Explained: UK and France prepare for another heat wave as western Europe sets new temperature record

The UK and France are bracing for their fifth heat wave of the season

El Nino

A periodic warming of parts of the Pacific Ocean that leads to temperature variations around the globe

Amber heat health alert

A UK warning level indicating significant impacts on health services, including a rise in deaths among older and vulnerable people, are likely

Extrapolar oceans

Oceans free of seasonal sea ice, as distinguished by the European climate agency Copernicus

Copernicus

The European climate agency that tracks and reports global temperature and climate data