Early Earthquake Warnings and Tsunami Risks in the Jordan Valley and Red Sea
תורגם ותומצת מתוך Al-Shams על ידי baba
Dr. Jalal Al-Dabik explained that early earthquake warnings detect initial seismic waves, providing 3 to 15 seconds of alert time for rapid precautions. He noted a potential technical issue with a recent alert in the Gulf of Aqaba and stressed the importance of specific activation criteria for warning systems. Al-Dabik identified the Jordan Rift Valley, Wadi Araba, and Dead Sea as high-risk seismic zones and discussed varying earthquake recurrence intervals for different fault lines. He also stated that tsunamis are unlikely in the Red Sea due to fault types, but earthquakes near Cyprus or Crete could generate waves reaching the region.
הידיעה ב-6 שורות · תקציר של baba
- Early earthquake warnings provide 3-15 seconds of alert time based on initial seismic waves, not predictions.
- Dr. Jalal Al-Dabik cited potential technical issues with a recent Gulf of Aqaba earthquake alert.
- The Jordan Rift Valley, Wadi Araba, and Dead Sea are identified as the highest seismic risk areas.
- Earthquake recurrence intervals vary widely, from 100 years in the northern Dead Sea to 1000 years near the Sea of Galilee.
- Tsunamis are unlikely in the Red Sea due to fault types, but could originate from Cyprus or Crete.
- Building codes aim to prevent collapse and protect lives during strong earthquakes, not necessarily avoid all damage.
Dr. Jalal Al-Dabik, Director of the Center for Urban Planning and Disaster Reduction, explained that early earthquake warning systems do not predict earthquakes hours or days in advance. Instead, they rely on detecting the initial seismic waves that occur at the moment of an earthquake, which precede the more destructive waves. These initial waves travel faster but are less impactful on humans. Detection devices can capture these waves and analyze the potential earthquake's magnitude within seconds, then transmit alerts to institutions and citizens. Al-Dabik estimates that the warning time in the region typically ranges from 3 to 15 seconds, potentially longer in areas farther from the epicenter. The effectiveness of these warnings depends on the distance from the epicenter and the density and distribution of monitoring stations.
Al-Dabik emphasized that early warnings are not intended for immediate evacuation, which could be more dangerous than staying in a safe location. Instead, they allow for quick precautions, such as moving away from hazardous areas and seeking appropriate shelter. These few seconds are particularly crucial for factories handling hazardous materials, trains, aircraft, and sensitive facilities, enabling them to slow down or take measures to mitigate damage. Regarding a recent alert following an earthquake in the southern Gulf of Aqaba, Al-Dabik suggested a possible technical malfunction in linking the earthquake's magnitude to the warning system's activation. He stressed that early warning systems should be activated based on specific criteria to prevent citizens from ignoring repeated false alarms.
Al-Dabik identified areas along the Jordan Rift Valley, Wadi Araba, and the Dead Sea as having the highest seismic risk. The risk decreases eastward and westward toward coastal areas, though soil type can significantly influence vibration intensity and damage. He noted that earthquake magnitude is not the sole determinant of damage; other factors include depth, proximity to populated areas, soil conditions, and building construction quality.
Discussing earthquake recurrence, Al-Dabik stated that active seismic zones have unique characteristics and potential recurrence intervals, though these are not fixed dates. He estimated that destructive earthquakes in the northern Dead Sea region might occur approximately every 100 years, while the period for the Fara'a-Carmel fault could range from 250 to 300 years, and for the northern Sea of Galilee region, it could be 800 to 1000 years. He reiterated that seismology is probabilistic, not deterministic, and the focus should be on preparedness through proper planning and adherence to earthquake-resistant building standards.
Regarding building resilience, Al-Dabik explained that international building codes set varying standards based on expected earthquake intensity. Ordinary buildings should withstand minor earthquakes without damage, and experience only minor damage to non-structural elements during moderate ones. Buildings designed to resist strong earthquakes might sustain cracks in walls and decorations, but the primary goal is to prevent collapse and protect lives. He cited Haiti and Japan as examples where damage was influenced not only by earthquake strength but also by construction quality, urban planning, and soil type, noting that poor planning and substandard buildings were major factors in Haiti's 2010 destruction.
Concerning the possibility of tsunamis in the Gulf of Aqaba and Red Sea, Al-Dabik outlined three necessary conditions: a powerful earthquake, an epicenter beneath the sea or ocean, and a vertical fault rupture. He explained that the fault types in the Red Sea, Wadi Araba, Dead Sea, and Jordan Rift Valley are predominantly transformational or translational, making the likelihood of significant tsunamis very limited. Earthquakes near Cyprus or Crete, however, could potentially generate tsunamis reaching the region's coasts in about 20 minutes from Cyprus and 45 minutes from Crete, with potential wave heights of 6 to 8 meters.
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