Earthquakes can aggravate sea water level rise

According to a new study published in the Journal of Geophysical Research: Solid Earth, earthquakes can cause sea level rise even faster than climate change. 

Researchers believe that certain regions, including islands in the Pacific Ocean, should be alerted as sea level may be rising quicker than previously thought.

In September 2009, 2 massive earthquakes struck off the coast of Samoa Islands triggering a powerful tsunami that hit the coast. Authorities reported severe structural damage and more than 180 fatalities in the region. In addition, according to the new data, the earthquakes have caused the water level to rise five times faster than before. 

Of course, earthquakes are not correlated with ice melting but with another mechanism that makes the water level to rise. In particular, the shocks caused the Islands to begin sinking in the Earth's crust and therefore the differential displacement causes the water levels to change. It is estimated that sea levels can rise by about 0,3 meters more than they would, considering only the climate change effect, over the following 50-100 years.

The study emphasizes on the fact that earthquake effects are not the same throughout the planet but, in some cases, they can be devastating. We conceive geology processes as extremely slow and harmless to human environments but this is an exception that needs to be severely considered. “Everybody is talking about climate change issues ... but they overlooked the impact of the earthquake and associated land subsidence," Shin-Chan Han, Professor at the School of Engineering, University of Newcastle, Australia and leader of the study, stated.

The team used images and satellite data to show that American Samoa and Samoa are subsiding at a rate of 1,6 cm and 0,8-1,0 cm, respectively, annually.