Transportation Sector Emissions and Climate Change

Transportation is a massive and growing problem contributing to the climate crisis. As a large and increasing source of greenhouse gases (GHGs) we will need to see significant changes if we are to keep emissions from pushing us past the internationally agreed upon upper temperature limits (1.5-2C above preindustrial norms).  Emissions from the transportation sector account for between a quarter and a third of global greenhouse gas emissions.

According to the UN Food and Agricultural Organization a sector by sector comparison of GHG emissions indicates that transport accounts for more than 20 percent of atmospheric CO2.

As reported by Vox the US transportation has recently surpassed energy as the largest source of domestic emissions. As reported by a more recent article in  Popular Mechanics,
the transportation sector accounts for around 23 percent of the world’s
carbon dioxide emissions stem from transportation.  In the U.S. that
number is even higher at 29 percent.

A new study indicates that maritime shipping is also a problem.
The research was conducted by scientists at the International Institute
of Applied Systems Analysis (IIASA), Laxenburg, Austria and published in
the Energy Conversion and Management.  “The maritime
shipping sector is a major contributor to CO2 emissions and this figure
is expected to rise in coming decades,” reads the paper’s abstract.
Shipping represent around 3 percent of transportation emissions.

The most carbon intensive form of transportation comes from aircraft.  Aircraft account for 12 percent of transportation emissions and in 2018 when air travel reached record highs. At the current rate emissions from air travel will increase seven-fold globally by 2050.  This is not sustainable and we will need to find solutions if we are to keep emissions from pushing temperatures beyond critical thresholds.