Thursday 9 May 2024

Global temperature heat streak continues with April officially the hottest on record.

Extract from ABC News 

ABC News Homepage


Australia may have shivered through its coldest April since 2015, but the rest of the world continued to break heat records for the 11th month in a row.

The global average temperature for the last 12 months — May 2023 to April 2024 — has once again reached a new record, at 1.61 degrees Celsius above the 1850-1900 pre-industrial average, according to data released by the European Union's Copernicus Climate Change Service.

Despite some parts of the world, including Australia, bringing the average down, it was the hottest April on record, 1.58C above pre-industrial levels.

Hot spells in Europe, North America, the Middle East, eastern Asia, parts of South America and most of Africa contributed to the high global average.

Andrew King, a meteorologist at the University of Melbourne, said the latest records weren't surprising.

"It shows how the world is warming and we know that's due to our greenhouse gas emissions," he said.

"We've got other factors in place, as well as, of course, the gradual, creeping rise of concentrations of CO2 in the atmosphere.

"It is a clear indication of the damage that humans are doing to the planet."

What about El Niño?

Global sea surface temperatures also continued to break records, with April the 13th month in a row to be the warmest on record.

While the record run of high temperatures has largely been caused by rising greenhouse gas emissions, especially the burning of fossil fuels, it has been boosted by El Niño.

"Even in a fairly normal year these days, because of the warming of the planet, we usually still see months that are maybe third or fourth warmest on record," Dr King said.

"It doesn't require too much more heat to get it to record levels and that's kind of what the El Nino really provides."

But climate scientists say there is a margin to the extreme heat the world has experienced over the past year that can't be explained by global warming or known climate drivers.

The wild temperatures are expected to moderate somewhat as El Niño weakens, but Carlo Buontempo, director of the Copernicus Climate Change Service, said the warm oceans will continue to have an impact on temperatures.

"El Niño peaked at the beginning of the year and the sea surface temperatures in the eastern tropical pacific are now going back towards neutral conditions.

"However, whilst temperature variations associated with natural cycles like El Niño come and go, the extra energy trapped in the ocean and the atmosphere by increasing concentrations of greenhouse gases will keep pushing the global temperature towards new records."

Dr King said that's because oceans react more slowly than land.

"The ocean acts fairly slowly, it's much slower to take up heat and move around heat than the atmosphere is," he said.

"There's kind of some delayed effects in the ocean, which basically mean you can still see quite high temperatures continuing beyond an El Nino event."

A cold and dry central Australia

The Bureau of Meteorology's (BOM) data for April showed the national mean temperature was 0.51C below the 1961–1990 average, the lowest since 2015.

"No one experiences the global average temperature," Dr King said.

"It's not too surprising that Australia hasn't been super hot at the same time as the global temperatures have been unusually hot.

"But the global average temperature is a good indicator of how the climate is changing because it smooths out a lot of that weather and climate variability we see around the planet."

Frost and cool air rises on cold morning in paddock at Jimboomba, south of Brisbane.
Australia recorded the coldest April in almost 10 years.(Supplied: Jennifer Forrest)

It was also dry across much of the country, with rainfall 26 per cent below the 1961–1990 average.

The temperature averages were brought down by the extremely cold lows in parts of South Australia and the Northern Territory, with the mean minimum temperatures the 10th lowest since 1910.

And in some places the lowest minimum temperature on record.

Despite a slightly cooler April, the BOM's winter outlook is for above-average temperatures.

No comments:

Post a Comment