Marine chemistry
Marine chemistry studies the composition of seawater and the chemical processes that occur in oceans and other marine environments.
Carbonate system: The linked forms of dissolved carbon dioxide, bicarbonate, and carbonate that govern seawater pH and buffering. Its equilibria control ocean acidity and the availability of carbonate for shells.
Seawater: The saline water that fills seas and oceans, containing dissolved ions, gases, and organic matter. Its composition is the central subject marine chemistry describes.
Ocean observation: The systematic measurement of physical, chemical, and biological properties of the ocean. Chemical sampling and sensors provide evidence about ocean conditions and change.
Ocean deoxygenation: The decline of dissolved oxygen in ocean waters over time. Its causes and regional patterns remain important questions for chemical observation and modeling.
Ocean acidification: The decline in ocean pH caused mainly by seawater absorbing atmospheric carbon dioxide. It shows how atmospheric exchange changes seawater chemistry and affects marine life.
Salinity: A measure of the concentration of dissolved salts in water. Salinity helps characterize seawater and affects density, circulation, and chemical equilibria.
Ocean carbon cycle: The movement and storage of carbon among the ocean, atmosphere, organisms, and sediments. Marine chemistry quantifies how much carbon the ocean absorbs, transforms, and stores.
Ocean alkalinity enhancement: Proposed approaches to increase seawater alkalinity to promote carbon dioxide uptake and storage. Its effectiveness, ecological effects, and permanence depend on marine chemical processes.
Biological pump: The movement of carbon from surface waters into the ocean interior through biological production and sinking particles. It redistributes carbon and nutrients between surface waters and the deep ocean.
Dissolved oxygen: Molecular oxygen present in water, available to aquatic organisms and chemical reactions. Its concentration tracks biological production, respiration, and ventilation of ocean waters.