Lockdowns did not halt increase in greenhouse gases

happened despite the 5.6 per cent drop in fossil fuel CO2 emissions caused by the pandemic restrictions.

British Prime Minister Boris Johnson said yesterday that it was ‘‘touch and go’’ whether the Cop26 climate change conference, which starts in Glasgow on Sunday, would succeed in convincing all countries to adopt targets to reach net-zero emissions by 2050. The government admitted in a report that rich nations had fallen short of fulfilling a promise to provide poor nations with US$100 billion (NZ$140 billion) a year to combat climate change.

The last time the Earth had similar concentrations of CO2 in the atmosphere was three to five million years ago, when the temperature was 2C to 3C higher than it is now and sea levels were 10m to 20m higher. CO2 concentration is now at 149 per cent of the preindustrial level, methane at 262 per cent and nitrous oxide at 123 per cent.

In July the CO2 concentration at Mauna Loa observatory in Hawaii, where levels have been monitored since 1958, reached 416.96ppm, compared with 414.62ppm a year earlier.

About half the CO2 emitted by human activities stays in the atmosphere and the remainder goes into oceans and land. The WMO warned that the ability of oceans and land to act as ‘‘carbon sinks’’ may decrease in future, reducing their ability to act as a buffer against more rapid temperature increases.

In July scientists said that the Amazon rainforest, previously a major carbon sink, was emitting more CO2 that it was able to absorb. – The Times