1 / 23

Winter sea ice variability in the Barents Sea

Winter sea ice variability in the Barents Sea. C. Herbaut , M.-N. Houssais et A.-C. Blaizot LOCEAN, UPMC. Barents Sea. Sea ice extent. Surface circulation. Motivation

asa
Download Presentation

Winter sea ice variability in the Barents Sea

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Winter seaicevariability in the Barents Sea C. Herbaut, M.-N. Houssais et A.-C. Blaizot LOCEAN, UPMC

  2. Barents Sea Sea ice extent Surface circulation

  3. Motivation Winter sea ice in the Barents Sea impacts on climate of Northern Europe (Yang and Christensen 2012, Petoukhov et Semenov, 2010, Outten and Esau, 2011, ...) January SAT - Sea ice concentration correlation map 1st SVD mode Outten and Esau, 2011

  4. Mechanisms of winter Barents Sea sea ice area variability Surface wind (Pavlova and Pavlov, 2013). SLP (2007) Pavlova et al., 2013 Southerly wind anomaly  Reduced sea ice extent

  5. Mechanisms of winter Barents Sea sea ice area variability Atlantic Water transport (Arthun et al. 2012, Schlichtholz, 2011) Surface wind (Pavlova and Pavlov, 2013). SLP (2007) BSO Heat Transport Barents Sea Ice Area Arthun et al. , 2012 Pavlova et al., 2013 Increasedheat transport  decreasedseaice area (+ 2 years) Southerly wind anomaly  Reduced sea ice extent

  6. Winter SeaIce Concentration (SSMR - SSM-I) Two modes of interannualvariability : Northern mode and Eastern mode Std (1979-2011) 1979 2006

  7. Winter SeaIce Concentration (SSMR - SSM-I) Two modes of interannualvariability : Northern mode and Eastern mode Std (1979-2011) 1979 Seaice area R= 0.38 2006 Northern Mode Eastern Mode

  8. Seaice area Northern and Eastern SIC modes Regression of SIC on Northern Mode Index Regression of SIC on Eastern Mode Index Northern Mode Eastern Mode  Two distinct spatial patterns

  9. Impact of surface wind ERA-Interimwinter (JFM) 10-m wind (1979-2011) Lag 0 Lag -1 year Regression on the Northern Mode Index

  10. Impact of surface wind ERA-Interimwinter (JFM) 10-m wind (1979-2011) Lag 0 Lag -1 year Regression on the Northern Mode Index Min=-0.7 Min=-0.6 Correlation with meridional wind  Northern SIC mode associated with northerlywinds

  11. ERA-Interimwinter (JFM) 10-m wind (1979-2011) Regression on the Eastern Mode Index Correlation with zonal wind Lag 0 Lag 0 Min=-0.7 Eastern SIC mode associated with easterlywinds  Surface windexplainsonly 50% of the SIC variance : other forcings ?

  12. Ice-ocean interactions in an ice-ocean model Model ORCA025 Arctic-Atlantic configuration, ERA-I forcing (1979-2011) SIC Std Seaice area R> 0.9 Observations Northern Mode Eastern Mode SIC Std ___ ---- Model Observations  Same patterns of variability but weaker variance in the model

  13. Winter (JFM) seaice drift Climatology 1979-2011

  14. Winter (JFM) seaice drift Regression on the Northern Mode Index Regression on the Eastern Mode Index Climatology 1979-2011 Eastern Mode : significantwestward drift anomalies

  15. Winter (JFM) ice production Regression on the Eastern Mode Index Climatology 1979-2011 • Large icemelt anomalies (2 mm day-1) at the iceedge : • Eastern mode : response to the eastward expansion of the ice edge

  16. Winter (JFM) ice production Regression on the Northern Mode Index Regression on the Eastern Mode Index Climatology 1979-2011 • Large icemelt anomalies (2 mm day-1) at the iceedge : • Eastern mode : response to the eastward expansion of the iceedge • Northern mode : response to the oceanheat advection ?

  17. Atlantic Water circulation Oceantemperature at 110 m Oceancurrentsat 110 m • Two branches of Atlantic Water: • Northern branch : less intense

  18. Heat transport through the western Barents Sea (BSO) CorrelationwithSeaIce Area modes Northern Mode Eastern Mode Northern mode :  maximum correlationbetween BSO heat transport anomalies in fall and winter SIC anomalies in northern Barents Sea  no significant correlation atearlier lags Eastern mode:  no correlationwith the heat transport through BSO

  19. Oceancurrent anomalies at 110 m Regression on the Northern Mode Index (Seasonallag) JFM (lag 0) OND • Weakening of the northern branch of Atlantic Water infall • Increasedwinter SIA in northern Barents Sea • No clearlinkbetweenwinterBSO inflow and winter SIA in northern Barents Sea

  20. Heat content in the western Barents Sea CorrelationwithSeaIce Area modes Northern mode :  Maximum correlationatlag 0  Persistencegivessignificantlaggedcorrelationswhenheat content leads by up to 1 year

  21. Oceantemperatureat 110 m Regression on the Northern Mode Index AMJ JFM • Northern mode associated with a contemporary large scale pattern of intemediate temperature anomalies • Part of the winter temperature anomalies originate in previous spring • Wind-driven anomalies (explaining lagged correlation of Northern mode with wind stress ?)

  22. Next What drives the varaibility of each? Advection of temperature anomalies Link with the Atmospheric modes

  23. The research leading to these results has received funding from the European Union 7th Framework Programme (FP7 2007-2013), under grant agreement n.308299 NACLIM www.naclim.eu

More Related