Topic Page

Ocean Trenches

February 6, 2019

Ocean trenches are steep depressions exceeding 6,000 meters in depth, where old ocean crust from one tectonic plate is pushed beneath another plate.

Seamounts

Mountains rising from the ocean seafloor that do not reach to the water’s surface.

Natural Oil Seeps

As much as one half of the oil that enters the coastal environment comes from natural seeps of oil and natural gas.

Mid-ocean Ridges

The mid-ocean ridge occurs along boundaries where plates are spreading apart.

Hydrothermal Vents

In 1977, scientists made a stunning discovery on the bottom of the Pacific Ocean: vents pouring hot, mineral-rich fluids from beneath the seafloor.

Marine Microplastics

Marine microplastics are small fragments of plastic debris that are less than five millimeters long. Some microplastics, known as primary microplastics, are “micro” by design

Oil Spills

The systematic study of oil in the ocean is relatively new to science, but since the late 1960s it has grown to encompass almost every area of oceanography.

Fukushima Radiation

On March 11, 2011, a magnitude 9.0 earthquake 80 miles off the northeast coast of Japan triggered a series of tsunamis that struck nearby shorelines and the Fukushima Daiichi nuclear power plant.

Beach Closures

Hundreds of beaches nationwide are closed each year due to the presence of potentially harmful bacteria, viruses, and parasites in the water.

Sea Ice

The U.S. Coast Guard icebreaker Healy moves through pancake ice in the Arctic's Chukchi Sea.

Sea ice is frozen seawater floating on the surface of the ocean. Sea ice is formed entirely in the ocean, unlike icebergs, which originate from land-based sources like glaciers and ice sheets.

Polar Life

By human standards, they are extreme environments. Yet life not only persists in the poles…it thrives.

Glaciers are large ice masses created by snowfall that has transformed into ice and compressed over the course of many years. An ice sheet is a mass of glacial land ice extending more than 20,000 square miles.

Arctic Ocean Circulation

The complex ocean circulation system in the Arctic—which impacts the entire food web—is in a delicate balance.

Seafloor Mining

The ocean contains a complex combination of processes that sometimes result in commercially viable forms of a wide range of minerals.

Marine Protected Areas

Marine protected areas refers to any part of the ocean that receives some level of protection under law, protecting about one percent of the global ocean.

Aquaculture

Aquaculture is the farming in fresh and saltwater environments of aquatic animals or plants principally for food. Fish, mollusks, crustaceans, and kelp are a few examples.

Sharks & Other Fish

Fish serve important ecological and economic functions. Ecologically, they are both predator and prey, providing food for other animals, and serve to keep the numbers of prey species in check, many of which could destroy important ecosystems such as coral reefs and mangroves if their numbers are allowed to grow.