Arctic fjords

Marine

Oceans, Seas & Coral Reefs
GeoNadir
Farquharson Reef
,
Australia

Covering more than two-thirds of the planet and producing almost three quarters of the oxygen that we breathe, it isn’t an exaggeration to say that the Earth’s oceans and seas are the lifeblood that keeps our world turning. From the warm shallows of the Mediterranean to the dark, mysterious depths of the Pacific Ocean, this is a habitat like no other - and one that we’re only just beginning to explore. 

Found in the warm, clear waters of the tropics, within reach of the sun’s rays, coral reefs are some of the most surprising parts of our seas. The most famous coral reef of all is found off the northern eastern coast of Australia. Stretching for over 340,000 square kilometres, across 900 islands, the Great Barrier Reef is home to 1600 species of fish, 134 species of shark, and hundreds upon hundreds of species of plant. It’s a scale that those of us dwelling on the land might find it difficult to fully comprehend. 

The Great Barrier Reef isn’t the only coral reef to be found in our seas, though. From Hawaii and Belize to the Solomon Sea, the aquatic habitats found just under the surfaces of our warmest waters contain a rich marine life that remains mysterious to many of us. Supporting 25% of all marine life whilst only making up 1% of the ocean’s floor, these coral reefs are working hard to protect our below sea habitats. 

Absorbing 50 times more carbon than the atmosphere and regulating our temperature and weather through their distribution of heat between the north and south poles, the planet’s oceans and seas are quietly performing the work needed to maintain life on Earth.

Biome Map Image
Terpsichores, CC BY-SA 3.0, via Wikimedia Commons / modified from original

Marine characteristics

  • Salt water 
  • Waves and tides 
  • Surface currents 
  • Vast variation in temperature, depending on depth  
  • Coral polyps 
  • Algae and seaweed 
  • Large variation in fish, aquatic mammal and plant species
Wakatobi, South East Sulawesi
Benjamin L. Jones
Wakatobi, South East Sulawesi
,
Indonesia
Marine climate
Temperature High
38
°C
Temperature High (Avg)
Temperature Low
-40
°C
Temperature Low (Avg)
Precipitation
2540
mm
Precipitation (Avg)

Climate Change

It’s no secret that the delicate ecosystems of our coral reefs are under threat, with warming waters causing large scale bleaching events, pollution lowering the quality of sea water, and coastal developments threatening biodiversity. With all of these things likely to become more prevalent in the future, practical solutions are needed in order to maintain the sanctity of these natural wonders for centuries to come. 

Pollution caused by industry and agriculture, as well as climate change, are also threats to our oceans on a wider scale. Chemicals and sewage are making their way into the world’s oceans, causing the destruction of many of the plants and animals that have previously thrived in these habitats. In shallower waters, sea habitats are at risk from coastal erosion, overfishing, and plastic pollution.

Top Marine trips

For those ready to either take to the water or venture underneath it, there are multiple ways to explore our oceans and coral reefs. Scuba diving and snorkeling are top activities for those looking to immerse themselves in the otherworldly ambience of the reef, looking out for turtles and other sea-dwellers as they bob through the shallow waters. 

For those who prefer to stay above ground, our seas are primed for wildlife spotting from the deck of a sailing boat. Whales, dolphins, seals and sharks can often be glimpsed just off-shore, providing an insight into what might be going on just feet below. 

Of course, sailing itself is another way to explore the seas. Countries with multiple islands, such as Greece, Croatia or Indonesia, can be great locations from which to charter a boat and set out on your way. Coastal locations such as California or the USA’s Pacific Northwest are also good options for this.   

Arctic fjords
Bart van meele
Arctic fjords
,
Norway

Marine areas of natural beauty

Coral reefs are some of the most wondrous natural phenomena on Earth, with the Great Barrier Reef leading the pack as the largest and most photographed. Other reefs shouldn’t be overlooked, though: eastern Indonesia's coral reefs are teeming with biodiversity, whilst Fiji, home to the Cakaulevu Reef, has been called the soft coral capital of the world.

Wildlife

Marine animals

Our oceans, seas and coral reefs are home to over 228,000 species, with predictions saying that there could be up to two million more that we don’t yet know about. Sharks, rays, whales, dolphins, turtles, multiple species of fish, shellfish, invertebrates and seabirds all exist in our oceans, but the true extent of life in the waters that surround us is, quite literally, unknowable.

Marine plants

There are different types of aquatic plants, found at different depths of our seas and oceans. Most (like algae and plankton) need light in order to photosynthesise, so are found in shallow waters. There are no plants on the beds of our deepest oceans. In general, marine ecosystems include seaweed, kelp, algae, corals, phytoplankton and seagrass.

Marine countries

With oceans and seas covering so much of the planet, there are multiple countries that offer adventurers the chance to venture out into the open ocean. Australia, Indonesia, Fiji, The Philippines, Hawaii and The Seychelles all come out on top for those looking to explore the aquatic habitat of the coral reef.