July was the hottest month globally ever recorded, a US scientific agency said Friday, in the latest data to sound the alarm about the climate crisis.

"July is typically the world's warmest month of the year, but July 2021 outdid itself as the hottest July and month ever recorded," said Rick Spinrad, administrator of the National Oceanic and Atmospheric Administration (NOAA).

"This new record adds to the disturbing and disruptive path that climate change has set for the globe," Spinrad said in a statement citing data from the National Centers for Environmental Information (NCEI).

NOAA said combined land and ocean-surface temperature was 1.67 degrees Fahrenheit (0.93 degrees Celsius) above the 20th-century average of 60.4 degrees Fahrenheit, making it the hottest July since record-keeping began 142 years ago.

Dried up Little Washoe Lake in Nevada is seen in July 2021 after prolonged drought
Dried up Little Washoe Lake in Nevada is seen in July 2021 after prolonged drought GETTY IMAGES / David Calvert

The month was 0.02 degrees Fahrenheit higher than the previous record set in July 2016, which was equaled in 2019 and 2020.

However according to data released by the European Union's Copernicus Climate Change Service, last month was the third warmest July on record globally.

Zeke Hausfather, a climate scientist at the Breakthrough Institute, said it is not unusual for agencies to have small differences in data.

"The NOAA record has more limited coverage over the Arctic than other global temperature records, which tend to show July 2021 as the second (NASA) or third (Copernicus) warmest on record," Hausfather told AFP.

"But regardless of exactly where it ends up on the leaderboards, the warmth the world is experiencing this summer is a clear impact of climate change due to human emissions of CO2 and other greenhouse gases," he said.

A selection of key points of the report from the Intergovernmental Panel on Climate Change (IPCC).
A selection of key points of the report from the Intergovernmental Panel on Climate Change (IPCC). AFP / Alain BOMMENEL

"The extreme events we are seeing worldwide -- from record-shattering heat waves to extreme rainfall to raging wildfires -- are all long-predicted and well understood impacts of a warmer world," he said.

"They will continue to get more severe until the world cuts its emissions of CO2 and other greenhouse gases down to net-zero."

Last week, a UN climate science report from the Intergovernmental Panel on Climate Change provoked shock by saying the world is on course to reach 1.5 degrees Celsius of warming around 2030.

"Scientists from across the globe delivered the most up-to-date assessment of the ways in which the climate is changing," NOAA's Spinrad said.

"It is a sobering IPCC report that finds that human influence is, unequivocally, causing climate change, and it confirms the impacts are widespread and rapidly intensifying."

With only 1.1 degrees Celsius of warming so far, an unbroken cascade of deadly weather disasters bulked up by climate change has swept the world this summer, from asphalt-melting heatwaves in Canada, to rainstorms turning city streets in China and Germany into rivers, to untamable wildfires sweeping Greece and California.

NOAA said the land-surface only temperature for the Northern Hemisphere was the highest ever recorded for July -- 2.77 degrees Fahrenheit (1.54 degrees Celsius) above average, surpassing the previous record in 2012.

Asia had its hottest July ever, surpassing 2010, it said, while Europe had its second-hottest July, trailing only 2018.