Bathymetry is defined as the underwater depth of the floor of water bodies, such as oceans and seas as well as lakes and rivers. In other terms, it is the relief map of underwater land. Bathymetry is relevant to the fields of oceanography, marine geology, marine biology and also climatology. Bathymetry maps allow the analysis…
Sea Surface Temperature (SST) is defined as the temperature of the uppermost mixed layer of the ocean (i.e. the water column close to the surface). SST is of major importance when studying oceans and seas. Indeed, SST pilots a large range of thermal, metabolic and biological processes. Thus, it is an important variable for weather…
surface salinity (SSS) is defined as the salt concentration in seawater. More precisely, it is the number of grams of salt per 1000 grams of water. One gram of salt per 1000 grams of water is defined as the Practical Salinity Unit (PSU) or as the Part Per Thousand (PPT) unit. SSS is a very…
Net Primary Production (NPP) is defined as the net amount of carbon uptake of the ocean through phytoplankton photosynthesis. NPP measures the mass of carbon available for marine ecosystem functioning.
pH is a measure of the ocean acidity. Low pH values indicate an acid environment whereas high pH values show basic environment. Large quantities of CO2 are absorbed by seawater. During this process, chemical reactions occur resulting in a diminishing of pH, and so an increase in acidity. Water pH is important for marine organisms…
This section refers to the concentration of elements such as the oxygen, the carbon, phosphate (etc.) in seawater. Oxygen is a very important variable as it is absolutely essential for the marine organisms. Too high or too low concentrations of oxygen can deadly affect the aquatic life. The oxygen level in the water is piloted…
Chlorophyll is the green pigment of the photosynthesis process. Chlorophyll concentration is the amount of chlorophyll per cube meter of water. It is used as a proxy of the phytoplankton biomass in seawaters. Phytoplankton amount is one of the most important variables. Indeed, phytoplankton is the basis of the whole marine food chain and is…
CDOM, for Coloured Dissolved Organic Matter, is the absorption coefficient of various dissolved organic materials in the water. CDOM is an important variable to understand and monitor biogeochemical processes in marine ecosystems. Indeed, CDOM decreases the amount of light penetrating the water. As a consequence, an increase in CDOM results in a decrease in light…
Total Suspended Matter (TSM) is defined as the concentration of the total suspended matter in water. TSM includes both organic particles (plankton, detritus, etc.) and mineral particles (e.g. clay particles), and is a measure of the water turbidity. As TSM interferes with the passage of light through the water, it leads to water turbidity, changes…
