7.8 Earthquake Damage Mapping in Turkey and Syria

In the early hours of February 6th, 2023, a devastating earthquake of magnitude 7.8 in Gaziantep and magnitude 7.5 in Ekinözü struck Turkey and Syria, causing widespread loss of life and property. In the aftermath of the quake, more than 36,000 fatalities and numerous injuries were reported in one week. The unprecedented magnitude of the earthquake highlights the delicate nature of human life, yet it also underscores the resilience of the human spirit.

To assist in the aftermath of this disaster, the present study aims to assess the damage caused by the earthquake through the analysis of Sentinel-1 satellite data. We adopt a combination of coherence and displacement parameters to create a damage map of the affected areas. First, we calculate the difference in coherence between pre- and post-earthquake images and retain only pixels with a coherence value higher than 0.25 and a negative change in coherence. The resulting change in coherence is expressed as a percentage (diff_coherence_percent) after converting it to a percentage by multiplying it by 100.

Next, we enhance positive displacement values and take the absolute value of all displacement values, expressing the magnitude of displacement as a percentage (disp_percent) by dividing it by a threshold of 0.9 m and multiplying it by 100. Finally, we compute the damage percentage as the weighted average of both “diff_coherence_percent” and “disp_percent”, with equal weighting.

The results of our study can provide valuable insights into the impact of the earthquake and help guide recovery efforts by providing a map of the damage caused by the quake. Advanced radar technology and satellite imagery highlight the importance of utilizing cutting-edge tools in studying natural disasters and their impacts on communities.