Arctic sea ice outlook at worst point in 125,000 years

Though temperatures were warmer during the last interglacial period, the greenhouse effect of atmospheric C02 is now melting more Arctic sea ice.

Sediment cores reveal that during the last interglacial period atmospheric CO2 levels were about 290 parts per million (ppm). Now the level is about 400 ppm. Credit: Peter ORR Photography/ Getty Images