Emissions, heat reach record levels
Greenhouse gas concentrations, sea levels, ocean heat and ocean acidification all hit new records last year, in what the United Nations says was a ‘‘litany of humanity’s failure to tackle climate disruption’’.
The past seven years have been the warmest ever, according to the World Meteorological Organisation’s (WMO) annual State of the Climate report.
It warns that climate change is compounding with the impacts of war and the Covid-19 pandemic to ‘‘undermine decades of progress towards improving food security globally’’, with a growing number of countries at risk of famine.
Extreme weather events were causing hundreds of billions of pounds of economic damage, the WMO report said, pointing to drought in the Horn of Africa, deadly flooding in South Africa, and extreme heat in India and Pakistan.
The concentration of carbon dioxide reached 413.2 parts per million (ppm) globally, or 149% of the pre-industrial level. The level continued to rise this year, reaching 420.23 ppm last month.
Average sea levels reached a new record in 2021 after increasing at an average 4.5mm a year over the period from 2013 to 2021 – more than double the rate between 1993 and 2002. The acceleration is mainly due to the faster loss of ice from polar ice sheets.
The upper 2000m of the global ocean continued to warm last year, and the report said heat was ‘‘penetrating to ever deeper levels’’. Much of the ocean experienced at least one ‘‘strong’’ marine heatwave.
The temporary cooling effect of the natural La Nina weather phenomenon meant that last year was only the fifth-warmest year on record globally. However, Britain’s Met Office, which contributed to the report, said it was ‘‘almost inevitable’’ that one of the next five years would break the record for the warmest year ever, set in 2016.
Exceptional heatwaves broke records across North America and the Mediterranean last year. Drought affected many parts of the world, including the Horn of Africa, Canada, the western United States, Iran, Afghanistan, Pakistan and Turkey.
UN Secretary-General Antonio Guterres said the report showed the urgent need to transform energy systems away from the ‘‘dead end’’ of fossil fuels.
Guterres called for a tripling of private and public investments in renewables and an end to subsidies on fossil fuels, which amount to roughly US$11 million (NZ$17.4m) a minute.
The punishing heat that has scorched northwest India and Pakistan for weeks was probably made 100 times more likely due to human-caused climate change, a new analysis by the Met Office suggests.
The heat, which began in March, has altered the way of life for millions of people in the region and cut crop yields.
The analysis used the recordsetting heatwave in April and May 2010 – which this year is set to surpass – as a benchmark. In the absence of climate change, an event like the 2010 heatwave would only be anticipated every 300 years, the analysis found.
India endured its highest March temperatures in 122 years of records. It was then the hottest April on record in Pakistan and northwest and central India.
Temperatures are running well above average in May as well, at between 42C and 50C.
Vimal Mishra, a climate scientist at the Indian Institute of Technology, said the heatwaves were unprecedented in the past 100 or more years for their early onset, persistence and widereaching impacts.
– The Times, Washington Post