More greenhouse gases were produced in 2018 than any previous year, despite more than 20 countries reducing their carbon emissions since 2000.

New international research suggests that while the COVID-19 pandemic may have brought about a temporary reprieve in carbon emission, a return to the previous upward trajectory of greenhouse gas production is likely as economic growth moves back to previous levels.

The study was completed by a team of 29 researchers from six continents that examined the latest, globally available emissions data for the decade leading up to 2018.

The study divided sectors into the five major groups of energy, industry, buildings, transport, and land use. 

Lead author of the study, researcher Dr William Lamb from Berlin’s Mercator Research Institute on Global Commons and Climate Change, says global greenhouse gas emissions increased by 11 per cent from 2010 to 2018.

“Only a few sectors saw a significant downward trend, such as the energy sector in Europe,” Dr Lamb says.

“By contrast, climate-damaging coal power generation increased in Asia. And emissions in the transport and building sectors rose in almost all regions of the world – this was in part because people in rich countries are travelling more and more and taking up more and more living space.”

The study also found that global freight travel activity grew by 68 per cent in the last two decades, while the largest emitter overall was the industrial sector, adding the equivalent of 20.1 gigatonnes of CO2 worldwide in 2018, which was 35 per cent of total emissions and 14 per cent more than in 2010.

The trend towards greater floor space area in new buildings was also highlighted as a driver of emissions. 

With 55 square metres per person in floor space, Australia belongs to the top three countries driving this trend, local researchers note.

“Looking at the trend towards larger houses in Australia, we’re seeing people spend more of their time indoors and that that drives up energy demand because a larger house needs more cooling or heating,” says Professor Tommy Wiedmann from UNSW’s School of Civil and Environmental Engineering.

“You need to fill that house with furniture, with furnishings, with appliances, and so the general level of material consumption is also driving up and it goes hand in hand with greater emissions.

“Of the five sectors that we looked at, buildings was the smallest one with 6 per cent globally of total emissions. But if you count the electricity used in buildings for heating, cooling, lighting, and allocate this to buildings, then the share goes up to 17 per cent.”

Prof Wiedmann says an often-overlooked sector responsible for emissions was the land sector, which may be responsible for up to a quarter of climate pollution.

“From 1990 to 2018, humans have shrunk primary forest areas by more than 7 million square kilometres, almost as much as the size of Australia,” he says.

“This is often for pasture and cropland in Latin America, Africa and South-East Asia that now produces food for Europe, North America or China.

“Land use emissions are also driven by a ‘westernisation’ of diets, with meat and internationally sourced refined products replacing traditional and seasonal produce.”

The full study is accessible here.