By 2050, global demand for air travel will more than double, according to the International Air Transport Association (IATA). Growth will be concentrated primarily in emerging markets, such as Asia, Africa, and Latin America, while demand will rise less sharply in Europe and the Americas.

However, without a radical breakthrough in Sustainable Aviation Fuels (SAF) or hydrogen technology, pressure on the industry to tax or restrict flights will only increase.

20.8 trillion revenue passenger kilometers

In Europe and North America, the market is nearly saturated, but in regions such as China, India, Southeast Asia, and Africa, air travel will also become the norm for the growing middle class.

IATA’s positive outlook proves that there is still plenty of room for growth. In a moderate growth scenario, demand for air travel would rise to 20.8 trillion revenue passenger kilometers (RPK), up from 9 trillion in 2024.

Even in the most conservative scenario, demand would more than double, reaching 19.5 trillion revenue passenger kilometers. The scenarios consider various parameters, such as economic growth, population trends, and jet fuel prices.

With an estimated global population of 9.7 billion people in 2050, this means that, on average, every person on Earth will take a long-haul flight more than once a year. By comparison, today most of the world’s population (over 80%) has never flown or flies only rarely.

In the average scenario, demand would grow by 3.1% each year. “We expect Asia-Pacific, Africa, and the Middle East to be the main drivers of growth,” IATA states in its report.

Annual growth in Asia-Pacific would be 3.8% and in Africa 3.6%. In Europe, North America, and Latin America, annual growth is projected to range from 2.5% to 2.8%.

Stress test for the planet

“People want to travel,” says IATA CEO Willie Walsh. According to him, this is “good news for global economic and social development, because growth in the aviation industry creates opportunities worldwide, such as jobs.”

But facilitating these miles also poses a serious stress test for the planet. For instance, hundreds of new ‘mega-hubs’ will need to be built, especially in India, Southeast Asia, and Africa.

In many of these areas, building airports is faster and cheaper than constructing an extensive high-speed rail network across difficult terrain. The construction of these new airports would, however, have a local environmental impact, namely, concrete use and loss of biodiversity.

It is also estimated that 45,000 to 50,000 active commercial aircraft will be needed, compared to the current total of about 25,000. This will place enormous pressure on global supplies of critical raw materials and will have a significant ecological footprint even before the first liter of fuel is consumed.

4 to 5 gigatons of CO2

Moreover, aviation is one of the most challenging sectors to make sustainable. If demand doubles while technology lags behind, we are heading toward a massive emissions gap.

Currently, aviation accounts for approximately 2% to 3% of global CO2 emissions. If the number of passengers doubles, this share threatens to rise explosively, especially since other sectors, such as energy and road transport, are becoming greener more rapidly.

In 2024, this average was around 90-100 grams of CO2 per RPK, resulting in a total of 855 megatons of CO2. Without technological improvements, emissions would more than double by 2050 to nearly 2 gigatons of CO2 per year.

The actual climate impact is also greater than just CO2 emissions. At high altitudes, aircraft also emit nitrogen oxides (NOx) and water vapor, leading to contrails. Scientists often use a Radiative Forcing Index (RFI) of 1.9 to 3.0. This means that you must multiply the CO2 impact to understand the total warming effect.

In the 20,800 trillion RPK scenario, the total climate impact amounts to approximately 4 to 5 gigatons of CO2. This is nearly 10% to 15% of the total carbon budget remaining to humanity to stay below 1.5°C of warming.

$5 trillion in investment needed

Currently, the aviation sector is aiming for an annual efficiency improvement of approximately 1.5% to 2%. By 2050, emissions per RPK could theoretically drop to around 50-60 grams thanks to more efficient engines and lighter materials. However, to achieve ‘Net Zero’, the remaining emissions must be offset by SAFs and carbon sequestration.

Nowadays, however, SAFs account for less than 1% of total fuel consumption, and unlike Europe, which has introduced strict blending mandates (RefuelEU), the fastest-growing markets often still lack policies for SAFs.

IATA estimates that we will need approximately 500 million tons of SAF by 2050. Current projections indicate that without massive government support, we will likely remain stuck at around 400 million tons. The report thus shifts responsibility, in part, from airlines to policymakers (for subsidies) and to the energy sector (for production).

Consequently, to make the 20.8 trillion RPK scenario in 2050 climate-neutral, more will be needed than just flying a little more efficiently. The cost of this transition is also enormous.

It is estimated that some 5 trillion dollars in investments will be needed between now and 2050. This means that flying will likely become significantly more expensive in the future, which could, in turn, dampen demand.