The global airline industry supports 87.7 million jobs worldwide, drives $3.5 trillion of global economic activity (direct and indirect), and accounts for ~4.1% of global GDP, which we think is the most relevant figure given the distorting effects of the COVID-19 pandemic on air travel demand. In 2019, the industry also emitted 914 million tons of carbon dioxide (CO2), which represents 2.1% of global human CO2 emissions (43.1 billion metric tons in total CO2 emissions).
Advancement in technology has helped to reduce emissions during the past few decades.
The positive ratio of GDP contribution to emissions is a function of an industry that has benefited from billions of dollars of investment in fuel-efficient aircraft and engines, the most technologically advanced flight management software, enhanced ground operations, and other efficiency measures.
The US airline industry in 2019 supported over 10 million US jobs, drove $1.6 trillion of direct and indirect economic activity, contributed ~5% of US GDP, and accounted for ~2% of CO2 emissions. In Figure 1 below, we highlight the operational efficiency of air travel since 1990: a flight a passenger takes today will produce an average 55% less CO2 than the same flight 30 years ago due to the deployment of new technology, operational efficiencies, and improved fleet utilization. See Figure 1 on next page showing CO2 per passenger/kilometre.
More information here.