Summer is extending in Spain, but not evenly into the seasons on either side. According to an analysis of 44 weather stations covering 1971 to 2018, the season began an average of 6.76 days earlier per decade, while its end moved back by 2.74 days per decade. Aemet has also reported that summer in Spain has grown by around 10 days per decade since the 1980s.
The figures suggest the shift is taking a greater share from spring than from autumn. The term “primaverano” has been used to describe summer-like conditions arriving in spring, while “veroño” refers to warm autumn days. AEMET reports that the spring encroachment has exceeded 30 days in some areas of central and northern Spain.
Autumn’s changes are more limited and vary by region. The analysis found a statistically clear extension of summer into autumn mainly along the Cantabrian and Mediterranean coasts, where the season has gained roughly two to three weeks over recent decades. In western Spain, the extension rarely exceeds a week.
The effects also differ across the country. The Pyrenees and the northeast are among the areas most affected, while the south, much of the Cantabrian coast and Galicia show more stable summer durations. At the La Molina observatory, the number of days with distinctly summer-like heat rose from 49 between 1979 and 2000 to 69 in the most recent quarter-century.
The article attributes the accelerated lengthening to the pace of global warming since 1979. It also cites a study published in Geophysical Research Letters, which warned that, without steep cuts to emissions in the Northern Hemisphere, summers lasting almost six months could become normal by 2100.
Sources: Xataka.