ESS2.C The Roles of Water in Earth’s Surface Processes

• Water is found in the ocean, rivers, lakes, and ponds. Water exists as solid ice and in liquid form.
• Nearly all of Earth’s available water is in the ocean. Most fresh water is in glaciers or underground; only a tiny fraction is in streams, lakes, wetlands, and the atmosphere.
• Water continually cycles among land, ocean, and atmosphere via transpiration, evaporation, condensation and crystallization, and precipitation, as well as downhill flows on land.
• The complex patterns of the changes and the movement of water in the atmosphere, determined by winds, landforms, and ocean temperatures and currents, are major determinants of local weather patterns.
• Global movements of water and its changes in form are propelled by sunlight and gravity.
• Variations in density due to variations in temperature and salinity drive a global pattern of interconnected ocean currents.
• Water’s movements—both on the land and underground—cause weathering and erosion, which change the land’s surface features and create underground formations.
• The abundance of liquid water on Earth’s surface and its unique combination of physical and chemical properties are central to the planet’s dynamics. These properties include water’s exceptional capacity to absorb, store, and release large amounts of energy, transmit sunlight, expand upon freezing, dissolve and transport materials, and lower the viscosities and melting points of rocks.