Carbon Emissions and Turbulence

As global carbon emissions continue to surge from burning fossil fuels, research suggests that pumping out more carbon dioxide into the atmosphere will significantly increase instances of severe airline turbulence. In 2019, the world’s carbon pollution from fossil fuels reached a record high, which is the third year in a row where emissions have surpassed a new record (Meyer, 2019). Research conducted as part of the Global Carbon Project published 2019 global carbon emissions data in the scientific research journals of Environmental Research Letters, Nature Climate Change, and Earth System Science Data. The results published in these journals show that even as the decline of the coal industry in North America and Europe has started to accelerate, the expansion of coal-fired power plants in the developing countries of Bangladesh, China, and India continues to contribute to a notable rise in global greenhouse gas emissions. In addition to increasing global sea level rise and other impacts from climate change, higher levels of carbon dioxide in the atmosphere could alter jet streams and increase airline turbulence.

Research conducted by University of Reading atmospheric scientists suggests that global warming could make flying even more stressful than it is today, by contributing to bumpier airplane rides. For nervous fliers, the data released as part of this study is harrowing to say the least. As a result of increased carbon dioxide in the atmosphere, the research suggests that severe instances of turbulence at a common airline cruising altitude of 39,000 feet is expected to rise by over 181 percent over the North Atlantic, 161 percent in the skies above Europe, 113 percent above North America, 92 percent above the North Pacific, and 64 percent above Asia (Frangoul, 2017).

According to chief researcher and atmospheric scientist Paul Williams, the increasing levels of carbon dioxide in the atmosphere will have an impact on the narrow, high-altitude channels of fast-moving air known as jet streams, which will make severe turbulence more than twice as likely to occur by the middle of this century (Josephs, 2017). Australia’s Civil Aviation Safety Authority (CASA) characterizes severe turbulence as large and abrupt changes in attitude (relating to an aircraft’s orientation) or altitude, as well as significant variations in electronic airspeed indicators, which may temporarily make an aircraft uncontrollable by on-board pilots (Frangoul, 2017). The resulting increase in pockets of violently rough pockets of air can make even the most experienced flyers feel weary about their next flight.

Increasing Emissions from Coal

Continued investments in fossil fuels used in electricity production, transportation systems, and manufacturing industries is set to continue to increase carbon dioxide in the atmosphere. While carbon-intensive forms of fossil fuels like coal have struggled in recent years throughout the world’s developed countries as a result of the changing economics of the energy industry, coal continues to thrive in the developing world. In the U.S., the coal industry is struggling. In 2019, Murray Energy, America’s largest private coal company, announced that it would be filing for bankruptcy. Moreover, the Navajo Generating Station, which was one of America’s largest coal-fired power plants, shut down its power generation operations for good at the end of 2019. The shift to cheaper and cleaner sources of power like natural gas and renewable energy has started to make coal obsolete in North America and Europe. Since 2010 alone, more than 540 coal-fired plants have closed in the U.S. (Stevens, 2019). However, coal still remains prominent in the developing world.

In the coming decades, Southeast Asian countries are expected to massively increase investment in coal-fired power generation. In order to effectively address the region’s rapidly growing economies and the increasing demand for more electricity, the governments of Bangladesh, China, and India have been working on plans to increase access to affordable and reliable electricity to raise the standard of living for residents that have long been without access to energy. To achieve these energy and affordability goals, the region is turning to coal. In Bangladesh alone, a proposal to increase power capacity from coal by 63 times over the present day will add 115 million tons of new carbon dioxide to the atmosphere by 2031 (TIB, 2019). All this new carbon will continue to contribute to rougher flights in the future.

The Dangers of Clear-Air Turbulence

A study from the scientific journal, Advances in Atmospheric Sciences, says that by the time carbon dioxide levels in the atmosphere have doubled from what they were before the Industrial Revolution, severe turbulence will be 149 percent worse compared to where it was in the 1850s (Fekri, 2017). Anthropogenic (originating from human activity) climate change is expected to strengthen vertical wind shears within the jet stream at cruising altitudes. Alterations in the atmospheric jet stream may increase the prevalence of jet stream instabilities that generate a phenomenon known as clear-air turbulence, which has become one of the most prevalent causes of weather-related aviation incidents. Through a series of climate modelling studies, scientists have found that the amount of moderate to severe clear-air turbulence on transatlantic flight routes will increase significantly in future (particularly in the winter months) as the climate changes (Williams, 2017).

The increasing prevalence of clear-air turbulence has many aviation experts concerned because of its potential to cause hospitalizing in-flight bumpiness for unsuspecting aircraft. Often invisible to the naked eye and undetectable by onboard sensors, clear-air turbulence can be defined as high-altitude aircraft bumpiness in regions without the presence of clouds or thunderstorm activity (Chambers, 1955). Without any warning, planes can be violently thrown around by this phenomenon. Any objects that are unsecured, as well as unbuckled passengers and members of the flight crew can be tossed around the cabin, resulting in serious injuries and even fatalities (Storer et al, 2017). The cruising phase of a flight above 10,000 feet in altitude is the most prone to instances of violent clear-air turbulence because passengers and crew are often free to roam about the cabin. Despite recent advances in aircraft technology, clear-air turbulence accounts for 24 percent of weather-related aircraft accidents (Storer et al, 2017).

Failed Climate Initiatives

Under the Paris Climate Accord, 200 countries agreed on a legally binding plan to cut greenhouse gas emissions and keep increases in the global temperature to below 2 degrees Celsius (Karim, 2019). As global leaders were meeting to set a goal of limiting global warming, carbon emissions started to stabilize. For nearly three years, from 2014 to 2016, global carbon emissions from burning fossil fuels did not increase at a statistically significant level (Meyer, 2019). However, since then, the world’s carbon emissions have started to surge again. The brief hope that the 180-year acceleration in carbon pollution was coming to an end has now vanished. China has cut its subsidies for solar and wind power, while greenhouse gas emissions in the U.S. have been skyrocketing under the lenient environmental policies of the Trump administration, which amounts to disconcerting news for frequent flyers hoping for incident-free flights.

Increasing Injuries

As incidents related to in-flight injuries continue to make media headlines, turbulence of all severities is expected to increase according to advanced model simulations of a warming climate (Miller, 2017). However, given that the largest increase in turbulence is expected to be in the form of severe turbulence, many more cases of serious injuries are expected to occur on future flights. The science behind the link between climate change and airline turbulence is a relatively straightforward concept. As human-produced emissions continue to influence the intensity and position of jet streams, the turbulence from jet streams would also be expected to become increasingly unpredictable. While the greatest potential for severe turbulence is expected in the future as carbon emissions continue to climb, evidence shows that turbulence-related injuries have risen substantially since the 1980s, even after modifying the data to make up for the annual growth of the aviation industry (Miller, 2017).

According to an assistant professor of meteorology at the University of Oklahoma, Dr. Jason Furtado, “The consensus of the climate models is that global climate change will cause the [average] position of the jet stream to shift closer to the poles in both hemispheres” (Miller, 2017). In addition to the increasing strength of the jet stream, the shift in jet stream positioning is expected to cause significant disruption for the aviation industry. Researchers have extensively studied this phenomenon by using advanced supercomputers to specifically evaluate turbulence over the Atlantic Ocean, which is the busiest oceanic corridor for air traffic. As carbon dioxide levels were increased significantly in the computer models, the impact on the jet stream became easily apparent. As the carbon emissions increased, atmospheric temperatures changed all the way up to 40,000 feet in a manner that is not uniform, creating pockets of unstable air that are invisible to unsuspecting aircraft.

Troubling Research Results

In the U.S. alone on an annual basis, there are roughly 60,000 planes that encounter moderate turbulence and 5,000 that encounter severe turbulence (Fekri, 2017). As a result of this turbulence, hundreds of flight attendants and passengers are injured each year. Since the risk of turbulence is expected to double or triple in the coming decades, there will also be a risk of seeing double or triple the amount of turbulence-related injuries. This risk is particularly worse for smaller aircraft, which are more easily thrown around by severe pockets of rough air. Moreover, since increasing the amount of fossil fuel emissions will also cause the jet stream to move closer to the poles in both hemispheres, this would put the jet stream directly in the path of the most traveled section of the sky between Europe and North America. Because many airlines will attempt to avoid the path of severe jet streams conditions, trips from Europe to North America are expected to take longer and cost more, as more fuel will be needed to cut through the strengthening headwinds. Conversely, flights to Europe from North America may be shorted, due to the increasing speed of jet stream tailwinds.

Technology Changes

While the results of atmospheric studies related to the impact that fossil fuel consumption will have on incidents of turbulence may be troubling, aviation experts highlight that more research is needed to determine how increasing carbon emissions will impact the jet stream during each season of the year. According to the International Air Transport Association, air turbulence is already the top cause of injuries in non-fatal airplane accidents (Josephs, 2017). In anticipation of a future characterized by more incidents of severe turbulence, researchers say that more advanced systems of sensors are needed to alert pilots about oncoming turbulence. American Airlines and Alaska Airlines have already been investing in new technology to make real-time turbulence predictions more accurate for pilots. As many new aircraft that will be released in the coming decades are already in the design phase, it is imperative that more research is conducted to better inform airline manufacturers how to prepare for a more turbulent atmosphere. Since emissions from fossil fuels are expected to increase in the coming decades, aeronautical advances that include remote sensing for clear-air turbulence could prevent a countless number of injuries in the future.

Sources

Chambers, E. (1955). “Clear air turbulence and civil jet operations.” The Aeronautical Journal, 59(537), 613–628

Fekri, F. (2017). “Climate Change Will Make Airplane Turbulence Much Worse.” VICE.

Frangoul, A. (2017). “Climate change will increase the risk of severe turbulence on planes, research says.” CNBC.

Karim, N. (2019). “Bangladesh seen as climate threat by boosting coal reliance.” Reuters.

Josephs, L. (2017). “Global warming could make flying even more awful than it is today.” Quartz.

Meyer, R. (2019). “5 Big Trends That Increased Earth’s Carbon Pollution.” The Atlantic.

Miller, B. (2017). “Climate change expected to make turbulence stronger and more frequent.” CNN.

Stevens, P. (2019). “One of the largest coal-fired power plants in the Western US has just closed for good.” CNBC.

Storer, L., et al. (2017). “Global Response of Clear-Air Turbulence to Climate Change.” Geophysical Research Letters. 44, 9976–9984.

TIB. (2019). “Choked by Coal: The Carbon Catastrophe in Bangladesh.” Transparency International Bangladesh.

Williams, P. (2017). “Increased Light, Moderate, and Severe Clear-Air Turbulence in Response to Climate Change.” Department of Meteorology, University of Reading: Advances in Atmospheric Sciences: Vol. 34, 576–586.