Potamichor, and more.

Moment to sense on the river Clun (2023), photo by me.

In honour of the work of Joy Bear and Richard Thomas, who coined the word petrichor in 1964 to describe the aroma earth emits when rain falls*, I offer potamichor.

ποτάμι Potámi ~ greek ~ river.

Ichor ~ The sacred blood of the Greek Gods.

Potamichor ~ a familiar odour of rivers.

Dimethyl sulfide**, along with other elements and biochemicals, offer the familar and pungent sulphurous odour of sea spray, an important moment of the sulphur/sulfur cycle that aids protein, vitamin and hormone building – I’ll call the smell thalassicor (sea/blood of the gods).

And in the same vein, estuaries and saltmarshes create ekvolichor (estuary/blood of the gods); lakes give off limnichor; ponds – limnoulichor: swamps and bog – telmichor.

Potamichor is complex, with varying cocktails of minerals, biochemicals and olifactory matter bound to be unique to the continuums of river-place given geological, meteorological, climatic, symbiological, microbial (including respiration), ecological and anthropological (extrinsic/intrinsic impacts).

With complexity in matter and directionality, and in a constant state of flux, salmonids, lampreys, twait shad and sturgeon know more than we ever could about potamichor. They smell their particular birth-streams miles out to sea, and without the use of material and energy-greedy tools. Perhaps migratory birds use these cues to navigate too, high up in the atmosphere. And more? Imagine.


  • * Bear, I., Thomas, R. Nature of Argillaceous Odour. Nature 201, 993–995 (1964). https://doi.org/10.1038/201993a0 – geosmins produced by Streptomyces, etc.
  • ** Shemi, A., Alcolombri, U., Schatz, D. et al. Dimethyl sulfide mediates microbial predator–prey interactions between zooplankton and algae in the ocean. Nat Microbiol 6, 1357–1366 (2021). https://doi.org/10.1038/s41564-021-00971-3