Feb 23, 2017

Aerosol‐driven increase in Arctic sea ice over the middle of the 20th Century

Gagné, Marie‐Ève, Fyfe, John C., Gillett, Nathan P., Polyakov, Igor V., Flato, Gregory M.
Geophysical Research Letters
  • Examines updated observational datasets without climatological infilling
    • Defines infilling as the use of climatological averages to fill in the gaps in observations
  • Finds that there was an increase in sea ice concentration in the Eastern Arctic between 1950 and 1975
  • Runs climate model simulations using CanESM2
  • States that sulphur dioxide emissions, which lead to the formation of sulphate aerosols, peaked around 1980, causing a sharp increase in the burden of sulphate between the 1950s and 1970s
  • Simulations show that the cooling contribution of aerosols offset the warming effect of increasing greenhouse gases over the mid-twentieth century, resulting in the expansion of the Arctic sea ice cover
  • Results challenge the perception that Arctic sea ice extent was unperturbed by human influence until the 1970s