On the third day of Eid-ul-Azha, September 4, 2017, beachgoers in Karachi reported oil or oil-like substance washing ashore on the Clifton Beach. Geo News reported the incident here.
As a researcher in the field of radar remote sensing, it got me thinking whether we can spot it on satellite images, if incidentally acquired by a space-borne Synthetic Aperture Radar (SAR) sensor. Interestingly, I found some acquisitions acquired by the European Space Agency (ESA)’s Sentinel-1A sensor. Unfortunately there was no acquisition on the 4th of September. The closest acquisition before the suspected spill is on 01.09.2017 @ 01:26, and the latest is on 10.09.2017 @ 13:35. The good news is that the latest image shows no sign of ‘low brightness’ characteristic of oil slicks. However, in the image on 01.09, we do see some dark areas which are somewhat troubling.
Referring to the figure below, the dark areas immediately below the Clifton area made me nervous — if that is oil spill traveling towards the shoreline, it’s huge! But it’s probably not, since it’s just too huge to have gotten ignored! It’s likely a ‘look-alike’ , which may appear in the radar image indicating local calmness of the water. However, I’m no expert in oceanography, so I don’t make any claim about it. Nonetheless, it does cause to raise an eyebrow.
At the same time, there are two instances (marked in red) which do seem to be oil spills, perhaps in the wake of the very same vessels passing nearby. In each case, it extends more than 6 km. Since the image is now 12 days old, and we don’t observe the suspected spill in the latest image — it may have dispersed by now — the main lesson is that the “authorities should keep a closer look” in future!
I am open to feedback/comments from other fellow scientists/experts in the field of SAR/Remote-Sensing/Oceanography, especially if they fear I may have missed something.
Disclaimer: This is an analysis performed from “remote” sensing images. Authorities must confirm or reject the suspicions on the basis of local forensic evaluation.
About this post: This is a guest post by M. Adnan Siddique.