Jan 04

Antarctic Ozone Hole is Shrinking into Unusual Shape

The ozone hole that opens every year over the Antarctic is on course to be the smallest in three decades, scientists have said.

Researchers say the hole is also a particularly unusual shape this year, being heavily skewed towards South America instead of centring on the South Pole.

The rare shape – never before observed – indicates a significant distortion to the usual polar vortex, which maintains low temperatures in the stratosphere.

The hole is currently well under half the area that usually opens up by mid-September, and may have already reached its maximum size, a little smaller in area than the Antarctic continent.

Ozone, also known as trioxygen, is a gas formed in the upper atmosphere when electrical charges in the atmosphere combine with ultraviolet (UV) rays from the sun. The ozone layer absorbs the majority of the sun’s harmful UV radiation.

The hole disappears and reforms every year over the Antarctic due to the unique weather patterns that create incredibly cold circling winds above the pole.

According to the British Antarctic Survey, the hole had reached an area of 11 million square kilometres in early September, when the annual “spring warming” event kicked in much earlier than usual.

In 2018, the hole reached a maximum area of 22.9 square kilometres.

The bizarre shift in the ozone pattern is only the second time such a change in the hole’s behaviour has been observed.

In 2002, the polar vortex split in two, creating two separate ozone holes over the continent.

Read the full article at the Independent web site