Changes in transport behaviour during the Covid-19 crisis

For the energy sector, this trend has had huge knock-on effects for oil consumption, contributing to a 5% decrease in demand in the first quarter of 2020. With passenger transport responsible for around 40% of final oil demand and 15% of global energy-related carbon emissions, any crisis-induced changes to way we travel will have significant global implications, if changes to transport behaviours become permanent after lockdowns are lifted.

Therefore, a key question for the energy sector is whether changes to transport behaviours during the crisis may result in a permanent change in behaviour (and transport energy use) or if transport patterns will revert to ‘business as usual’ when the crisis ends. Research has shown that disruptions can be a catalyst for shifts towards more sustainable transport behaviours but avoiding a return to pre-crisis behaviours requires governments to take decisive actions.

While the current crisis is unprecedented, in terms of the scale of impacts and government responses, examining past crises can be instructive in informing policy makers how people’s behaviours can change during and immediately following a crisis, and what sort of policy options are available to government to incentivise certain behaviours and discourage others.

In recent decades, there have been a number of crises—including multiple health and terrorism-related crises—that have caused sudden changes in transport demand, as people make significant changes to transport patterns, either in response to changes necessitated by transport disruptions, or perceived risks of travelling. This is particularly true for non-essential travel and in relatively wealthy countries where people have access to remote working facilities or alternative, private forms of transport. For other people, the decision to cease commuting during a crisis may not be an option at all.

Mass transport, which brings people into close proximity with each other, is where some the most tangible behavioural changes manifest during a crisis, particularly air transport, which is generally perceived as being non-essential.

For example, the Severe Acute Respiratory Syndrome (SARS) crisis of 2003 reduced demand for passenger air transport in the affected regions by about 35% at the height of the crisis. Demand continued to be below business-as-usual levels six months after the epidemic had eased, resulting in an 8% annual decrease of revenue passenger kilometres. The SARS crisis also affected non-essential trips on public transport. In Taipei, there were half as many underground trips during the peak of the SARS epidemic and it took four months for passenger numbers to return pre-crisis levels.

Several other viruses emerged since the SARS outbreak that affected aviation demand including the Avian Flu outbreaks of 2005 and 2013 and Middle Eastern Respiratory Syndrome in 2015. In these cases, demand for air travel bounced back relatively quickly. However, it is reasonable to assume that the public’s response to Covid-19 will more closely resemble the response to SARS, as the scale of the impacts and the perceived risks of contagion are much greater compared to more recent pandemics. Already, surveys of public attitudes to risk suggest that people in most countries will take time before feeling confident enough to travel again. In another survey, two out of five passengers in major aviation markets want to wait for at least six months before travelling again.

From a behavioural perspective, the speed at which air travel demand resumes may also depend on whether responses to the virus permanently change the way we travel. For example, increased health checks may help to provide a sense of security for some passengers. Alternatively, if such procedures make flying a more complicated and time-consuming mode of transport, potential air travellers could be dissuaded from flying.

The combined impact of passengers’ perceptions of danger and inconvenience on transport demand was demonstrated in 2001, following the September 11 terrorist attacks (9/11). After 9/11 there was a large drop in demand for air transport, as business and leisure passengers reassessed both the risks and inconvenience of flying after new security precautions were introduced. Studies showed that the overall impact on air transport was long-lasting: despite bouncing back, some analysts estimate that US domestic air passenger travel was over -7% lower in the five years after the attacks than it would have been, had they not occurred.

In China, the domestic aviation market is starting to rebound as domestic travel restrictions are eased. However, the extent to which the Covid-19 crisis will affect global aviation demand in the longer term remains to be seen. Modelling by the International Civil Aviation Organisation (ICAO) suggests the short-term (within 12 months) impact will be a severe drop in passengers under most scenarios.

If and when demand for passenger air transport returns to pre-crisis levels will depend on a range of factors including perception of risk, cost, convenience, and the availability of alternative transport modes, all of which affect people’s mobility decisions. Government policies (discussed below) can influence each of these factors. Concerning business travel, Covid-19 could be different from previous crises, if companies determine that replacing business trips with videoconferencing is more feasible as technologies mature.

In addition to direct demand reductions for particular modes of transport, previous crises also show that people often adopt new transport practices during and immediately following a crisis, which can sometimes become permanent, depending on a range of factors.

A clear example of modal shifts in response to a crisis came after the London terrorist attacks in July 2005, when a series of bombs exploded in three London underground trains and one bus, killing 56 people and injuring another 700.

Although the damaged underground lines reopened within weeks, the attacks had longer lasting impacts on the city’s commuting patterns. Londoners avoided underground journeys for months and partly switched to other modes of transport such as cycling. Bike retailers in London reported that sales quadrupled in the week following the attack and bike use increased by 13% from June to July. Cycling trips remained high until the end of 2005, with a 9% annual increase in registered trips compared to the previous year, whereas car, bus and underground use decreased.

For many commuters, the bombings may have acted as a catalyst for switching to active transport modes, convinced after experiencing benefits such as cost and time savings over public transport or better health. However, other factors also contributed. For example, the introduction of the congestion charge for private vehicles entering central London had contributed to a strong increase in bike use since 2003 and more than half of the respondents in a 2004 survey mentioned the charge as a key trigger for cycling more.

The availability of infrastructure was also key to keeping attracting new cyclists in the years following the bombings. For example, a growing network of dedicated ‘quietways’ and fully-protected ‘cycle superhighways’ (since 2010) has been crucial in attracting additional first-time cyclists by providing safer conditions.

It should also be noted that despite the increase in cyclists stimulated by the crisis, the overall impact on commuting patterns was relatively insignificant in terms of long-term changes to transport energy demand: bicycles still only accounted for 2.5% of all trips in London in 2018 despite the 2.6-fold increase in bike rides since 2000.

Nonetheless, the scale of the Covid-19 crisis could stimulate even larger and longer lasting effects on mobility patterns compared with crises like the London Bombings, depending on how the public perceives risk. That is, if the perceived risk of contracting Covid-19 on mass transport modes seemingly outweighs the safety risks associated with other modes, people might choose to switch transport behaviours for a longer period, a phenomenon known as ‘dread behaviour’.

Already reports are emerging of shifts to active transport modes out of necessity, as social distancing measures reduce public transport use. Cities such as New York and Philadelphia were reporting a substantial increase in cycling (the number of cyclists more than doubling in the latter) during the beginning of the pandemic, made more attractive by unusually empty streets and better air quality. The UK’s Association of Cycle Traders reported a boom in mending as people retrieve old bicycles from their sheds, while one of the largest bike suppliers in the United States ran out of stock on some of its top selling models as sales have surged. After the lockdowns are lifted, these shifts could become more permanent if commuters' risk calculus suggests such modes pose less risk than the alternatives. In Wuhan, where the Covid-19 outbreak first emerged, since the lockdown was lifted, bike-sharing services have witnessed up to tenfold increases in ride orders compared to pre-crisis levels. 

Of course, as the perceived risks of travelling via public transport linger, people are also likely to seek out more energy intensive transport options than cycling, often for purely practical reasons. In many cities, private cars were a more dominant form of transport prior to the Covid-19 crisis and previous crises suggest car usage could spike following this crisis. For example, after 9/11, private vehicle use increased, as people sought to reduce their exposure to potential terrorist targets on mass transport. Ironically, such dread behaviour may have led to higher exposure to death by car accident.

Even in London, dread behaviour after the 2005 bombings stimulated some degree of switching from public transport to fossil-fuel powered private vehicles, in the form of motorcycles. Research suggests one of the secondary impacts of the bombings was a 7-11% increase in vehicle particulate emissions, with long-term negative impacts on Londoners’ health.

As countries begin to lift their lockdowns, it will be important to remember how people responded in previous crises and already signs are emerging that some degree of switching to more energy-intensive transport modes is likely. In one survey of consumer sentiment, 20% of people who regularly used buses, subways or trains said they no longer would, while 17% of people indicated they would use their car more due to Covid-19. Fears of Covid-19 have helped increase car sales above 2019 levels in Korea in both March and April 2020, while in Beijing, morning peak-hour traffic has recently been above normal levels as commuters opted to drive over risking public transport.

These early manifestations of dread behaviour suggest that far from ushering in the beginning of peak oil demand, behaviours in response to Covid-19 could spark a rebound in transport-related oil use when countries end their lockdowns. Governments will need to help people avoid unintended consequences that can flow from dread behaviour and more accurately assess the risks associated with their transport choices, including virus exposure, transport accidents, and the economic, environmental and health impacts of congestion.

During and immediately following the crisis, governments will understandably be concerned with issues of public health and wellbeing, including mitigating the economic impacts of the crisis. Pursuing measures to entrench sustainable transport behaviours could be one of the more effective ways to stimulate economic activity, support employment, and improve health outcomes. 

In addition to the short-term benefits that public and active transport could deliver—in terms of providing efficient mobility services after the lockdown and supporting economic growth—in the longer term, investments in public and active transport and active pay off in a number of ways. For example, the introduction of a bike sharing scheme in Washington DC has reduced traffic congestion by 4%, resulting in significant cuts in congestion-related CO2 emissions. Encouraging a shift away from car use might also reduce serious traffic-related accidents and the associated costs. In California, one silver lining of the Covid-19 lockdown has been a halving of traffic collisions and related injuries, saving the state $40 million per day.

The health benefits of promoting active transport are also potentially large, with positive impacts for public health budgets. For example, some estimates suggest that if every Londoner walked or cycled for 20 minutes a day, the UK’s public health system could save GBP 1.7 billion in treatment costs over the next 25 years. Others estimate that for each car driver switching to cycling for a daily commute of 5 km (one way), the health benefit from the physical activity is worth about EUR 1300 per year.

In large cities, higher active and public transport shares have  additional secondary health and economic benefits resulting from the associated reduction of air pollution. Such benefits are particularly relevant during the current crisis, as research on Covid-19 suggests that cities with higher levels of air pollution have been affected more adversely by the virus. Locking in more sustainable transport behaviours now might help to reduce the severity of health crises in future.

The Covid-19 crisis has changed already people’s transport behaviours in dramatic ways, with large reductions in aviation and public transport use and significant growth in cycling uptake. Evidence from previous crises shows that in the immediate aftermath of crisis events, transport behaviours will change, as people reassess the costs and benefits of different transport modes. Decision-making will be partly driven by people’s perceptions of risks, regardless of whether such perceptions are well founded or not. As lockdowns are lifted, policy will be crucial in determining whether mobility changes triggered by Covid-19 are positive or negative, in terms of their impacts energy use, safety and long-term environmental and health outcomes. Thankfully, governments designing sustainable transport policies for the post lockdown period can draw on experiences from previous crises to predict likely behaviours and design policies that are fit for purpose.