What a beatiful day!
Also known as the sunlight zone, the epipelagic zone is where most of the visible light exists. Due to heat from this light, there are wide variations in temperature across this zone, with sea surface temperatures ranging from as high as 36°C to -2°C.
Sometimes referred to as the twilight zone or the midwater zone, as sunlight this deep is very faint. Temperature changes are the greatest in this zone because it contains the thermocline, a region where water temperature decreases rapidly with increasing depth, forming a transition layer between the mixed layer at the surface and deeper water.
Going down...
Getting deeper!
This zone is in constant darkness and is often called the midnight zone. The only light source at this zone and beyond is from bioluminescent animals. The temperature here is constant at around 4°C. Sperm whales can dive down to this level in search of food in spite of the great pressure here.
The water temperature is constantly near freezing in this zone, and only a few creatures can be found at these crushing depths. The name (abyss) comes from a Greek word meaning "no bottom" because they thought the ocean was bottomless. Three-quarters of the area of the deep-ocean floor lies in this zone.
Down, down, down...
Keep going!
You can do it!
The deepest part of the ocean is in the Mariana Trench off the coast of Japan. The temperature is constant, at just above freezing. The weight of all the water over head in the Mariana Trench is over 8 tons per square inch.
Made it!