In the period 1960-2019, the mean sea level along the Slovenian coast increased by 11 cm. On average, this means by 1.8 mm/year and in the last 20 years by 4,4 mm/year. It is estimated that the increase of the middle sea level is affected by global see level increase, and in the last period also by extreme weather conditions in the region. In the last twenty years, at the Slovenian and in the Adriatic coast sea level has been rising faster than the European and global trends.

Phytoplankton biomass, expressed as chlorophyll a concentration, reflects nutrient loading in the marine environment. Chlorophyll a concentrations shows a trend towards improvement in the status of the Slovenian sea, as the ecological status has been assessed as high or good over the last period.

The quality of bathing water along the Slovenian coast is excellent, which ranks Slovenia at the top among the EU countries.

Nutrients, especially nitrogen and phosphorus compounds, are important for the growth of algae and higher plants, but in high concentrations can cause undesirable changes in aquatic organisms and seawater quality. Long-term measurements of selected nutrients in the Slovenian sea show that their concentrations have decreased significantly. Therefore, the ecological status of the Slovenian Sea is assessed as good to very good based on nutrients in recent years.