On President Joe Biden’s first day in office, he signed a letter for the United States to re-enter the Paris Climate Agreement, a coalition of nearly 200 countries working to move away from planet-warming fossil fuels like coal, oil and natural gas. The goal is to limit the global temperature increase to well below 2 degrees Celsius, and preferably to 1.5 degrees, compared to pre-industrial levels.
That’s good news for everyone who enjoys or relies upon air travel. A global temperature increase of 2 degrees Celsius would forever alter the aviation industry, concludes new research from England published in the journal Climate Risk Management.
The timing of the United States’ re-entry into the Paris Agreement is important. The 2010s were the hottest decade ever recorded on Earth, and in recent years, the Arctic Circle has been breaking temperature records.
All of this has led to rising sea levels that are impacting our coasts. According to the most recent Sea Level Rise Report Card from William & Mary’s Virginia Institute of Marine Sciences, not only are sea levels along US. coasts rising faster than before but we can expect them to rise by another half a meter by 2050. That would be a sea-level rise of more than 19 inches in less than three decades.
Professors Richard Dawson and Aaron Yesudian of Newcastle University’s School of Engineering ranked more than 14,000 airports worldwide on their risk from rising sea levels, taking into account the location of airports and their exposure to storm surges for current and future sea levels. The team also looked at the likelihood of flooding from extreme sea levels, and how the current standard of flood protection would impact flights.
The researchers found that early 270 airports around the world are currently in danger of coastal flooding due to rising sea levels. A global temperature rise of 2 degrees Celsius, which the Paris Agreement aims to prevent, would place 100 airports below sea level and 364 airports at risk of flooding. And if the Paris Agreement fails and global mean temperature increases by more than 2 degrees Celsius, as many as 572 airports will be at risk by 2100.
The Newcastle University researchers lay out the many reasons why airports are particularly vulnerable to rising sea levels. Cities are often located close to the sea, and the airports that serve those cities were often built in low-lying areas. This happened for practical reasons: it is simply easier to find suitably large areas of flat land in low-lying areas where take-off and landing trajectories minimize the risks of collision. As a result, many airports were built on reclaimed coastal wetlands, marshlands and floodplains.
Pointing to 2019 research from the Intergovernmental Panel on Climate Change that demonstrated how quickly sea levels are rising along the majority of the world’s shorelines, Dawson and Yesudian posit that the risks to low-lying airports will inevitably increase.
According to the researchers’ model, the 20 airports most at risk from climate change are all located in Southeast and East Asia, with Suvarnabhumi Airport in Bangkok (BKK) and Wenzhou Longwan Airport (WNZ) in China topping the list. Overall, China has the most airports ranked in the top 20, including Shanghai Hongqiao (SHA).
In Europe, the most vulnerable airport is Corvo Airport in the Portuguese archipelago of the Azores, followed by Bremen Airport in Germany. In the United Kingdom, London City Airport has the highest risk. If all flood protection were removed, Amsterdam Schipol (AMS) would have the highest risk, but it currently benefits from protection against the 1 in 10,000 year flood.
In the United States, Louis Armstrong International Airport in New Orleans, Nightmute Airport in Alaska, Key West International Airport in Florida, and two of the New York City area’s three major airports — La Guardia Airport and Newark Liberty International Airport — all ranked among the top 100 airports most at risk.
This is not an issue that only impacts the coasts. Rising sea levels don’t just threaten individual airports, but rather the industry as a whole. “Coastal airports are disproportionately important to the global airline network, and by 2100 between 10% and 20% of all routes will be at risk of disruption,” said Professor Dawson. “Sea level rise therefore poses a serious risk to global passenger and freight movements, with considerable cost of damage and disruption.” The team determined that up to one-fifth of air travel routes could be affected.
The researchers predict that some smaller, regional coastal airports will disappear off the map because it will not be financially viable to save them. Some regions will be disproportionately impacted because airports “provide important economic, social, and medical lifelines,” wrote the scientists.
In contrast, the major airports are typically well protected and more likely to have better access to adaptation finance. “The cost of adaptation will be modest in the context of global infrastructure expenditure,” said Professor Dawson.
The most vulnerable are the nearly 1,000 coastal airports that operate five commercial routes or fewer. “In some locations the rate of sea level rise, limited economic resources or space for alternative locations will make some airports unviable,” said Dawson.