Cruise Ship Emissions Soar as Vessel Sizes Double Since 2000

The number and size of cruise ships have skyrocketed since the early 2000s, causing a dramatic rise in carbon emissions, according to a new study by the think tank Transport & Environment (T&E).

The recently published Cruisezilla report predicts that if current trends continue, the largest cruise ships by 2050 could be nearly eight times the size of the Titanic, with a massive 345,000 gross tonnage and the capacity to carry almost 11,000 passengers.

Since 2000, cruise ships have doubled in size. The world's largest cruise ship, Royal Caribbean's Icon of the Seas, launched in January 2024, features 40 restaurants and seven swimming pools and accommodates 7,600 passengers. This colossal vessel is longer than 15 blue whales and five times the size of the Titanic.

The study notes that the number of cruise ships has surged from just 21 in 1970 to over 500 today.

T&E warns that the increase in the number and size of cruise ships has led to a nearly 20% rise in CO2 emissions from cruise ships in Europe in 2022 compared to pre-pandemic levels in 2019.

The study also highlights that this industry growth has exacerbated air pollution problems on land. For instance, Southampton, the UK's busiest cruise ship port, ranks seventh in Europe for sulfur oxide emissions from cruise ships and experiences the highest levels of nitrogen oxides and delicate particulate matter from ships in the UK.

T&E urges cruise ship operators to invest in green technologies to mitigate their environmental impact and reduce local air pollution.

"With today's cruise ships making the Titanic look like somebody's private yacht, the question is - how much bigger can these giants get?" said Jonathan Hood, UK sustainable shipping manager at T&E. "The cruise business is the fastest growing tourism sector and its emissions are spiralling out of control."

In response to criticism over their emissions, some cruise operators are transitioning to liquefied natural gas (LNG) as an alternative to traditional heavy fuel oil. T&E reports that LNG-powered ships currently represent 38 percent of global cruise ship orders.

Although LNG burns cleaner than traditional fuels, reducing pollutants and CO2 emissions, it has environmental drawbacks. LNG combustion still produces carbon emissions and can release methane, a greenhouse gas with a warming potential over 80 times greater than CO2.

"The only solution for decarbonising maritime activities that's both sustainable and scalable is zero-emission, hydrogen-based fuels," said Hood. "The UK needs to make switching away from filthy fossil fuels an absolute priority by setting binding targets for the use of clean fuels as well as for ports to support zero-emission technologies.

"That also includes shore side electricity, which allows cruise ships to plug in at berth and to switch off their polluting engines, allowing the residents of ports like Southampton to breathe easy."

The think tank also advocates for policymakers to consider a ticket tax to generate climate finance for emissions reduction initiatives. T&E argues that new levies on cruise ships are warranted, mainly because these vessels are currently exempt from fuel duties and most corporate and consumer taxes.

T&E has calculated that a £42 ticket tax—less than half the UK air passenger duty for a long-haul economy-class seat—on a typical cruise ticket priced at around £1,180 could generate £1.37 billion globally.