Woods Hole - Hawaii Ocean Time-series Site

The Woods Hole Oceanographic Institution (WHOI)
Hawaii Ocean Timeseries (HOT) Site (WHOTS)

WHOTS is a coordinated part of HOT, and consists of a mooring that has been providing measurements of high-quality air-sea fluxes and the associated upper ocean response at Station ALOHA, about 100 km north of Oahu, Hawaii since August 2004. WHOTS is funded by NOAA and NSF and it is led by the WHOI Upper Ocean Processes Group. MORE



The WHOTS mooring is located at station ALOHA (a 6 nautical mile radius circle centered at 22 45'N, 158 W) in the central subtropical gyre of the North Pacific. The mooring has been in place for one-year periods since 2004 at a location that has been alternating between the eastern and southern edges of ALOHA (22 46.00'N, 157 53.90'W (Station 50), and 22 40.21'N, 157 57.00'W (Station 52) respectively)


The mooring consists of a surface buoy with meteorological instruments, and a mooring line with subsurface instrumentation anchored to a bottom weight nearly 5,000 m deep.


The buoy has an approximate swing radius of 2.2 nautical miles around the anchor position. The figure on the right shows the current location of the buoy and the swing radius relative to it's anchor position and to Station ALOHA. Also shown are locations of the UW/APL profiling mooring and the ALOHA Cable Observatory node.


The surface buoy is equipped with meteorological instrumentation measuring air and sea surface temperatures, relative humidity, barometric pressure, wind speed and direction, incoming shortwave and longwave radiation, and precipitation. Complete surface meteorological measurements are recorded every minute, as required to compute air-sea fluxes of heat, freshwater and momentum. The system also transmits hourly averages of the surface meteorological variables via the Argos satellite system.

images of sensors


The mooring line is instrumented in order to collect time series of upper ocean temperatures, velocities, and salinities coincident with the surface forcing record.

This includes :

  • Vector measuring current meters (VMCM)
  • Conductivity, pressure and temperature recorders(Microcats)
  • Acoustic Doppler current profilers (ADCP)


images of sensors


This figure is a summary of the data returns from the underwater instruments during the WHOTS 1 through 14 deployments. The red bars correspond to data from the SeaCATs, black bars to ADCP data, and blue bars to VMCM data.