United states — Since the 1970s, the volume of passenger travel by vehicles and airplanes has experienced significant growth in industrialized countries. The International Energy Agency had previously projected a continuous, albeit slower, expansion in travel until 2030 and beyond. However, a recent study conducted across eight industrialized nations reveals that passenger travel likely reached its zenith in the early 2000s, just before the notable surge in fuel prices. This development suggests a potential saturation point in the demand for travel, challenging previous expectations of escalating carbon dioxide emissions and fuel consumption.
The research, led by Lee Schipper from the University of California, Berkeley, and Adam Millard-Ball, a doctoral candidate at Stanford University, scrutinized travel patterns in the United States, the United Kingdom, Canada, Sweden, France, Germany, Japan, and Australia from 1970 to 2008. Their analysis encompassed various modes of transportation, including cars, pickup trucks, buses, planes, trains, light rail, streetcars, and subways, comparing the distance traveled per capita per year with each country’s gross domestic product per capita.
The study identified a correlation between rising prosperity and passenger travel from 1970 to 2003. After this period, passenger travel ceased its growth trajectory, even as GDP per capita continued to rise. At the peak of travel in the early 2000s, the GDP per capita was $37,000 in the US and ranged between $25,000 and $30,000 in the other seven countries. Subsequently, motorized travel in the US plateaued at around 26,000 km/year per person, 10,000 km/year per person in Japan, and between 13,000 and 17,000 km/year per person in the remaining six countries.
In recent years, the study noted a leveling off or decline in motorized travel demand in most of the countries analyzed, with a decrease in travel via private vehicles. Despite an increase in car ownership, these vehicles are being driven less frequently. The researchers attributed this travel plateau to various factors, including saturation in vehicle ownership, time constraints, high gas prices, and an aging population less inclined to commute.
A significant factor contributing to the observed travel plateau, according to the researchers, is traffic congestion. Lee Schipper emphasized that the limited road space in densely populated cities worldwide impedes further growth in car usage. While acknowledging the importance of fuel efficiency and hybrid vehicles in addressing emissions, Schipper highlighted that even zero-emission cars contribute to traffic problems.
One potential advantage of the apparent peak in travel is that if passenger travel remains stable while vehicles become more fuel-efficient, the challenge of reducing transportation emissions may be less daunting than previously anticipated. Presently, the average American car consumes one-third less fuel per mile than in 1973, despite consumer preferences for larger vehicles.
Despite the study’s findings not being conclusive, the researchers urge caution in assuming that travel demand will inevitably continue to rise. They recommend further research to refine our understanding of these trends and their implications.