CONCEPTS Regional Ocean Forecast System Development

Transcription

1 CONCEPTS Regional Ocean Forecast System Development Fraser Davidson DFO, NAFC G. Smith, Y. Lu, D. Dumont, B. Tremblay, J-F Lemieux, H. Ritchie, F Roy,Y Liu, F Dupont,, C Beaudoin, Mathieu Chevalier, G Garric, C-E Testut, P Pellerin and the rest of the CONCEPTS Team Meteorological Research Division, Environment Canada Meteorological Service of Canada, Environment Canada Science Branch, Department of Fisheries and Oceans Canada Mercator-Océan, Toulouse, France

2 Canada requires regional ice-ocean-atmosphere forecasts and information services for: Improvements to regional/global weather forecasts days/seasons are expected. Canadian Ice Service & Canadian Coast Guard Ice Operations Fisheries and aquaculture management Interpreting biological observations Regional climate change impacts Risk assessments for extreme events Emergency response: Search and Rescue, dispersion of pollutants Offshore Oil and Gas Industry. Fog prediction, Pack Ice and Iceberg Management, Deep Water Riser Vibration Prediction, Site planning, Deep well blow outs

3 Outline Overall Goal From RIPS to RIOPS RIOPS Tuning (ice ocean model) Validation Atmospheric coupling and high res winds Ice model improvements Downscalling Summary/COSS Themes/Outlook

4 METAREA Integrated Marine Prediction System Coupled atmosphere-ice-oceanwave-snow model GEM (15km) NEMO-CICE-WW3 (3-8km) Tides, semi-lagrangian scheme, JFNK solver for CICE, wave-ice coupling 3-5 day ensemble forecasts Expected implementation: March km GEM REPS CREG12

5 Regional Ice Prediction System (RIPS) 5km North American grid 3DVar Ice analysis SSMI, SSMIS, ASCAT CIS daily charts, image analyses, lake analyses CICE4.1 Ice model Forced by CMC RDPS 48hr forecasts at: 0Z, 6Z, 18Z, 24Z Running at CMC spring 2013

6 Regional Ice Prediction System Description

7 Evaluation of Sea Ice Forecasts Comparison with IMS Analyses: Interactive Multisensor Snow and Ice Mapping System (NOAA-NIC) Daily Northern Hemisphere ice analyses on 4km grid (ice/water) Assimilates : AVHRR, GOES, SSM/I Evaluation Methodology: Interpolate model forecasts to IMS grid Calculate contingency table values using 0.4 ice concentration cutoff IMS Bin results on 1 lat-lon grid Forecast Ice Ice Hit ice Forecast Miss GODAE OceanView Symposium, Hilton Baltimore, 4-6 No November ice 2013 IMS No ice False Alarm Hit water

8 Evaluation of Sea Ice Forecasts Daily forecasts for 2010, 48hr lead time A perfect forecast would have PCT=1 and Bias=1 RIPS shows better statistics than persistence Esp. In summer and fall Over most of domain Better Worse Better Worse

9 Calibration of ice strength (P*) Lemieux et al. (QJRMS, submitted) Evaluation of ice drift against Arctic Buoys (IABP) Forecasts from 5km Regional Ice Prediction System (RIPS) CICE stand-alone, daily 48hr forecasts at 00Z, 06Z, 12Z, 18Z Optimize P* (Hibler, 1979): Best value: ~12.5 kn/m 2 Tuning compensates errors in thickness

10 Calibration of ice strength (P*) Lemieux et al. (QJRMS, submitted) Evaluation of ice drift against Arctic Buoys (IABP) Optimized P* gives best representation of stoppage Free drift events P* = 0 Nm -2 stoppage events Optimal parameter Rigid ice P* = Nm - 2 P* = Nm - 2

11 Evaluation of Sea Ice Forecasts Only evaluate points where the 3DVAR analysis changes by more than 10% Focus on ice edge and areas of confidence in analysis RIPS has lower RMS than persistence for all months Daily 48hr forecasts for 2010

12 Regional Ice-Ocean Prediction System Couple RIPS to NEMO 3-8km Arctic/N.Atl configuration (CREG12) SAM2 ocean assimilation (SEEK) with 3DVar ice assimilation Expected experimental implementation for March 2014 Analysis provided by GIOPS SAM2 + ice/sst assim RIOPS Analysis 2015

13 Regional Ice-Ocean Prediction System Domains ORCA grid favours higher resolution in the Canadian Arctic Archipelago configuration (CREG12) SAM2 ocean assimilation (SEEK) with 3DVar ice assimilation Expected experimental implementation for March 2014

14 Model Tuning, Improvements Successive Hindcast Experiments

15 Validation: Sea ice Summer 2005 ice concentration comparison using the Global Ocean Sea Ice Concentration Time Series (EUMETSAT), illustrating the accumulation of model ice in the southern Beaufort Sea. However total sea ice extent is reasonably compared with the satellite radiometer record

16 Validation: Sea ice Thickness estimates for Feb/Mar 2006 from IceSat data (Kwok et al., 2009) and the model. This shows that the model displaces the thick ice toward the southern Beaufort & Chukchi Seas. Model comparison with a moored ULS in the Beaufort Gyre, using ice thickness category distribution, also shows the model ice to be too thick. GODAE OceanView Thickness Symposium, (m) Hilton Baltimore, 4-6 November 2013

17 Tides Largest tides in world Ungava Bay Uncertainty in bottom topography in some areas Hudson Straight, Fox Basin

18 Lack of good bathymetry observations Hudson Bay/straight + Fox Basin NABD NABD ETOPO1

19 Improve M2 Tide Solution by Refining Bathymetry Diff in M2 magnitude CREG12 solution (T1)

20 CREG12 Hindcast 6 CREG12-CICE with tides NEMO CONCEPTS_ CICE4.0 ice volume issue

21 Validation: Sea surface height Mean dynamic topography from satellite altimetry (Farrell et al, 2012) Mean sea surface height from model CREG12-H5 shows good agreement on large scale features e.g. the Beaufort Gyre.

22 Validation: Temperature Mean temperature profiles from moored profilers show the model misses the warm Pacific layer (~60m) in the central Beaufort Sea but not on the shelf. Comparison of model temperatures with CTD measurements at ~60m shows this cold bias extends across the deep Beaufort Sea.

23 Impact of A-O-I Coupling for Beaufort Sea 10 Day Forecasts Coupled uncoupled forecast differences for Difference in ice fraction Difference in 2m temperature GEM 33km coupled to NEMO-LIM 1/4 (15km)

24 Impact of atmospheric resolution on coastal locations 15 km wind resolution 2.5 km wind resolution

25 Impact of atmospheric resolution on wind strength near land 2.5 km wind resolution vs 15 km wind resolution

26 Ice Model Improvements Improved Ice Models for Forecast and Analysis system Large computers Better modelling of ice stresses Improving ice lead forecast prediction in Beaufort Important for coupling with Atmospheric Forecasts

27 Landfast Ice Variability Beaufort Sea

28 Landfast Sea Ice Variability Shelagsk Cape

29 Detecting Marginal Ice zone form of ice (FA) variable of the egg code is a valid prospect for assessing wave-ice interactions. discriminate MIZ polygons from digital ice charts. Selected polygons are connected along the ice edge and the average width of the MIZ is calculated from the skeleton obtained from thinning operations

30 Exchange between wave and ice model Determining flow bloc size and width of Marginal Ice Zone Adding information on Marginal Ice Zone

31 New Data Set Canadian Ranger Ocean Watch Program (CROW) Field Program Feb-March 2013 Initially for climate monitoring Adapting to real time data contribution to ocean-ice prediction system

32 Ice Buoys and SVP

33 Towards Pan Canadian 1/36 Regional model Downscaling project for building 1/36 regional zoom funded by oil industry (1.4 M$) Experimental implementation in operations CREG36 East (2015): CREG36 Pan Canadian ~2018

34 Drifter mean surface speed Comparison of 2-year Run results with CREG 1/12 Hincast5 and Drifters CREG 1/12 (2003 annual mean surface currents) NFS 1/36 (2003 mean surface currents)

35 Summary Regional Ice Prediction System currently running in CMC Operations producing 48hr forecasts 4 times/day at 5km resolution around North America Adding in Ocean Prediction (2014) Coupling between Atmosphere, Ice and Ocean important in North Ice and ocean model improvements ongoing Team work, funded projects and strong collaboration with MERCATOR-OCEAN contribute contribute to this team outcome. Collaboration with MERCATOR-OCEAN Important

36 COSS THEMES Lecce Workshop Themes Advances in integrated coastal observations Advances in downscaling Exchanging information and identifying good practices Puerto Rico workshop (Jan 2014) (THEMES) Predictability in the coastal oceans Upper-ocean processes, waves-current-atmosphere interactions and couplings Probabilistic approaches and risk assessment in the COSS, science in support of the mitigation of coastal hazards Impact and signature of climate change in the coastal oceans Training/Education/Outreach initiatives in the coastal oceans

37 CONCEPTS Outlook More Canadian Participation in COSS RIOPS Forecast System Experimental (2014) RIOPS Analysis System Experimental (2015) RIOPS-REPS Coupled Ensemble Forecasts (2015) CREG36 East (2015) CREG36 Pan Canadian ~2018 Further down scaling with FVCOM in targeted domains starting now.