Warmer water at the seaside might sound nice for your holiday dip, but recent ocean heat in the Mediterranean Sea has been so intense that scientists fear potentially devastating consequences for marine life.

The temperature of the sea surface regularly passed 30C off the coast of Majorca and elsewhere in late June and early July, in places six or seven degrees above usual.

That's probably warmer than your local leisure centre swimming pool.

It has been the western Med's most extreme marine heatwave ever recorded for the time of year, affecting large areas of the sea for weeks on end.

The heat appears to be cooling off, but some species simply struggle to cope with such prolonged and intense warmth, with potential knock-on effects for fish stocks.

To give you some idea of these temperatures, most leisure centre swimming pools are heated to roughly 28C. Competitive swimming pools are slightly cooler at 25-28C, World Aquatics says.

Children's pools are a bit warmer, recommended at 29-31C or 30-32C for babies, according to the Swimming Teachers' Association.

Such balmy temperatures might sound attractive, but they can pose hidden threats. Harmful bacteria and algae can often spread more easily in warmer seawater, which isn't treated with cleaning chemicals like your local pool.