We've talked a little about the methods used to analyze, and thus prepare and respond to earthquakes, volcanoes, and other hazards, but they are so important to the management of these natural events and the protection of those that are in danger, that we must look at them as a whole. Pay close attention to the methods...they are vital to your understanding of natural disaster management. Of course, MEDCs will have more advanced techniques than LEDCs, but both should make use of the best techniques available in order to ensure maximum survival and least destruction.
In the parentheses, "e" will stand for earthquake, and "v" will stand for volcano analysis methods.
Historic Records (e,v)
This one is kind of obvious...but it is important. Record-keeping is vital to determining where strong earthquake and volcanic activity has happened...because those places are at the most risk. As you saw in the plate boundary activity, the historical locations of earthquakes and volcanoes have also led us to determine different plate boundaries, and thus determine where the highest level of activity occurs. Historical records are more accurate in MEDCs, so they have a better chance of aiding in prediction.
Frequency (e,v)
For earthquakes (from USGS website): "Scientists study the past frequency of large earthquakes in order to determine the future likelihood of similar large shocks. For example, if a region has experienced four magnitude 7 or larger earthquakes during 200 years of recorded history, and if these shocks occurred randomly in time, then scientists would assign a 50 percent probability (that is, just as likely to happen as not to happen) to the occurrence of another magnitude 7 or larger quake in the region during the next 50 years."
This may not be the case, however, as after a slippage, another earthquake may be more likely to occur sooner in the prediction model.
For volcanoes, pretty much the same is true as for earthquakes. If an area has experience frequent volcanic eruptions, it is assumed that it has a higher probability of eruption than a place that does not. Once again, however, this is not a very reliable prediction method, especially when it comes to explosive eruptions that have built up over time. There is always a first eruption, and it may be the worst!
Seismic Evidence (e,v)
Once an earthquake happens, the seismic evidence can let us know where aid is needed by looking at the difference between times of the s and p-waves. Refer back to the earthquake virtual lab to learn more about how exactly this occurs. You should be an expert by now! Of course, knowing where the most damage may be, and also where tsunamis may go, can be a great help in providing aid and relief.
For volcanoes, this is reliable information found on Wikipedia...yes, sometimes it is useful! "
Seismic activity (earthquakes and tremors) always occurs as volcanoes awaken and prepare to erupt and are a very important link to eruptions. Some volcanoes normally have continuing low-level seismic activity, but an increase may signal a greater likelihood of an eruption. The types of earthquakes that occur and where they start and end are also key signs. " You can read more about using seismic activity as a predictor for volcanoes in Seismic Waves part on the on the volcano prediction Wikipedia site here. Basically, tremors near a volcano can be a great predictor of eruptions.
Tilt Metres (v)
Read the Wikipedia article on tiltmeters here...best thing we have to predict volcanoes.
Chemical Analysis (v)
Increasing amount of sulfur dioxide in the air can predict that a volcano will erupt, as it is a main component of the effusive gas in an eruption. The stronger the concentration gets, the more likely it is to explode soon.
Building Design (e)
As we saw in class in the TED Talk on the Haiti earthquake, sound building design is imperative to protecting a population from earthquake disaster. Properly built structures, with tied rebar and symmetric design are much more likely to hold up than those "built on the cheap." Investment at the beginning can lead to much less of a human disaster from building collapse. You can view the TED Talk again here.
Rescue and Aid (e,v)
There are many different organizations that assist in the rescue and aid of volcano and earthquake victims. As we have seen, however, MEDCs tend to get quicker response because it usually is an established group/government from within the country providing aid, while LEDCs rely on the organizations or governments in the MEDCs for aid. This provides for not only slower response, but also limited supllies in LEDCs. The combination of the slow/limited aid, worse prediction technology, and poor building structure puts the LEDCs at a much higher risk of devastation from earthquakes and volcanoes than MEDCs.
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