Predisaster risk encompasses the potential threats such as tornatos, violent storms, earthquakes, etc. That is usually assessed with historic records. What is a predictor of the effects that such a disaster would pose to life and society would be through through planning. Looking at the rescue and recovery of the history of disasters we find that it is measured through the dollar amount of damage, the number of fatalities, those people displaced and the physically injured. A more accurate measure would include information on the people who need assistance in terms of loss, psychological problems dealing with loss, and the rate that immediate and long term aid is given. An overall assessment would be transparent as to who receives aid and the success and failure to address the needs of vulnerable populations such as race, age, socioeconomic status, disability and those who are on public assistance. What happens to those people?

Hi Jessica, One resource I really like on this subject is Jorn Birkmann's "Measuring Vulnerability to Natural Hazards" http://unu.edu/publications/books/measuring-vulnerability-to-natural-hazards-towards-disaster-resilient-societies-second-edition.html#overview. It outlines some of major recent initiatives and unpacks the question at different scales (from Global, National, Sub-national to Local). Hope it helps!

Dear Jesseca, I would like to add some additional references. Firstly, as Davide and Nicole have been evidenced, the risk R assessment is based on three pillars: hazard H (connected to the kind of event), vulnerability V (connected to structures and infrastructures), exposure E (connected to human factor and "value" of elements). The Ambresey's definition traces their dependencies in order to evaluate the risk for a specific catastrophes, both man-made and natural hazards (Ambraseys, N., 1983. Evaluation of seismic risk. In: Proc. NATO Advanced Studies on Seismicity & Seismic Risk of the North Sea. Reidel, Utrecht, pp. 317–345).

While the first two parameters essentially involve the analysis of environment factors and have been inquired since a long time (e.g.: for the earthquake vulnerability you can see http://refhub.elsevier.com/S0925-7535(13)00223-3/h0030), the exposure parameters is deeply investigated in those last years. E includes the human behaviors and sociological aspects (http://refhub.elsevier.com/S0925-7535(13)00223-3/h0035; http://linkinghub.elsevier.com/retrieve/pii/S0925753513002233): people interacts with the environment before and during the catastrophe and the exposure parameter investigation really influences both the analysis of risk and the emergency response, for example in terms of society resilience (Cutter SL, Barnes L, Berry M, Burton C, Evans E, Tate E, et al. A place-based model for understanding community resilience to natural disasters. Glob Environ Change 2008;18:598–606 - http://refhub.elsevier.com/S2212-4209(14)00064-8/sbref20). Moreover, the population characterization, as also suggested by Nicole, is one of the most important issues that have to be inquired. For this reason, innovative tools are actually developed in order to include E in the R assessment. Our research group is involved in similar studies, with the aim to define tools and rules for a full and operative risk assessment definition. I hope I will can give you some more accurate suggestions as soon as possible!

Professor Kline, thank you for your response.  That is a very good question that is receiving little attention. Examining all dimensions of recovery--economic, social, political, physical, ecological etc., is necessary to implement mitigation strategies in vulnerable areas, as well as to vulnerable people. Thank you Professors Matyas and Bernardini--these references are certainly helpful in providing understanding of what to include in the risk models. 

Do it Yorself....

Risk = [(System Vulnerability + Exposure degree) / (Coping ability)] * Threat

Dear Cesar San-Juan, 

your formulation seems to be really interesting! Could you suggest some references in order to take a deeper look into the matter? Thank you very much in advance!

Hi Jesseca - risk assessment (i.e. estimation of expected loses per given time period) is not trivial. I would like to stress that while a lot of work on risk has been done in different disciplines, essentially all components of risk (the hazards, elements at risk, exposure, etc.) are spatial in nature. This means that approaching risk from a geoinformation science perspective (using, for example, remote sensing data, geographic information systems or spatial modelling tools, geostatistics, etc.) is suitable. Together with colleagues a few years ago I wrote a Multi-Hazard Risk Assessment Guide Book (see http://tinyurl.com/py62agz) that is entirely written from a geoinformation perspective, and provide a wealth of detail on all aspects of risk assessment. On my ResearchGate profile you also find many more paper, book chapters etc. on different specific aspects, as well as other overview-type book chapters. Hope it helps.

Norman

Dear Jesseca

Actually there are some general misunderstanding about measuring risk in natural disaster management. As a matter of fact calculating risk has a certain formula in mathematics and also applied in insurance and project management field and also reflected to disaster management. 

Risk= Impact   x   Probability

It means you can measure risk only through this condition and if you be able to properly and accurately calculate "Probability" of any events or natural disasters and also if you could know about its "Impact" therefore you could have the risk amount. 

In the other point of view in disaster management we heard about the following formula:

Risk= (Hazard x Vulnerability  x Capacity) /  Preparedness

In this concept whenever your elements are qualitative you could not properly use quantitative approach. So from this formula you cannot logically be able to calculate risk even you have all this information in quantitative way. 

All that we talk about in disaster management in some cases can be measured if we have for example information of buildings and faults or generally in seismic risk calculation and so on. But when we talk about readiness of a community or capacity of your DRM in governmental structures then you cannot easily calculate it by simple criteria. 

In the other hand there are direct relation between risk and uncertainty situations and Warren E Walker imply in a paper called Deep Uncertainty, there are five levels of uncertainty and just in two of them we could able to statistically measure the risk in other levels of uncertainty we need deeper methods to measure, like scenario development and all other qualitative methods that we usually used in foresight studies.

Best,

Ardeshir

Jesseca,

As you are starting you focus your studies about disasters, I suggest you think that risk is the probability of loss any resource by some hazard. First of all you need understand the dangerous process studied and define the spatial reach to find what can be affected by this process. Then you need calculate the probability of this dangerous process can occur. Usually the result is something like deaths or US$ (currency) per time (eg. day, month, decades...) due the dangerous process. This analysis is quantitative, but you can use a relative analysis called qualitative where you compare relatively the results. This results could be expressed as low, medium or high.

When you understand better this idea, you can add to this equation some index to adjust the results depending of the characteristics of the elements involved. This index sometimes are called vulnerability, time exposition, etc...

Have a good luck, this study area (risk and disasters) are very interesting.

Regards,

Francisco