Arctic Sea Ice in CMIP6

• Published in: Geophysical Research Letters
• Main Authors: Notz, D., Dörr, J., Bailey, D.A., Blockley, E., Bushuk, M., Debernard, J.B., Dekker, E., DeRepentigny, P., Docquier, D., Fuckar, N. S., Fyfe, J.C., Jahn, A., Holland, M., Hunke, E., Iovino, D., Khosravi, N., Massonnet, François, Madec, G., O'Farrell, S., Petty, A., Rana, A., Roach, L., Rosenblum, E., Rousset, C., Semmler, Tido, Stroeve, Julienne, Tremblay, Bruno, Toyoda, T., Tsujino, H., Vancoppenolle, Martin
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Wiley 2020
• Subjects: Arctic; Arctic Ocean; Global warming; Sea ice
• Online Access: https://epic.awi.de/id/eprint/51815/; https://epic.awi.de/id/eprint/51815/1/Notz_2019.pdf; https://doi.org/10.1029/2019GL086749; https://hdl.handle.net/10013/epic.5da063f1-fa7c-40bf-9136-6d39793fc11f

We examine CMIP6 simulations of Arctic sea‐ice area and volume. We find that CMIP6 models produce a wide spread of mean Arctic sea‐ice area, capturing the observational estimate within the multi‐model ensemble spread. The CMIP6 multi‐model ensemble mean provides a more realistic estimate of the sensitivity of September Arctic sea‐ice area to a given amount of anthropogenic CO2 emissions and to a given amount of global warming, compared with earlier CMIP experiments. Still, most CMIP6 models fail to simulate at the same time a plausible evolution of sea‐ice area and of global mean surface temperature. In the vast majority of the available CMIP6 simulations, the Arctic Ocean becomes practically sea‐ice free (sea‐ice area < 1 million km2) in September for the first time before the year 2050 in each of the four emission scenarios SSP1‐1.9, SSP1‐2.6, SSP2‐4.5 and SSP5‐8.5 examined here.