Coupled ocean‐atmosphere nested modeling of the Adriatic Sea during winter and spring 2001

Abstract

Realistic simulations of the Adriatic Sea for over 125 days are conducted using the Navy Coastal Ocean Model with atmospheric forcing provided by the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS is a registered trademark of the Naval Research Laboratory (COAMPS™)). In two separate simulations of the Adriatic, a nested 2‐km‐resolution ocean model is forced by the inner (4‐km) and outer (36‐km) nests of the atmospheric model. Two meteorological stations and two acoustic Doppler current profiler observation sites are used to evaluate modeled atmosphere and ocean velocity fields for 28 January–4 June 2001. Modeled/observed correlations of atmospheric 10‐m velocity are greater than 0.85 for both resolution models. Oceanic 5‐ and 25‐m current fluctuations from both simulations generally match the magnitude and orientation of the observations. The 4‐km‐resolution atmospheric model is differentiated from the 36‐km‐resolution model by its ability to resolve the small‐scale flow structures of the “bora” wind and by its better agreement with observed wind velocity statistics. The ocean simulation forced by the 4‐km‐resolution model is distinguished from the one forced by the 36‐km‐resolution model by its ability to reproduce the expected double‐gyre circulation in the northern Adriatic and by its ability to better capture the magnitude and shape of the observed depth‐dependent velocity correlation with wind at the deeper site. Though the 36‐km forced ocean model agrees better with many observed velocity statistics, the 4‐km forced ocean model produces the highest correlations with observations (exceeding 0.78) at subsurface depths that are most strongly correlated with winds.

ADCP observations of the western Adriatic slope current during winter of 2001

“…6). Maximum cross-covariance magnitudes occur in a pattern very similar to bora wind magnitude patterns (Pullen et al, 2003) with high values along the northern Adriatic coast, off Kvarner Bay, and off Ilovik Island (14.5°N, 44.4°E). Peak cross-covariance occurs at the tip of the Istrian Peninsula just outside Kvarner Bay.…”

SURFEX v8.0 interface with OASIS3-MCT to couple atmosphere with hydrology, ocean, waves and sea-ice models, from coastal to global scales

“…The first ocean-atmosphere high-resolution coupled systems appeared at the beginning of the 2000s to study these interactions (e.g. Pullen et al, 2003;Ren et al, 2004;Loglisci et al, 2004). Nowadays, the development of highresolution, short-to medium-range coupled prediction systems is still challenging, but several groups have undertaken it, based on coupling methods with different levels of sophistication and targeting a large range of applications depending on their interests (Brassington et al, 2015;Heinzeller et al, 2016;Hewitt et al, 2016;Janssen et al, 2013).…”

“…COAMPS also includes nesting capability in the two components and a coupled data assimilation scheme. This system was used in particular over the Adriatic Sea and the Ligurian Sea to evaluate the air-sea interactions during strong wind events, bora and mistral, with resolutions of up to 4 km in the atmosphere and 2 km in the ocean (Pullen et al, 2006(Pullen et al, , 2007Small et al, 2011Small et al, , 2012. A configuration of COAMPS, named COAMPS-TC, was also specifically designed to improve tropical cyclone forecasts (Doyle et al, 2014).…”

Observations of Bora Events over the Adriatic Sea and Black Sea by Spaceborne Synthetic Aperture Radar

“…Bora events also have an effect of the water circulation, which has been studied extensively for the Adriatic Sea, both theoretically and experimentally (see, e.g., Orlic et al 1994;Bergamasco and Gasic 1996;Pullen et al 2003;Loglisci et al 2004;Lee et al 2005;CushmanRoisin and Korotenko 2007). A recent collection of papers dealing with this topic can be found in the special Adriatic Sea issue of J. Geophys.…”