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Surface Coastal regions periodically experience upwelling events where deeper ocean water circulates onto continental shelves and near-shore areas.
This exposes the productive upper ocean ecosystems to colder water containing more nutrients & more CO2.
As ocean acidification makes the upper oversaturated layer of sea water shallower each year, these natural upwelling events will more often cause undersaturated water to well up and flow to the shore.
Coastal marine organisms that form shells are unaccustomed to such events, and periodic exposures to these significantly different conditions may affect these communities.
However, rock weathering takes tens of thousands of years so will not remove the current anthropogenic input of CO2 to the atmosphere and ocean fast enough.
On shorter time scales (>1,000 years), the ocean has an internal stabilizing feedback linking the ocean carbon cycle to the underlying carbonate rich sediment known as carbonate compensation.
The upper layers of the ocean tend to be supersaturated with CaCO3 so little dissolution takes place, whilst the deep ocean is undersaturated and carbonate readily dissolves.
The first boundary between these two states is known as the lysocline, the depth at which dissolution strongly increases in the deep ocean.
The CaCO3 in the form of dead shells sink to the sea bed. If it is of shallow water depth, the majority is buried in the sediment and trapped for a long time, but where the shells sink in deep water nearly all the CaCO3 is dissolved, thereby not locking the carbon away for millions of years.
The current increased rate of dissolution of atmospheric CO2 into the ocean results in an imbalance in the carbonate compensation depth (CCD), the depth at which all carbonate is dissolved.
As the pH of the ocean falls, it results in a shallowing of the lysocline and the CCD, thus exposing more of the shells trapped in the sediments to understaturated conditions causing them to dissolve, which will help buffer ocean acidification but over a long time scale of a thousand years.
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The park had been put on the tentative list of future heritage sites of UNESCO in 2009 and had been included in the final list in 2014. The Odisha government had submitted a dossier, compiled by the Wildlife Institute of India, recommended to UNESCO that the park be declared a World Heritage Site.