Emissions After Lockdown


Unlocking the potential of green initiatives is the key to achieving the dramatic reduction in CO2 emissions we saw during lockdown.

Lockdown measures in response to the COVID-19 crisis led to a temporary 17% drop in global carbon emissions. The extent to which world leaders consider climate change when planning their economic response post COVID-19 is the key to reducing global carbon dioxide (CO2) emissions for decades to come.


Humankind needs to dramatically reduce global carbon emissions to limit climate change in line with the objectives of the UN Paris Agreement. 


Prof. Corinne Le Quéré led the analysis of an international study that showed the global lockdown decreased daily CO2 emissions by 17% (17 million tonnes of CO2) globally during the peak of confinement in early April compared to an average day in 2019 - a drop equal to levels last seen in 2006.

  • Surface transport emissions - (mainly car journeys) accounted for almost half (43%) of the decrease in global emissions during peak confinement on April 7. 
  • Industry and power emissions - accounted for a further 43% of the decrease in daily global emissions. 
  • Aviation emissions – accounted for a 10% decrease in emissions during the pandemic (this economic sector was most impacted by the lockdown but only accounts for 3% of global emissions).
  • Residential building emissions – a small increase in emissions caused by people working at home only marginally offset the reduction in emissions from other sectors.
  • Individual country emissions - decreased by 26% on average at the peak of their confinement.

The estimated total change in emissions from the pandemic amounts to 1048 million tonnes of CO2 (MtCO2) until the end of April. Of this, the changes are largest in China where the confinement started, with a decrease of 242 MtCO2. Then it’s the US (207 MtCO2), Europe (123 MtCO2) and India (98 MtCO2). The total change in the UK for January-April 2020 is an estimated 18 MtCO2.

The impact of confinement on 2020 annual emissions is projected to be around 4% to 7% compared to 2019, depending on the duration of the lockdown and the extent of the recovery. If pre-pandemic conditions of mobility and economic activity return by mid-June, the decline would be around 4%. If some restrictions remain worldwide until the end of the year, it would be around 7%.


This ‘extreme’ decrease in daily carbon emissions will not last. 

The analysis showed that social responses alone, without increases in wellbeing and/or supporting infrastructure, will not drive the deep and sustained reductions needed to reach net zero emissions.

This annual drop is comparable to the amount of annual emission reductions needed year-on-year across decades to achieve the climate objectives of the UN Paris Agreement.However, opportunities do exist to make real, durable, systemic changes and be more resilient to future crises. These include implementing economic stimulus packages that also help to meet climate targets, especially for mobility, which accounts for nearly half the decrease in emissions during confinement. For example, instead of building roads, cities and suburbs can support walking, cycling and the uptake of electric bikes. This approach is far cheaper, preserves social distancing and improves air quality, as well as health and wellbeing. 


This study brought together a team of scientists from around the world. Together they analysed government policies on confinement for 69 countries responsible for 97% of global CO2 emissions. 

At the peak of the confinement, regions responsible for 89% of global CO2 emissions were under some level of restriction. Data on activities indicative of how much each economic sector was affected by the pandemic was then used to estimate the change in fossil CO2 emissions for each day and country from January to April 2020.

Professor Corinne Le Quéré

Corinne is a Royal Society Research Professor of Climate Change Science at the School of Environmental Sciences here at UEA. 

Corinne led the study, which helped to highlight that while global carbon emissions have temporarily reduced during lockdown, the real changes will come from the alignment of actions post-COVID that both help to reduce global carbon emissions and rebuild economies.

The study authors also warned that the rush for economic stimulus packages must not make future emissions higher by delaying New Green Deals or weakening emissions standards.

“Population confinement has led to drastic changes in energy use and CO2 emissions. These extreme decreases are likely to be temporary though, as they do not reflect structural changes in the economic, transport, or energy systems.”

Corinne Le Quéré



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