I enjoyed the visit at the Department of Civil and Environmental Engineering at Princeton University. I have had great discussions with Professor Lin and her Hurricane Hazards and Risk Analysis Research Group.
I am honored to be invited to give a seminar talk, entitled "Understanding Human Judgement on Environmental Risks and Hazards in a Geographic Context," at the Department of Civil and Environmental Engineering at Princeton University on June 21.
The abstract of the talk is as follows:
"The coupling effects of changing climate and rising concentration of population and assets in the coastal regions have increased the threat of potential damages. There is an urgent need for coastal communities to prepare well for future hazards through mitigation and adaptation measures. A growing number of empirical studies have found that peoples’ motivation of voluntary risk mitigation and adaptation is low unless actual risk can be perceived. Risk perception is thus the precondition for adaptive behavior. It is of both intellectual and practical interests to study what affects individuals’/communities’ risk perceptions. In this talk, I will present four of my previous studies. The first three studies are focused on the individual level and the fourth on the aggregate level. I will start with understanding how local weather and climate affect American public risk perceptions of climate change. I will then discuss how the spatial context represented by past flooding events and estimated flooding risks influence costal residents’ voluntary flood insurance purchase decisions and their support for flood adaptation policies. As many policies are designed and implemented at an aggregate level (i.e., state, county, city), it is necessary to examine aggregate-level risk perceptions. In the fourth study, I will focus on how the contextual hurricane risks in conjunction with community resilience shape county-level perceptions of hurricane-related risks. I will end with a research agenda linking communities’ perception with contextual risks and community resilience. I contend that the cognitive dimension including both risk perceptions and perceived adaptive capacity is not represented in any of the existing community resilience indexes, and therefore needs to be measured, quantified, and incorporated into a more comprehensive index."
Hurricane Harvey dumped record-breaking rain in Houston in 2017. Now, a new study shows that this extreme amounts of rainfalls actually resulted from unprecedented ocean heat content. This study presents some evidence to support the link between global temperature rise with increasing hurricane intensity.
Our new paper on aggregate perceptions of hurricane risks has been published on the Annals of American Association of Geographers.
I presented our study on community resilience and county-level perceptions of hurricane risks along the US Gulf Coast at the 2017 Society for Risk Analysis annual conference in Arlington, VA.
In a study that has been accepted by the Annals of the American Association of Geographers, my coauthors and I have examined how community resilience along with objective hurricane risks impacts aggregate perceptions of hurricane risks. We first applied spatial techniques to transform individual-level perceptions to the aggregate level, in this case, counties. The map below displays the geographic pattern of hurricane risk perceptions among coastal counties along the U.S. Gulf Coast. Clearly, there is a concentration of heightened hurricane risk perceptions stretching from southeast Texas to west Florida. Given the recent enormous impact of Hurricane Harvey in southeast Texas and West Louisiana, it is likely that risk perception has further increased among coastal residents who have been affected by Harvey.
Further, we found two aspects of community resilience measured by Cutter et al. (2014), namely economic resilience and community capital, are positively related to aggregate perceptions of hurricanes risks. This indicates that communities with more economic resources and social capital tend to perceive greater threat of hurricanes. The policy implication is that counties with less economic and social capitals need to direct efforts on educating the public about scientific assessments of hurricanes risks.
Cutter, S. L., Ash, K. D. and Emrich, C. T. 2014. The geographies of community disaster resilience. Global Environmental Change, 29, 65-77.
Shao, W, Gardezi, M., and Xian, S. (forthcoming). Examining the effects of objective hurricane risks and community resilience on risk perceptions of hurricanes at the county level in the U.S. Gulf Coast: An innovative approach" Annals of the American Association of Geographers.
After Harvey dumped over 40 inches of rain in Houston over a few days, the city must come to the realization that it cannot continue to be built and relentlessly expanded by ignoring science. Now, it is time for the city to rethink about its development plan and hazard mitigation policies.
I just published an analysis piece on Hurricane Harvey and its policy implications on the Conversation.
Here is the last paragraph, "Given the devastation Harvey has incurred among coastal residents in Texas, we expect that these communities will be shell-shocked in the foreseeable future. This heightened risk perception will translate into adaption and mitigation actions. If another big storm hits Texas in the near future, residents will be more ready. New Orleans, where local officials issued detailed instructions last week about preparing for Harvey, is a perfect example for Houston to follow."
The wind has diminished. Now the great threat of flooding is looming over Houston as unprecedented heavy rainfall is pounding this area. In order to cope with flooding, there are some precautionary measures for coastal residents to adopt. I am re-posting two of my old blog entries here:
"One effective precautionary measure would be to purchase flood insurance. In reality, though, only a portion of these coastal residents who live in the imminent threats of floods have flood insurance. Naturally, we start to scratch our heads and wonder, "what drives people to buy flood insurance?"
Driven by this question, my co-authors and I analyzed the Gulf Coast Climate Change survey data merged with contextual data, and made several important findings on individual voluntary flood insurance purchase behaviors. The results are published in the journal: Water Research
These findings include:
1. Flood risks in FEMA flood map affect the voluntary purchase of flood insurance.
2. Voluntary behavior is influenced by perceptions of flood-related risks.
3. Intensity of the local flood events in the past affects the voluntary behavior.
4. Social factors especially income significantly affect the voluntary behavior. "
"Purchasing flood insurance may relieve financial burden for home owners after a big storm hits. With the deeply troubled National Flood Insurance Program (NFIP), it is sensible for home owners to think of alternatives. By utilizing original survey data merged with contextual data on flood risks, my coauthors and I have investigated the determinants of coastal residents' support for two adaptation policies: incentives for relocation and funding for educational programs for emergency planning and evacuation. The major finding of this study is that perceptions of flood-related risks plays an essential role mediating the contextual flood risks and adaptation policies. The contextual risks, indicated by distance from the coast, maximum wind speed and peak height of storm surge from the last hurricane landfall, and percentage of high-risk flood zone per county, do not directly exert influence on policy support. Instead, these contextual risks impact one's adaptation policy support through risk perceptions. This finding implies the significance of risk perceptions and highlights the need for effective and accurate risk communication. This study has also been published on Water Research. "
The National Flood Insurance Program (NFIP) is in deep debt, owing billions of dollars to the U.S. Treasury after monstrous Hurricane Katrina (2005), Super Storm Sandy (2012), and Louisiana Epic Flood (2016). This program was first passed by the Congress in 1968, with the initial intention to entice coastal property owners to join this program by providing subsidies. In doing so, the premiums paid by property owners are distorted and do not fully reflect the real flooding risks they have to deal with. The misleading price signal unintentionally encourages property developments in risky areas, such as the Special Flood Hazard Areas (SFHA). In anticipation of rising seas and stronger coastal storms, rebuilding efforts seem to be on the path to further drive NFIP off the cliff.
Purchasing flood insurance may relieve financial burden for home owners after a big storm hits. With the deeply troubled NFIP, it is sensible for home owners to think of alternatives. By utilizing original survey data merged with contextual data on flood risks, my coauthors and I have investigated the determinants of coastal residents' support for two adaptation policies: incentives for relocation and funding for educational programs for emergency planning and evacuation (Shao, et al., 2017). The major finding of this study is that perceptions of flood-related risks plays an essential role mediating the contextual flood risks and adaptation policies. The contextual risks, indicated by distance from the coast, maximum wind speed and peak height of storm surge from the last hurricane landfall, and percentage of high-risk flood zone per county, do not directly exert influence on policy support. Instead, these contextual risks impact one's adaptation policy support through risk perceptions. This finding implies the significance of risk perceptions and highlights the need for effective and accurate risk communication.
Shao, W., Xian, S., Lin, N., and Small, M. J. 2017 "A sequential model to link contextual risk, perception and public support for flood adaptation policy." Water Research. doi.org/10.1016/j.watres.2017.05.072