Study Shows Arctic Sea Ice Reached Lowest Point On Modern Record… In The 1940s, Not Today!

by C. Rotter, Jan 24, 2021 in WUWT

Regular NoTricksZone author Kenneth Richards notes on Twitter

Apparently Arctic sea ice volume was as low in the 1940s as it has been in the 2000s.

And the highest sea ice volume of the last 100 years was about 1979 – the year the Arctic sea ice record begins.


Guillian Van Achter1, Leandro Ponsoni1, François Massonnet1, Thierry Fichefet1, and Vincent Legat2

  • 1Georges Lemaitre Center for Earth and Climate Research, Earth and Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
  • 2Institute of Mechanics, Materials and Civil Engineering, Applied Mechanics and Mathematics, Université Catholique de Louvain, Louvain-la-Neuve, Belgium

Correspondence: Guillian Van Achter ( Received: 04 Dec 2019 – Discussion started: 10 Dec 2019 – Revised: 17 Jul 2020 – Accepted: 09 Sep 2020 – Published: 21 Oct 2020


We use model simulations from the CESM1-CAM5-BGC-LE dataset to characterise the Arctic sea ice thickness internal variability both spatially and temporally. These properties, and their stationarity, are investigated in three different contexts: (1) constant pre-industrial, (2) historical and (3) projected conditions. Spatial modes of variability show highly stationary patterns regardless of the forcing and mean state. A temporal analysis reveals two peaks of significant variability, and despite a non-stationarity on short timescales, they remain more or less stable until the first half of the 21st century, where they start to change once summer ice-free events occur, after 2050.

How to cite. Van Achter, G., Ponsoni, L., Massonnet, F., Fichefet, T., and Legat, V.: Brief communication: Arctic sea ice thickness internal variability and its changes under historical and anthropogenic forcing, The Cryosphere, 14, 3479–3486,, 2020.1