How Do Dark Streams of Arctic Glacial Meltwater Affect Plankton?

Abstract

In the last decades, the temperatures of Earth’s atmosphere and its oceans have increased significantly. Warming strongly affects the Arctic, where we can observe fast glacial melt during the summer. Meltwater brings debris from the land into the coastal ocean, creating zones with brown water. This seawater darkening can affect the living conditions of marine organisms and possibly threaten marine life in the future. To address this issue, we studied the particles that make the seawater dark and the effect that seawater darkening has on the tiny plants and animals in the coastal waters of the European Arctic. Open, clear waters were greenish and full of life, while in muddy brown zones, we observed intensive “snowstorms” of particles. Our study taught us about how marine organisms interact with these particles. Based on our observations, we can design computer models to help us predict the fate of the coastal waters in a future, warmer Arctic.