Climate Risk and Vulnerability Assessment (CRVA) for the Port of Heraklion in Greece

Climate change is expected to impact the maritime sector, including the port industry. Ports are on the frontline when it comes to experiencing operational challenges from the increased sea levels and extreme weather conditions, associated with increased infrastructure investments. For instance, rising sea water levels are expected to change the accessibility of channels and increase the need for higher quay walls, while the increased intensity or/and frequency of events, such as fog, high winds, and waves, may increase the frequency of port operation disruptions; but changes are uncertain, and with regional variation.

The present study focuses on the Port of Heraklion, one of the main ports of national importance in the Greek Maritime Network, located in the North side of the island of Crete, and aims at assessing the impacts of climate change on port operations associated with: 

• Changes in mean sea level, storm surges and wave characteristics (i.e. wave height, period, frequency of occurrence).
• Reduced visibility caused by intense precipitation and/or fog.
• Disruption of port operations due to high wind speeds, drainage system induced flooding, as well as river discharges and sediment transfer in the harbor basin.

To assess the effects of climate change on winds we use climate change factors (CCFs) obtained using climate model data at 3-hourly temporal resolution over the Island of Crete (i.e. sub-country level) from EURO-CORDEX ensemble, and more in particular from HIRHAM5 RCM (Regional Climate Model) nested in (downscaled from) EC-EARTH GCM (Global Climate model), for two Representative Concentration Pathways of future emissions: RCP 4.5 for the period 2071-2100 and RCP 8.5 for the period 2041-2070. These are also the RCM-GCM combination and time periods used to assess the effects of climate change on the sea state and wave characteristics.

For rainfall, we make direct use of the climate change factors reported in the context of SWICCA program (Service for Water Indicators in Climate Change Adaption, 2015 - 2018), which was financed by the European Centre for Medium-Range Weather Forecasts (ECMWF) on behalf of the European Copernicus Agency within the framework of the Copernicus climate change service (C3S). Over the island of Crete, the corresponding factors are available for 9 GCM - RCM combinations (i.e. 5 for the RCP 4.5 scenario and 4 for the RCP 8.5 scenario).

We find that the increase of the mean sea level, as well as the increase in the frequency of intense storms significantly affect the frequency of port operation disruptions, particularly due to breakwater overtopping, storm induced flooding, as well sediment deposition in the harbor basin.

Acknowledgements

The presented work has been conducted under the project Climate Risk and Vulnerability Assessment (CRVA) for the Heraklion Port Authority" (project code: AA 011391-002/CC15302), which has been financed by the EIB under the InvestEU Advisory Hub.