nviera174
14.05.2021 3:08:24
"But we were misled, twice over. Firstly because that distinctive smell is not ozone, it is dimethyl sulphide. And secondly, because inhaling it is not necessarily good for you." more
See full version: What does the sea sell like
"But we were misled, twice over. Firstly because that distinctive smell is not ozone, it is dimethyl sulphide. And secondly, because inhaling it is not necessarily good for you." more
Scientists have known about DMS for many years but the genes responsible for its production have never before been identified. The new findings will be published in the journal Science on Friday February 2. here
"By isolating a single gene from a bacterium collected from the mud of Stiffkey marshes, we deduced that the mechanisms involved in DMS production differ markedly from those that had been predicted," said Prof Johnston. "And we discovered that other, wholly unexpected bacteria could also make that seaside smell." here
"On bracing childhood visits to the seaside we were always told to 'breathe in that ozone, it's good for you'," said Prof Johnston. more
Seaweed is one of the more obvious sources of malodorous compounds. It’s commonly seen washed up on the fringes of the sea, and as it decomposes, it can produce gases that contribute to the ‘sea smell’. The principle gas produced is hydrogen sulfide, which is generated via the bacterial breakdown of organic compounds in the seaweed. Hydrogen sulfide has an odour commonly described as akin to rotting eggs, and is actually a toxic gas in high concentrations.
DMS also has another role in our atmosphere. Although only around 10% of the compound produced in the ocean is released into the air, when it is, it can be broken down, undergoing chemical reactions which lead to the formation of aerosols. Aerosols are tiny particles of solids or liquids suspended in a gas. In the atmosphere, water vapour can condense around these particles – and this leads to cloud formation. Again, DMS and its derivatives are not the only culprits here, with dust, soot, and other small compounds also taking part in the genesis of clouds.
The summer holidays are here, which means there’ll soon be crowds flocking to the coast to spend the day at the beach. The supposed benefits of ‘fresh sea air’ are commonly extolled, but its origins might not be what you think: it’s the chemical compounds produced by algae and seaweed that contribute towards its characteristic smell.
I'm not sure if this works with the smell so much but it's quite common to hear people refer to "Bracing sea air".
Sea air is generally referred to smelling "briny" - which relates to the saltiness of it.
The good smell that you experience once you get out of the car at a beach in wintertime. Would "the chilly smell of the sea" work? Or fresh / odor / some other words?
Asked by: Aline Smith, London here
Saltwater by itself doesn’t have any smell, but the things that live in it certainly do. The rather stale, sulphury smell is dimethyl sulphide, produced by bacteria as they digest dead phytoplankton. At low tide, you’ll also smell chemicals called dictyopterenes, which are sex pheromones produced by seaweed eggs to attract the sperm. And on top of all this is the ‘iodine’ smell of the sea, which is actually the bromophenols produced by marine worms and algae. here
Give a lengthy sniff next time you visit the seaside, you will be taking in a variety of scents produced from within the ocean.
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