World Video | Defence | Foreign Affairs | Natural Events | Trade | NZ in World News | NZ National News Video | NZ Regional News | Search


UN Reports Signs of Antarctic Ozone Depletion this Year

New York, Aug 23 2011 1:10PM
Signs of ozone depletion are again appearing over the Antarctic, the United Nations reported today, adding that prevailing temperatures and polar stratospheric clouds indicate that the degree of ozone loss this year will most likely be about average in comparison to the past decade.

However, the World Meteorological Organization (WMO) noted that it is still too early to make a definitive statement on the level of depletion of ozone – which serves as a shield to protect life on Earth from harmful levels of ultraviolet rays – for 2011.

In Antarctica, the so-called ozone hole is an annually recurring winter/spring phenomenon due to the existence of extremely low temperatures in the stratosphere and the presence of ozone-depleting substances.

Despite international progress in cutting production and consumption of ozone-depleting chemicals, they have a long atmospheric lifetime and it will take several decades before their concentrations are back to pre-1980 levels, according to the WMO’s first Antarctic Ozone Bulletin for this year.

In mid-August, the ozone hole area was normal compared to recent years – larger than in 2008 and 2010, but smaller than in 2009, according to the bulletin. As the sun returns to Antarctica after the polar night, it is expected that ozone destruction will speed up. The extent of ozone loss will to a large extent depend on meteorological conditions.

The depletion of the ozone layer is also due to a very cold winter in the stratosphere, which is the second major layer of the Earth’s atmosphere, just above the troposphere.

WMO and the scientific community will use ozone observations from the ground, weather balloons and satellites, as wells as meteorological data, to monitor the development of the ozone hole in the coming weeks and months.

The onset of ozone depletion varies considerably from one year to the next, depending on the position of the polar vortex and availability of daylight after the polar night.

Measurements with ground based instruments and with weather balloons show first signs of ozone depletion at some sites located close to the vortex edge.

As the sun returns to Antarctica after the polar night, it is expected that ozone destruction will speed up, according to the WMO bulletin.


© Scoop Media

World Headlines


UN: UNHCR Chief Urges Better Support For 13 Million 'Exhausted' And Displaced Syrians
UN High Commissioner for Refugees, Filippo Grandi, has urged greater international support for the more than 13 million Syrians who’ve been displaced in the past 10 years...More>>

>UN: Recent Kosovo-Serbia Tensions Could ‘Unravel Steady But Fragile Progress’

Tensions over vehicle licence plates and anti-smuggling operations, between authorities in Kosovo and Serbia, in recent weeks, may contribute to unravelling “steady but fragile progress made in rebuilding trust among communities” in Kosovo and Serbia...

ITUC: Nobel Prize In Economics Explodes Minimum Wage And Jobs Myth

The prize was awarded to David Card, Joshua Angrist and Guido Imbens for real-world research in the 1990s that demonstrated, empirically, that the idea touted by conservative economists that higher minimum wages mean fewer jobs is not based on fact... More>>

Focus On: UN SDGs

UN: With Clock Ticking, Sustainable Transport Key To Global Goals
From electric cars and buses to zero-carbon producing energy sources, new and emerging technologies along with innovative policy changes, are critical for combating climate change. But to be effective, they must ensure that transport strategies benefit everyone, including the poorest... More>>

COP26: 7 Climate Action Highlights To Remember

A September to remember, a pivotal month for climate action commitments. From the United Nations General Assembly week to the final pre-COP meeting, last month was an important time to build momentum... More>>

UN: Global Leaders Set To Act To Increase Energy Access While Reducing Emissions At First UN Energy Summit In 40 Years

Significant new commitments for financing clean energy, increasing renewables and improving access to electricity are expected to be announced on 24 September at the UN High-level Dialogue on Energy... More>>