A 44-year hindcast of wind wave fields over the Baltic Sea

doi:10.1016/j.coastaleng.2008.02.017

Coastal Engineering

Volume 55, Issue 11, November 2008, Pages 894-905

https://doi.org/10.1016/j.coastaleng.2008.02.017 Get rights and content

Abstract

This study presents wind wave fields' characteristics over the Baltic Sea obtained with the WAM model and their verification against observations. This is a part of the HIPOCAS research project funded by the European Union with an objective to obtain a 44-year hindcast of wind, wave, sea-level, and current climatology for European waters and coastal seas for application in coastal and environmental decision processes. A reasonable agreement between the modelled and observed both in-situ and satellite wave data was obtained. A high-resolution homogeneous wave data set generated with the hindcast system created within HIPOCAS provided a large number of possibilities to examine the long-term statistics and variability of the wind wave fields over the Baltic Sea.

Introduction

Information requirements for modern coastal management and engineering design need a statistical characterisation of the prevailing environmental conditions. The impact of a storm on the shoreline or coastal structure is primarily related to the combined influence of surges, sea surface waves, and currents. Therefore, there is a growing need for long-term statistical information about the meteorological and sea state parameters. HIPOCAS (see Guedes Soares et al., 2002) was an EU-research project originated from this conviction. Its objective was to obtain a multi-decadal hindcast of wind, wave, sea-level, and current parameters for European waters and coastal seas. A high-resolution homogeneous data set was generated in the framework of the project and it covered coastal seas and coastlines of several European countries. A number of statistics essential to almost all marine activities, has been obtained from this data set. Also, the atlas of metocean data was developed in the project. This atlas should be an extremely useful tool for the identification of sensitive and hazardous areas in relation to shipping, construction, and the coastal zone management.

The Institute of Oceanography, University of Gdańsk (IOUG) contributed to the HIPOCAS project by simulating wind-driven current, sea-level and wind wave fields over the Baltic Sea. For current and sea-level modelling the 3D baroclinic Princeton Ocean Model (POM) was used, while wind waves were modelled using the WAM (WAve Model) Cycle 4 (WAMDI Group, 1988, Komen et al., 1994).

This study presents the wind wave hindcast system for the Baltic Sea, as well as its validation. WAM has been setup and validated in many places all over the world, including the Baltic Sea (see e.g. Paplińska, 1999, Paplińska, 2001, Cieślikiewicz and Herman, 2001, Cieślikiewicz and Herman, 2002). However, the modelling time periods for the Baltic Sea have not usually exceeded a few year period. The 44-year hindcast of wave field over the Baltic performed within HIPOCAS has been the first attempt to generate a long-term wave data set for this sea region, using WAM (see Cieślikiewicz et al., 2004). The produced wave database covers the period 1958–2001, and composes a unique opportunity to generate and analyse long-term statistics of wave parameters.

Section snippets

The wave modelling system for the Baltic Sea

The WAM model was set up and run on the Cray X1 computer of the Interdisciplinary Centre of Mathematical and Computational Modelling at Warsaw University (ICM).

Validation of hindcast wave data

The results of wave hindcast for selected periods were compared with both measured buoy data and satellite data. The results of those comparisons are described in the two following sections.

Conclusions

Comparison between the modelled and observed time series of wave field parameters over the Baltic Sea, performed within HIPOCAS, presents a sufficiently good agreement to prove effectiveness of the wind wave hindcast system set up and exploited within the project. This system is based on the WAM model. Although quite a good agreement between the hindcast data and measurements was obtained, some tendency of the model to overestimate significant wave height during storm peaks has been noticed.

Acknowledgements

This study was carried out as a part of the FP5 HIPOCAS project funded by the Commission of the European Union under contract EVK2-1999-00038. The authors acknowledge cooperation with the eight HIPOCAS partners from eight different European countries: Technical University of Lisbon (IST), University College Cork (UCC), Forschungszentrum Geesthacht GmbH (GKSS), Ente Público Puertos del Estado, (EPPE), MétéoMer, Euro-Mediterranean Centre on Insular Coastal Dynamics of the University of Malta

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Citation Excerpt :
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A 44-year hindcast of wind wave fields over the Baltic Sea

Abstract

Introduction

Section snippets

The wave modelling system for the Baltic Sea

Validation of hindcast wave data

Conclusions

Acknowledgements

Wind wave modelling over the Baltic Sea and the Gulf of Gdańsk

Inzç. Mor. Geotech.

Wave and current modelling over the Baltic Sea

Multi-decadal wind wave modelling over the Baltic Sea

A 40-years hindcast of wind, sea level and waves in European waters

Multi-decadal atmospheric modelling for Europe yields multi-purpose data

Eos

Sensitivity studies with the regional climate model REMO

Meteorol. Atmos. Phys.

A user's guide for SCRIP: a Spherical Coordinate Remapping and Interpolation Package—Version 1.4

Theoretical Division Los Alamos National Laboratory

First- and second-order conservative remapping schemes for grids in spherical coordinates

Mon. Weather Rev.