U.S. cars and trucks, the source of 5 percent of world carbon emissions, have accounted for a whopping 20 percent of this year’s global dip in carbon pollution, according to comprehensive emissions data compiled by Carbon Monitor and recalculated by me for the Carbon Tax Center.
During the first three quarters of 2020, a period that roughly coincides with lockdowns and other restrictions from the COVID-19 pandemic, the world’s emissions of carbon dioxide from burning fossil fuels fell by more than 1.6 billion metric tons from the same period in 2019, a decline of 6.3 percent. Fully one-fifth of the decline, 320 million tons, was due to the nearly 25 percent drop in U.S. ground transport emissions. (A metric ton, roughly 1.1 short tons, is the standard metric for carbon emissions.)
Nearly half of the global CO2 decline — 787 million tons out of the overall 1,621-million-ton drop — was accounted for by reduced ground transport emissions, even though, pre-pandemic, car and truck traffic accounted for just 19 percent of total CO2. (Carbon Monitor’s other emission categories are power generation, industry, residential and aviation.)
With truck use probably little affected by the pandemic, as indicated by the mere 3 percent drop in world carbon emissions from industry (8 percent in the U.S.), the decline in ground transport emissions presumably is attributable to decreased use of passenger vehicles. The sheer size of the U.S. emissions drop, 24.5 percent, suggests that not just work commuting but the much larger discretionary or recreational driving sector — day-tripping, shopping, vacations, social and sports events, etc. — has taken huge hits.
Europe, denoted here as EU-27 & UK, presents an interesting comparison with the United States. Ground transport emissions fell less sharply in Europe than in the U.S., yet other emitting sectors contracted more in Europe than here. This too points to ample “slack” in U.S. auto use that could be reduced through policies aimed at cutting car-dependence.
In both absolute and percentage terms, the total U.S. year-on-year January-September decline — 514 million metric tons and 13.1 percent — outpaced the world’s other major emitting nations and regions. Close behind the United States in percentage terms of decline were Brazil, with a 12.9-percent drop from 2019 to 2020, and India with 11.7 percent. But because U.S. emissions are so large in absolute terms, the tonnage drop here dwarfed that of India (225 million tons) and Brazil (44 million tons).