Oceans darkened, endangering marine life globally since 2003

Ocean waters have darkened by over 21% since 2003, shrinking light zones and threatening marine life that depends on sunlight. The darkening, affecting an area larger than 75 million square kilometers, reduces the depth of photic zones, where most marine life thrives, according to a new study. Light penetration has decreased by over 50 meters in around 9% of the ocean. Factors include agricultural runoff and warming sea temperatures, which promote plankton blooms and alter algae growth. This shift could disrupt ecosystems and impact fisheries and climate regulation.