Water Water is one of the most important natural resources for life on Earth. It is not only essential for the survival of human beings, but also for all ecosystems on the planet. Water plays a fundamental role in agriculture, livestock, industry and, of course, in our daily lives for activities such as drinking, showering and cooking. This leads to water being recognized not only as a vital resource, but as a regulator of the climate and modulator of planetary life. In addition, from a scientific point of view, water is part of a larger system called hydrosphere.
The hydrosphere includes all the water present on Earth and it exists in three states: solid, liquid and gas. This global water system continuously interacts with other components of the Earth, such as the atmosphere, lithosphere and biosphere, all of which are interrelated and vital to maintaining the ecological and climatic balance of the planet. In this article we will explain what exactly the hydrosphere is, how it was formed, its composition, distribution and the fundamental importance it has, not only for life, but for the climate and biodiversity of the Earth.
What is the hydrosphere
La hydrosphere The hydrosphere is the set of all the water that exists on the planet, both in its liquid and solid and gaseous state. In addition to oceans, seas, lakes and rivers, the hydrosphere includes groundwater, glaciers, soil moisture, and even water vapor present in the atmosphere. This dynamic system is in constant movement thanks to the water cycle, which makes it a key element in the regulation of the Earth's climate.
As for its distribution, the hydrosphere covers approximately 71% of the Earth's surface, with an average depth in the oceans of around 3,5 kilometers. However, despite its extension, only the 3% Of all the water in the hydrosphere is fresh water, and of that percentage, less than 1% is accessible for human consumption.
One of the most important aspects of the hydrosphere is its ability to interact with other spheres of the planet. For example, water dissolves and transports minerals from the lithosphere, regulates temperature in the atmosphere and is essential for life in the biosphere. Its interaction with the Earth's crust through processes such as erosion and sedimentation also contributes to shaping the planet's relief and geography.
Origin of the hydrosphere
The origin of the hydrosphere is closely linked to the process of the formation of the Earth. Approximately 4.500 billion years ago, our planet was a glowing ball of rock and water in the form of vapour due to high temperatures. As the Earth cooled, the water vapour condensed, giving rise to thick layers of clouds that subsequently precipitated as intense rain for millions of years. This is how the first bodies of water such as seas and oceans were formed.
The cooling of the Earth's surface not only allowed the formation of liquid water, but also solid water in the form of glaciers and polar ice caps. At the same time, large amounts of water vapor were trapped in the atmosphere, which initiated the process known as water cycle, a constant cycle of evaporation, condensation and precipitation that continues today.
In addition to physical and chemical dynamics, the interaction between the hydrosphere and biology has been crucial to its evolution. Marine organisms, plants, and humans have influenced the composition and distribution of water throughout Earth's history. Today, human activity, together with climate change, is altering the water cycle in worrying ways, affecting rainfall patterns, the distribution of glaciers, and the availability of drinking water.
Composition by parts
The hydrosphere can be divided into three large groups depending on the states of the water:
- Solid water: It comprises the frozen part of the water, mainly present in polar caps, alpine glaciers and ice floes, forming what is known as the cryosphereThe cryosphere is essential for the planet's thermal regulation, as it reflects much of the solar radiation, helping to moderate global warming.
- Liquid water: Liquid water is found in rivers, lakes, lagoons, oceans and seas. It also includes groundwater that forms part of aquifers and streams. This category comprises approximately 97% of the Earth's total water reserves, although it is mostly salt water.
- Carbonated water: Water in a gaseous state is found in the atmosphere as water vapor. This state is essential for the hydrological cycle, since water vapor is responsible for the formation of clouds and, eventually, precipitation.
Distribution and contamination of water on the planet
Water on Earth is distributed unevenly. Most of it, about 100%, is distributed 97%, is contained in the oceans and seas. Only the 2,5% of water is fresh water, and of this, almost the 70% is trapped in solid state in ice caps and glaciers. Less than 1% of all fresh water is accessible for human consumption, which puts into perspective the importance of this resource and the need for its conservation.
One of the biggest problems facing the hydrosphere today is the water contamination, largely caused by human activity. From dumping chemicals and plastics into the oceans to polluting rivers and aquifers with toxic substances, humans have severely altered water quality in many regions of the world.
Major pollutants include:
- Bacteria, viruses and parasites: These biological contaminants can make water unsafe for human consumption.
- Chemical products: Such as fertilizers, pesticides and industrial products that reach bodies of water through runoff, affecting entire ecosystems.
- Plastics: Microplastics are a growing threat as they are ingested by aquatic animals and can eventually enter the human food chain.
- Heavy metals: Elements such as mercury and lead are highly toxic and can accumulate in water to dangerous levels.
Global warming is also exacerbating problems in the hydrosphere. As temperatures rise, glacier melting is accelerating, rainfall patterns are changing, and extreme weather events such as floods and droughts are becoming more common. These disruptions have a direct impact on freshwater availability and global food security.
Despite the amount of water on the planet, the proportion suitable for human access is extremely limited. Addressing water pollution and climate change is essential to ensure the survival of humanity and other life forms that depend on good quality water. Although technologies such as desalination and wastewater purification exist, these solutions are currently expensive and create other problems such as high energy consumption.
In short, water care must be a priority. From pollution prevention to sustainable water resource management, every country and every individual must commit to overseeing how one of the planet's greatest resources is used and protected: water.