HKU Earth Scientists Discovered Century-scale Deep-water Circulation Dynamics in the North Atlantic Ocean throughout the last 20,000 years

Typography

Dr Moriaki Yasuhara, Dr Hisayo Okahashi, and Dr Huai-Hsuan May Huang from School of Biological Sciences and Swire Institute of Marine Science of the University of Hong Kong (HKU), in collaboration with scientists in Lamont-Doherty Earth Observatory of Columbia University, Duke University, and US Geological Survey have recently reported their discovery on a key driver of past and perhaps future abrupt climate change that is deep-water dynamics in the North Atlantic Ocean in the journal Geology.

Dr Moriaki Yasuhara, Dr Hisayo Okahashi, and Dr Huai-Hsuan May Huang from School of Biological Sciences and Swire Institute of Marine Science of the University of Hong Kong (HKU), in collaboration with scientists in Lamont-Doherty Earth Observatory of Columbia University, Duke University, and US Geological Survey have recently reported their discovery on a key driver of past and perhaps future abrupt climate change that is deep-water dynamics in the North Atlantic Ocean in the journal Geology.

Since the proposal of “conveyor belt” paradigm by Wallace S Broecker, in 1980s, the deep ocean circulation, now known as the Atlantic Meridional Overturning Circulation (AMOC), has been widely regarded as an important driver of global climate changes. The AMOC is a process that cold and salty surface water sinks into deep ocean in the high-latitude North Atlantic Ocean, the lower limb deep water (known as North Atlantic Deep Water: NADW) flows southward (Image 1), and eventually upwells to the surface in the North Pacific Ocean. The strength of this circulation is known to affect global heat flow and regional climates. To study this circulation dynamics, the North Atlantic Ocean is especially important, because it is the place that deep water is formed through cooling surface water in the high latitude.

Read more at The University of Hong Kong

Image: Atlantic meridional overturning circulation.  CREDIT: NASA / Goddard Space Flight Center Scientific Visualization Studio (http://svs.gsfc.nasa.gov/3884)