[M-IS08] Global climate change driven by the Southern Ocean and the Antarctic Ice Sheet

[MIS08-07] Surface atmospheric and snow/ice physical conditions over the Antarctic ice sheet from 1991 to the present simulated by a polar regional climate model

★Invited Papers

*Masashi Niwano¹, Akihiro Hashimoto¹, Shun Tsutaki^2,3 (1.Meteorological Research Institute, 2.National Institute of Polar Research, 3.Department of Polar Science, The Graduate University of Advanced Studies, SOKENDAI)

Keywords:Antarctic ice sheet, climate, atmosphere, snow and ice, polar regional climate model

The mass loss from the Antarctic ice sheet is accelerating in recent years, and its pace is expected to increase in the future warmer climate. Because the mass loss from the Antarctic ice sheet can enhance global sea level rise substantially, it is crucial to understand the detailed response of the ice sheet surface to the changes in surface atmospheric conditions driven mainly by the Southern Ocean. Therefore, in this present study, we apply a polar regional climate model called NHM-SMAP, which was originally developed for the Greenland ice sheet (Niwano et al., 2018, 2019, 2021; Fettweis et al., 2020), in Antarctica and analyze its simulation results from 1991 to the present. According to our evaluation of the model in terms of the ice sheet surface mass balance during the study period, mean error and root mean square error are –12.2 mm year^–1 and 139.8 mm year^–1, respectively, which are better than those obtained in the Greenland ice sheet (Niwano et al., 2018; Fettweis et al., 2020). Therefore, in this contribution, we focus mainly on surface atmospheric and snow/ice physical conditions relevant to the ice sheet surface mass balance, and present comprehensive model performance/characteristics.

References:
Fettweis, X., Hofer, S., Krebs-Kanzow, U., Amory, C., Aoki, T., Berends, C. J., Born, A., Box, J. E., Delhasse, A., Fujita, K., Gierz, P., Goelzer, H., Hanna, E., Hashimoto, A., Huybrechts, P., Kapsch, M.-L., King, M. D., Kittel, C., Lang, C., Langen, P. L., Lenaerts, J. T. M., Liston, G. E., Lohmann, G., Mernild, S. H., Mikolajewicz, U., Modali, K., Mottram, R. H., Niwano, M., Noël, B., Ryan, J. C., Smith, A., Streffing, J., Tedesco, M., van de Berg, W. J., van den Broeke, M., van de Wal, R. S. W., van Kampenhout, L., Wilton, D., Wouters, B., Ziemen, F., and Zolles, T. (2020): GrSMBMIP: intercomparison of the modelled 1980–2012 surface mass balance over the Greenland Ice Sheet. The Cryosphere, 14, 3935–3958, https://doi.org/10.5194/tc-14-3935-2020.

Niwano, M., Aoki, T., Hashimoto, A., Matoba, S., Yamaguchi, S., Tanikawa, T., Fujita, K., Tsushima, A., Iizuka, Y., Shimada, R., and Hori, M. (2018): NHM–SMAP: spatially and temporally high-resolution nonhydrostatic atmospheric model coupled with detailed snow process model for Greenland Ice Sheet. The Cryosphere, 12, 635-655. https://doi.org/10.5194/tc-12-635-2018.

Niwano, M., Hashimoto, A., and Aoki, T. (2019): Cloud-driven modulations of Greenland ice sheet surface melt. Sci. Rep., 9, 10380, https://doi.org/10.1038/s41598-019-46152-5.

Niwano, M., Box, J. E., Wehrlé, A., Vandecrux, B., Colgan, W. T., and Cappelen, J. (2021): Rainfall on the Greenland ice sheet: present-day climatology from a high-resolution non-hydrostatic polar regional climate model. Geophys. Res. Lett., 48, e2021GL092942. https://doi.org/10.1029/2021GL092942.