Characteristic Numbers of Salinity (independent of tides)

Graphical representation (available in -format, 32k) of tide independent characteristic numbers of salinity (with German text only). This graphical representation is also available in Encapsulated PostScript format ( 31k).

Motivation

Calculation and graphic display of several tide-independent characteristic numbers of salinity can yield additional insight into salinity related phenomena of natural coastal and/or inland waters. In contrast to the computation of the tidal characteristic numbers of salinity the tide-independent numbers can be preferable used for

• natural waters which are not dominated by the tides, e.g. like the coastal waters and estuaries along the Baltic Sea coast of Germany, or in
• extreme situations, like for example periods of high or low fresh water runoff, when salinity may deviate strongly from the average (tide-dominated) conditions, as well as for the
• determination of characteristic values of salinity (e.g. HS and LS) for an arbitrary long (or short) period of time.

In particular there are several useful applications possible for this type of data analysis:

• In addition to informations about the highest and lowest salinity values which occur during an arbitrary period one can calculate also the maximum salinity difference for this time span. This is a good indicator for the natural variability of salinity.
• Maximum values for the increase and decrease of salinity are an additional measure for the characterization of e.g. extreme runoff situations.
• From the computed times for the duration of high salinity and the duration of low salinity one can draw conclusions with respect to the impact of salinity on organisms living in the water or along the beaches.
• The variance of the time-dependent salinity evolution with respect to mean salinity can be used as an indicator for the dynamics of a natural water system.

An automatic analysis of all tide-independent characteristic numbers of water level is carried through by the computer program LZKSF.

Definitions for the tide-independent characteristic numbers of salinity

Maximum Value of Salinity (HS)

Highest value of salinity within an arbitrary period of time

Minimum Value of Salinity (LS)

Lowest value of salinity within an arbitrary period of time

Mean Value of Salinity (MS)

Arithmetic mean of salinity for an arbitrary period of time

Maximum Salinity Difference (HS-LS)

Difference in salinity between HS and LS for an arbitrary period of time

Maximum Increase of Salinity

Maximum increase of salinity (during one hour) within an arbitrary period of time

Example: Maximum Increase of Salinity in the Ems Estuary

Maximum Decrease of Salinity

Maximum decrease of salinity (within one hour) within an arbitrary period of time

Example: Maximum Decrease of Salinity in the Ems Estuary

Standard Deviation of Salinity

Standard deviation of salinity with respect to the mean value of salinity within an arbitrary period of time.

Variance of Salinity

Variance of salinity with respect to the mean value of salinity within an arbitrary period of time

Duration of High Salinity

Period of time during which salinity lies above a specific threshold for salinity

Duration of Low Salinity

Period of time during which salinity lies below a specific threshold for salinity

---

back to Analysis of Calculated Results

---

Overview