London: Researchers in Australia have claimed that the hole in the ozone layer over Antarctica is on the road to recovery, 22 years after the Montreal Protocol to ban chlorofluorocarbons (CFCs) and related ozone-destroying chemicals came into force.
The team is the first to detect a recovery in baseline average springtime ozone levels in the region.
The West Antarctic Peninsula (WAP) and adjacent Scotia Sea support abundant wildlife populations, many of which were nearly extirpated by humans. This region is also among the fastest-warming areas on the planet, with 5–6 °C increases in mean winter air temperatures and associated decreases in winter sea-ice cover.
A novel explanation for the long-term temperature record in Antarctic ice cores invokes local solar radiation as the driving agent. This proposal will prompt palaeoclimate scientists to pause and to go back to basics.
The disintegration of ice shelves, reduced sea-ice and glacier extent, and shifting ecological zones observed around Antarctica highlight the impact of recent atmospheric and oceanic warming on the cryosphere.
In 2007, the Intergovernmental Panel on Climate Change highlighted an urgent need to assess the responses of marine ecosystems to climate change. Because they lie in a high-latitude region, the Southern Ocean ecosystems are expected to be strongly affected by global warming.
Fortunately for us, carbon monoxide (CO)—a toxic gas—is a very minor constituent of the atmosphere. It is produced by incomplete burning of fossil fuels and biomass (such as dry leaves and wood) and by the oxidation of methane and other volatile hydrocarbons in the atmosphere.
We present a 650-year Antarctic ice core record of concentration and isotopic ratios (δ13C and δ18O) of atmospheric carbon monoxide. Concentrations decreased by ~25% (14 parts per billion by volume) from the mid-1300s to the 1600s then recovered completely by the late 1800s.
