Assessing recent trends in high-latitude Southern Hemisphere surface climate

• Published in: Nature Climate Change
• Main Authors: Jones, JM, Gille, ST, Goosse, H, Abram, NJ, Canziani, PO, Charman, DJ, Clem, KR, Crosta, X, De Lavergne, C, Eisenman, I, England, MH, Fogt, RL, Frankcombe, LM, Marshall, GJ, Masson-Delmotte, V, Morrison, AK, Orsi, AJ, Raphael, MN, Renwick, JA, Schneider, DP, Simpkins, GR, Steig, EJ, Stenni, B, Swingedouw, D, Vance, TR
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Publishing Group 2016
• Subjects: Antarc*; Antarctic; Antarctica; Greenland; Sea ice
• Online Access: http://hdl.handle.net/10871/24938; https://doi.org/10.1038/nclimate3103

Understanding the causes of recent climatic trends and variability in the high-latitude Southern Hemisphere is hampered by a short instrumental record. Here, we analyse recent atmosphere, surface ocean and sea-ice observations in this region and assess their trends in the context of palaeoclimate records and climate model simulations. Over the 36-year satellite era, significant linear trends in annual mean sea-ice extent, surface temperature and sea-level pressure are superimposed on large interannual to decadal variability. Most observed trends, however, are not unusual when compared with Antarctic palaeoclimate records of the past two centuries. With the exception of the positive trend in the Southern Annular Mode, climate model simulations that include anthropogenic forcing are not compatible with the observed trends. This suggests that natural variability overwhelms the forced response in the observations, but the models may not fully represent this natural variability or may overestimate the magnitude of the forced response. Support was provided by the following organizations: N.J.A: QEII fellowship and Discovery Project awarded by the Australian Research Council (ARC DP110101161 and DP140102059); M.H.E., ARC Laureate Fellowship (FL100100214); V.M.D., Agence Nationale de la Recherche, project ANR-14-CE01-0001 (ASUMA), and logistical support to French Antarctic studies from the Institut Polaire Paul-Emile Victor (IPEV); B.S., PAGES Antarctica 2k and the ESF-PolarClimate HOLOCLIP project; H.G., the Fonds National de la Recherche Scientifique (F.R.S.-FNRS-Belgium), where he is Research Director; P.O.C., research grant ANPCyT PICT2012 2927; R.L.F., NSF grant 1341621; E.J.S., the Leverhulme Trust; S.T.G., NSF grants OCE-1234473 and PLR-1425989; D.P.S., NSF grant 1235231; NCAR is sponsored by the National Science Foundation (NSF); G.R.S., NSF grants AGS-1206120 and AGS-1407360; D.S., the French ANR CEPS project Green Greenland (ANR-10-CEPL-0008); G.J.M., UK Natural Environment Research Council (NERC) through ...