In news– Several beaches in Mumbai and Goa witnessed black oil-emanating balls/ Tarballs(sticky tarballs with foul fuel smell) lying on the shore.
What are tarballs?
- They are dark-coloured, sticky balls of oil that form when crude oil floats on the ocean surface.
- A tarball is a blob of petroleum which has been weathered after floating in the ocean.
- Tarballs are formed by weathering of crude oil in marine environments.
- They are transported from the open sea to the shores by sea currents and waves.
- Tarballs are usually coin-sized and are found strewn on the beaches.
- However, over the years, they have become as big as basketballs and can weigh as much as 6-7 kgs.
- Most of the time, the presence of several tarballs indicate an oil spill.
- In India, Tarballs reach the western coast during the monsoon.
- According to the National Institute of Oceanography (NIO), wind and waves tear the oil slick into smaller patches that are scattered over a much wider area and various physical, chemical and biological processes (weathering) change the appearance of the oil.
- It is suspected that the oil comes from the large cargo ships in the deep sea and gets pushed to the shore as tarballs during monsoon due to wind speed and direction.
- The tarballs that travel towards the coast can get stuck to the fishing nets installed in the sea, making it difficult for fishermen to clean.
- In addition, it could affect marine life, especially filter feeders like clams and oysters.
- Microbes such as bacteria and fungi presumably play an important role in tarball degradation.