The earth we live on has experienced 4.6 billion years of vicissitudes. Approximately 4.4 billion years ago, the ocean emerged. The formation of the ocean is a complex physical process, but the reasoning behind it is simple.

First, the formation of an ocean requires a large low-lying area, the seabed. The seabed's formation is related to the difference in the crustal rocks that make up the seabed and land.

The rocky layers holding up the sea floor are mostly denser basalts, while the rocks holding up the land are mostly lower-density granites.

Because they all float on the high-temperature liquid mantle. The denser basalt naturally sank deeper, creating a seabed that is at a certain height difference from the continents. Secondly, another indispensable element to form the ocean is seawater.

Regarding the source of seawater, the current hypothesis holds that: in the early days of the earth's evolution, seawater mainly came from numerous comets or asteroids that hit the earth. The other part comes from the interior of the earth, and they are "released" in the form of volcanic eruptions.

In the subsequent long evolution process, the movement of continental plates has driven our land and oceans to be in a state of change. From the "Pangaea" 250 million years ago to today's seven continents and four oceans. Moreover, they are still constantly changing.

The ocean plays a pivotal role in shaping Earth's climate. As the largest reservoir of heat on the planet's surface, it exerts a profound influence on atmospheric dynamics. Ocean currents, acting as colossal conveyor belts of heat energy, redistribute warmth across the globe, regulating temperature patterns and weather phenomena.

The exchange of gases between the ocean and the air (the most important of which are water vapor, carbon dioxide, and methane) has a great influence on the change and development of climate.

The ocean is the living environment of many plants and animals. Green algae in the ocean are one of the main producers of oxygen in the atmosphere. Tropical coral reefs are the most species-rich ecosystems on Earth (even more so than tropical rainforests).

\The ocean has many animals and plants that are not found on land, and there are more types than on land. However, humans still know very little about deep-sea life.

Sea levels have risen by an average of 10-25 centimeters over the past 100 years, and scientists expect this rate to rise further. Even if the climate stabilizes, sea levels will continue to rise because the oceans are slow to respond to change. Ten thousand years ago, the sea level was about 110 meters lower than it is now. If all the ice melted, the oceans would rise 66 meters.

The ocean regulates and provides valuable services and resources worth approximately $300 billion per year. To realize the 2050 vision of living in harmony with nature and to achieve the Sustainable Development Goals, careful and effective ocean management is paramount.

Countries around the world must recognize the urgent need to conserve, protect and sustainably use marine biodiversity.