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    The Haiti Earthquake: Science, Early Warning And Mitigation
    By Bente Lilja Bye | February 8th 2010 03:01 PM | 29 comments | Print | E-mail | Track Comments
    About Bente Lilja

    Earth science expert and astrophysicist writes about Earth observation, geodesy, climate change, geohazards, water cycle and other science related...

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    When we experience disasters like the earthquake in Haiti January 2010, we naturally ask the questions: Could we have known (early warning)? Could we have been prepared (mitigation plans)?


    Photobucket

    Haiti on the Hispaniola island in the Caribbean. Credit: USGS

    There is no simple answer to that, because it relies on many factors. Technically, Haiti could have  been better prepared, in the sense that we have the knowledge to build early warning systems and disaster mitigation plans. In the case of Haiti, scientists knew since 1998 (Timothy Dixon et al) that stress was building up fast and ready to cause 7.0 earthquakes any time. Please note that when it comes to earthquakes, any time means from 10-100 years, the timing is not precise. As newly as  2008 the information about an eminent earthquake was confirmed (by Paul Mann et al) at the Caribbean Geological Conference. These scientists, who use GPS to monitor tectonic plate  movements, informed the Haitian authorities about this danger. (see also this article). These two scientific papers are both input in the risk assessment element of an early warning system and mitigation plans.

    Early Warning and Mitigation

    The UN International Strategy for Disaster Reduction (UNISDR) has defined what and early warning system is. (UNISDR, Living with Risk-a global review of disaster reduction initiatives, 2004).

    In general terms an early warning is the provision of timely and effective information that allows individuals exposed to a hazard to take action to avoid or reduce their risk and prepare for effective response. An early warning system therefore consist of the following 4 elements:

    Risk knowledgeWarning ServiceDisseminationResoonse

    Risk Knowledge - Understanding and mapping the hazard; Warning Service - Monitoring and Forecasting impending events; Dissemination - Processing and disseminating understandable
    warnings to political authorities and the population; Response Capability - Undertaking appropriate and timely actions in response to the warnings.

    A glance on the graphic above tells us that knowing about the risk is only part of the picture. The political, economic and social conditions in Haiti made it difficult to establish such an early warning system. More importantly it prevented working out and implementing mitigation plans based on risk assessments, which is fundamental to reduce disasters. Mitigation plans would typically consist of urban planning that regulates the quality of  buildings as well as placements of schools, hospitals, pipelines etc. Knowing is pivotal but only part of the picture.

    In the program The Science Behind The Haiti Earthquake, I let the International Centre for Geohazards explain in more details how risk assessment is being done. I also talk to Prof. Tim Dixon from the University of Miami about the Enriquillo-Plantain Garden fault system  in the Caribbean and have Prof. Bill Hammond from the University of Nevada explain the difference  between the Haitian, Californian and Nevada's seismicity.




    Science and Risk Assessment

    From a purely scientific perspective, an earthquake is good news. Today we have so many sensors  installed picking up various signals from natural events, that analysis of the data will boost our knowledge. Seismic fault models can be validated or improved etc. An earthquake like we saw in  Haiti will not only fuel the scientific knowledge production, the observations and scientific results are also important input to an updated and renewed risk assessment of the area.

    Immediately after the Haiti earthquake the scientists mobilized. A group of scientists that has specialized on the Enriquillo-Plantain Garden fault (Tim Dixon representing the University of Miami  group, Eric Calais representing the Purdue University group and Paul Mann representing the  University of Texas group and others) sent a team of geodesists to do GPS field survey in Haiti. Food and  medicine are important, but not the only life savers. The fact that the National Science Foundation  supports this field trip is a good example on the hidden life saving economic and professional support the scientific community provides. In addition technical support  is being provided by UNAVCO, who also host the so-called supersite for the Haiti earthquake, a one stop site under the GEO umbrella where you can find near real-time data and analysis from groups involved in operating earth observation infrastructure, both in-situ and space-based, as well as modeling and analysis work.

    I recommend reading the geodesists live blog from the field trip for an excellent insight of the  pleasures, challenges and risks that scientists experience. 

    Haiti rubbleGPS in Haiti

    GPS field survey in the rubble after the Haiti earthquake. Photos: NSF GPS Team in Haiti.

    Mitigating future disasters

    Based on their extensive experience a number of UN bodies are engaged in rebuilding the Haitian  society. The Haiti earthquake has engaged scores of other groups as well and substantial relief support has been given from nations, organizations and people around the globe.  Some risk assessment experts, like Conrad Lindholm from the International Centre for Geohazards and NORSAR, a geo-scientific research foundation in Norway - or Brian Tucker from Geohazards International, suggest that some 10 % of these resources should be earmarked for disaster mitigation both in Haiti (Times on suggestions for  future mitigation in Haiti), but also for other mega cities with high risk and  vulnerability.

    Hagia Sofia, Istanbul, Turkey

    Hagia Sofia in Istanbul, Turkey. Photo: Bente Lilja Bye

    The vibrant historical city of Istanbul is one of these places. With its 11 million inhabitants situated almost right on top of a seismic fault in Turkey, the city sits on a natural hazard bomb that could blast anytime  creating a human, economic and cultural disaster of unprecedented dimensions. Just like in Haiti. Another megacity placed in an earthquake prone area is the Indonesian capital Djakarta. Are the authorities ready to handle a major earthquake there?

    World Mega Cities

    Urbanization makes us more vulnerable to natural hazards. World map of mega urban areas made by Nordpil for the UNECE report Catalysing Change.

    Useful reading – in-depth material
    Earthquakes deadliest disasters last decade

    Global assessment report on disaster risk reduction (2008)

    Global Geodetic Observing System

    Group On Earth Observations

    GEO has established so-called communities of practice where geohazards is one out of 11  communities.

    For more links check out The Science Behind the Haiti Earthquake.

    Linking back here: Ivytechearthscience: wiki.

    Selected references:

    T.H. Dixon, F. Farina, C. DeMets, P. Jansma, P. Mann, E. Calais, Relative motion between the Caribbean and North American plates based on a decade of GPS observations, J. Geophys. Res., v. 103, p. 15157 -15182.

    Mann, P., R. Rogers, and L. M. Gahagan, Overview of plate tectonic history and its unresolved tectonic problems, in Central America: Geology, Resources and Hazards, edited by J. Bundschuh and G. Alvarado, G., (volume 1): Taylor&Francis, London, 201-237, 2007

    Calais, E., Y. Mazabraud, B. Mercier de Lepinay, P. Mann, G. Mattioli, and P. Jansma (2002), Strain partitioning and fault slip rates in the northeastern Caribbean from GPS measurements, Geophys. Res. Lett., 29(18), 1856 doi:10.1029/2002GL015397.

    AGU open access Caribbean plate papers.


    The author is an expert on natural hazards. She co-convened a section on Natural Hazards at the American Geophysical Union Fall meeting 2009 and has worked on diverse aspects of natural hazards ranging from science to politics.

    Comments

    An excellent article about Earthquake early warning and mitigation, Bente. I enjoyed watching the video which answered several questions I had about the fault system in and around Haiti, such as is it a right or left lateral fault. Also, it's encouraging what they're doing with GPS.

    I also read the geodesistslive blog from the field trip and found it quite interesting. I plan on visiting the other sites to which you provided links, but before I did, I just wanted to tell you first how much I appreciate your article. Thank you.
    Stellare
    Thank you Eric! There are quite a few links in this article, so if you plan to click your way through, some time will be consumed. :-)

    I've included links or references to other articles here on SB, including yours (more rock focused :-)), in this one too. All in all, the readers should be able to look at the Haiti earthquake from different angles. Which is good, I think. :-)

    I think it is so cool that they write a blog from the GPS survey in Haiti. We all get to see how the work is being done - and all the obstacles they encounter. Field survey is in any circumstances cumbersome at times. In a disaster area, you can only imagine - or read the blog! - how that must be. :-)
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    Yes, I agree about the blog from the GPS survey. Some of those ladders looked quite precarious. And it didn't look like too much fun when Sarah had to slip by that barbed wire on the roof of the police station in Desdune. You have to admire these people for the work that they do! :-)
    logicman
    A great article Bente.   Both of them!  (private joke.)
    Stellare
    Thanks for the kind words, Patrick. And also thanks for notifying me about my over productivity. hahaha
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    I have worked in my federal government in emergency preparedness and it's not an easy sell to get people to spend money and dedicate staff time for training to get prepared.

    Until big disasters happen.

    No matter where on earth you live, nature can get you whether it's earthquakes or tsunamis or hurricanes or tornadoes.

    Building codes, city planning, educated population and a warning system - even a short warning to prepare or flee.
    Caches of supplies...
    but mostly to get people to understand that most causalities happen after the quake when would be rescuers rush into unsafe buildings which then collapse on the trapped people and rescuers.

    Stellare
    Hi Nina,
    You underline an important point:
    "it's not an easy sell to get people to spend money and dedicate staff time for training to get prepared.


    Until big disasters happen.
    "

    This is why I also support what both International Centre for Hazards and Geohazards International (that is two separate organizations) suggest, namely to use 10% of the relief money to mitigation work.

    Thank you also for adding another point, namely the dangers in the aftermath of the quake itself. In my video Dr. Amir Kaynia from the International Centre for Geohazards tells us that in the Wenchuan earthquake in China 2008, some 25 % of the casualties was caused by the landslides triggered by the quake, and not the quake itself.

    Unfortunately, I fear that we will experience more mega disasters before we mobilize enough resources (that is both economic and human) to dramatically reduce the losses.
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    Thank you also for adding another point, namely the dangers in the aftermath of the quake itself. In my video Dr. Amir Kaynia from the International Centre for Geohazards tells us that in the Wenchuan earthquake in China 2008, some 25 % of the casualties was caused by the landslides triggered by the quake, and not the quake itself.

    That's another good point, Bente. And to a large extent that is a problem which could be avoided.

    A good deal of the time people create the conditions ripe for landslides, e.g., removing indigenous flora, the root systems of which have a stabilizing influence on lands that are sloped, building homes on cliffs or other unstable geologic formation just for the view (you see a lot of that in southern California), etc.

    Sometimes, however, landslides are unavoidable, e.g., where you have more easily eroded rock layers underneath more erosion-resistant rock layers--the structural integrity of the more erosion-resistant layers having been compromised by the erosion of the underlying rock layer. But even so, it still not a good idea to build underneath these areas, even if they were created by natural processes as opposed to human interference. Road-cuts also can create a landslide hazard. Many things to think about when considering Earthquakes. : )
    Stellare
    The geology of the place you live as well as the material your house is built with illustrate the complexity and multidisciplinarity of disaster mitigation. You go somewhat more in details on a few issues in your article here on SB. (link for the convenience of the readers :-))

    In your comment you also add on to what Amir Kaynia from the International Centre for Geohazards touches upon in the interview with me in the video. The rocks count in ways most people are not aware of. :-)
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    logicman
    Something that amazes me about design in earthquake-prone areas is the apparent fragility of infrastructure.  Even where rigidly enforced building codes make buildings survivable, roads, gas and water pipes, telephone and power lines, all seem much more vulnerable than the average building.

    After an earthquake it is absolutely vital that infrastructure is available for search, rescue and aid distribution workers to use.  I think that more work needs to be done in this area.


    Image source:
    http://tokyo5.wordpress.com/2009/01/17/kobe-earthquake/
    Stellare
    Thank you for enhancing the importance of considering the infrastructure when making mitigation plans.

    There are so many of these infrastructures we take for granted in our everyday lives, we -or even urban planners some times, have a hard time including them in our thoughts or when making plans.

     I believe that these issues are high on the priority list of UNISDR (UN International Strategy for Disaster Reduction) that gather information so that what one country or region have learned can be passed on to others.
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    That is a bit more difficult with long continuous structures like tiered highways and in some cases certain bridge structures than with houses and hi-rise buildings, and I'll attempt to explain why, Patrick.

    In the article to which Bente referred, I talked about why S waves are so much more destructive than P waves. A part of it is their greater amplitude, but a part of it is that they're transverse or shear waves as opposed to compressional waves. Now an S wave can either move laterally with a shaking motion or it can move up and down in a rolling motion, depending upon its orientation to the Earthquake focus.

    A long stretch of road covers more area linearly than say a house or hi-rise building. An Earthquake resistant house or building could ride out a rolling S wave in a way that an elevated or two-tiered highway cannot, simply because it occupies a smaller linear area. In the photo, that you so graciously provided above, it seems quite evident to me that this tiered highway was subjected to an S wave with an up and down rolling motion, hence the accordion-like appearance. But there is something else.

    There is a type of shock-wave specific to a strike-slip lateral fault that only recently has been recognized. Its a phenomenon known as 'supershear'  and it is analogous to a sonic boom. But instead of a sound you get a seismic boom! I believe such a phenomenon was responsible for the destruction in Haiti. But in order to do justice to this phenomenon I have to write another article. Los Angeles is subject to supershear because 1) it's on strike-slip right lateral fault and 2) because of the crustal material 200 miles south of Los Angeles, namely the very strong but brittle intrusive igneous, granite. But like I said, this is rather involved, and I'm afraid I've just committed myself to writing an article about it. LOL
    LOL Bente! We must have posted at the same time! ;-)
    P.S. But before I start on another article, I'm going to eat my dinner first! LOL I probably should make a pot of coffee as well--a scientist's best friend! hahaha
    Stellare
    The dinner must have been good, because your article is excellent! :-)

    Super Shear Earthquakes - Deadlier Than Deadly.

    (I have forced it in my list of relevant articles on SB - it sometimes needs a little helping hand that algorithm. :-))
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    Thank you, Bente. I appreciate that. : )
    logicman
    I look forward to your new article Eric.

    The problem is, as you say, continuous structures.  Perhaps the whole design concept of overhead highways in earthquake zones needs to be reconsidered.  At a glance, it seems to me that the picture shows two failure modes: a vertical folding at expansion joints and a horizontal failure similar to the tay bridge failure.  I have seen other pictures from Japan which show an almost S shaped failure mode of concrete bridging sections from, apparently, horizontal shock loading.


    For the benefit of any Australian readers, a supershear is not a productivity enhancing tool for sheep farmers.  Not by a long chalk!
    http://en.wikipedia.org/wiki/Supershear_earthquake
    Stellare
    Thanks for the comments - and further cool intel, Patrick! :-)
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    LOL about the supershear joke with respect to the sheep farmers down in Australia, Patrick! ;-)
    I see they have added more to the NSF Geophysicists in Haiti blog, Bente. I enjoy reading about their activities each day. I'm beginning to feel like I know these people.

    The citadel kind of reminds of an old Spanish fort that I visited many years ago in old San Juan while I was in Puerto Rico. The Caribbean islands are by far some of the most beautiful places I have ever visited. And, I loved swimming in the Caribbean sea. The geology is quite fascinating as well.

    It was interesting reading about the "teaching session" that they had with the Haitian high school students, although one question was a little disturbing: "Did the US military cause the earthquake? (No)." It is unfortunate that a child would have such an impression of the U.S., although I can understand it in light of the kinds of things that took place during the 8 years of the previous administration. But it is good to see such attentive and inquisitive young minds. ;-)
    Stellare
    The GPS Team blog is excellent. They just posted their last article as they are headed home to analysis their data catch.

    I thought the 'ladder' post was funny. They seem to have been able to keep a positive spirit in spite of the hardship they must have both seen and experienced some of themselves.
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    An Earth-quake causes heavy loss. Experts call for taking adequate precautions to minimize losses. Alarmed by the recurrence of quakes during recent years, should be taken as a signal for a major earthquake.

    Stellare
    The GPS team that was just finishing their surveying work will start analysis of the data and update the risk assessment. It is an ongoing process for all earthquake prone areas, but particularly urgent when there has been a large earthquake.

    It looks like earthquakes can migrate. That is, if you have a major earthquake one place the stress and strain seem to move to build up somewhere else on the same plate system. Note that it is not understood as a random process.
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    Unfortunately, that's quite true, Bente. If you have a series of faults along a plate, a large Earthquake like the one in Haiti can transfer its stresses to other faults in the area just by virtue of the displacement of rock that has taken place as a result of the Earthquake. It's a kind of a domino effect. We'll just have to see what happens.

    In the last blog entry I was inspired to read about people like Gregory Chevry, who is doing so much to help the victims of the Earthquake. It is most unfortunate that the corrupt government in Haiti quashed the election when he was drafted by the Haitian people to become a Senator. But it is still good to know that there are good and descent people like Gregory Chevry still in the world. : )
    logicman
    An Earth-quake causes heavy loss. Experts call for taking adequate precautions to minimize losses. Alarmed by the recurrence of quakes during recent years, should be taken as a signal for a major earthquake.

    Beauty Salon Plano (not verified) | 02/16/10 | 08:53 AM
    Stellare
    I agree that there is a more than 50 % chance that the Beauty Salon Plano is a spammer rather than having a genuine interest in earthquakes, relief or mitigation. However, there is no contradiction in being preoccupied with beauty AND being deeply interested in earthquakes. So I give them the benefit of a doubt. (I choose not to visit the link though - hahaha).

    Thank you for caring though, Patrick. :-)
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    What a fascinating discussion!

    I too have found your article very helpful, Bente. I teach Geography in Ireland to 14 to 18 year old students and I'm doing a topic on tectonics with my 18 year olds now. I've been researching the Haiti earthquake as a case study when I came across your blog.

    In particular, I found your early warning system graphic very useful. Our syllabus requires us to look at earthquake hazard management under three headings: (1) knowledge of the potential threat amongst the scientific community; (2) perception or awareness of this knowledge by the authorities and general public; (2) the level of development of the country in question. Your classificaion fits very nicely into this and has given me some more useful information for my pupils.

    I have one question for you. In my research, it has become apparent that the scientific community had reasonably good knowledge of the immanent earthquake threat in this region; in addition, the extreme poverty of Haiti is well documented. What I'd like to get more information on is the extent to which people on the ground in Haiti were aware of what the scientists knew; or, as you put it, how effective was the 'dissemination of understandable warnings'? I have found some material on building codes in Haiti here (http://haitirewired.wired.com/profiles/blogs/one-of-haitis-few-earthquake), but what about other aspects of preparedness such as earthquake drills, or education on what to stockpile for a quake, or what to do in the immediate aftermath? I know you guys have discussed this in general above, but do you have any specific information about Haiti suitable for a case study of their actual practice?

    Thanks again - I've enjoyed eavesdropping on your conversation. Although I must say I didn't expect to find you academics so fond of your 'lol's and ;-) !!

    Fitzgabbro
    Good article.

    I think it is important to contrast Haiti to other parts of the world which are prepared for earthquakes.  The recent Christchurch earthquake gives a perfect example of what can be done, a much larger quake than Haiti but no deaths.  Just in case anyone thinks these preparedness measures are futile and a waste of time and money.  Large earthquakes don't have to have large death tolls
    Stellare
    Note to self: https://www.e-education.psu.edu/geog030/node/402
    This article has been used by students in the course GEOG 030 at Penn State.
    http://www.psu.edu/dept/e-education/blogs/geog030/2012/02/module-5---dev...
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth