The United Nations' World Meteorological Organisation (WMO) has this week released the WMO Greenhouse Gas Bulletin, a report, which shows that levels of carbon dioxide and other greenhouse gases in our atmosphere have continued to increase, despite the shutdown of travel and industry in many parts of the world as a result of Covid-19 lockdowns.
Emissions arising from transport and other activities are thought to have been reduced by up to 7.5% as a result of lockdowns, but the WMO described this as a 'tiny blip' in the buildup of greenhouse gases caused by humans. The average monthly amount of carbon dioxide (CO2) in the atmosphere, as recorded at the Mauna Loa weather station in Hawaii in September 2020 was 411.29 parts per million (ppm), an increase of 2.75ppm on the 2019 level. Meanwhile, an increase of 2.22ppm of CO2 was observed at Cape Grim in Tasmania, Australia, with CO2 reaching an average of 410.8ppm in September 2020.
Meteorologists expect CO2 levels to vary by up to 1ppm from year to year as a result of natural fluctuations in climate, but these readings are considerably above that level. If we want to limit global temperature increases to 1.5C above per-Industrial levels, climate scientists have calculated that we need to cut greenhouse gas emissions in half by 2030.
The atmospheric concentration of CO2 is now double what it was in 1750. Meanwhile, the atmospheric concentration of methane gas, which is responsible for around 17% of global heating is now 2.5 times what it was in 1750. Methane gas is emitted by cattle, rice paddies and as a by-product of fossil fuel extraction. Increasingly, methane is being emitted from the arctic tundra as the permafrost thaws and bubbles of the gas that have been frozen in the ice for thousands of years are freed and bubble to the surface.
The Secretary General of the WMO, Petteri Talaas said, "CO2 remains in the atmosphere for centuries. The last time the Earth experienced a comparable concentration was 3 million-5 million years ago, when the temperature was 2-3C warmer and sea level was 10-20 metres higher than now. But there weren’t 7.7 billion [human] inhabitants."
He continued with this message of hope, "The changes are economically affordable and technically possible and would affect our everyday life only marginally,”......"It is welcome that a growing number of countries and companies have committed themselves to carbon neutrality. There is no time to lose.”