Cold upwelling on Romania's Black Sea coast disrupts summer tourism

Lifeguards raised a red flag on beaches in Eforie Nord, prohibiting swimming after strong waves and currents made the sea dangerous. Authorities urged tourists to stay out of the water until conditions improve.

Temperatures of the Black Sea fell sharply this week, reaching as low as 13 °C in Mamaia and about 18 °C in Mangalia, prompting many visitors to stay on the sand. Experts explained the rapid cooling as an upwelling event, where wind pushes surface water offshore and cold, nutrient‑rich water rises from depth.

While the sudden cold caused discomfort for holiday‑makers, the upwelling also benefits the marine ecosystem by delivering nutrients that stimulate plankton growth and attract fish. The phenomenon is usually short‑lived, lasting 24‑48 hours before sea temperatures return to normal.

Tourist operators and local businesses are monitoring the situation as the brief cold spell may affect attendance at seaside resorts this summer.