NOAA logo National Ocean Service

What are the Roaring Forties?

8 February 2017, 4:50 pm

‚ÄčA 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 prevailing winds propelled ships across the Pacific, often at breakneck speed. Nevertheless, sailing west into heavy seas and strong headwinds could take weeks, especially around Cape Horn at the southern tip of South America, making it one of the most treacherous sailing passages in the world. The Roaring Forties take shape as warm air near the equator rises and moves toward the poles. Warm air moving poleward (on both sides of the equator) is the result of nature trying to reduce the temperature difference between the equator and at the poles created by uneven heating from the sun.

Continue reading →

Original article: What are the Roaring Forties?