Overview

• Met Office data show sea surface temperatures running 1.5°C–3°C above 1982–2012 averages, with readings up to 20°C in the English Channel.
• Since early July, North Wales beaches from Rhos-on-Sea to Colwyn Bay have seen unprecedented numbers of giant barrel jellyfish wash up.
• Portuguese man-o’ war are appearing weeks earlier than usual, pushed ashore by warmer Atlantic currents.
• The Marine Biological Association and CEFAS warn that elevated temperatures could trigger harmful algal blooms and stress shellfish species.
• Beachgoers are urged to wear protective footwear and keep vinegar sachets on hand for sting treatment instead of using urine.