View Data
	To assist in the interpretation of the data, it can be displayed using the Hawaii Ocean Time-series Data Organization & Graphical System (HOT-DOGS©).

The majority of our sampling effort, approximately 60-72 h per standard HOT cruise, is spent at Station ALOHA. High vertical resolution environmental data are collected with a Sea- Bird CTD having external temperature (T), conductivity (C), dissolved oxygen (DO) and fluorescence (F) sensors and an internal pressure (P) sensor. A Sea-Bird 24-place carousel and an aluminum rosette that is capable of supporting 24 12-L PVC bottles are used to obtain water samples from desired depths. The CTD and rosette are deployed on a 3-conductor cable allowing for real-time display of data and for tripping the bottles at specific depths of interest. The CTD system takes 24 samples s^-1 and the raw data are stored both on the computer and, for redundancy, on VHS-format video tapes.

Continuous measurements of temperature, salinity, oxygen and fluorescence are made with a Sea-Bird SBE-9/11Plus CTD package with dual temperature, salinity and oxygen sensors and fluorometer described in Tupas et al. (1995). CTD underwater unit #09P43777-0850 (referred to as #0850) was used during all cruises except HOT-200 and 201, during which unit #91361 was used.

CTD casts were made at Stations Kahe and ALOHA during each 2008 cruise, except during HOT-207. No CTD casts were done during HOT-207; this cruise was cancelled due to problems with the CTD winch and is not included in this report. Data reported for "all cruises" in 2008 refers to HOT-199 through HOT-206. A CTD cast to 1000 m was made at Station Kahe during all cruises.

At Station ALOHA, a burst of consecutive CTD casts to 1000 m is made over 36 hours to span the local inertial period and three semi-diurnal tidal cycles. One WOCE standard cast within 10 m of the bottom is made during each cruise. A second deep cast was obtained at this Station during every 2008 cruise.

A CTD cast to 2400 m was conducted at Station Kaena during every 2008 cruise except HOT-203 and 206.

CTD casts have been conducted during cruises near the WHOTS mooring since August 2004, for calibration of the moorings' sensors. CTD yo-yo casts to 200-m of at least five cycles were conducted during the 2008 cruises. Station 52 (22 40.21'N, 157 57'W) was occupied during HOT-199 through 201. After cruise 201, the WHOTS mooring was recovered and re-deployed to near the eastern edge of the ALOHA circle (Station 50: 22 46'N, 157 53.83'W). Station 50 was occupied during HOT-202 through 206 cruises. Two consecutive casts were conducted near the mooring during cruises 199, 202, and 206.

CTD data were acquired at a rate of 24 samples per second. Digital data were stored on a laptop personal computer and, for redundancy, the CTD signal was recorded on VHS videotapes. Backups of CTD data were made onto Zip disks and later onto compact disks. The raw CTD data were quality controlled and screened for spikes as described in Winn et al. (1993). Data alignment, averaging, correction and reporting were done as described in Tupas et al. (1993). Salinity spike rejection parameters were modified for some cruises in 2008 because of rough sea conditions. Spikes occur when the CTD samples the disturbed water of its wake; therefore, samples from the downcast are rejected when the CTD is moving upward or when its acceleration exceeds 0.5 m s^-2 in magnitude. Cruises 199 and 200 were conducted under relatively rough conditions. The CTD acceleration cutoff value had to be increased to between 0.55 and 0.65 m s^-2 for some of the casts to relax the data rejection criteria and avoid eliminating an excessive number of points.

The data were additionally screened by comparing the temperature and conductivity sensor pairs. These differences permitted identification of problems in the sensors. Only the data from one set of T-C sensors and one oxygen sensor, whichever was deemed most reliable, is reported here.

Temperature is reported in the ITS-90 scale. Salinity and all derived units were calculated using the UNESCO (1981) routines; salinity is reported in the practical salinity scale (PSS-78). Oxygen is reported in µmol kg^-1. Chloropigment (Fluorescence) in µg/l.