Hydrosphere
The Hydrosphere is a discontinuous layer of water at or near earth's surface that includes oceans, glaciers and ice sheets, ground water and perma frost, lakes, rivers, and the plants and animals that live within.
Oceans makes up 97.5% of the Hydrosphere and the remaning 2.5% is fresh water, where of 68.7% is galciers, 30.1% is ground water and 0.8% is perma frost. The total volume of liquid water on Earth has been calculated to be around 1.39 billion cubic kilometer or 332.5 million cubic miles. On average, the water on earth has a temprature of around 4 °C or 39.2 °F, just above the freezing point of water.
Earth's Water Cycle
The water cycle, also known as the hydrologic cycle, is the continuous movement of water between the Earth's surface and the atmosphere. It involves several processes, including evaporation, transpiration, condensation, precipitation, and infiltration.
Evaporation is the process by which water changes from a liquid to a gas or vapor, and it occurs when the sun heats up water bodies such as oceans, lakes, and rivers. Transpiration is the process by which water vapor is released into the atmosphere by plants.
Condensation occurs when water vapor in the atmosphere cools and forms tiny droplets of liquid water, which then combine to form clouds. Precipitation occurs when these water droplets become large enough to fall to the ground as rain, snow, sleet, or hail.
Once precipitation falls to the ground, it may either evaporate back into the atmosphere, flow into rivers and streams, or percolate through the soil and rock layers to become groundwater. Groundwater may eventually flow back to the surface as springs, or it may be extracted by wells.
Overall, the water cycle is a vital process that sustains life on Earth by ensuring a constant supply of fresh water for plants, animals, and humans. However, changes in the Earth's climate can have significant impacts on the water cycle, leading to droughts, floods, and other extreme weather events.
Humans & the Hydrosphere
Humans make extensive use of the hydrosphere, which includes all of the water on Earth, including oceans, lakes, rivers, groundwater, and glaciers.
- Drinking water: Freshwater from rivers, lakes, and groundwater is treated and used for drinking and cooking.
- Irrigation: Water from rivers, lakes, and groundwater is used for irrigation to grow crops.
- Transportation: Oceans, lakes, and rivers are used for transportation of people and goods by ships and boats.
- Energy production: Water is used to generate hydroelectric power by using turbines that are turned by the force of moving water.
- Fishing: Oceans, lakes, and rivers are used for fishing, which provides a source of food and livelihood for many people.
- Recreation: People enjoy swimming, boating, and other water-based activities for leisure and recreation.
- Industrial use: Water is used in many industrial processes, such as cooling and cleaning.
However, human activities can also have negative impacts on the hydrosphere, such as pollution from industrial and agricultural activities, overuse of groundwater resources, and climate change, which can lead to rising sea levels, ocean acidification, and changes in precipitation patterns. Therefore, it is important to manage our use of the hydrosphere sustainably to ensure that it remains healthy and provides for the needs of future generations.
Articles & Papers
Snippets of articles and papers written about the subject of Global Sea Level from aroud the web
Climate Change: Global Sea Level
Global mean sea level has risen about 8–9 inches (21–24 centimeters) since 1880, with about a third of that coming in just the last two and a half decades. The rising water level is mostly due to a combination of melt water from glaciers and ice sheets and thermal expansion of seawater as it warms. In 2020, global mean sea level was 91.3 millimeters (3.6 inches) above the 1993 average, making it the highest annual average in the satellite record (1993-present).
Source: 🇺🇸 climate.gov