Parked British Airways Airplanes at Gatwick Airport due to COVID19

By Lena Wege and Michael Palocz-Andresen

The COVID-19 pandemic has had a significant impact on the air traffic industry, including travel and tourism-related issues. As of 11 March 2020, since the World Health Organisation declared the COVID-19 virus to be a pandemic, commercial flights have dropped from an average of over one hundred thousand daily to less than fifty thousand1. Throughout 2020, they remained below average. As of November 2021, daily flight numbers had reached almost the same level as in November 20192. Concerning the reduction of the environmental impact of the flight industry, technological innovations play an important role, as do government-funded projects and private actors.

Introduction

This article discusses the impact of the COVID-19 pandemic on the aviation industry, with a special focus on environmental factors and flight behaviour. In order to analyse the change in the aviation industry, we need to take into account the situation before the COVID-19 pandemic. We consider the growth of the aviation sector, as well as environmental factors such as noise exposure and emissions, which have both increased significantly over the last 20 years. Apart from this, we examine the impact on the aviation industry. Environmental factors such as air pollution and noise exposure have benefited, partly due to the decline in commercial flights. Flight behaviour is an interesting factor to consider, as well, since there have been several restrictions in Europe to help contain the spread of the COVID-19 pandemic. The International Air Transport Association (IATA) travel pass has been introduced in order simplify air travel during the COVID-19 pandemic and in the future.

Technological innovations play an important role in the reduction of the environmental impacts of the flight industry, as do government-funded projects. Social norms and businesses can have an impact as well.

This paper focuses on the impacts of the COVID-19 pandemic on the aviation industry, with special emphasis on the environment and flight behaviour.

Figure 1 shows the structure of this report.

The Aviation Industry before COVID-19

We start by overviewing the aviation industry before the COVID-19 pandemic. The growth of the aviation industry in Europe has urged economic growth and investment in technological novelties and secured an easy passageway from one place to another within Europe3. In the 12 years between 2005 and 2017, air traffic in Europe greatly increased. Passengers on commercial flights increased by 50 per cent from 2005 to 2017, and this expansion can be accounted for in the overall increase in average flight distance and the introduction of smaller seats in aircraft. This means that more seats can be occupied, resulting in less fuel burn per passenger.

Within the last 15 years, there has been an overall decrease in traditional scheduled flights and an evident increase in low-cost flights. The percentage of low-cost flights more than doubled between 2005 and 2017. In 2017, they had a share of 31.7 per cent of all flights in Europe. The low-cost airlines made air travel more accessible and, at the same time, promoted economic growth and substantial growth in the aviation sector itself 3,4.

Apart from this, the aviation industry is highly likely to grow even further. In 2040, the total number of flights in Europe is expected to rise by 42 per cent to a total number of 13.6 million3. Through the modernisation of fleets and technological exposure, the efficiency of aircraft will improve in terms of fuel burn and noise.

Figure 2 shows a forecast of passenger numbers, GDP, and the jobs saved by the international aviation industry.

Environmental Impacts: Noise Exposure

Aircraft operations are a discomforting origin of noise in our environment. People living close to airports are especially affected5. Moreover, scientists have concerns regarding the health effects of the noise produced by aircraft, since some studies indicate that noise exposure is linked to an increased level of stress.

Noise exposure from aircraft is determined by decibel thresholds. The European Union Environmental Noise directive determined an indicator that averages 55 dB during the day and at night3. A noise contour depicts the areas near the airport that exceed the indicator and represents it visually. People living in the marked areas have to deal with noise disturbances, as shown in figure 3.

In Europe, the aviation industry is responsible for 3.6 per cent of greenhouse gas emissions, and this is expected to grow further. Furthermore, air pollutants such as nitrogen oxides have to be considered, which have significantly increased since 1990.
In 2017, 2.58 million people were exposed to noise disturbance3. However, the WHO recommends that decibel thresholds should be lowered to an average of 45 dB over the year during the day and at night. It is indicated that the number of people who are affected by noise disturbance is much higher. Still, noise disturbance is expected either to stabilise or decrease by 2030, depending on traffic intensity. New technologies and innovations might compensate for the increase in aircraft size.

Environmental Impacts: Emissions

Another significant environmental factor to consider is emissions. The main pollutants are carbon dioxides, nitrogen oxides, sulphur dioxide, hydrocarbons, and carbon monoxide. From 1990 to 2016, CO2 emitted by departing aircraft in Europe increased from 88 to 171 million tonnes. Even though fuel burn per kilometre per passenger has decreased immensely, it cannot compensate for the expansion of the aviation industry.

In Europe, the aviation industry is responsible for 3.6 per cent of greenhouse gas emissions, and this is expected to grow further. Furthermore, air pollutants such as nitrogen oxides have to be considered, which have significantly increased since 1990. Nitrogen oxides form acid rain in the atmosphere and cause smog. With advanced technology, fuel consumption and emissions could be reduced. However, in the aviation sector, reductions are challenging to achieve.

Situation during COVID-19: Lockdowns

Tendencies in the global CO2 emissions

Globally, since March 2020, the COVID-19 pandemic has had an great impact on human activities, such as road and air mobility. A reduction in energy and the use of fuel for vehicles and, hence, lower CO2 emissions, are to be expected as a result of the significant drop in overall individual traffic.

The Global Carbon Project (GCP)6 projects that fossil emissions in 2021 will reach 36.4 billion tons of CO2 (Gt CO2), only 0.8 per cent below their pre-pandemic high of 36.7 Gt CO2 in 2019 (see figure 4).

A recent study relied on near-real-time data to monitor global CO2 emissions8. The aim of the authors’ research was to quantify the effect of the COVID-19 pandemic on global CO2 emissions. A main result of the investigations was that global CO2 emissions decreased abruptly by 8.8 per cent (−1,551 Mt CO2) in the first half of 2020, compared to the same period in 2019. The graphs below illustrate daily and annual global CO2 emissions from recent years, with a scaling up of the daily emissions in 2019 to 2020 (see figure 4).

The GCP study revealed the sixteenth annual “global carbon budget”. The budget also showed that in 2021, both China and India exceeded their 2019 emission peaks. Emissions from China increased by 5.5 per cent between 2019 and 2021, whereas emissions from India increased by 4.4 per cent. It was also shown that Chinese coal use was a main driver of the global rebound in emissions, mainly contributed to by that country’s power and industry sectors. The use of coal, oil, and gas all decreased during the pandemic; however, both goal and gas emissions have already exceeded their pre-pandemic levels. There is a 2 per cent increase in gas emissions and a 1 per cent increase in coal emissions between the years 2019 and 2021. However, oil emissions remain around 6 per cent below 2019 levels. This persistent reduction is a main reason for why 2021 emissions have not yet surpassed the highest annual emission levels6.

Furthermore, COVID 19 caused the largest annual decrease of CO2 emissions since 1900. In the year 2020, 1.6 gigatons less CO2 per year was emitted, which is double the drop in emissions that was recorded during the Second World War. This makes the magnitude of the decrease in 2020 larger than during previous economic downturns or the Second World War. The graph on the right illustrates this finding, showing that the COVID-19 pandemic resulted in the largest decrease in CO2 emissions ever recorded (see figure 5).

Moreover, the same study collected data on the change in CO2 emissions from domestic and international aviation, comparing the years 2019 and 2020. Compared to 2019, CO2 emissions from domestic aviation dropped by a total of 35.8 per cent in 2020. This effect was even more pronounced in the area of international aviation. Here, compared to the previous year, CO2 emissions from international aviation dropped by a total of 52.4 per cent in 2020. In other words, less than half the amount of 2019 CO2 emissions occurred in the first year of the pandemic, 2020.

Improvement of Air Quality during Lockdowns

As soon as lockdowns entered into force nationwide and almost globally, numerous larger cities and metropolises started to report visibly cleaner air and greater ranges of visibility. The cause of this is, first and foremost, the decrease in aviation and road traffic, leading to less aerosol and particulate matter in the atmosphere. One of the particles that pollutes the air most is nitrogen dioxide. In the pictures below, a comparison can be seen between pre-lockdown states of 2019 and the during-lockdown situation in spring 2020, both in Milan, Italy (see figure 6).

In non-pandemic times, Milan is usually a highly polluted urban area that suffers from bad air quality and lack of visibility in the city area. The inhabitants and residents are exposed to high levels of air pollution. During the first complete lockdown in Milan, however, a drastic reduction in nitrogen dioxide pollution could be observed, which means a reduction from 15 moles x 10-5 per square metre in the worst periods of air pollution, down to roughly 10 moles x 10-5 per square metre.

According to the WHO, there are six major air pollutants: particle pollution, ground-level ozone, carbon monoxide, sulphur oxides, nitrogen oxides, and lead6. Their recent study has shown that a reduction in air pollution leads to considerable health benefits for humans. Air pollution has been shown to cause adverse health effects, such as respiratory diseases and an affection of the immune system as long-term chronic effects of exposure to polluted air. People who suffer from diseases such as asthma, pneumonia, diabetes, and respiratory and cardiovascular diseases are especially vulnerable to the effects of particulate matter inhaled through breathing the air.

Therefore, with reduced air pollution through the reduction of particulate matter and the number of particles in the air, and lower levels of all kinds of air pollutants, exposure to these health risks could be reduced.

This shows that the overall, global reduction of air pollution, especially in cities and metropolises where a huge number of people live, should be of high priority in environmental governance and policy interventions that are concerned with human health and the environment. According to UN estimates, the number of people living in cities will increase further in the near future12. In 2018, 55 per cent of the global population already lived in cities. In 2030, this percentage is expected to rise to 60 per cent13. Furthermore, the total of 33 so-called ‘mega cities’ that currently exist is expected to rise to 43 by 2030. Thus, it can be concluded that it is absolutely crucial to pay attention and make efforts to prevent air pollution that is hazardous to human health, both in international policy and in city and health governance.

Reduction of Noise Exposure during the Pandemic

The COVID-19 pandemic forced lockdowns across nations and continents. People have had to stay at home more frequently and for longer than before the pandemic, as work had to be relocated to the homes of those employees and workers for whom working at home was possible. Fewer people were commuting and travelling to workplaces that were outside their apartments and homes. The consequence was a considerable decrease in road and air traffic. This development causes a reduction in noise pollution, an effect that is most pronounced and salient in cities and metropolises that were crowded, busy and loud before the pandemic.

Researchers from New York University measured the sound profiles of a typical day in New York City at the beginning of March 2020 and compared them to the sound levels of a typical day at the beginning of May 202014. The findings, measured in decibels, are illustrated in the graph below (see figure 7).

The graph shows that the sound profiles of days during the lockdown resembled more the sound profiles of nights before the pandemic. This means that days during the pandemic were quieter even than nights before the pandemic. Moreover, the typical rhythm of the week before the pandemic, in which Mondays were louder than Sundays, disappeared.

Since the pandemic affected more or less all urban regions and cities across the globe similarly in terms of the severity of lockdown measures, it can be expected that, if the measurements had been replicated there in the exact same manner, similar findings to those from New York would have been observed in other cities from other parts of the world.

In order for the health dangers of noise pollution to stay low in the long-term perspective, road traffic needs to be reduced as much as possible. Only then can the health concerns due to noise pollution be eliminated, or at least kept to a minimum level.

The European Environment Agency (EEA) (2021) estimates that long-term exposure to environmental noise causes 12,000 premature deaths and contributes to 48,000 new cases of heart disease every year in Europe3. It is also estimated that 22 million people suffer from chronic high annoyance and 6.5 million people suffer from chronic high sleep disturbance. Therefore, a reduction in chronic noise exposure has numerous health benefits for humans, contributing to better health, sleep, and education, and the cognitive development of children.

These health effects appear when the noise exposure is long-term. Since the reductions in noise levels have been reversed again after each lockdown state due to increasing road traffic, which is the most important source of environmental noise in Europe, the dangers to human health due to noise exposure have increased again after each lockdown. According to the European Environment Agency (2021), 20 per cent of the European population live in areas where noise levels are considered harmful to health. Thus, in order for the health dangers of noise pollution to stay low in the long-term perspective, road traffic needs to be reduced as much as possible. Only then can the health concerns due to noise pollution be eliminated, or at least kept to a minimum level.

Figure 8 shows a prediction of the development of noise emission at Frankfurt Airport.

Aircraft Restrictions and Easing of Policies in the EU

Since the start of the pandemic, the health and well-being of all European citizens has been the priority of all European countries. The EU Commission’s goal is to facilitate meeting friends and family, commuting and holiday travel, but also the transport of goods, while observing and maintaining health and safety measures16. In January 2021, EU leaders discussed restricting non-essential trips across EU internal borders to contain the spread of the coronavirus, after mutant strains emerged from the UK, South Africa, and Brazil. Starting from 24 January 2021, any traveller arriving from outside the EU – possible only for those with essential reasons – had to have a test for COVID-19 before departure. To combat the virulent UK strain, the EU blocked all but freight shipments or travellers on essential trips from entering the EU from the UK 18.

The exchange of data between the EU national authorities responsible for identifying contact individuals was particularly important when travellers crossed borders in close proximity to one another, for example in planes or trains.

On 3 May 2021, against a background of ongoing vaccination campaigns and combatting the global infection rate, the Commission proposed a relaxation of the restrictions on unnecessary travel to the EU2. The Commission’s proposal intended, among other things, to enable people from countries with good epidemiological situations to enter the country. People who had received an EU-approved dose of a COVID-19 vaccine were permitted to enter. The Commission also proposed to increase the limit value for COVID-19 cases applicable to the compilation of the entry country list.

Beginning in August 2021, each EU country maintained its own standards for deciding whether and how citizens of third countries could enter if they were already in an EU or Schengen country. Each EU member state also decided and implemented its own further measures to curb the spread of the pandemic, such as quarantines upon entry from another region or country. Local regulations also differed widely on various social distancing measures, curfews and mask-wearing requirements 16.

Since it has been stated by the European Commission that vaccinations provide the best protection against COVID-19 infection and represent the most effective countermeasure to end the pandemic, people are strongly encouraged to get vaccinated, if possible. In the EU, 76.3 per cent of the adult population has already been fully vaccinated. Further vaccinations are strongly encouraged17. However, beginning in November 2021, the number of infections is steadily and rapidly increasing. Further measures beyond vaccinations to counteract rising infection numbers are currently being debated and passed.

Outlook

As mentioned before, the most likely scenario is an expected expansion of the aviation sector until 20403. In the future, with enough time for innovation, aircraft will be designed to be more resource-saving and climate-friendly. The following abstracts will consider possible future scenarios concerning the aviation industry.

IATA Travel Pass

Starting in August 2021, the International Air Transport Association planned to introduce an app in Europe and in the US for safe flight regulations. It was planned to be called the IATA Travel Pass and was designed to inform users about vaccination requirements and, at the same time, store verified COVID-19 vaccinations and testing. Although not mandatory, it was designed as a tool to simplify travel during the COVID pandemic21. So an online travel pass is a likely scenario for the future, but how can emissions be kept low and possibly change flight behaviour, even after the COVID-19 pandemic? Which innovations or political or societal engagement could make a difference?

Governments

In 2016, numerous EU member states signed a declaration to support and implement the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA). The implementation of this scheme aims to reduce CO2 emissions by offsets such as investments in wind energy or methane capture22. However, it does not intend to reduce efforts to lower carbon emissions through technology and innovation. Through carbon offsetting, the ecological footprint of the aviation industry is reduced. Basically, the participating states are required to monitor and report their fuel use, and the required offsetting schemes are calculated. The aviation industry is estimated to stabilise CO2 emissions at 600 million tons globally, instead of growing to 900 million tons by 2035. Currently, participation is voluntary, but in 2027 it will be mandatory for all states that contribute more than 0.5 per cent to global air traffic.

Furthermore, governments could provide monetary, normative, and ideological incentives for going on holiday closer to home, using psychology-based approaches like Boosts and Nudges 23. This would possibly incentivise individuals to seek out locations for going on vacation that are closer to their original homes, so fewer people overall would resort to flying to remote locations. Travelling to holiday locations nearby is a chance to drastically reduce carbon dioxide emissions.

Businesses

During the pandemic, working from home offices as experienced by many, has proven to be quite a successful and effective way to work in many cases 24. Of course, social exchange in face-to-face conversations cannot be replaced virtually but, nevertheless, trust can be fostered in online co-worker relationships and make the virtual work highly promising in terms of workplace efficiency and performance 25.

Following experiences and research findings, businesses will benefit greatly from the continued organisation of virtual conferences and virtual work via online platforms and video-based communication software, such as Zoom, Skype, Google Meets, Microsoft Teams, etc. By keeping people in virtual work from home offices in this way, emissions from commuting by cars and plane could be reduced further, and CO2 emissions be kept relatively close to pandemic-level emissions, benefiting the environment and climate system.

Aircraft Engineering and Science

The possibilities of innovation in aviation-related science are nearly limitless. Innovation in aviation technology and engineering has much potential that is yet to be harnessed, and it surely will be if funding and time are sufficient.

However, it is not only technical and economical innovation that plays a decisive role in future aviation. Hygienic aspects for avoiding future pandemics have gained a leading role in planning. Passengers give a high priority to a safe and healthy environment both at airports and in aircraft.

Figure 9 gives an overview of the most important hygienic innovations.

Conclusion

The pandemic and the extensive national lockdowns it necessitated has had an undisputable impact on environmental as well as air traffic-related issues. In comparison to pre-pandemic times, parameters such as noise and air pollution, and concentrations of various pollutants in the environment have decreased during pandemic times. Flight traffic has been enormously affected by the pandemic since global restrictions have been introduced and eased, varying depending on the country and its status quo of infection cases among the public. A desirable future scenario for the aviation industry envisions a lot of innovation to come, developing more environmental- and climate-friendly aircraft technologies that safe resources, contribute to human health and are accessible to all nations and people alike.

Acknowledgement

The authors would like to thank Prof. Dr. Thomas Schomerus, Professor for Public Law, especially Energy and Environmental Law, Associate in the Leuphana Law School, for the support of the above seminar series for many years.

This article was originally published in The European Financial Review 02 July 2022. It can be accessed here: https://www.europeanfinancialreview.com/the-aviation-industry-after-the-pandemic/

About the Authors

Lena Wege started her bachelor studies in Global Environmental and Sustainability Studies as a major, and Psychology and Society as a minor at Leuphana University Lüneburg in 2019. In her studies, she focuses on the improvement of climate change communication to the general public and post-pandemic improvements of climate-related societal issues.

Michael Palocz-Andresen has been working as a guest professor for Sustainable Mobility since 2018, supported by the Herder Program of the DAAD at the TEC Instituto Tecnológico y de Estudios Superiores in Mexico. He was a full professor at the University West Hungary until 2017. Currently, he is a guest professor at the TU Budapest, the Leuphana University Lüneburg, and at the Shanghai Jiao Tong University. He is a Humboldt scientist and instructor of the SAE International in the USA.

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