Shrnutí

Popis

The HOT program makes repeated observations of the physics, biology and chemistry at a site approximately 100 km north of Oahu, Hawaii. Two stations are visited about once a month: Kahe Point (Station 1: 21.34N, 158.27W) and Station ALOHA (Station 2: 22.75N, 158W). Various other stations are made intermittently in support of similar research objectives or mooring deployments. Samples of water column chemical analyses were collected mostly in the upper 1000m using Niskin bottles mounted on a rosette. The strategy was to sample at density horizons within the main thermocline at pressure horizons above and below this region (i.e., 2000 dbar). Care was applied to ensure the highest possible accuracy and precision. Parameters included salinity, oxygen, dissolved inorganic carbon, titration alkalinity, pH, inorganic and organic nutrients, nitrate plus nitrite, dissolved total nitrogen, dissolved phosphate, dissolved silica, dissolved organic carbon, particulate phosphorus, adenosine 5'-triphosphate, pigments, and others. As part of the HOT program two transect cruises (ALOHA-Climax: AC) have been conducted near the HOT area, from Oahu along the TOPEX line to station Climax (~28N, 155 20'W). Water samples have been obtained at station HALE-ALOHA during cruises conducted for retrieval and/or re-deployment of the bottom-moored buoy. These casts are used for calibration of the sensors attached to the mooring.