In 2023, the world’s oceans experienced a catastrophic series of marine heatwaves (MHWs), reaching unprecedented levels of intensity, duration, and geographic spread. Understanding Marine Heatwaves: The Basics and Their ConsequencesMarine heatwaves (MHWs) are prolonged periods when ocean temperatures rise significantly above normal levels. Additionally, marine heatwaves disrupt food chains, as many species of fish and marine organisms are highly sensitive to temperature fluctuations. The Underlying Causes of Marine Heatwaves: A Complex Interaction of Climate ForcesSeveral factors contributed to the unprecedented marine heatwaves in 2023. The Connection Between Marine Heatwaves and Broader Climate ChangeThe intensity and frequency of marine heatwaves in 2023 are deeply connected to broader shifts in the Earth’s climate system.