Anomalous Phenomena in the Development of Phytoplankton in the Black Sea on the Basis of Remote Sensing Data

Abstract

Anomalous phenomena in the development of phytoplankton in the Black Sea for the period of 2000–2020 have been recorded on the basis of satellite data. Anomalous summer blooms of diatoms were detected in the field of chlorophyll a for the blooming periods of 2001, 2010, and 2015. These blooms were unusual for the summer periods and developed under conditions of a negative anomaly in the surface layer temperature caused by active wind mixing. The highest level of development of summer blooms of coccolithophore was recorded in 2006, 2012, and 2017. These phenomena have been observed after abnormally cold winters. It has been shown that in some years, under conditions of low summer temperatures and active wind mixing, the summer vegetation of coccolithophores is poorly manifested and can be replaced by the development of diatoms. Satellite data over a twenty-year period demonstrated numerous signs of mass development of coccolithophores during the cold season. Winter blooms of coccolithophorids occur in warm winters with low wind activity. It has been noted that after the winter blooms of coccolithophores, their summer vegetation is largely smoothed. The influence of hydrometeorological factors on the seasonal and interannual variability of phytoplankton is discussed.