The effect of mountain uplift on eastern boundary currents and upwelling systems
<p>All major mountain ranges are assumed to have been subject to increased uplifting processes during the late Miocene and Pliocene. Previous work has demonstrated that African uplift is an important element to explain Benguela upper-ocean cooling in the late Miocene–Pliocene. According to pro...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2020-01-01
|
| Series: | Climate of the Past |
| Online Access: | https://www.clim-past.net/16/161/2020/cp-16-161-2020.pdf |
| Summary: | <p>All major mountain ranges are assumed to have been
subject to increased uplifting processes during the late Miocene and
Pliocene. Previous work has demonstrated that African uplift is an important
element to explain Benguela upper-ocean cooling in the late
Miocene–Pliocene. According to proxy records, a surface ocean cooling also
occurred in other eastern boundary upwelling regions during the late
Neogene. Here we investigate a set of sensitivity experiments altering
topography in major mountain regions (Andes, North American Cordillera, and
southern and East African mountains) separately with regard to the potential impact
on the intensity of near-coastal low-level winds, Ekman transport and Ekman
pumping, and upper-ocean cooling. The simulations show that mountain
uplift is important for upper-ocean temperature evolution in the area of
eastern boundary currents. The impact is primarily on the atmospheric
circulation which is then acting on upper-ocean temperatures through changes
in strengths of upwelling, horizontal heat advection and surface heat
fluxes. Different atmosphere–ocean feedbacks additionally alter the sea
surface temperature response to uplift. The relative importance of the
different feedback mechanisms depends on the region, but it is most likely also
influenced by model and model resolution.</p> |
|---|---|
| ISSN: | 1814-9324 1814-9332 |