EGU2020-11083, updated on 10 Jan 2024
https://doi.org/10.5194/egusphere-egu2020-11083
EGU General Assembly 2020
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

North Atlantic decadal variability in a coupled global model and relevance to observations

Yochanan Kushnir1, Dog Run (Donna) Lee2, and Mingfang Ting1
Yochanan Kushnir et al.
  • 1LDEO-Columbia University, Columbia University, Lamont-Doherty Earth Observatory, Palisades, United States of America (kushnir@ldeo.columbia.edu)
  • 2Dept. of Marine Environmental Sciences ChungNam National University, DaeJeon, Korea (dlee@cnu.ac.kr)

This study focuses on the decadal time scale variability of the North Atlantic Ocean-Atmosphere system. This time scale is relevant to preparedness and adaptation as society becomes increasingly threatened by the adverse impact of anthropogenic climate change. North Atlantic decadal climate variability has been related to interaction between the subpolar and subtropical gyre and manifested in persistent multi-year SST and heat content anomalies and shifts in the latitude of the Gulf Stream/North Atlantic Current (GS/NAC). We apply a space-time analysis to annual, North Atlantic, upper ocean heat content (OHC) anomalies from the National Center for Atmospheric Research (NCAR), Community Earth System Model (CESM) long pre-industrial control run. The analysis reveals decadal anomalies associated with two patterns: a dipole centered on the GS/NAC, in the western side of the Basin that oscillates quasi-regularly, reversing its sign every of 6 to 7 years. The second pattern is centered in the eastern side of the basin and lags the first by about 5 years, implying that heat is transported between the subtropical and subpolar gyres. Analysis of surface windstress anomalies connected with these OHC fluctuations implies that the latter are forced by stochastic atmospheric variability. Further analysis compares the model patterns with observations to determine their relevance and predictability and assesses their response to climate change.

How to cite: Kushnir, Y., Lee, D. R. (., and Ting, M.: North Atlantic decadal variability in a coupled global model and relevance to observations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11083, https://doi.org/10.5194/egusphere-egu2020-11083, 2020.

Displays

Display file