Every winter the Arctic ice cap is penned in by curved barriers of ice spanning the straits that lead out of the Arctic Ocean. Now it seems that some of these ice arches are failing to form. The resulting exodus of sea ice into the Atlantic and Pacific could affect ocean circulation and marine life.

Detailed studies of ancient climate have revealed that the onset of Europe's "Big Freeze", 13,000 years ago, was anything but glacial.

It's time to wise up to the ecological pawprint of your furry friend

Without drastic cuts in emissions, the Transpolar Drift, one of the Arctic's most powerful currents and a key disperser of pollutants, is likely to disappear because of global warming.

Forget barrages, dams or tidal turbines

Warmer temperatures and earlier melting of sea ice are causing polar bears to go hungry. The number of undernourished bears has tripled in a 20-year period.

Grind it down, pour in a sprinkle here and a dash there, and wait for results. That's the recipe for helping the oceans to absorb more of our carbon dioxide emissions: add limestone. It may not only help reduce global warming but could even reinvigorate ailing coral reefs.

If you do like to be beside the seaside, it might be best to avoid beaches near major ports. The mix of sea salt, ship fumes and city smoke leads to a chemical reaction that encourages the formation of ozone smog, adding to the pollution that forms in cities. James Roberts from the National Oceanic and Atmospheric Administration Earth System Research Laboratory in Boulder, Colorado, and his colleagues have developed a mass spectrometer that can detect nitryl chloride (NO2Cl) - a chemical that aids the formation of ozone.