Comparative and Analytical Study of the Sea Currents Data from High-Frequency Radar and Acoustic Doppler Current Profiler in The Bali Strait (Case Study: April 24th - May 3rd, 2019) Yoshua Ade Nugroho(a*), Imma Redha Nugraheni(b), Muhammad Najib Habibie(c), Hastuadi Harsa(c), Roni Kurniawan(c), and Tahir Daniel Hutapea(c)
(a)Frans Kaisiepo Meteorological Station
Jl. M. Yamin, Biak Kota, Biak Numfor, Papua, 98111, Indonesia
*yoshua.meteo[at]gmail.com
(b)Department of Meteorology, School of Meteorology Climatology and Geophysics
Jl. Perhubungan I No. 5, Pondok Aren, Tangerang Selatan, Banten, 15221, Indonesia
(c)Research and Development Center, Meteorological Climatological and Geophysical Agency
Jl. Angkasa I No. 2, Kemayoran, Jakarta Pusat, DKI Jakarta, 10610, Indonesia
Abstract
A High Frequency Radar (HF Radar) operating at 4.4 - 50 MHz was used as part of the The Bali Strait Wave and Current Survey Project by Indonesian Meteorological Climatological and Geophysical Agency (BMKG) Research and Development Center on April 24th - May 3rd 2019. The radar system observed the sea surface currents of the northern part of Bali Strait from two sites separated by about 6 km. Measurements were taken every half an hour for each location on a 0.5 x 0.5 km grid. In order to examine the performance of HF Radar, observed data from HF Radar were compared to sea surface currents measured by two Acoustic Doppler Current Profiler (ADCP) deployed 20 m below the sea surface. Additional information was also conducted from the ADCP to determine the characteristics of the radial velocity and direction of sea currents for each layer. The radar and ADCP currents radial velocity were in the same range of distribution with the radar tended to overestimate the ADCP, and only well-correlated in the first high tide and second low tide period. There was a distortion in the directional measurement of the radar because of the influence from the surface winds right above the sea level. In addition, the characteristics of the ocean currents radial velocity in the Bali Strait showed good persistence in the lower layer rather than the upper layer to the surface.
