Tag: Basics

Natural History / Natural History - 6 months ago

What is a watershed?

While some watersheds are relatively small, others encompass thousands of square miles and may contain streams, rivers, lakes, reservoirs, and underlying groundwater that are hundreds of miles inland. Shown here: an aerial view of Drakes Bay, par...

Natural History / Natural History - 10 months ago

What is eutrophication?

This NASA Earth Observatory image shows the region where the Mississippi River meets the Gulf of Mexico. It illustrates how sediment is moved from the land to the sea. The Mississippi River carries millions of tons of nutrient-rich sediment into...

Natural History / Natural History - 10 months ago

What is high tide flooding?

As relative sea level increases, it no longer takes a strong storm or a hurricane to cause coastal flooding. Flooding now occurs with high tides in many locations due to climate-related sea level rise, land subsidence, and the loss of natural barrie...

Natural History / Natural History - 1 year ago

How does sand form?

The giant bumphead parrotfish is an amazing fish that can live to be 40 years old, growing up to four feet long and 100 pounds. They use their large head bumps to literally bump heads during competitive displays, when large numbers of fish aggreg...

Natural History / Natural History - 1 year ago

What is a Rossby wave?

Rossby waves naturally occur in rotating fluids. Within the Earth's ocean and atmosphere, these planetary waves play a significant role in shaping weather. This animation from NASA's Goddard Space Flight Center shows both long and short atmosphe...

Natural History / Natural History - 1 year ago

What is a tide gauge?

The rise and fall of the tides play an important role in the natural world and can have a marked effect on maritime-related activities. The image aboves shows the NOAA San Francisco Tide Station, in operation for more than 150 years. A tide ga...

Natural History / Natural History - 1 year ago

What is a King Tide?

A king tide viewed from south of Pier 96 in San Francisco, California, in February, 2016. Credit: Dave Rauenbuehler A King Tide is a non-scientific term people often use to describe exceptionally high tides. Tides are long-period waves that ro...

Natural History / Natural History - 1 year ago

What are the Roaring Forties?

A research vessel braves the strong westerly winds of the Roaring Forties during an expedition to measure levels of dissolved carbon dioxide in the surface of the ocean. During the Age of Sail (circa 15th  to 19th centuries), these strong prev...

Natural History / Natural History - 1 year ago

Are all fish cold-blooded?

Fisheries biologist Nicholas Wegner of NOAA Fisheries' Southwest Fisheries Science Center in La Jolla, California, lead author of the a 2015 research paper that discovered the unique warm-blooded characteristics of the opah (shown here). Not a...

Natural History / Natural History - 1 year ago

What is ocean noise?

Humpback whales swimming underwater. Photo credit: Ed Lyman/NOAA, under NOAA permit #14682 Many marine organisms rely on their ability to hear for their survival. Sound is the most efficient means of communication underwater and is the primary...

Natural History / Natural History - 1 year ago

What are the trade winds?

The Charles W. Morgan is the last of an American whaling fleet that once numbered more than 2,700 vessels. Ships like the Morgan often used routes defined by the trade winds to navigate the oceans. Known to sailors around the world, the trade...