Satellites show that the recent ozone hole over Antarctica was the smallest seen in the past decade. Long-term observations also reveal that Earth’s ozone has been strengthening following international agreements to protect this vital layer of the atmosphere.
According to the ozone sensor on Europe’s MetOp weather satellite, the hole over Antarctica in 2012 was the smallest in the last 10 years.
The instrument continues the long-term monitoring of atmospheric ozone started by its predecessors on the ERS-2 and Envisat satellites.
Since the beginning of the 1980s, an ozone hole has developed over Antarctica during the southern spring - September to November - resulting in a decrease in ozone concentration of up to 70%.
Ozone depletion is more extreme in Antarctica than at the North Pole because high wind speeds cause a fast-rotating vortex of cold air, leading to extremely low temperatures. Under these conditions, human-made chlorofluorocarbons - CFCs - have a stronger effect on the ozone, depleting it and creating the infamous hole.
For the past 25 years, it seemed that we’d pretty much solved the ozone problem. In the 1970s and 80s, people around the world grew increasingly alarmed as research revealed that chemicals we were producing—such as CFCs, used in refrigeration— had started destroying the crucial ozone layer, high up in the atmopshere, that protects us from the sun’s harmful UV radiation. In response, world governments came together to sign the Montreal Protocol in 1987, which phased out the production of ozone-depleting chemicals. The concentration of these chemicals in the atmosphere leveled off within a decade.
Yesterday, though, Harvard scientists hit us with some bad news: It looks as if climate change could actually cause the depletion of the ozone layer to resume on a wide scale, with grim implications for the United States.
“If you were to ask me where this fits into the spectrum of things I worry about, right now it’s at the top of the list,” said professor James Anderson in a press release, discussing his team’s paper, published online in Science. “What this research does is connect, for the first time, climate change with ozone depletion, and ozone loss is directly tied to increases in skin cancer incidence, because more ultraviolet radiation is penetrating the atmosphere.”
The revelation comes from the researchers’ observation that warm-temperature summer storms can force moisture high up into the stratosphere, a layer of the atmosphere that sits about 6 miles above our heads. Typically, storm updrafts are halted at a boundary just below the stratosphere, but in a series of observation flights above the U.S., the team saw that storms with sufficient power injected water vapor into the stratosphere via convection currents.
Well, this is frightening! Scientists are observing dramatic and significant changes in the skin of whales as a result of sunburn.
If you click the link, the story indicates that scientists aren’t certain why this is happening, but one candidate for the cause is exposure to increased levels of ultra-violet radiation as a result of ozone depletion or changes in cloud cover.
London, England (CNN) — Whales in Mexico’s Gulf of California are showing worsening signs of sunburn according to new report published Wednesday.
Photos and skin samples gathered by scientists from the UK’s Zoological Society of London (ZSL) and Mexico’s Interdisciplinary Marine Science Center revealed blisters and changes in skin pigmentation in blue whales, fin whales and sperm whales.