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Global Tide and Surge Reanalysis (GTSR) dataset
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Description
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GTSR (Global Tide and Surge Reanalysis) is the first global reanalysis of storm surges and extreme sea-levels based on hydrodynamic modelling. GTSR covers the entire world's coastline and provides estimates of extreme sea-levels values based on the period 1979-2014. The dataset is based on the application of two global hydrodynamic models: GTSM to simulate storm surges [Verlaan et al., 2015], and FES2012 to simulate tides [Carrere et al. 2012]. Surge levels were modelled by forcing GTSM with with 10 m wind speed and atmospheric pressure from the ERA-Interim climate reanalysis [Dee et al., 2011]. Total water levels are calculated by superimposing tides and surges.  The 1-in-100 year sea level was estimated by fitting a Gumbel extreme value distribution to the annual maxima. Validation shows that there is very good agreement between modelled and observed sea-levels, and that the performance of GTSR is similar to that of regional hydrodynamic models. Due to the limited resolution of the meteorological forcing, extremes are slightly underestimated. This particularly affects, especially in regions affected by tropical cyclones, which requires further research. The GTSR dataset can be applied for assessing flood risk and impacts of climate change. See Muis et al. [2016] for further details. By using the GTSR dataset you agree to cite Muis et al. [2015] in publications that make use of the dataset.

File details
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The global map of the 1-in-100 year sea level are provided in a polyline shapefile format. The  water levels are based over 12,000 locations along the coastline based on the centroids of the DIVA segments database. The coastal segments have a variable length depending on administrative units and socio-economic characteristics. For details on the coastal segmentation see Vafeidis et al. [2008]. 

The identifier of each locations in given in the attribute STATION. The LATI and LONGI attributes refer to the coordinates of the centroid of the coastal segment based on the WGS84 projection. LENGTH shows the length of the coastal segment in km. RP100 refers the water level with a return period of 1-in-100 years in [m]. 

References
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Carrre et al. FES 2012: A new global tidal model taking advantage of nearly 20 years of altimetry. in Proceedings of 20YPRA symposium 38 (2012).

Dee et al. (2011) The ERA-Interim reanalysis: configuration and performance of the data assimilation system. Q. J. R. Meteorol. Soc. 137, 553597.

Muis et al. (2016) A global reanalysis of storm surges and extreme sea levels. Nature Communications. doi: 10.1038/NCOMMS11969

Verlaan et al. (2015)GLOSSIS: Global Storm Surge Forecasting and Information System. in Australasian Coasts & Ports Conference 2015 16.

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For further information or questions please contact Sanne Muis (IVM-VU) by e-mail (sanne.muis@vu.nl)