The global merchant fleet is huge, with more than 50,000 ships currently in active service, transporting around 90% of the world’s goods.
To get a sense of just how vast and how busy the global marine shipping industry is, take a look at Shipmap.
Global shipping routes (Shipmap.org)
Seen on this scale, it’s not so surprising to learn that the global fuel consumption associated with marine cargo transport is massive. Infact, it accounts for a significant share of the 3.9 million barrels of fuel per day used by all marine vessels.
Sea Pollutants
According to the International Maritime Organisation merchant ships account for approximately 2.5% of global CO2 emissions.
So, the last thing you’d want is something increasing the drag on these already laden ships, slowing them down and increasing fuel consumption just to get from port A to port B. Yet this is precisely what marine biofouling does.
Marine biofouling
Marine biofouling is the buildup of marine organisms on a submerged surface, and it’s a very big problem.
We tend to think of marine biofouling as a long time-scale problem, something that takes place on the scale of months to years.
Small but big
Yet the biofouling process actually begins the instant the ship’s hull touches the water.
This is because organic molecules in the water such as proteins and sugars will adhere to the surface and are held by very weak interactions. Van der Waals forces, which involve the faint attraction between atoms, when they are in close quarters makes a considerable impact.
These may be the weakest possible chemical interactions between molecules, a far cry less potent than the strong covalent forces within a molecule, yet without Van der Waals forces, life itself wouldn’t exist because what these gentle forces lack in individual strength, they make up in sheer numbers. Working together, they help hold proteins in the right shape, and contribute to the stacking of nucleic acid base pairs in a DNA helix.
Along the hull of a ship, these weak interactions enable the formation of a fantastically thin biomolecular coating. This is where the whole problem of biofouling begins, because from there, life can take hold.
How it affects fuel consumption?
The fuel consumption is expected to increase by as much as 6% for every 100 micrometer increase in hull roughness (Source: Shipping and the Environment, 2016).
Ship hulls are designed to glide through water in as streamlined a way as possible, but the gathering of algae, barnacles, mollusks and other marine life can undermine even the most inspired example of sleek naval architecture and can increase fuel consumption up to 40%.
Threat to Aqua life
Marine vessels inadvertently contribute to the global spread of invasive marine species. Scientifically, its a challenge to track the thousands of stowaway species embarking on free rides around the world, but efforts such as DNA barcoding approach at port biosecurity might help keep control.
The problem is, by the time the ships reach port, the invasive species are hard to contain, which is why many efforts — including those reaching back to the 1700’s when the British Navy began using copper hulls — are trying to prevent these stowaway microenvironments from forming in the first place.
But that is another very interesting story altogether!
Did you subscribe for our daily newsletter?
It’s Free! Click here to Subscribe!
Source: Forbes
