Global Warming

Global Warming: Air traffic poised to become a Key Factor

It’s not just road transport that is having a significant effect on global warming – air traffic is also seen as a major contributor. One round trip from NY to LA or Trans Atlantic round trip is equal to 2,000 pounds of CO2; in a year air travel releases 600 million tons of carbon dioxide [...]

It’s not just road transport that is having a significant effect on global warming – air traffic is also seen as a major contributor. One round trip from NY to LA or Trans Atlantic round trip is equal to 2,000 pounds of CO2; in a year air travel releases 600 million tons of carbon dioxide into the atmosphere. By the year 2050, increased flights by jet airplanes will impact global climate through the greater number of contrails they will produce, according to a study.

The ghostly white trails following airplanes and rockets through the sky, called contrails, are probably adding to global warming. The contrails often turn into cirrus clouds, a thin, wispy type of cloud made of ice crystals. Persistent contrails can exist long after the airplane that made them has left the area. They can last for a few minutes or longer than a day. However, because they form at high altitudes where the winds are usually very strong, they will move away from the area where they were born. Persistent contrails are those most likely to affect climate.

The first new projections of future aircraft emissions in 10 years predicts that carbon dioxide and other gases from air traffic will become a significant source of global warming as they double or triple by 2050. The study is in ACS’ Environmental Science & Technology, a semi-monthly journal.

The study, published in the ACS Journal Environmental Science & Technology, outlines that aviation is not currently one of the main drivers of global warming – it currently contributes between two and three per cent of carbon dioxide emissions.

However, it is predicted that by 2100 carbon dioxide emissions from aviation could reach seven times their existing levels. To reach this conclusion they used a global model of aircraft movements and emissions to calculate fuel use and emissions to 2050 and beyond. The scenarios saw the authors examine technology trends in detail and develop plausible projections for fuel efficiency and emissions for each scenario.

Bethan Owen and colleagues note that aviation is not now one of the main drivers of global warming, with international aviation (source of 60 percent of carbon dioxide emissions from aircraft) not even included in the Kyoto Protocol. Global air traffic currently contributes to between 2 and 3 percent of carbon dioxide emissions — the main “greenhouse” gas linked to global warming.

The scientists’ computer model forecast that emissions of carbon dioxide will likely double or triple within the next 50 years. By 2100, carbon dioxide emissions could increase by up to seven times the current levels, they say. “Even though there have been significant improvements in fuel efficiency through aircraft technology and operational management, this has been outweighed by the increase in air traffic,” the study states.