July was the warmest month recorded in at least four decades in the Mediterranean Sea as the daily mean temperature reached an unprecedented 28.1C (82.58 F) in mid-July, according to a quarterly report by Spanish researchers.

Sea surface temperatures globally in June, July and August were 1.5C above the average from 1982 to 2023, according to scientists at CEAM, an environmental research center in Valencia, Spain. Parts of the Mediterranean were 3C above the historical average at the end of July.

A marine heat wave over the summer came as global atmospheric temperatures broke new records across the northern hemisphere. July and August were the hottest months ever recorded.

Climate change from human-made emissions of greenhouse gases has pushed up temperatures and raised the likelihood and extremity of weather events from heat waves to floods.

The Mediterranean region, which is warming 20% faster than the global average, was particularly affected. Sea temperatures in the western Mediterranean were high compared to the historical average, while the central and eastern regions registered close to average levels, according to the researchers.

During the month of July average temperatures exceeded 24C across almost the entire basin. Temperatures in August remained above typical values for the month and only the Gulf of Lions, off the coast of France, registered close to the average.