Broadening Ocean Current Could Carry Less Heat Poleward With Climate Change
(Click to enlarge) This still image from an animation of ocean surface currents (from June 2005 to December 2007 from NASA satellites) shows how coastal currents like the Agulhas in the Southern Hemisphere move equatorial waters toward Earth’s poles. A new study shows the Agulhas has broadened and grown more chaotic. (Credit: NASA/SVS)
Some ocean currents, like the Agulhas Current in the southwestern Indian Ocean, act like giant air conditioners, moderating Earth’s climate by shuttling heat from the equator toward the poles.
(From Earth / By Adityarup Chakravorty)– The Agulhas is one of the largest and fastest currents in the world: Flowing southwest along the east coast of Africa, it stretches almost 1,500 kilometers and transports about 70 million cubic meters of water every second toward the South Pole at peak speeds upward of 7 kilometers per hour.
Sea-surface temperatures near several currents like the Agulhas, called western boundary currents, have increased more rapidly over the last century compared to temperatures elsewhere in the ocean. This rise in temperature — along with increasing velocities of wind systems across the world — has led researchers to suspect that western boundary currents are gaining strength and transporting more heat poleward. Read the full story »