seawater properties II

what are the major ions in seawater

chloride, sodium, magnesium, potassium, sulfate, calcium

what does sodium do to seawater

makes it denser

what is the equation for residence times

reservoir size / rate of removal

what is the difference in slow and short rates of removal in regard to residence time

slow removal - long residence times

fast removal - short residence times

what is the principle of constant proportions

major elements in seawater exist in constant proportion to each other

why is the principle of constant proportions important in oceanography

provides the basis for salinity determinations

why are the residence times of major ions in seawater much longer than in open oceans

oceans are in a steady state, and major ions are well mixed

what is meant by major ions showing conservative behaviour

concentration changes are only due to addition or removal of freshwater, evaporation, precipitation river discharge or ice melt and formation

what are exceptions to the conservative behaviour of seawater

landlocked seas, low oxygen waters, ice formation, carbonate formation, seawater-magma reactions

the defintion of salinity

the total amount of all the major ions in a sample of seawater defined by its mass

what are the units used to measure salinity

salinity is a unitless fraction

how is salinity reported

as a mass ratio of grams of major ions per 1kg of seawater

what is used in modern methods of measuring salinity

use conductivity methods by passing a current through the seawater sample proportional to its salinity

what processes affect salinity

evaporation, precipitation, river discharge, ice melt, ice formation

how does ice formation affect salinity

major ions are not incorporated into ice and the rejected salts form highly saline brines, increasing sea surface salinity

what is the key part of the carbonate system

dissolved inorganic carbon

what is the 7th most abundant major ion that is also involved in the carbonate system

carbonate

what does the distribution of DIC reflect

seawater pH

what is expected to drop due to anthropogenic CO2 in the atmosphere

natural sequestration of CO2

what does TA stand for

total alkalinity

how does TA affect pH

it buffers pH change because hydrogen ions interract with basic ions