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The case for case studies: a natural hazards perspective

As I wander the streets of Easton, as I have done over the last 18 months, the landscape becomes more and more familiar. Same streets, same skies. Things seem flat and still.  

Living in this mundane landscape, I find it hard to believe that we live on a turbulent, roiling planet. But the Earth is not flat or still! Natural events happen daily, and extreme climatic events continue to escalate – although all we see in England is a rainy July. Some people are more vulnerable to the Earth’s vicissitudes than others. Since 2021 began, volcanoes in the Democratic Republic of Congo, Italy, Guatemala, and Iceland have erupted, and hurricanes have already gathered pace in the Atlantic. Many of these events have caused disaster for people living in these areas, losing homes, livelihoods, and lives.  

Disasters erode and destroy, they leave scars and memories. We are fascinated by them: we seek to understand and to explain. How can we best do that? The case study is one way. Because of its in-depth nature, a case study is well-suited to describe disasters caused by natural hazards (earthquakes, volcanoes, landslides, floods, droughts), allowing us to tell a rich and nuanced story of events. However, we have to be prudent. There are many more natural hazards than we have scope to investigate. A good subject for a case study offers the possibility of new insights that other, limited methods have missed. Many, many times an earthquake or flood does not cause disaster. In choosing a good subject for a case study, we are looking for that event which is particularly interesting to us, and which we hope can tell us new things.  

I am currently working on three case studies of disasters in Guatemala. Why and how did the disasters happen?  

Coming from an Earth Sciences background, I’m not sure where to begin. There are no obvious blueprints. Why is there so little guidance on how to do a case study in our field? I think there are two reasons. Earth Sciences has always generously included other physical and social sciences (physics, chemistry, mathematics, geography), while a disaster caused by natural hazards involves both physical and social factors. So while this supports disaster’s suitability to the case study method, both science and subject use multiple philosophies and methods. It’s harder to make a cookbook with mixed methods. Secondly, Earth Sciences looks at the mutual interaction between people and nature, who operate on different timescales. Tracing a disaster through a case study requires uniting these timescales in a single narrative. That union is a difficult task and often context-specific, so not generalizable to a single blueprint. (Strangely, in an interdisciplinary case study of a disaster it’s the physical scientists who seem to study events over shorter timescales, for example on the physical triggers of a volcanic eruption. A few years ago in my undergraduate I remember tracing the story of Earth’s evolution across billions of years; now we’re operating over days and hours!) 

There have been many criticisms levelled at case study research: that you can’t generalize from a single case, that theoretical knowledge is more valuable than practical knowledge, that case studies tend to confirm the researcher’s biases [1]. I have also read that case studies are excellent for qualitative research (e.g., on groups or individuals), but less so for quantitative research (e.g. on events or phenomena) [2]. I think these points are rubbish. 

“You can’t generalize from a single case”, goes the argument against case studies. But generalization is not the point of a case study. We want to go deeper, to know more intimately, to sense in full colour. “Particularization, not generalization” is the point [1], and  intimate knowledge is worthwhile in itself. However, I also think the argument is false. Because it is such a rich medium, the case study affords us a wealth of observations and thus interpretations that allow us to modify our existing beliefs. As an example, a case study of the Caribbean island of Montserrat during an eruptive crisis showed Montserratians entering the no-go zone, risking their lives from the volcano to care for their crops and cattle [3]. This strongly changed the existing reasoning that people would prioritize their life over their livelihood during a volcanic eruption. How could you deny that this finding is not applicable beyond the specific case study? True, it isn’t certain to happen elsewhere, but the finding reminds us to research with caution and to challenge our assumptions. A case study might not give us a totally new understanding of an event, but it might refine our understanding – and that’s how most science progresses, both social and natural. This ‘refinement’ is also a balm for people like me who might be approaching a new case study with trepidation, concerned we might be going over old ground. Sure we might, but here we might forge a new path, there dig up fresh insights. 

On the grounds of theoretical versus practical knowledge – we learn by doing! We are practical animals!  

Context-dependent knowledge and experience are at the very heart of expert activity.

(Flyvbjerg, 2006)  

Does a case study confirm what we already expect to find? I think the possibility of refining our existing understanding can encourage researchers to keep our eyes open to distortions and bias. I think this final criticism comes from a false separation between the physical and social sciences. Qualitative research is held up as a contrast to “objective” quantitative research in the physical sciences, focussed on hypothesis-testing and disinterested truth. But any PhD student will tell you that the scientific process doesn’t quite work that way. Hypotheses are revised, created, and abandoned with new data, similar to how grounded theory works. And you can find any number of anecdotes where two scientists with the same data and methods came to two different interpretations. There is always some subjective bias as a researcher because (a) you’re also a human, and (b) because the natural world is inherently uncertain. (I wonder if this is an appeal for those who study pure maths – it’s the only discipline I can think of that is really objective and value-free).  Maybe qualitative/quantitative has some difference in the degree of researcher subjectivity. This would be a fascinating subject to explicitly include in those interdisciplinary case studies that involve both types of researcher – how does each consider their inherent bias towards the subject? 

After flattening those objections above, I really want to make three points as to why case studies are so great.  

First, they have a narrative element that we find irresistible. As Margaret Atwood said,  

You’re never going to kill storytelling because it’s built into the human plan. We come with it. 

A case study is not just a story, but it does have a story woven into its structure. Narratives are always partial and partisan; our case studies will be too. That’s not to say they can’t be comprehensive, just that they cannot hope to be omniscient. I love this quotation: 

A story has no beginning or end: arbitrarily one chooses that moment of experience from which to look back or from which to look ahead.  

Graham Greene, The End Of The Affair 

It certainly applies to case studies, too. We may find the roots of a disaster in political machinations which began decades before, or that the journey of a mudslide was hastened by years of deforestation. Attempting to paint the whole picture is futile, but you have to start somewhere.  

Second, a case study provides a beautiful chance to both understand and to explain – the aims of the qualitative and the quantitative researcher, respectively. Each may approach truth and theory differently: the first sees truth as value-laden and theory to be developed in the field; the second, as objective and to be known before work is begun. It’s precisely because it’s difficult to harmonize these worldviews that we should be doing it – and the disaster case study provides an excellent arena. 

Finally, the process of building a case study creates a space for dialogue. Ideas grow through conversation and criticism, and the tangle of researchers trying to reconcile their different worldviews, and of researchers reconciling their priorities with other interested people, seems both the gristle and the fat of case study research. In the case of disasters, I think this is the most important point which case study research wins. Research can uncover the most wonderful things but if it is not important to the people who are at risk of disaster, we cannot hope to effect positive change. How can we understand, and then how can we make ourselves understood? For all the confusion and frustration that it holds, we need dialogue [4]. A really beautiful example of this is the dialogue between volcano-watchers and scientists at Tungurahua volcano in Ecuador: creating a shared language allowed for early response to volcanic hazards and a network of friendships [5]. 

I’ve grappled with what products we should make out of these case studies. What are we making, and who are we making it for? From the above point, a valuable product of a case study can be a new relationship between different groups of people. This is not really tangible, which is hard to deal with for the researchers (how do you publish a friendship?) But a case study can produce a relationship that benefits both parties and outlasts the study itself. I think I’ve experienced this personally, through my work at Fuego volcano. I have found the opportunity to share my research and also to be transformed in my workings with local people. This has lasted longer than my PhD, I am still in touch with some of these people.  

I believe in the power of case study to its own end, to create dialogue, and to mutually transform researcher and subject. And, if a new relationship is a valuable product of the case study, it is made stronger still by continued work in that area. To do that, the relationships and the ties that bind need to be supported financially and socially across years and uncertainty, beyond the current grey skies and monotony. When we are out, we will be able to renew that dialogue in person and the fruits of our labour will blossom.   

[1] Flyvbjerg, 2006 

[2] Stake, 1995 

[3] Haynes et al., 2005 

[4] Barclay et al., 2015 

[5] Armijos et al., 2017 

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This blog is written by Cabot Institute for the Environment member Ailsa Naismith from the School of Earth Sciences at the University of Bristol. Ailsa studies volcanic hazards in Central America.

Ailsa Naismith


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