Mitigation and Conclusion

This blog has pushed against the prevailing wisdom and environmental rhetoric of man-made sea level rise threatening all low lying coral island nations via submergence. Through study of the scientific literature it has shown that only a small number of coral islands may face an uncertain future, in part because of eustatic sea level rise however most of the ‘blame’ for this uncertain future is related to their tectonic and latitudinal context.


In the case of the small number of islands that are shrinking in land area is there anything to be done to prevent submergence or should the leadership decision of the President of the Maldives to buy up land in India, Sri Lanka and Australia for his citizens to relocate to be followed?


Whilst a legally binding and effective control on carbon dioxide emissions over the next century would reduce the extent of warming and therefore reduce the thermal expansion of water and land ice melting, possibly to a scenario such as (B1, shown in an earlier post), sea level rise would still occur due to momentum in the atmosphere causing up to a 38cm rise in sea level by 2099. However it is not the opinion of this author that there will be any such concerted effort to reduce carbon emissions in the near-medium future.


One novel method to increase calcification rates (and therefore accretion rates of coral reefs) was mentioned in yesterday’s post, that of ‘Biorock’, whereby a metal mesh dome is sunk and a low voltage current is fed through it from a solar or wind source, this after one year is covered by coral. The coral has been able to developed rapidly due to the electric current which has inhibited the corals usual competitors. This provides a feeding ground for reef eating fish (such as parrot fish) which then excrete sand, causing reef, and coral island accretion. This is one method of creating an ‘artificial reef’, other less technical reef building methods involve the use of a growing platform such as the popular 'reef ball' program. This non-profit organisation uses the following growing platforms:

 

These platforms provide a large surface area for growth, and are ideal for fisheries as they provide a safe haven from predation. Over 550,000 of these reef balls have been deployed worldwide, providing a home for coral and encouraging biodiversity.

The effectiveness of these programs for encouraging reef accretion rates is yet to be seen, however in theory they should work and are a relatively inexpensive way for often poor coral island nations to combat submergence.

What this blog would like to see is a Webb and Kench style investigation of land area over as long a time period as possible of every low lying coral island worldwide, coupled with an assessment of their latitudinal and tectonic situation resulting in a categorical list of endangered and safe nations. From this an effective strategy could be drawn up by worldwide institutions such as the UN to combat submergence and in rare occasions relocation the populations of islands which are tectonically submerging too rapidly. Through this intimate knowledge of the situation there will be no environmental rhetoric or questionable compensation claims to be railed against by the likes of this blog. And once again science will lead policy as it always should.