Greenhouse gas emissions were down 4.8 per cent for the year to December, largely due to a fall in transport emissions because of Covid-19.
Transport emissions were up 11 per cent in the three months to December compared to the September quarter but remained well down on pre-Covid levels.
For the year ended December 2019 transport emissions were 6037 kilotonnes, compared with the same period to 2020 when they were 3758 kilotonnes - a 38 per cent decline.
Total emissions quarter-on-quarter fell in December, after a strong rebound in September.
Stats NZ environmental economic accounts manager Stephen Oakley said this was consistent with the changes in economic activity.
"Emissions were down 1.7 per cent in the December 2020 quarter, compared with gross domestic product which was down 1 per cent."
"On the whole, transport, postal, and warehousing services emissions were down but domestic aviation and road transport emissions picked up slightly in the second half of the year, as national restrictions eased."
Household emissions were also down on an annual basis due to the large drop during the nationwide lockdown, but on a quarterly basis they rose 5.2 per cent compared to September.
"With international borders closed and overseas travel restricted, households' use of road transport picked up at the end of 2020, increasing their emissions."
Manufacturing emissions fell 10 per cent for the year largely due to less gas and coal consumption, however over the same period GDP for the sector only fell 3.1 per cent.
"We can see manufacturing emissions and GDP growth have been diverging slightly since 2018," Oakley said.
The figures are provisional, with official data published annually with an 18-month lag.
Due to the experimental nature of the data, revisions are expected as Stats NZ refines the methodology and gradually improves the quality of the series. Quarterly emissions estimates are based on information available at the time of compilation.