Temperature and the conductivity of sea water

Question

I came across a table in Griffith Introduction to Electrodynamics (2nd edition, p 297), which shows a table of various resistivities for different materials. I found it surprising that sea water is listed as a semiconductor here.

As it turned out, I could not find much online agreeing or disagreeing with this. Wikipedia introduces semiconductors as the following:

A semiconductor is a material, which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way.

I am not sure about the second property here, and I was wondering if sea water, as an electrolyte solution, actually exhibits this effect.

Answer 1

I asked the Internet, and the Internet came through. Yes, seawater conductivity does rise with temperature (graph from Temperature Effects on Conductivity of Seawater and Physiologic Saline, Mechanism and Significance, Sauerheber and Heinz, Chem Sci J 2015, 6:4).

So seawater meets the Wikipedia definition of a "semiconductor".

However, in the same reference, frozen seawater has a similar conductivity but a negative conductivity vs. temperature slope, presumably kicking it out of Wikipedia's definition of "semiconductor" and leaving it homeless.