eLXg {bNX: Sampling Information of the JKEO1


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The JKEO1 sampling is based on the KEO of which prototype is TAO moorings in the tropical Pacific.

The following description is based on that in KEO web site.

All data collected from the JKEO1 mooring are publicly available. Daily averaged surface and subsurface data from the JKEO1 mooring are made available in near real-time. In addition, spot values of high resolution surface meteorological data transmitted opportunistically are also made available in near real-time. Higher resolution data are recorded onboard the mooring and will be made available in this web site.

The table below describes the sampling schemes for the JKEO1 moorings. Observation times in data files are assigned to the center of the averaging interval unless otherwise noted. For example, daily averages are computed starting at 0000 UTC and are assigned an observation "time stamp" of 1200 UTC.

JKEO1 measures winds, air temperature, relative humidity, sea surface temperature and salinity (SST and SSS), and subsurface temperatures and salinity as well as rainfall, and shortwave and long wave radiation. Data from JKEO1 had been available on the GTS network since May 22, 2007.

Last Updated on December 26, 2008

Measurement

Sample rate

Sample period

Sample time

Data recorded in memory

Transmitted data

Wind velocity components, air temperature, relative humidity

2-Hz

2 min

2359-0001, 0009-0011,...

10 min

Daily mean and 2-min mean from top of most recent hour

Rain rate [1]

1-Hz

1 min

0000-0001, 0001-0002,...

1 min

Daily mean, standard deviation, and percent time raining

Shortwave radiation

1-Hz

2 min

2359-0001, 0001-0003,...

2 min

Daily mean and standard deviation

Longwave radiation (thermopile, case and dome temperatures)

1- Hz

2 min

2359-0001, 0001-0003,...

2 min

Daily mean

Sea surface and subsurface temperature and conductivity [2]

1 per 10 min

instantaneous

0000, 0010,...

10 min

Daily mean

[1] To reduce instrumental noise, internally recorded 1-minute rain accumulation values are smoothed with a 16-minute Hanning filter upon recovery. These smoothed data are then differenced at 10-minute intervals and converted to rain rates in mm hr-1. The resultant rain rate values are centered at times coincident with other 10-minute data (0000, 0010, 0020...). For further information see Serra et al (2001).

[2] To minimize spiking in the salinity record due to sensor response time mismatches, the internally recorded 10-minute conductivity and temperature values are smoothed with a 13-point Hanning filter and subsampled at hourly intervals. Salinities are calculated from the smoothed hourly conductivity and temperature values using the method of Fofonoff and Millard (1983). These hourly data constitute the high-resolution salinity time series in the data base. High-resolution temperatures are offered at their original 10-minute sampling increment.

References:
Fofonoff, P., and R. C. Millard Jr.: Algorithms for computation of fundamental properties of seawater, Tech. Pap. Mar. Sci., 44, 53 pp., Unesco, Paris, 1983.

Freitag, H.P., M.J. McPhaden, C.S. Coho, and A.J. Shepherd (1991): Equatorial wind, current and temperature data: 108W to 140W; April 1983 to October 1987. NOAA Data Report ERL PMEL-35 (PB92-119817), 116 pp.

Kutsuwada, K. and H. Inaba, (1995): "Long-Range Measurement of Surface Oceanic Current in the Western Equatorial Pacific by Acoustic Doppler Current Profiler", J. of Meteor. Soc. of Japan, 73, No. 1, pp. 1-11, 1995.

Mangum, L.J., H.P. Freitag, and M.J. McPhaden (1995): TOGA TAO array sampling schemes and sensor evaluations. Proceedings, Oceans '94 OSATES, 13-16 September 1994, Parc de Penfeld, Brest, France, II-402-II-406.

Plimpton, P.E., H.P. Freitag, and M.J. McPhaden (2000): Correcting moored ADCP data for fish-bias errors at 0, 110W and 0, 140W from 1993 to 1995. NOAA Tech. Memo. OAR PMEL-117, 35 pp.

Plimpton, P.E., H.P Freitag, M.J McPhaden, and R.H. Weisberg, (1997): "Using echo intensity to correct moored ADCP data for fish-bias error at 0, 170W", NOAA Technical Memorandum ERL PMEL-111, 17pp.

Serra, Y.L., P.A'Hearn, H.P. Freitag, and M.J. McPhaden, 2001: ATLAS self-siphoning rain gauge error estimates. J. Atmos. Ocean. Tech., 18, 1989-2002.

Weisberg, R.H. and S.P. Hayes (1995): "Upper ocean variability on the equator in the west-central Pacific at 170W", J. Geophys. Res., 100, pp. 20485-20498.

 


Home/Overview | Technical Info | Data


Kuroshio Transport and Surface Flux Group,

Ocean General Circulation Observational Research Program,

Institute of Observational Research for Global Change (IORGC),

Japan Agency for Marine-Earth Science and Technology (JAMSTEC)

2-15 Natsushima-cho Yokosuka-city,Kanagawa, 237-0061, Japan

JKEO web master
OGCORP
IORGC
JAMSTEC