A CTD (conductivity, temperature, and depth) gadget. The first perform of this device is to detect how the conductivity and temperature of the water column modifications relative to depth. Conductivity is a measure of how nicely an answer conducts electrical energy. Conductivity is straight associated to salinity, which is the focus of salt and different inorganic compounds in seawater. Salinity is among the most simple measurements utilized by ocean scientists. When mixed with temperature knowledge, salinity measurements can be utilized to find out seawater density, which is a major driving power for main ocean currents.
In 1865, the Danish geologist and mineralogist Johan Georg Forchhammer, with the assistance of naval and civilian collaborators, collected quite a few samples of seawater from the Northern Atlantic and the Arctic Ocean. He needed to find out why the salinity (or “saltiness”) of seawater varies in numerous areas of the ocean.
Forchhammer put the samples by way of an in depth collection of chemical analyses and located that the proportions of the key salts in seawater keep about the identical all over the place. This fixed ratio is named Forchhammer’s Precept, or the Precept of Fixed Proportions. Along with this precept, Forchhammer is credited with defining the time period salinity to imply the focus of main salts in seawater.
Forchhammer’s discovery helped scientists perceive that salinity ranges in seawater range as a result of addition or elimination of recent water, reasonably than differing quantities of salt minerals within the water. The precept remains to be utilized right now in marine analysis, and supplies a easy option to estimate salinity and hint the blending of water lots within the international ocean.