Posted on August 7, 2024
With $67bn in world trade at risk annually from climate damage to commercial ports, the sector needs to bolster resilience.
As extreme weather events spike globally, commercial ports – critical hubs that connect 80% of world trade volume – are reckoning with the rapidly materialising climate crisis threats of rising sea levels, storm impacts and drought.
In a blow to global trade, 2023 saw the Panama Canal hit with the worst drought in 73 years, slashing the vital route’s daily capacity from 36 ships to a low of 22. The previous year, South Africa’s heaviest rains in more than 60 years halted operations at the Port of Durban, which handles 60% of the country’s shipments.
Similarly, Hurricane Harvey – the second most expensive natural disaster in US history – battered Greater Houston and Southeast Texas in 2017 with more than 9 trillion gallons of rain, disrupting the Port of Houston’s operations for around two weeks.
This is just the beginning. The impact of the climate crisis is set to intensify this century as temperatures continue to rise.
According to a 2024 study, 86% of 1,340 of the most important ports globally are exposed to more than three types of climate and geophysical hazards. Port downtime associated with these natural hazards puts trade worth $67bn at risk every year, with knock-on impacts on the global economy.
What are the main threats to commercial ports?
Climate change effects, such as coastal and inland flooding, frequent wave overtopping, low water depth, and intense precipitation, are expected to cause operational disruptions to ports globally. This could cost an estimated $7.6bn per year, mostly attributed to tropical cyclones and river flooding.
Speaking to Ship Technology, Giulia Sforzi, principal engineer at HR Wallingford, a civil engineering and environmental hydraulics research and consultancy, explains: “The most significant climate impact risk to ports is rising mean sea level. Increased frequency and intensity of storm events are also a major risk, particularly in certain regions.”
“Other climate change impacts that need to be considered for ports, particularly in certain parts of the world, are bigger storm surges [and] more precipitation, more intense precipitation at times, changes to wave conditions, and increases in the occurrence of major tropical cyclones.”
As the ocean warms at an unprecedented rate, sea level rise is also faster than expected and could exceed 1 metre by the end of the century and reach up to 5 metres by 2300. A spokesperson at Associated British Ports (ABP) also tells Ship Technology that the biggest threat to its port operations due to the climate crisis is a rising sea level.
The most significant climate impact risk to ports is rising mean sea level.
“ABP cannot move its operations away from the coast. Sea level rise will mean that ports’ risk from flooding will increase but ABP can be flood resilient,” the ABP spokesperson remarks.
“A flooded quay could prevent the offloading or loading of ships, resulting in a financial impact for the port,” adds Sforzi. “The operating of other infrastructure, such as water systems, wastewater systems, the transport network and critical infrastructure, could also be at risk.”
Storms can suddenly shift sediment, filling in a berth or channel and making it unusable.
“Climate change could also have a knock-on effect on the requirements for maintenance dredging,” Sforzi continues. “For many ports, this is a significant part of their operational planning and costs, yet dredging needs can vary greatly from year to year because of changing patterns of storminess, river discharge, and wave direction.”
On the other end of the scale, heatwaves can cause thermal expansion, mechanical malfunctions, and deform infrastructure like lock gates and lifting bridges. Rising ocean acidity due to excess carbon dioxide dissolving could increase corrosion and degradation of undersea port infrastructure – and ships.
Climate adaptation is on the rise
There are various ways that ports are adapting. Port owners are making upgrades to infrastructure such as breakwaters, floodgates, sea walls, quays, and berths that include physically raising the facilities, waterproofing valuable assets, and building flood and heat resilience.
For example, Immingham, the UK’s largest port by tonnage, has been modified to protect against storm surges. ABP, which owns and manages Immingham, says: “Physical adaptations have been made to the port, in particular, new outer lock gates have been installed, which have a higher crest height and can be held in position against a reverse head of water in the event of a repeat surge.”
Legislation or regulation can be used to direct this adaptation. The ABP says that the 2008 Climate Change Act in the UK requires port authorities to provide voluntary climate adaptation reports.
In Europe, the Climate Resilience Port Infrastructure (CLARION) project is being implemented to enhance the climate resilience and sustainability of ports across the continent. Recommended steps include extreme weather forecasting, a monitoring system for the corrosion of port infrastructure, flood-impact control, and future-proofing port infrastructure.
The project is funded by the European Union’s collaborative research programme Horizon Europe, based at TU Delft University in the Netherlands.
The Port of Antwerp-Bruges plans to manage dock water closely to improve clean water flows.
A spokesperson for the Port of Antwerp-Bruges, which is participating in the CLARION project along with the ports of Rotterdam and Hamburg, says: “Flanders is a very vulnerable region to drought. The likelihood of extreme drought and water scarcity will only increase as a result of the climate crisis.
“At the same time, we are facing rising sea levels and excessive water levels due to heavy precipitation. It is therefore in everyone’s interest that the right amount of clean water flows through the docks.”
The Port of Antwerp-Bruges plans to mitigate this risk by managing dock water levels, quality, and infrastructure by regulating the issuance of permits for dock water capture, addressing pollution, and managing sewage systems.
According to the Brussels-based World Association for Waterborne Transport Infrastructure (PIANC), physical adaptation is not always required if planning and early warning systems are up to scratch. 24-hour warnings for storms or heatwaves are reported to reduce economic losses by 30%.
The Port of Seattle implemented preventative risk assessment procedures following disruptions due to extreme rainfall and high wind speeds in 2021. “Relatively few” ports and waterways are taking the urgent action required to bolster climate resilience, according to a report by PIANC. Without climate adaptation, the number of ports at high, very high, or extremely high risk will increase significantly by 2100.
How can ports adapt best?
Although some ports in Europe and the UK are making plans for future conditions, the global port sector remains lacking in resistance planning but is uniquely exposed to future climate crisis events.
The ABP explains one reason for the slow change: “Ports are very specialised, individual pieces of infrastructure. The adaptation process will therefore need to be uniquely tailored to each individual circumstance.”
Climate risks vary geographically, and each port location has unique meteorological conditions responsible for generating waves.
“The water surfaces around the ports can change in terms of its free surface where waves can generate and then propagate. Plus, the characteristics of the seabed vary, which has an impact on the way waves propagate towards the port,” explains Sforzi
Considering that existing ports have often been developed over decades or centuries, Sforzi emphasises the importance of these ports to review design standards and performance of existing assets to ensure that they are accounting for the latest climate predictions.
It’s also important for ports to plan in advance how to rapidly replace structures and minimise downtime in the event that they are damaged or fail.
“They need to be thinking about designing assets, for instance, the quay wall and the crest of the breakwaters, so they can easily be upgraded or adapted,” adds Sforzi.
“It’s also important for ports to plan in advance how to rapidly replace structures and minimise downtime in the event that they are damaged or fail. Damaged infrastructure should be replaced with solutions that reflect long-term changes in climate, rather than like for like, as per the philosophy of the Sendai disaster recovery framework.”
While ABP, like other port owners, has been investing in building higher and more robust sea defences as a solution, it admits this may not be a long-term solution. ABP’s spokesperson says that ports need to find more “innovative ways” of adapting to allow their specific functionality to continue.
A 2020 study found that seaports are expected to grow fourfold by 2050 and global investment costs for port adaptation will be between $223bn to $768bn by then. Of this, only $13bn to $53bn relates to the adaptation of existing ports, with the remainder needed to prepare new ports for the impacts of the climate crisis in the coming century.
Whether the bill falls at the door of governments or private investors, deep pockets will be needed to keep deepwater ports open for business.
