Earth's tides are not only influenced by the Moon, but also by the Sun and other factors, and they are changing as the planet warms. While some regions experience only minor tidal changes, others see dramatic differences between high and low tides. For example, along Western Australia’s Kimberley coast, the tidal range can exceed 10 meters (33 feet). Tides shape coastlines, influence marine life, and even affect the melting of Antarctic ice shelves, making them an important factor in both natural and human systems. Tides are primarily caused by the gravitational pull of the Moon and the Sun on Earth’s oceans. Although the Sun is much more massive, the Moon’s closer proximity gives it a stronger influence on tides. The Moon’s gravity pulls more strongly on the side of Earth facing it and less strongly on the opposite side, creating two tidal bulges—one on the near side and one on the far side. As Earth rotates, different parts of the planet pass through these bulges, resulting in the familiar pattern of two high tides and two low tides each day. The Sun also contributes to tides, though its effect is weaker. When the Sun, Moon, and Earth align, their gravitational forces combine, creating larger-than-normal tides called spring tides. When the Sun and Moon are at right angles relative to Earth, their effects partially cancel each other out, resulting in smaller tides known as neap tides. However, the actual tides measured at coastlines and by satellites are more complex than the simple two-bulge model suggests. Continents and the shape of ocean basins cause tides to move in more complicated patterns. In many areas, tides rotate around points where the tidal rise and fall is minimal—called amphidromic points. Tidal ranges tend to be larger farther from these points. Coastal features like bays can further amplify tides through a process called resonance, where the natural movement of water matches the rhythm of the tides. This effect is responsible for the extreme tides seen in places like the Kimberley coast and Canada’s Bay of Fundy. Underwater mountains and ridges also play a role in shaping tides. When tides move over rough seafloor, some of their energy is converted into internal tides—waves that move within the ocean rather than on the surface. These internal tides can drive ocean mixing and the distribution of heat and nutrients. Recent research has shown that including the effects of these internal tides in models can improve the accuracy of tide predictions without requiring complex simulations. This could lead to better models for understanding past and future tides, and their impact on Earth’s systems. Climate change is causing sea levels to rise and altering ocean conditions, which may be changing tides in ways that are already being observed. Improved models and new satellite technology are helping scientists study tides in complex coastal areas more effectively. For communities like Lakes Entrance in Victoria, Australia, where rising tides have led to increased flooding, understanding these changes is critical. Local authorities are now seeking funding for infrastructure improvements to protect homes and businesses, highlighting the growing importance of accurate tide predictions for coastal planning and safety.