Major breakthrough in detecting changes in carbon emissions

Scientists at the University of East Anglia (UEA) have discovered a groundbreaking new method to separate CO2 signals from plants and fossil fuels in the atmosphere.

Prior to this it was not possible to accurately detect changes in regional-scale fossil fuel emissions, forcing scientists to rely on indirect data sources which could take months or years to collect. 

Using atmospheric measurements of CO2 and oxygen from Norfolk’s Weybourne Atmospheric Observatory, researchers can now detect changes with higher frequency, such as daily estimates. 

Putting the method into practice, two periods of carbon emission reductions were discovered and were associated with UK lockdown periods in 2020-2021. 

The results correlate with three lower frequency UK emissions estimates produced during the pandemic by the Department for Business, Energy and Industrial Strategy, the Global Carbon Budget and Carbon Monitor. 

The study’s lead author, Dr Penelope Pickers, of UEA’s Centre for Ocean and Atmospheric Sciences, said: ‘If humans are to reduce our CO2 emissions from fossil fuels and our impact on the climate, we first need to know how much emissions are changing.

‘Our study is a major achievement in atmospheric science. Several others, based solely on CO2 data, have been unsuccessful, owing to large emissions from land plants, which obscure fossil fuel CO2 signals in the atmosphere.

‘Using atmospheric O2 combined with CO2 to isolate fossil fuel CO2 in the atmosphere has enabled us to detect and quantify these important signals using a ‘top-down’ approach for the first time. Our findings indicate that a network of continuous measurement sites has strong potential for providing this evaluation of fossil fuel CO2 at regional levels.’

Traditionally, CO2 emissions have been reported with a ‘bottom-up’ approach, calculated through emission factors and energy statistics.

But this can be inaccurate, particularly in developed countries, making climate targets difficult to achieve. 

Dr Pickers said: ‘The time taken for inventories to be completed makes it hard to characterise changes in emissions that happen suddenly, such as the reductions associated with the Covid pandemic lockdowns.

‘We need reliable fossil fuel CO2 emissions estimates quickly and at finer scales, so that we can monitor and inform climate change policies to prevent reaching 2°C of global warming.’ 

Photo by Marcin Jozwiak