Total ice cover in sea (kg) over past 100 years plotted as time series

For this sub-challenge not enough data was available to complete it. The choice was made to focus on sea ice extent and sea ice thickness instead of cover in kg. The data on this topic is widely spread and freely available.

Major gaps in this challenge include information on ice cover mass.

For an interactive map with data on sea ice please go to http://www.emodnet-physics.eu/map/ and click on “CMEMS – Arctic sea ice”.

Sea Ice extent in Northern Hemisphere
Figure 1: Sea Ice extent in the Northern Hemisphere in January, from 1979 to 2016, in million square km. Datasource: NSIDC.

Sea Ice concentration
Figure 2: Sea Ice concentration from 1850 to 2010. Datasource: NODC.

Arctic September sea-ice extent
Figure 3: Arctic September sea-ice extent from observations (thick red line) and 13 Coupled Model Intercomparison Project phase 3 (CMIP3) models, together with the multi-model ensemble mean (solid black line) and one standard deviation range of model estimates (dotted black line). Models with more than one ensemble member are indicated with an asterisk. Note that these are September means, not yearly minima. (Adapted from Stroeve and others, 2007; courtesy of J. Stroeve.) (source: Kattsov et al. 2010)

Reconstruction of Arctic summer
Figure 4: Reconstruction of Arctic summer sea ice variation. (a) Forty-year smoothed reconstructed late-summer Arctic sea ice extent, with 95% confidence interval, and yearly ice duration in the (b) Chukchi Sea and (c) Fram strait. (Source: Walsh 2013)

For this sub-challenge, the following sources were used: