Scientific observations show a significant change in the color of the Black Sea. Until recently, images from space showed the sea in a dark blue hue, but now it has acquired a bright emerald hue. This is especially noticeable near the coasts of Bulgaria and Romania, as well as the Danube River Delta.

In May this year, the sea began to change its color, which, according to scientists, was caused by the intense proliferation of phytoplankton. Images obtained from the Aqua satellite show that the color of the water changes from dark blue to bright green.

These transformations were also seen off the Ukrainian coast in early June. Experts warn that such rapid growth of phytoplankton could cause the oxygen level in the water to drop, which could lead to the mass death of marine creatures.

Scientists from NASA believe that these processes are part of annual events, but in May 2024 their intensity increased. These mark the bright, spring bloom of phytoplankton stimulated by a number of factors, including the influence of major rivers such as the Danube, Dnipro, Rioni and Dniester, which flow into the Black Sea and bring nutrients with them.

This proliferation is a result of the high activity of phytoplankton, which consists of microscopic algae and cyanobacteria that feed on sunlight and serve as a food source for fish and shellfish. These microorganisms produce food through photosynthesis using nutrients from chlorophyll and water.

More than 150 species of phytoplankton have been recorded in the Black Sea, contributing to the biodiversity of marine life. Their activities sometimes give rise to huge blooms that can be seen from space and draw unique patterns in the water. Source