Mode-1 internal tides in the western North Atlantic Ocean

نویسنده

  • Brian D. Dushaw
چکیده

Mode-1 internal tides were observed the western North Atlantic using an ocean acoustic tomography array deployed in 1991–1992 centered on 251N, 661W. The pentagonal array, 700-km across, acted as an antenna for mode-1 internal-tides. Coherent internal-tide waves with O(1m) displacements were observed traveling in several directions. Although the internal tides of the region were relatively quiescent, they were essentially phase locked over the 200–300 day data record lengths. Both semidiurnal and diurnal internal waves were detected, with wavenumbers consistent with those calculated from hydrographic data. The M2 internal-tide energy flux was estimated to be about 70Wm , suggesting that mode-1 waves radiate 0.2GW of energy, with large uncertainty, from the Caribbean island chain at this frequency. A global tidal model (TPXO 5) suggested that 1–2GW is lost from the M2 barotropic tide over this region, but the precise value was uncertain because the complicated topography makes the calculation problematic. In any case, significant conversion of barotropic to baroclinic tidal energy does not occur in the western North Atlantic basin. It is apparent, however, that mode-1 internal tides have very weak decay and retain their coherence over great distances, so that ocean basins may be filled up with such waves. Observed diurnal amplitudes were an order of magnitude larger than expected. The amplitude and phase variations of the K1 and O1 constituents observed over the tomography array were consistent with the theoretical solutions for standing internal waves near their turning latitude. The energy densities of the resonant diurnal internal waves were roughly twice those of the barotropic tide at those frequencies. r 2006 Elsevier Ltd. All rights reserved.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Contributions of Atlantic Ocean to June-August Rainfall over Uganda and Western Kenya

This study investigates the contributions of Atlantic Ocean to June-August rainfall over Uganda and western Kenya (KU). The study has utilized the datasets including precipitation from the Global Precipitation Climatology Centre, North Atlantic Oscillation Index (NAOI), South Atlantic Ocean Dipole Index (SAODI), ERA-interim reanalysis, and the Atlantic Ocean Sea Surface Temperature (SST). Singu...

متن کامل

North Atlantic Modeling of Low-frequency Variability in Mode Water Formation

The generation of interannual and near-decadal variability in the formation of mode waters in the western North Atlantic is investigated in the realistic framework of an isopycnic coordinate ocean model forced with atmospheric data from 1946 to 1988. At Bermuda, the model reproduces quite well the observed potential vorticity and isopycnal depth anomalies associated with the subtropical mode wa...

متن کامل

Comparison Study of Subtropical Mode Waters in the World Ocean

Subtropical ModeWater (STMW) is a distinctive feature of the upper ocean in the western part of subtropical gyres in the world ocean. This paper proposes a common criterion of STMW to quantify and compare spatial structures of STMWs in different basins. STMW can be defined as a thermostad (a layer weakly stratified in temperature) by applying a criterion of averaged core layer temperature (CLT)...

متن کامل

Hydrography of chromophoric dissolved organic matter in the North Atlantic

The distribution and optical absorption characteristics of chromophoric dissolved organic matter (CDOM) were systematically investigated along three meridional transects in the North Atlantic Ocean and Caribbean Sea conducted as part of the 2003 US CLIVAR/CO2 Repeat Hydrography survey. Hydrographic transects covered in aggregate a latitudinal range of 51 to 621 north along longitudes 201W (line...

متن کامل

Internal tides and baroclinicity in the southern Weddell Sea 1. Model description

Near the continental shelf break in the southern Weddell Sea, Warm Deep Water and Western Shelf Water meet. Mixing mechanisms, such as internal tides, have the potential to mix these water masses and form Antarctic Bottom Water. A modified version of the Princeton Ocean Model was utilized to investigate the internal tidal fields generated by the interaction of the M2 barotropic tide with topogr...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2005