1. Evaluation of Polar Regions in Ocean Reanalyses Status of the ORA-IP and EU-COST EOS projects in the polar oceans
Keith Haines , University of Reading
Contributions from Petteri Uotila, Matthieu Chevallier, Hugues Goosse and many others
GOW workshop
10-14 October 2016 – Toulouse - France

2. Outline The Ocean Reanalysis Intercomparison Project
The ORA-IP Community
What has been achieved
The ORA-IP Data Repository
The EOS COST Project for The Polar oceans:
Ambitions for the project
Arctic issues
Antarctic issues
Preliminary Results
Arctic Sea ice (Results in Chevallier et al. 2016)
Arctic Ocean Heat and Salt Content
Arctic Hydrography (Stratification, T:S relations)
Arctic Freshwater Content
Antarctic Ocean Heat and Salt Content
Antarctic Sea Ice
Summary and Further Plans

3. CLIVAR GSOP/GODAE Ocean View Ocean Reanalysis Inter-comparison (ORA-IP)
Magdalena Alonso Balmaseda (ECMWF)
Takahiro Toyoda (MRI-JMA)
Maria Valdivieso (UoReading)
Andrea Storto (CMCC)
Gregory Smith (Environment Canada)
Matthew Palmer (UK MetOffice)
Fabrice Hernandez (Mercator Ocean)
Li Shi (BMRC)
Keith Haines (UoReading)
Matthieu Chevallier (CNRS)
Tony Lee (JPL)
Yosuke Fujii (MRI-JMA)
Kirsten Wilmer-Becker (MetOffice)
And All Reanalysis Providers
AMOC NCAR
MyOcean ¼ degree CMCC
6 Observation only products
13 Low resolution models
8 High resolution models (1/3 or ¼ degree)
4 Coupled DA products
6 Long reanalyses, starting 1950’s
Summary Paper
Balmaseda, M.A. et al., The Ocean Reanalysis Intercomparison project (ORA-IP) J.Op.Oceanogr. 2015
Special Issue Climate Dynamics:
9 papers published online in 2015
Only Arctic Sea Ice paper explicitly focussed on High Latitudes

4. Remon Sadikni
The ORA-IP Data Server

7. Ocean Heat Content from ORA-IP
Palmer et al 2016

9. Polar ORA-IP Polar ORA-IP
Petteri Uotila, Marika Marnela, Meri Korhonen (FMI Fi); Antoine Barthélemy, François Massonnet, Hugues Goosse (UC Louvain); Gilles Garric, Marie Drevillon (Mercator); Matthieu Chevallier (Meteo France); Lien Vidar (IMR) Jiping Xie (NERSC No); Dorotea Iovino, Verena Haid (CMCC IT); Frank Kauker (AWI De); Drew Peterson, (UKMO), Keith Haines (UoR UK), Steffen Tietsche (ECMWF); Li Shi (BoM Au), Neven Fuckar (BSC Sp)
Make regional Arctic and Antarctic ORA comparisons
More regional expertise (comparisons not done by reanalysis experts)
Establish accessibility of ORA data repository
Availability of ORA data on standard grid (Levitus 1°x1°) in standard format cf-netcdf
Benefit from existing data
OHC, OSC, Mixed layer depths, Sea Ice, Surface fluxes
Updating for most recent ORA products
New variables
eg. Hydrography, Currents, Strait Transports……..
Work in progress: Meetings March 2016, Nov FMI
Immediate Aims at 2 Papers : Arctic and Antarctic

10. Polar ORA-IP Some Polar Issues
Atlantic water pathways; Fram strait and Arctic boundary currents
Beaufort gyre freshwater storage variations
Heat and Freshwater mean budgets/trends/transports for Arctic
Sea Ice seasonal cycle and trends in Arctic
Arctic halocline maintenance and variability
Antarctic sea ice, mean and trends
Mixed layer variability around ACC
ACC transports
OHC trends around Antarctic continent

11. ORA-IP : Arctic sea ice In Climate Dynamics Special Issue …
First-time ever systematic intercomparison of Arctic sea ice fields from global ORA…
Benefits from recent intercomparisons of observational datasets :
Ivanova et al., 2014, 2015 (SIC);
Zygmuntowska et al., 2014 (SIT);
Sumata et al., 2014 (velocity)

12. Sea ice concentration/areas/extent
Chevallier et al 2016
Sea ice extent (Mkm2)
September
Figures avec les biais pour illustrer la difficulté liée à la calibration du système, et la solution intermédiaire consistant à prendre les sous-bassins.

13. Sea ice thickness Mean sea ice thickness (m) Difference wrt ICESAT
Average March
Figures avec les biais pour illustrer la difficulté liée à la calibration du système, et la solution intermédiaire consistant à prendre les sous-bassins.

14. What about sea ice predictions?
Statistical forecasts:
ORA used to fit regression models using non-observed quantities (cf PIOMAS)
Lagged correlations : Sea ice volume ➙ Sea ice extent (same period)
Predictor : Sea ice Volume
Figures avec les biais pour illustrer la difficulté liée à la calibration du système, et la solution intermédiaire consistant à prendre les sous-bassins.
Predictand : Sea ice Extent
Will result in very different statistical forecasts
What is the truth?
Possible collaboration with SIPN?

15. Observation only products
Mean Arctic Ocean Heat Content
Anomalies ( )
Haines
Mignac
Observation only products
(0 – 300m)

16. Observation only products
Mean Arctic Ocean Salt Content
Anomalies ( )
Observation only products
(0 – 300m)

17. Hydrography comparisons
Uotila
Stratification and T-S 3 sites
Amerasian basin (80N 215E)
Central Arctic (88N 10E)
Nansen basin (84N 100E)
Layer averages for 5 layers available
0-100, , ,
, m depth
Layer trend analyses also underway

18. Liquid freshwater content (m) in the Arctic Ocean averaged from 1993 to 2010
The reference salinity is 34.8 and the integration in the vertical is taken from surface to the depth where salinity is equal to the reference salinity.
3D salinity fields available from CGLORSv5, GLOSEA_GO1, GLOSEA_GO5, MOVEG2, MOVE-G2i, ORAP5, TOPAZ4
Iovino

19. Observation only products
Mean Antarctic Ocean Heat Content
Anomalies ( )
Observation only products
(0 – 700m)

20. Observation only products
Mean Antarctic Ocean Salt Content
Anomalies ( )
Observation only products
(0 – 700m)

21. Consistency with Antarctic sea ice thickness measurements from ASPeCt
Massonnet
Ship SIT data
Obs
Evaluation conducted on (longest common period between reanalyses and ASPeCt data).
Label
Institution
Compatibility index
Mean abs error (cm)
GloSea5
UK Met Office
0.44 13
GECCO2
U. Hamburg
0.28 22
ECDA
GFDL
0.48
GLORYSv1
MERCATOR
0.42
GLORYSv3
0.43
C-GLORS
CMCC
0.49
ECCO
NASA 12
Ship SIT data
regridded to 1° bins
Reanalysis data
sampled monthly
Consistency assessed
against bins
with 4+ SIT Obs
None show >50% “compatibility”
(ORA within ASPeCt SIT range with 4+ Obs)

22. Summary and Further Work
The ORA-IP Data Repository is well established and accessible for new projects
Polar ORA-IP should submit Arctic and Antarctic summary papers by early 2017
New studies likely to be needed
Ocean Heat and Freshwater transports currently not widely available from ORA
Polar regions may provide strong constraints on Earths Energy and water budget analyses
Polar Climate change trends very large
Align Polar Metrics with Operational community « State of the Oceans »

23. Sea ice volume Annually-averaged Arctic sea ice volume (103 km3)
Figures avec les biais pour illustrer la difficulté liée à la calibration du système, et la solution intermédiaire consistant à prendre les sous-bassins.

24. Sea ice thickness Arctic sea ice volume (ICESat domain)
Comparison with ICESat and CryoSAT
Figures avec les biais pour illustrer la difficulté liée à la calibration du système, et la solution intermédiaire consistant à prendre les sous-bassins.

25. Sea ice velocity Arctic mean sea ice velocity: Annual mean
Seasonal cycle
Ice export through Fram Strait (annual mean)
Figures avec les biais pour illustrer la difficulté liée à la calibration du système, et la solution intermédiaire consistant à prendre les sous-bassins.

26. Feb-Mar
Kauker

27. Oct-Nov