou ◽

Konstantinos A. Kormas ◽

Alexandre B. De Menezes ◽

Paraskevi N. Polymenakou ◽

...

Keyword(s):

Mediterranean Sea ◽

Oil Spills ◽

Eastern Mediterranean ◽

Sole Source ◽

Eastern Mediterranean Sea ◽

Deep Waters ◽

Degradation Rates ◽

Polycyclic Aromatic ◽

Set Up

The diversity and degradation capacity of hydrocarbon-degrading consortia from surface and deep waters of the Eastern Mediterranean Sea were studied in time-series experiments. Microcosms were set up in ONR7a medium at in situ temperatures of 25 °C and 14 °C for the Surface and Deep consortia, respectively, and crude oil as the sole source of carbon. The Deep consortium was additionally investigated at 25 °C to allow the direct comparison of the degradation rates to the Surface consortium. In total, ~50% of the alkanes and ~15% of the polycyclic aromatic hydrocarbons were degraded in all treatments by Day 24. Approximately ~95% of the total biodegradation by the Deep consortium took place within 6 days regardless of temperature, whereas comparable levels of degradation were reached on Day 12 by the Surface consortium. Both consortia were dominated by well-known hydrocarbon-degrading taxa. Temperature played a significant role in shaping the Deep consortia communities with Pseudomonas and Pseudoalteromonas dominating at 25 °C and Alcanivorax at 14 °C. Overall, the Deep consortium showed a higher efficiency for hydrocarbon degradation within the first week following contamination, which is critical in the case of oil spills, and thus merits further investigation for its exploitation in bioremediation technologies tailored to the Eastern Mediterranean Sea.

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