Sensitivity of the tropical Atlantic to vertical mixing in two ocean models (ICON-O v2.6.6 and FESOM v2.5)

• DOI: 10.5194/egusphere-2024-2281
• Publication Date: 2024-07-24T09:48:28Z
• Authors: Swantje Bastin; Aleksei Koldunov; Florian Schütte; Oliver Gutjahr; Marta Agnieszka M...; Tim Fischer; Radomyra Shevchenko; Arjun Kumar; Nikolay Koldunov; Helmuth Haak; Nils Brüggemann; Rebecca Hummels; Mia Sophie Specht; Johann Jungclaus; Sergey Danilov; Marcus Dengler; Markus Jochum
• Keywords: Mixed layer; Langmuir Turbulence; Ocean dynamics

Abstract. Ocean General Circulation Models still have large upper-ocean biases e.g. in tropical sea surface temperature, possibly connected to the representation of vertical mixing. In earlier studies, ocean mixing parameterisation has usually been tuned for a specific site or only within model. We present here systematic comparison effects changes scheme two different global models, ICON-O and FESOM, run at horizontal resolution 10 km Atlantic. test commonly used schemes; K-Profile Parameterisation (KPP) Turbulent Kinetic Energy (TKE) scheme. Additionally, we vary tuning parameters both schemes, addition Langmuir turbulence TKE show that mean subsurface currents mixed layer depth differ more between models than runs with settings each For ICON-O, there is larger difference KPP FESOM. varying hardly affects pattern magnitude state biases. smaller scale variability like diurnal cycle inertial waves, choice can matter: diurnally enhanced penetration equatorial below simulated TKE, not KPP. However, schemes does lead improvements these processes. conclude substantial part upper Atlantic sensitive details