A record drop in carbon emissions has been estimated this year due to worldwide lockdowns – but scientists have warned this will have no impact on the overall amount of carbon dioxide in the atmosphere.
The projected decline is similar to the annual reduction needed every year between 2020 and 2030 in order to limit the increase of the global temperature.
However, the most recent data shows global carbon dioxide (CO2) concentrations – the principal factor in global warming – are at their highest level on record despite industry, transport and air travel shutting down for many months.
In May, there were 417.07 molecules of CO2 per million of dry air (ppm), the highest since measurements began in 1958, the United States National Oceanic and Atmospheric Association (NOAA) found.
CO2 concentrations are also expected to rise this year, with the latest Met Office forecast estimating an increase of 2.48ppm – 0.32ppm smaller than if there had been no lockdown, equivalent to 11% of the expected rise.
This means that although global emissions have decreased this year, they are continuing – just at a slightly slower rate.
More CO2 is still accumulating in the atmosphere and it takes decades for most of it to dissolve into the ocean, while the rest can take up to several hundreds of thousands of years to be removed through processes such as rock formation.
Atmospheric physicist Professor Piers Forster, from the University of Leeds, said the only way to fight the increase in C02 emissions is for governments to lead the way.
He told Sky News: “Countries are waking up to the issue but they also have the problem that their economies still depend on fossil fuel infrastructure to a very large extent.
“There are opportunities with the investment going into recovery.
“We argue that we can transition our industries into renewable energies and there are more exciting jobs for a more resilient community – it does require a strong leadership though.”
‘Unprecedented’ drop in carbon emissions
There is no real-time data to monitor global emissions, but several studies have estimated the extent to which the COVID-19 pandemic has contributed to the fall in emissions.
The first peer-reviewed study on the subject, by the University of East Anglia (UEA), estimated the daily fossil CO2 emissions fell by “a probably unseen before” 17% in early April compared with 2019 due to global lockdowns.
The analysis, which included countries and regions that account for 97% of global CO2 emissions, found an annual decrease of around 4.2% to 7.5%.
This is similar to the International Energy Agency (IEA) forecast of “an unprecedented” decline of 8% compared with 2019.
Of that total reduction in global emissions, surface transport (road, train and boat), power and industry accounted for 86% of it, UEA research found.
Energy demand was 3.8% lower in the first quarter of 2020 compared with the same time last year, the IEA report said, and the annual fall could be between 4% to 6% – a drop not seen in 70 years.
However, the UEA report said: “Most changes observed in 2020 are likely to be temporary as they do not reflect structural changes in the economic, transport or energy systems.
“Our study reveals how responsive the surface transportation sector’s emissions can be to policy changes and economic shifts.
“Surface transport accounts for nearly half the decrease in emissions during confinement, and active travel (walking and cycling, including e-bikes) has attributes of social distancing that are likely to be desirable for some time and could help to cut back CO2 emissions and air pollution as confinement is eased.”
Other air pollutant emissions also declined during lockdown
New research from the University of Leeds, led by Prof Forster, also found reductions in global emissions from other types of air pollutants due to global lockdowns.
Levels of global pollutants decreased in January as a result of China’s lockdown and slightly increased when China’s toughest restrictions were relaxed and before COVID-19 hit other countries.
The main drop at the end of March coincides with the introduction of strict measures in many Western countries.
CO2 and nitrogen oxides (NOx) emissions likely fell due to a decline in transport, methane is driven by the power sector and sulphur dioxide is primarily affected by industrial emissions.
Despite these decreases, researchers said: “The direct effect of the pandemic-driven response will be negligible (in global temperature rises), with a cooling of around 0.01C ± 0.005C by 2030.
“In contrast, with an economic recovery tilted towards green stimulus and reductions in fossil fuel investments, it is possible to avoid future warming of 0.3 °C by 2050.”
Dr Chris Huntingford, a climate researcher at the UK Centre for Ecology and Hydrology, said the pandemic has highlighted how some industries are “very emissions intensive” but to avoid “dangerous climate change we need to get to almost zero emissions”.
“We also need to think about who gets affected the most if we have a policy of very rapidly lowering emissions,” he said.
“There needs to be investment in technologies and grants to support industries, such as travel, to continue but with a transition to energy sources that produce less greenhouse gas emissions.”
The China case: Lowered emissions can bounce back
Analysis by the Centre for Research on Energy and Clean Air (Crear) estimated that emissions fell by 25% in China in the six weeks after lockdown but have increased since people returned to work. Emissions in May 5% higher compared with the same month last year.
CO2 emissions in China rebounded mainly due to the construction and industrial sectors, with coal power and cement production the principle driver, while oil demand has returned to the previous year’s levels.
An increase in petrol usage suggests a shift from public transport to private cars, something seen in the UK as well.
Image: Satellite images show nitrogen dioxide levels have fallen over China. Pic: NASA
During lockdown, the heavily polluted skies above China’s cities were clear but by early May air pollution was back to pre-pandemic levels, mainly because of industrial emissions.
“There are early warning signs that China’s recovery from the COVID-19 crisis is reversing air quality gains,” a report from the Centre for Research on Energy and Clean Air found.
It said the return of air pollution was obvious, but it is “not obvious whether air pollution will overshoot pre-crisis levels, especially when many economic sectors are still reeling”.
“Such an overshoot would signify a ‘dirty’ recovery in which the more highly polluting sectors are leading,” the report said.
The 1.5C target needs a consistent decline
2020 is set to be the hottest or second hottest year on record after 2016, new analysis by Carbon Brief has found.
Greenhouse emissions from human activities – mainly fossil fuels – is the main driver of global warming, with CO2 one of the most prolific emissions.
The UN Environment Programme warned in order to meet the Paris Agreement target of limiting global temperature increases to 2C, and ideally 1.5C, above pre-industrial levels by 2030, global emissions should fall by 7.6% every year between 2020 and 2030.
That would mean a sustainable decrease – similar to that seen during lockdown – for 10 years.
The Intergovernmental Panel on Climate Change (IPCC) also says the world needs to achieve net-zero emissions by 2050 to meet temperature goals.
As of June, 20 countries and some regions adopted net-zero targets, including the UK – but they only represent around 10% of global emissions.
More than 100 countries have committed to working on a reduction, but the world’s three largest polluters – the US, China and India – are not part of that group.
Source : Sky News