According to sailing folklore, a sense of excitement and restlessness can sweep over sailors as they began to approach their destination, even though no land is yet in sight. The giddiness that portends a journey’s end is called “Channel Fever”. It is said to be named for the English Channel, because the confined waters in the Channel had noticeably different motion than the open sea – and this changing motion, although subtle at times, would alert sailors that they had returned to home waters and would soon be in port.
An important shipping and sailing lane, the English Channel connects the North Sea to the Atlantic Ocean, and separates southern England (in the west) from northern France, Belgium and the Netherlands. In this image, black lines delineate the boundaries of these three countries on the eastern coast of the Channel, with France in the south and the Netherlands in the north. The Channel is about 350 mi (560 km) long and 150 mi (240 km) long. It averages 207 ft (63 m) in depth, but the deepest spot is 571 feet (174 m). The narrowest part of the Channel forms the Strait of Dover, and marks the boundary between the Atlantic Ocean and the North Sea. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite flew across the English Channel on April 16, 2014 and captured this true-color image.
At the time this image was captured, the waters in the Channel were colored in many shades of tan, green and blue. Near the coastlines, as well as in the River Severn (west side of southern England) the muddy-colored tans indicated sediment in the water, most likely from run-off. As sediment sinks, its reflective properties change, and sediment can appear either greenish or blue. Phytoplankton, small plant-like organisms, can also color waters in various shades of greens and blues, especially if the blue has a milky cast. Much of the coloration in the Channel is clearly sediment, but some may also be phytoplankton.