By analysing real-time data from Carbon Monitor, the study backs the theory that due to there being less cars on the road, less energy being used by industry and less aviation and shipping emissions, CO2 levels fell to record lows. The study estimates that there were 3.9 billion people adhering to lockdown guidelines across the world, and while they helped to slow the spread of the COVID-19 virus, they also contributed to an unprecedented decline in carbon emissions. Bigger than the financial crisis of 2008, the oil crisis of 1979 and the Second World War. According to the data, there was 8.8 per cent less carbon dioxide emitted, the equivalent of 1.5 billion tonnes. “What makes our study unique is the analysis of meticulously collected near-real-time data,” said lead author Zhu Liu from the Department of Earth System Science at Tsinghua University in Beijing. “By looking at the daily figures compiled by the Carbon Monitor research initiative, we were able to get a much faster and more accurate overview, including timelines that show how emissions decreases have corresponded to lockdown measures in each country.” At the height of lockdown, the drop in emissions spiked by 16.9 per cent, a decrease which is normally only seen at major cultural festivals such as Christmas. “While the CO2 drop is unprecedented, decreases of human activities cannot be the answer,” said co-author Hans Joachim Schellnhuber, founding director of the Potsdam Institute for Climate Impact Research. “Instead we need structural and transformational changes in our energy production and consumption systems. Individual behavior is certainly important, but what we really need to focus on is reducing the carbon intensity of our global economy.”