Recent Rapid Decline of the Arctic Winter Sea Ice in the Barents–Kara Seas Owing to Combined Effects of the Ural Blocking and SST
- 14 Downloads
This study investigates why the Arctic winter sea ice loss over the Barents–Kara Seas (BKS) is accelerated in the recent decade. We first divide 1979–2013 into two time periods: 1979–2000 (P1) and 2001–13 (P2), with a focus on P2 and the difference between P1 and P2. The results show that during P2, the rapid decline of the sea ice over the BKS is related not only to the high sea surface temperature (SST) over the BKS, but also to the increased frequency, duration, and quasi-stationarity of the Ural blocking (UB) events. Observational analysis reveals that during P2, the UB tends to become quasi stationary and its frequency tends to increase due to the weakening (strengthening) of zonal winds over the Eurasia (North Atlantic) when the surface air temperature (SAT) anomaly over the BKS is positive probably because of the high SST. Strong downward infrared (IR) radiation is seen to occur together with the quasi-stationary and persistent UB because of the accumulation of more water vapor over the BKS. Such downward IR favors the sea ice decline over the BKS, although the high SST over the BKS plays a major role. But for P1, the UB becomes westward traveling due to the opposite distribution of zonal winds relative to P2, resulting in weak downward IR over the BKS. This may lead to a weak decline of the sea ice over the BKS. Thus, it is likely that the rapid decline of the sea ice over the BKS during P2 is attributed to the joint effects of the high SST over the BKS and the quasi-stationary and long-lived UB events.
Key wordsArctic sea ice rapid decline Ural blocking quasi stationary sea surface temperature (SST)
Unable to display preview. Download preview PDF.
The authors thank the three anonymous reviewers for their helpful comments in improving this paper.
- Cavalieri, D. J., C. L. Parkinson, P. Gloersen, et al., 1996: Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS Passive Microwave Data, Version 1 (updated yearly). Boulder, CO, USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. Accessed on 6 November 2017. doi: 10.5067/8GQ8LZQVL0VL.Google Scholar
- Luo, D. H., 2005: A barotropic envelope Rossby soliton model for block–eddy interaction. Part I: Effect of topography. J. Atmos. Sci., 62, 5–21, doi: 10.1175/1186.1.Google Scholar
- Luo, D. H., A. R. Lupo, and H. Wan, 2007: Dynamics of eddydriven low-frequency dipole modes. Part I: A simple model of North Atlantic Oscillations. J. Atmos. Sci., 64, 3–28, doi: 10.1175/JAS3818.1.Google Scholar
- Luo, D. H., Y. Q. Xiao, Y. Yao, et al., 2016a: Impact of Ural blocking on winter warm Arctic–cold Eurasian anomalies. Part I: Blocking-induced amplification. J. Climate, 29, 3925–3947, doi: 10.1175/JCLI-D-15-0611.1.Google Scholar
- Luo, D. H., Y. Q. Xiao, Y. N. Diao, et al., 2016b: Impact of Ural blocking on winter warm Arctic–cold Eurasian anomalies. Part II: The link to the North Atlantic Oscillation. J. Climate, 29, 3949–3971, doi: 10.1175/JCLI-D-15-0612.1.Google Scholar
- Wu, B. Y., R. H. Huang, and D. Y. Gao, 2002: Numerical simulations on influences of variation of sea ice thickness and extent on atmospheric circulation. J. Meteor. Res., 16, 150–164.Google Scholar