What is Hayli Gubbi's volcanic ash cloud? Know how it forms, travels and affects the environment

A high-altitude cloud of volcanic ash from Ethiopia, which drifted into the Indian region on Monday afternoon, is likely to move completely into China by Tuesday evening. The ash originated on Sunday from a rare eruption of the Hayli Gubbi volcano in the northeastern part of Ethiopia, near the Red Sea coastline. Travelling at altitudes commonly used by long-haul aircraft, the cloud poses risks such as reduced visibility and potential exposure to toxic gases like sulphur dioxide.

What is Hayli Gubbi's volcanic ash cloud?

It is a massive airborne cloud made of fine, sharp particles of rock, minerals and volcanic glass which are formed during a volcanic eruption, resulting from the magma inside shattering into microscopic pieces. Hot gases propel these materials upwards, and winds disperse them similarly to dust from a construction site, but on a large scale and at extremely high altitudes. It results in the ashes remaining suspended for days or even weeks, travelling great distances with atmospheric currents.

How does an ash cloud move?

All the trapped gases in a volcano expand violently after it erupts suddenly and release pressure from the rising magma. The mounting pressure results in an explosion, which breaks the magma into tiny particles and shoots them high into the atmosphere, forming what is known as an 'eruption plume'. Such a plume can reach astonishing heights of 15–20 kilometres above the surface of the Earth. Later, the ash cloud was carried along by powerful winds after reaching the upper layers, which can move across continents and multiple regions.

How Hayli Gubbi's volcanic ash cloud affects the environment

One of the powerful impacts of the ash cloud is that it can pose a major hazard to jet engines, as it can melt and solidify on turbine blades, causing engine failure and disrupting air travel. The next impact is the rise of SO2 levels in the air, affecting higher altitude regions, such as the Himalayas and Nepal, as it can irritate the respiratory system.

It also makes the skies appear darker and hazier than usual in regions it passes over. In addition, the interaction between volcanic gases and moisture in the atmosphere could potentially lead to light acidic rainfall in affected regions.