Chasing Tsunamis for Science

The scoop: Tsunami researcher Jose Borrero has seen the aftermaths of many tsunamis. He was one of the first to collect data in Banda Aceh after the devastating 2004 Indian Ocean Tsunami. He has some insights into tsunamis, and the study of them, that you'll likely not see anywhere else...

LarryO': Where are right now and why are you there?

JBorrero: Right now I am in Raglan, New Zealand. I am currently working for a consulting company called ASR Limited. I work on a variety of coastal consulting projects doing everything from tsunami hazards to coastal sediment transport and beach protection. We also design and build artificial surfing reefs and artificial reefs for coastal protection. I still do some work on tsunamis, mostly in my own time and just for fun.

LarryO': Oh yes, I've spoken with ASR folks before. A unique company. How did you come to study tsunamis?

JBorrero: I was doing a degree in Civil Engineering. I have always been a 'beach' kind of guy, surfing etc... so I wanted to study coastal engineering. In 1994 I was at USC (Univ. of Southern California), and one professor introduced me to Dr. Costas Synolakis who was working on hydrodynamics and tsunami runup problems. I got involved with his group and it was fun and interesting, so I stayed with it. The tsunami group at USC is now known as the USC Tsunami Research Center.

LarryO': How has your field changed since the 2004 Indian Ocean event?

JBorrero: That is an interesting question for me. In a way I think it has diluted the field. There have been a lot of people who were not into tsunami research before 2004 that all of the sudden saw it as an opportunity to get more research money. Some of those people were better connected in terms of access to funding and they sort of pushed a bunch of smaller and less connected (but no less dedicated) tsunami researchers out of the picture. Also, a lot of places that really had no tsunami hazard were 'manufacturing' tsunami hazards in an effort to tap into the funding.

The finite pot of tsunami research money in the USA was instantly diluted. The money was originally set aside for the US West Coast and Hawaii (5 states) then after 2004, the entire Atlantic coast and Caribbean region was added to that list for the same finite pot of money. The result was a lot less money available and much harder to get. So in my case, the 2004 event actually sort of ended my tsunami research career because I wasn't into fighting for money.

LarryO': That sucks. I seem to remember meeting you at AGU in a poster session -- years before the Indian ocean event. Seems there was too little attention on tsunami dangers then.
Before the funding troubles then, how do you know when there has been a tsunami and how do you go about getting to the scene quickly to study it?

JBorrero: Tsunamis are [mostly] caused by earthquakes. So the tsunami warning centers and interested research community members all monitor the earthquake detection networks. When a suitably large earthquake (greater than about 6.5 in magnitude) occurs somewhere in the ocean or on a continental margin, email alerts are sent out. The guys/gals who work at the tsunami warning center in Hawaii are on call 24 hrs a day, 7 days a week, 52 weeks a year so they are looking into the event within minutes. They then make a preliminary assessment based on the earthquake's size and details. Further messages are sent out to either continue the watch or warning or cancel it.

If the event looks to be capable of generating a tsunami, I generally just monitor the news networks and websites waiting for information on the tsunami. If it then turns out that it is something worth studying, groups of researchers will then coordinate or collaborate to go to the region to collect information on the tsunami such as wave heights, damage, inundation etc... There is nothing 'official' about this process, it is basically whoever is interested and can get there can go.

LarryO': Why is it so important to get to the scene quickly?

JBorrero: In smaller tsunamis, or tsunamis that happened in remote or sparsely populated areas, this is more important. The traces that the tsunami leaves behind, such as debris lines, can be eroded away in rainstorms or modified by the locals doing cleanup. Also the stories and anecdotes of the event tend to become a 'collective' memory rather than people's individual stories. So if you get there within a few days of the event, it is more fresh in their minds and you get more details in interviews.

In the case of Sumatra 2004, the event was so massive, time really wasn't of the essence. But we didn't know that at the time. We had no idea how big it really was. I was the first international scientist to see Banda Aceh first hand (my friend Gegar Prasetya from the Indonesian government marine science group BPPT was actually the first scientist to see Banda Aceh. He was there a day or two before me, but only had a quick look then left the city while the relief/recovery process was going on).

I was completely blown away when I saw Banda Aceh, I was totally unprepared for the scale of the destruction. Looking back I wish I'd had another researcher with me and a bit more equipment. We could have done a lot more data collection. But I did what I could in the few days I was there and I believe it set the stage and led the way for the rest of the field researchers to come in and collect more data. As it turned out people were collecting data on the tsunami for months after the event. The traces from that event weren't disappearing very fast!

LarryO': Have there been any breakthroughs in understanding tsunamis as result of the 2004 Indian Ocean event?

JBorrero: I'm not sure about breakthroughs. I think it is more of an acceleration of the continuum of understanding about tsunamis. The Sumatra earthquake was a very unique event. There have been several tsunamis since that event that have been quite destructive and deadly on a local scale that didn't attract any attention globally because they were relatively small compared to 2004. Like, what, only 500 dead? Who cares, that's not a tsunami, it had to be 10's of thousands before the news notices. It almost seems like to the average person, if a tsunami doesn't cause havoc over an entire ocean basin, then it really wasn't a tsunami!

But that isn't the case at all. The smaller, more localised tsunami events continue to be a bigger hazard to coastal residents who live in earthquake prone regions. It is these people by the way who do not benefit from the establishment of large scale warning systems. Those warning systems are set up to warn people who live several hours away from the tsunami source that a wave may be coming.

People who live in the source area are affected by the tsunami almost immediately, so a warning buoy that detects a tsunami an hour after it happens is pretty much useless for them, they are already dead. For these people the best protection is an understanding of the phenomenon, detailed inundation maps that show what areas are prone to flooding and a clear evacuation plan that can be implemented without thinking.

So the bottom line, still, is: If you live or are staying in an earthquake prone coastal region (i.e. US west coast, Alaska, Japan, South/Central America, east coast of New Zealand or Indonesia) and you feel a strong, prolonged earthquake, you should immediately head to higher ground for at least half an hour and monitor the situation. If there are any unusual water motions, a large withdrawal of the sea surface then a tsunami has probably been generated and people should remain evacuated and at safe elevations until the event is over, which can last for a few hours.

larryo: Thanks a million for your time. This is some great information. Cheers.

Article posted June 22, 2009.