My previous blog talks about the Black Swan effect and why it is better to be an “alarmist” when it comes to climate change. This blog discusses an event that justifies the need to be alarmist when it comes to climate change. The event is the earthquake in the Oceania region that adversely affected the island nation of Samoa and the American Samoa.
About the Samoan Islands
Both the nation of Samoa and American Samoa are islands in the region of Oceania. The nation of Samoa has a population of less than 200,000 and an area of around 2800 sq km – one of the smallest nations. American Samoa is an unincorporated U.S. territory located in the South Pacific Ocean. It consists of five main islands and two coral atolls. With a population of a little less than 56,000, it has a total area of around 200 sq km, roughly one-fourth the size of New York City. Given its geography, the entire Samoan islands are at severe risk from rising sea-level due to climate change. This sea-level rise was made worse after the region was hit by two earthquakes.
The Earthquakes
In 2009, the island nation of Samoa was stuck by 8.1 magnitudes, followed by another one of similar intensity. While one earthquake was triggered due along with the normal fault – as one tectonic plate collides with another, the other earthquake was due to the compressive forces within this zone. The resulting waves hit the region and left 180 dead in the nation of Samoa and American Samoa.
This event can be characterized as a Black Swan event. None of the geologists or scientists were able to predict that the two earthquakes will accelerate this phenomenon to such a large extent. The two back to back earthquakes were an unusual phenomenon in the first place itself.
On top of that, these earthquakes accelerated the rate of sea-level rise in this region. After the earthquake, American Samoa has seen subsidence (sinking of island) of more than 0.6 inches per year. This subsidence is only due to the sinking of the island as a result of the tectonic shifts underneath. Again, no scientist or researchers predicted this increase in the rate of subsidence. In fact, scientists did not have any knowledge about this phenomenon even after the event occurred. It was only a decade later, in 2019, that they found the extent to which the islands had sunk.
Lessons for the future
This event only reaffirms what we already suspect – “Mother nature is fickle”. This event precisely reiterates the importance of understanding the concept of Black Swan. In such a highly uncertain environment, where we are not able to predict such a massive earthquake, and take a decade to understand the consequences of those earthquakes, why do we stop ourselves from thinking about the worst?
The reason for that is because we constrain ourselves by thinking more about the probability than by the consequences of an event. In this case, it seems that researchers took comfort in their knowledge that the likelihood of occurrence of the earthquakes followed by a change in the rate of increase in sea-level was low. What they did not take into account is that if this event occurs, which it did, the consequences for the entire region comprising of the Samoan Islands will be adverse.
This event should be a lesson for us in our fight against climate change. Any event is at most “highly unlikely”, but that does not mean that it may never occur. In fact, we cannot even accurately compute the probabilities of such events. According to the Global Facility for Disaster Reduction and Recovery (GFDRR), the earthquake hazard for Samoa is classified as medium, which means that there is a 10% chance of potentially- damaging earthquake in the next 50 years. And yet, this region saw two occurrences just within a decade – the double earthquakes in 2009 and a 6.1 magnitude earthquake in 2019. Amidst such uncertainties, the question then is – Are we prepared for the worst-case scenario?
We are clearly not. A primary justification for this is the cost of this preparation. Yes, the costs associated with preparing for the worst will be much higher than those associated with preparing for the “most likely” outcome. But no cost is high enough when it comes to securing humanity’s future on this planet. And the sooner we realize the errors of our way, the less our future generations will have to pay.