Socioeconomic inequalities in greenhouse gas emissions from household travel in Aotearoa/New Zealand

Background: A just transition to a decarbonised transport system requires understanding current inequity in transport-related greenhouse gas emissions (GHGe). Methods: We used the population-based nationally representative New Zealand Household Travel Survey (2015-2018 data) to examine inequalities in GHGe from household travel by NZDep (an area measure of socioeconomic position [SEP]). Results: There was a broadly linear association between SEP and GHGe from household travel. People resident in the least deprived areas emitted around 79 % more GHGe per week from household travel than those in the most [mean 63.6 CO2eq (95 %CI 58.5-68.6) compared to 35.6 kg CO2eq (95 %CI (32.6-38.6)]. Most of the difference was due to the additional 97 km per week travelled by car by people resident in the least deprived areas. Residents in the least deprived areas travelled further and more frequently for paid and unpaid work and leisure purposes than those in the most. Air travel also showed significant inequities with 2.4 % of residents in the least deprived areas reporting air travel in the last week compared to 0.1 % in the most deprived. Air travel was the second largest source of mean weekly transport emissions in residents living in the least deprived areas. Conclusion: There are large inequities by area deprivation in GHGe from household travel in Aotearoa/New Zealand. Transport policy needs to focus on measures to reduce emissions that are effective and reduce inequities. Significant work on policy processes, design and evaluation need to occur to facilitate this dual transformation.