Oceans

Oceans are the lifeblood of planet earth. Oceans regulate the climate, produce oxygen, and support a rich diversity of life. 

The ocean is a vast and complex ecosystem that covers more than 70% of the Earth's surface. It is home to millions of species of plants, animals and from microscopic plankton to gigantic whales, as well as important natural resources and processes that support life on land. 

Features of Oceans:

We will explicate some of the features of oceans that make them so fascinating and important.

    Depth:

One of the most striking features of the ocean is its depth. The average depth of the ocean is about 3,700 meters, but some parts are much deeper. The deepest point in the ocean is the Mariana Trench, which reaches a depth of 10,994 meters. That's more than the height of Mount Everest! The depth of the ocean affects many aspects of its physical and biological characteristics, such as temperature, pressure, light, and sound.

    Salinity:

Another feature of the ocean is its salinity, or the amount of salt dissolved in the water. The average salinity of the ocean is about 35 grams per liter, but it varies depending on location and season. Salinity influences the density and buoyancy of seawater, as well as its freezing point and chemical composition. Salinity also affects the distribution and adaptation of marine organisms, as some species can tolerate higher or lower salinity levels than others.

    Currents:

A third feature of the ocean is its currents, or the movement of water in different directions and speeds. Currents are driven by various factors, such as wind, gravity, tides, and differences in temperature and salinity. Currents play a vital role in transporting heat, nutrients, oxygen, and carbon dioxide across the ocean, as well as influencing weather patterns and climate. Currents also affect the migration and dispersal of marine life, as some species use currents to travel long distances or find food.

These are just some of the features of the ocean that make it a unique and dynamic system. The ocean is constantly changing due to natural and human-induced factors.

Tides, Waves & Currents:

Tides, waves and currents are natural phenomena that affect the movement of water on Earth. We will explain what they are, how they are formed and why they are important for marine life and human activities.

Tides are the periodic rise and fall of the sea level caused by the gravitational attraction of the moon and the sun on the Earth. Tides have a cycle of about 12 hours and 25 minutes, which means that there are two high tides and two low tides every day. The height of the tides depends on the position of the moon and the sun relative to the Earth, as well as the shape of the coastline and the depth of the water.

Waves are the undulations of the water surface caused by the transfer of energy from the wind to the water. Waves have different characteristics, such as wavelength, amplitude, frequency and speed, depending on the strength and duration of the wind, the distance over which it blows and the depth of the water. Waves can travel long distances across oceans, but they lose energy as they encounter obstacles, such as islands, reefs or shorelines.

Currents are the continuous flow of water in a specific direction caused by various factors, such as temperature, salinity, wind, perpendicular force produced by rotating frame of reference and tides. Currents can be classified into surface currents and deep currents, depending on their depth. Surface currents are driven by wind and affect the upper 10% of the ocean water. Deep currents are driven by density differences and affect the lower 90% of the ocean water. Currents play a vital role in transporting heat, nutrients, oxygen, carbon dioxide and organisms around the globe.

Sea Vs Ocean:

We will explore some of the common features and distinctions that make these two terms not interchangeable.

First of all, what is the sea? A sea is a saltwater body that can be either totally enclosed by land, like the Caspian Sea, or a component of a larger ocean, like the Mediterranean Sea. Seas are generally smaller than oceans in terms of geography and volume. They are also more influenced by the surrounding landmasses, which affect their climate, salinity, biodiversity and human activities. Some of the largest seas in the world are the American Mediterranean Sea, Philippine Sea, Coral Sea, Arabian Sea and Sargasso Sea.

What about the ocean? The ocean is the largest saltwater body on the planet, covering more than 70% of its surface and containing 97% of its water. The ocean is divided into five major regions: the Pacific Ocean, Atlantic Ocean, Indian Ocean, Arctic Ocean and Southern Ocean. The Pacific Ocean is the largest and deepest ocean, while the Arctic Ocean is the smallest and shallowest. The ocean is an integral part of life on Earth, as it regulates the climate, weather patterns, carbon cycle and oxygen production. The ocean is also home to a vast array of marine life forms, from microscopic plankton to gigantic whales.

Similarities between the sea and the ocean:

So what are some of the similarities between the sea and the ocean? Here are some points to consider:

- Both sea and ocean are saltwater bodies that have tides. Tides are long waves that travel across the water due to the gravitational pull of the moon and the sun. Tides affect the water level, currents, waves and coastal erosion of both sea and ocean.

- Both sea and ocean are connected to each other and form part of the global ocean system. The global ocean system is a network of interconnected water bodies that circulate water, heat, salt, nutrients and organisms around the planet. The global ocean system consists of four main components: surface ocean, deep ocean, polar oceans and marginal seas.

- Both sea and ocean support life and are part of the carbon cycle. The carbon cycle is the process by which carbon moves between different reservoirs on Earth, such as the atmosphere, land, plants, animals and water. The sea and the ocean play a crucial role in absorbing carbon dioxide from the atmosphere and storing it in organic matter or sediments. They also produce oxygen through photosynthesis by marine plants and algae.

Differences between the sea and the ocean:

As you can see, there are many similarities between the sea and the ocean that make them both essential for life on Earth. However, there are also some differences that make them distinct from each other. Here are some examples:

- The sea is smaller than the ocean in terms of area and volume. The sea covers about 7% of Earth's surface and contains about 0.05% of its water. The ocean covers about 71% of Earth's surface and contains about 97% of its water.

- The sea is more influenced by land than the ocean. The sea is often surrounded by land or connected to it by narrow straits or channels. This means that the sea is more affected by factors such as climate, rainfall, river runoff, evaporation, pollution and human activities than the ocean. The sea also has more variations in salinity, temperature and biodiversity than the ocean.

- The sea has different names than the ocean. The sea is usually named after its location or characteristics, such as Baltic Sea, Red Sea or Dead Sea. The ocean is usually named after its position or direction relative to other continents or oceans, such as Pacific Ocean, Atlantic Ocean or Indian Ocean.

In conclusion, the sea and the ocean are both saltwater bodies that have many similarities in terms of their functions and roles on Earth. However, they also have some differences in terms of their size, shape, influence and names that make them unique from each other.

Functions of Oceans:

The ocean provides many functions that support life on Earth and human well-being. We will explore some of the main functions of the ocean and why they are important for us.

    Oxygen:

One of the most obvious functions of the ocean is to produce oxygen. The ocean is home to millions of microscopic plants called phytoplankton, which use sunlight and carbon dioxide to make their own food and release oxygen as a by-product. Phytoplankton are responsible for about half of the oxygen we breathe, making them essential for our survival.

    Regulation of Climate:

Another function of the ocean is to regulate the climate. The ocean absorbs a lot of heat from the sun and distributes it around the world through currents and winds. This helps to moderate the temperature extremes between different regions and seasons. The ocean also acts as a carbon sink, absorbing some of the excess carbon dioxide that humans emit into the atmosphere. This helps to slow down the rate of global warming, but also causes ocean acidification, which threatens marine life.

    Food & Resources:

A third function of the ocean is to provide food and resources. The ocean is a rich source of fish, shellfish, seaweed, and other edible products that feed billions of people around the world. The ocean also contains minerals, metals, oil, gas, and other valuable materials that can be extracted for various purposes. 

    Biodiversity:

A fourth function of the ocean is to support biodiversity. The ocean is the most diverse and complex ecosystem on Earth, hosting millions of species of animals and plants, from microscopic bacteria to giant whales. The ocean also connects different habitats and regions, allowing for the exchange of genes and nutrients. The ocean also provides many ecosystem services, such as pollination, pest control, water purification, and coastal protection.

    Transportation:

Ocean transport is a vital mode of transportation for international trade and commerce. It enables the movement of goods and commodities across large distances and geographical barriers, connecting different markets and regions. Ocean transport has many advantages, such as low cost, high capacity, environmental friendliness, and flexibility.

These are just some of the main functions of the ocean that benefit us and our planet. 

Ocean Zones:

The ocean is not a uniform body of water, but rather a dynamic and diverse environment that varies in temperature, salinity, depth, and chemistry. The ocean can be divided into different zones based on these factors, such as:

• The surface zone, where sunlight penetrates and photosynthesis occurs; 
• The twilight zone, where light fades and bioluminescence becomes more common; 
• The midnight zone, where darkness prevails and pressure increases; and 
• The abyssal zone, where the seafloor lies, and extreme conditions exist.

What if there are no oceans?

Some of the consequences of a world without oceans are:

- The global temperature would be more extreme, with hotter days and colder nights. The oceans act as a heat buffer, absorbing and releasing heat depending on the season and latitude. Without oceans, there would be no ocean currents or winds to distribute heat around the globe, leading to more temperature variations and less habitability.

- The atmosphere would have less moisture and more carbon dioxide. The oceans are a major source of water vapor, which forms clouds and precipitation. Without oceans, there would be less rainfall and more droughts, affecting agriculture and freshwater availability. The oceans also absorb about 25% of the carbon dioxide emitted by human activities, reducing the greenhouse effect and mitigating climate change. Without oceans, the carbon dioxide concentration in the atmosphere would increase, enhancing the greenhouse effect and warming the planet.

- The biodiversity would be reduced, and many species would go extinct. The oceans are home to millions of species, from microscopic plankton to giant whales. Many of these species are endemic to specific regions or habitats, and depend on the oceans for food, shelter, reproduction, and migration. Without oceans, many marine species would die out, along with terrestrial species that rely on them for food or other services. The loss of biodiversity would have negative impacts on ecosystem functioning and human well-being.

Conclusion:

Oceans are large bodies of salt water that cover about 71% of the Earth's surface and contain 97% of its water. Oceans are vital for life on Earth as they regulate climate, the carbon cycle, and the water cycle, produce oxygen, provide food and resources. They also support a rich diversity of life, from microscopic algae to giant whales.  

Points to Ponder:

What would happen if there were no currents?

Oceans are a huge body having immense life and supportive functions, how can they function efficiently without a central command and control?