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Constraining Energetic Slope Currents Through Assimilation of High-frequency Radar Observations : Volume 11, Issue 2 (11/03/2015)

By Sperrevik, A. K.

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Book Id: WPLBN0004020250
Format Type: PDF Article :
File Size: Pages 13
Reproduction Date: 2015

Title: Constraining Energetic Slope Currents Through Assimilation of High-frequency Radar Observations : Volume 11, Issue 2 (11/03/2015)  
Author: Sperrevik, A. K.
Volume: Vol. 11, Issue 2
Language: English
Subject: Science, Ocean, Science
Collections: Periodicals: Journal and Magazine Collection (Contemporary), Copernicus GmbH
Historic
Publication Date:
2015
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications

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Röhrs, J., Christensen, K. H., & Sperrevik, A. K. (2015). Constraining Energetic Slope Currents Through Assimilation of High-frequency Radar Observations : Volume 11, Issue 2 (11/03/2015). Retrieved from http://worldlibrary.net/


Description
Description: Norwegian Meteorological Institute, Oslo, Norway. Assimilation of high-frequency (HF) radar current observations and CTD hydrography is performed with the 4D-Var analysis scheme implemented in the Regional Ocean Modeling System (ROMS). We consider both an idealized case, with a baroclinic slope current in a periodic channel, and a realistic case for the coast of Vesterålen in northern Norway. In the realistic case, the results of the data assimilation are compared with independent data from acoustic profilers and surface drifters. Best results are obtained when background error correlation scales are small (10 km or less) and when the data assimilation window is short, i.e. about 1 day. Furthermore, we find that the impact of assimilating HF radar currents is generally larger than the impact of CTD hydrography. However, combining the HF radar currents with a few hydrographic profiles gives significantly better results, which demonstrates the importance of complementing surface observations with observations of the vertical structure of the ocean.

Summary
Constraining energetic slope currents through assimilation of high-frequency radar observations

Excerpt
Albretsen, J., Sperrevik, A. K., Staalstrøm, A., Sandvik, A. D., Vikebø, F., and Asplin, L.: NorKyst-800 report no. 1: User manual and technical descriptions, Tech. Rep. 2, Institute of Marine Research, Bergen, Norway, available at: http://www.imr.no/filarkiv/2011/07/fh_2-2011_til_web.pdf/nb-no (last access: 5 March 2015), 2011.; Barrick, D. E., Evans, M. W., and Weber, B. L.: Ocean surface currents mapped by radar, Science, 198, 138–144, 1977.; Barth, A., Alvera-Azcarate, A., and Weisberg, R. H.: Assimilation of high-frequency radar currents in a nested model of the West Florida Shelf, J. Geophys. Res., 113, C08033, doi:10.1029/2007JC004585, 2008.; Blockley, E. W., Martin, M. J., McLaren, A. J., Ryan, A. G., Waters, J., Lea, D. J., Mirouze, I., Peterson, K. A., Sellar, A., and Storkey, D.: Recent development of the Met Office operational ocean forecasting system: an overview and assessment of the new Global FOAM forecasts, Geosci. Model Dev., 7, 2613–2638, doi:10.5194/gmd-7-2613-2014, 2014.; Breivik, Ø. and Saetra, Ø.: Real time assimilation of HF radar currents into a coastal ocean model, J. Marine Syst., 28, 161–182, 2001.; Brassington, G. B., Pugh, T., Spillman, C., Schulz, E., Beggs, H., Schiller, A., and Oke, P. R.: BLUElink> Development of operational oceanography and servicing, J. Res. Pract. Inf. Tech., 39, 151–164, 2007.; Broquet, G., Edwards, C. A., Moore, A. M., Powell, B. S., Veneziani, M., and Doyle, J. D.: Application of 4D-Variational data assimilation to the California Current System, Dynam. Atmos. Oceans, 48, 69–92, 2009.; Chapman, D. C.: Numerical treatment of cross-shelf open boundaries in a barotropic coastal ocean model, J. Phys. Oceanogr., 15, 1060–1075, 1985.; Chapman, R. D., Shay, L. K., Graber, H. C., Edson, J. B., Karachintsev, A., Trump, C. L., and Ross, D. B.: On the accuracy of HF radar surface current measurements: Intercomparisons with ship-based sensors, J. Geophys. Res.-Oceans, 102, 18737–18748, 1997.; Christensen, K. H., Sperrevik, A. K., and Röhrs, J.: The spring 2013 field experiment of the ENI/NOFO HF radar project, Tech. Rep. 25, Norwegian Meteorological Institute, Oslo, Norway, available at: http://met.no/Forskning/Publikasjoner/MET_report/2013/filestore/fieldEXP.pdf (last access: 5 March 2015), 2013.; Courtier, P., Thépaut, J.-N., and Hollingsworth, A.: A strategy for operational implementation of 4D-Var, using an incremental approach, Q. J. Roy. Meteorol. Soc., 120, 1367–1387, 1994.; Davis, R. E.: Drifter observations of coastal surface currents during CODE: The method and descriptive view, J. Geophys. Res., 90, 4741–4755, 1985.; Dimet, F.-X. L. E. and Talagrand, O.: Variational algorithms for analysis and assimilation of meteorological observations: theoretical aspects, Tellus A, 38, 97–110, 1986.; Evensen, G.: The Ensemble Kalman Filter: theoretical formulation and practical implementation, Ocean Dynam., 53, 343–367, 2003.; Flather, R. A.: A tidal model of the north-west European continental shelf, Memoires de la Society Royal des Sciences de Liege, 10, 141–164, 1976.; Fu, L.-L., Christensen, E. J., Yamarone, C. A., Lefebvre, M., Ménard, Y., Dorrer, M., and Escudier, P.: TOPEX/POSEIDON mission overview, J. Geophys. Res., 99, 24369–24381, 1994.; Gurgel, K.-W., Antonischki, G., Essen, H.-H., and Schlick, T.: Wellen Radar (WERA): a new ground-wave HF radar for ocean remote sensing, Coastal Eng., 37, 219–234, 1999.; Gustafsson, N.: Discussion on 4D-Var or EnKF?, Tellus A, 59, 774–777, 2007.; Isachsen, P. E.: Baroclinic instability and eddy tracer transport across sloping bottom topography: How well does a modified Eady model do in primitive equation simulations?, Ocean Mod

 

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