North America endured hottest June on record

Satellite data shows temperature peaks are lasting longer and rising higher

North America endured the hottest June on record last month, according to satellite data that shows temperature peaks lasting longer as well as rising higher.

The heat dome above western Canada and the north-west United States generated headlines around the world as daily temperature records were shattered across British Columbia, Washington and Portland.

The new data reveals this was part of a broader trend that built up over several weeks and a far wider area, which is underpinned by human-driven climate disruption.

The European Union’s Copernicus Climate Change Service also revealed that June temperatures in North America were 1.2C higher than the average from 1991 to 2020, which is more than 2C above pre-industrial levels.

This is the 12th consecutive year of above-average June temperatures in the region, and the greatest increase recorded until now.

At the start of the month, the record-breaking heatwave conditions were centred over the south-west of the US. They then moved over the north-west of the US and south-west Canada, causing more than 500 heat-related deaths and creating tinder for wildfires. The town of Lytton in British Columbia broke Canada’s heat record three days in a row. The latest hydrological bulletin shows many of the affected regions had unusually dry soil.

Northern Europe and Siberia also experienced an unusually hot June. Temperature records were broken in Moscow and Helsinki. The world as a whole was also warmer than average for this time of year. This would not normally be expected in the same year as a La Niña phenomenon, which is generally associated with a cooling effect.

Meteorologists said these anomalies were made more possible by the broader pattern of warming, which was caused by human emissions.

“Natural variability and a warming trend make a freakish event even more freakish,” said Carlo Buontempo, the director of the Copernicus Climate Change Service. “Because the climate is generally warming and so even in Niña year we see very high temperatures.”

7 July 2021

The Guardian