Emissions from Kiwi households have swelled by almost 12 per cent over a decade – partly because of road trips around the country - and now nearly match those of our manufacturing industries.
The latest Stats NZ figures showed that, between 2007 and 2018, direct greenhouse gas emissions from households grew by 11.8 per cent – or the equivalent of more than a megatonne of CO2 equivalent.
"As a result, New Zealand households contributed 12 per cent of New Zealand's total emissions in 2018," Stats NZ's environmental-economic accounts manager Stephen Oakley said.
By contrast, manufacturing industries contributed around 13.2 per cent to emissions.
"Household emissions grew slightly faster than the increase in the number of households, which was up 11 per cent over the same period, suggesting that since 2007 households have become slightly less efficient at managing their emissions."
In New Zealand, the three main drivers of emissions for the average household are food, housing utilities and transport.
The biggest factor in the rise was the use of vehicles, particularly when travelling around the country, which made up nearly a third of the increase.
Over the 10-year period, industries and households emitted 81 megatonnes of CO2 equivalent in 2018 – the combined total marking a small drop of 1.1 per cent since 2007.
Gains that came from decreases around electricity, gas, water, waste services and mining were largely offset by increases from households, agriculture, forestry, fishing, construction and manufacturing.
Emissions from agriculture increased by 1 per cent – or 394 kilotonnes - from 2007, but saw a significant shift in contributing industries as production shifted from sheep to dairy cattle.
Emissions from tourism meanwhile rose 16.3 per cent, and industries related to the sector accounted for 7.4 per cent of emissions in 2018.
Total industry emissions intensity – or emissions measured in relation to GDP – fell slightly by 0.2 per cent each year of the period, while GDP increased by 2.2 per cent a year.
"Despite this decrease in emissions intensity, there has been significant variation in whether and how industries are changing their emissions profile, although no industries have showed decreasing levels of economic activity along with increasing emissions," Oakley said.
Agriculture, which contributed 49 per cent of emissions in 2018, showed growth in emissions of 0.1 per cent a year while its economic activity grew 1.4 per cent a year.
Emissions from mining declined 2.6 per cent a year - more than its rate of economic activity - which declined 1.2 per cent a year.
Manufacturing and construction emissions increased 0.4 per cent a year and 5.5 per cent a year respectively, exceeding their rates of economic activity.
These industries contributed 13.2 and 1.5 per cent of emissions in 2018 respectively.
Growth in renewable energy during the period contributed to the electricity, gas, water, and waste services industry increasing its economic activity while reducing emissions.
Other industries including retail trade, finance, telecommunications and health care showed increased levels of economic activity while emissions decreased.
Victoria University climate scientist Professor Dave Frame said it was "impossible" to know how much the agriculture sector was adding to warming, given CO2 and methane were put together and reported in CO2 equivalent.
"Reporting separately by gas, or using an equivalence measure that captures contributions to warming would help New Zealanders understand how the different sectors are contributing to warming, something that isn't possible on the basis of the stats released today."
Frame also noted that transmission and tourism figured prominently in terms of emissions growth, and turning this around was vital to achieving New Zealand's 2050 goal of net zero carbon emissions.
"Other developed countries have wrestled with far higher fossil shares in electricity generation and in the manufacturing sectors," he said.
"We will have to step up in innovative ways if we are to make progress towards net zero while maintaining important sources of revenue for the country."
Generally, he pointed out New Zealand had experienced rapid population growth since 1990, which continued to drive up emissions.
"Migration and climate policy need to be joined at the hip, so that we anticipate, plan for and resource appropriate low-carbon infrastructure as we grow demographically," he said.
"Urban sprawl is the enemy of climate policy, but it has formed the default approach in New Zealand, where infrastructure has lagged seriously behind population growth."
Kiwis can slash their household emissions using this tool.
Are NZ women greener travellers?
Meanwhile, a new study has suggested Kiwi women use more diverse modes of travel and generate lower greenhouse gas emissions than men - despite men being more than twice as likely to travel by bike.
Otago University researchers studied the transport patterns of almost 50,000 Kiwis between 2002 and 2014 based on data from the New Zealand Household Travel Survey.
Lead researcher Dr Caroline Shaw from the University of Otago, Wellington said that while both men and women mostly travelled by car, there were distinct patterns of travel linked to gender.
Fewer women regularly cycled (2 per cent) compared to men (5 per cent) but women travelled shorter distances.
"Women took more trips, but travelled between 12 and 17 per cent fewer kilometres per day and were more likely to walk and use public transport than men," she said.
"Thus, women overall had a more diverse and lower greenhouse gas emission travel profile than men."
Women also took more car trips of less than 5km each day than men, journeys that could potentially be made by bike.
The research focused on Kiwis who cycled for utility or transport reasons.
The most common reasons for travel were to accompany others, go shopping or make social visits.
In general, men took fewer trips for the purpose of accompanying others and made fewer shopping trips.
"We found differences in mode for trips for the same purpose by gender. For example, shopping trips undertaken by men in New Zealand are much more likely to be done using a car than those by women."
Shaw said there was much significant potential to support increased cycling among women in New Zealand.
"Women are already more flexible and lower carbon travellers than men. We need to provide them with better opportunities and support to do more of this type of travel."