Why does water boil at 100 degrees Celsius in Melbourne but at a lower temperature in high-altitude locations?

Water boils at 100 degrees Celsius in Melbourne because it is close to sea level, where atmospheric pressure is standard. At higher altitudes, the atmospheric pressure is lower, which reduces the energy required for water molecules to escape into vapor. As a result, water boils at a lower temperature in high-altitude locations. For example, at 2,000 meters above sea level, water boils at approximately 93 degrees Celsius.