Oceans and Water Systems & Resources
Water is the lifeblood of our planet, and it plays a pivotal role in shaping the world's geography and supporting all forms of life. Systems of freshwater and saltwater distribute heat and provide resources across the planet.
Water systems across the planet are interconnected. Saltwater oceans cover over 70 percent of the Earth and are divided into the Atlantic Ocean, Pacific Ocean, Indian Ocean, and Arctic Ocean.
Only about three percent of Earth's water is freshwater and only about one percent is drinkable liquid water.
Water is continuously cycled between the atmosphere, surface water, and underground through a process known as the hydrologic cycle.
The amount of water on Earth remains consistent over time but it goes through different forms: liquid, solid (ice) and vapor.
Water evaporates into the atmosphere from oceans and other bodies of water. Water vapor in the atmosphere eventually cools, condenses, and falls to earth as precipitation. This rain or snow infiltrates into the ground and drains into rivers and other bodies of water where it is recycled.
Oceans are crucial for regulating the planet's climate, providing a habitat for diverse marine life, and serving as a source of transportation and commerce.
Additionally, there are many other forms of water systems that take part in Earth's water cycle.
Seas
Seas are smaller bodies of saltwater that are partially enclosed by land. Examples include the Mediterranean Sea and the Caribbean Sea. Seas are important for fishing, shipping, and tourism, and they often play a role in local cultures and traditions.
Lakes
Lakes are freshwater bodies surrounded by land. They vary in size from small ponds to massive bodies like the Great Lakes in North America. Lakes are essential for providing drinking water, recreation, and supporting aquatic ecosystems.
Rivers
Rivers are freshwater flows that carve their way through the landscape. Water generally collects into a river through surface runoff from precipitation, meltwater released from natural ice and snowpacks, and other underground sources such as groundwater recharge and springs.
The earliest human civilizations developed along rivers and most of the world's major cities are situated on the banks of navigable rivers. They are the primary sources of freshwater for many communities and agriculture.
Rivers also serve as common political boundaries and sources of energy through mills and hydroelectric plants. Rivers like the Amazon, Nile, and Mississippi are vital to the regions they pass through.
Estuaries
An estuary is where a freshwater river meets the sea or ocean. Sometimes called a tidal mouth, estuaries create a unique environment where freshwater and saltwater mix. They are crucial for breeding and nurturing many marine species. Chesapeake Bay is the largest estuary in the United States.
Glaciers
Glaciers are immense ice formations found in polar regions and mountain ranges. Glacial ice has a distinctive blue tint and is the largest reservoir of fresh water on Earth.
Along with ice sheets, they hold about 69 percent of the world's freshwater. As they melt, glaciers provide freshwater for rivers and ecosystems, making them a vital water source.
Glacial mass is one of the most sensitive indicators of climate change. Human activities result in more carbon dioxide and greenhouse gases in the air and result in warming global temperatures. This melts glaciers at a faster rate and can lead to rising sea levels.
Wetlands
Wetlands are areas that are periodically or permanently saturated with water, such as marshes and swamps. They are essential for water filtration, flood control, and supporting diverse wildlife.
Groundwater
Groundwater is water stored beneath the Earth's surface in aquifers. It provides drinking water for many communities and supports agriculture through wells and irrigation.
Water systems offer a wealth of resources that sustain life and shape the human experience. Freshwater is essential for drinking, cooking, sanitation, and agriculture.
Oceans regulate the planet's climate, support diverse ecosystems, and are teeming with aquatic life, providing a rich source of food. Rivers provide transportation, sources of energy, and opportunities for recreation and tourism. Lastly, water often has a profound cultural and spiritual significance in many societies.
While water systems are invaluable, they face increasing threats from pollution, overexploitation, and climate change. It's crucial to conserve our resources for current and future generations. Sustainable water management, pollution control, and combating climate change are essential to protect our planet's liquid treasures.