Layers of the water column

The water column is a way of describing the different features found in seawater at different depths.  Scientists use these descriptions to classify how deep a section of the ocean is anywhere in the world.

Water column layers

The diagram below shows the layers of the ocean to a scale of 1 pixel to 10 meters.  To give an idea of the scale, a two storey house is around 1 pixel high or the size of a full stop.  At the bottom you can see how tall some famous buildings and places compare to the depths of the ocean.

Surface - 200m the Epipelagic zone

The only zone where enough sunlight reaches to support plant life, ideal for 90% of all ocean life. Also called sunlit or euphotic zone.

200m - 1000m the Mesopelagic zone
Light at this depth is faint and there is not enough to support photosynthesis. Animals at this depth include octopus, squid and hatchet fish. Some fish have extra large eyes to see and others produce their own light, called bio-luminescence. Also known as the midwater or twilight zone.

1000m - 4000m the Bathypelagic zone
No light penetrates this deep, so it is extremely cold and completely dark. About 1% of all ocean species lives in this zone. The sperm whale can dive to these depths searching for food, and might find giant squid, angler fish, gulper eel or snake dragon fish. Also known as the midnight zone.

4000m - 6000m the Abyssopelagic zone
Also known as the Abyss the name for this zone comes from the Greek word meaning 'no bottom', but actually three quarters of the ocean floor lies within this zone. Water temperatures border on freezing and there is no light. Very few creatures live this deep, but there are tiny squid and a few other small invertebrates.

6000m - 10,000m the Hadalpelagic zone
This zone is mostly composed of canyons and trenches. The deepest point in the ocean is in the Mariana Trench, off Japan, at 10,911m (35,797 feet). Despite the enormous pressure of around 1.1 tonnes per square centimetre (8 tons per square inch), life still exists here - flat fish were spotted on the first manned mission and invertebrates such as starfish and tube worms have also been seen.



Tag(s)

Home | Back to top


Information for…

Business

The outputs of research generate new knowledge about the oceans. Transferring scientific knowledge to support business and industry is an important part of our NOC remit.

More

Researchers

Our research is intended to tackle the big environmental issues facing the world. Research priorities will include the oceans' role in climate change, sea level change and the future of the Arctic Ocean.

More

Students

The University of Southampton and the University of Liverpool both offer a range of highly regarded undergraduate and post-graduate degrees in Ocean and Earth Science.

More

Media

For any media or press enquiries to the National Oceanography Centre follow the more link below. Please note the centre's press office is staffed from 0830 to 1730, Monday to Friday.

More

Staff

NOC Staff can access the Intranet and Webmail resources at the following URLS.

Everyone

Follow what we are up to:

Follow NOCnews on Twitter Follow NOCSnews on Youtube Follow NOC on facebook

Delivery Partners

Delivery Partners helping to provide marine science national capability.

More

Marine Science Community

The creation of a wider association of Universities and research institutions to support wider engagement of the NOC with the marine science community is now underway.

More 

Library

The National Oceanographic Library is a national resource for the UK marine science community.

More 

Principal scientists

All updated information for cruise participants can be found using the Marine Facilities Planning website:

More