Final answer:
Water's high specific heat is the property that helps regulate temperature on Earth by allowing it to absorb or release large amounts of heat with minimal temperature change, stabilizing the environment.
Step-by-step explanation:
The property of water that helps to regulate temperature on Earth is its specific heat. Water requires an unusually large amount of energy to change temperature. This means that water can absorb or release large amounts of heat energy with only a small change in actual temperature.
Due to its high specific heat, water stabilizes temperature changes in the environment, acting as a thermal buffer. This is vital in maintaining stable ecosystems and climate conditions on Earth.