Extreme weather events are opportunists. They strike indiscriminately, and selectively expose the parts of society that are underprepared and most vulnerable. We see the lack of resilience to extreme events in the most susceptible regions time and time again in the loss of life and livelihoods and the destruction of properties and businesses.
Hurricane Katrina was a very clear example of this, as described in my previous blog “Interactive Map of Hurricane Katrina”. The long-term degradation and loss of wetlands was a key factor that has made the region more vulnerable to storm surge, but the catastrophe was exacerbated by inadequate levee protection and overwhelmed response and evacuation procedures. The storm caused over 2000 deaths, the flooding of over 80% of the city and over $100 billion worth of damage.
Further examples are not difficult to find: the Japan earthquake and tsunami in 2011, the Haiti earthquake in 2010, Cyclone Nargis in Myanmar in 2008, and range from the geophysical to the climate-related. All of these events are unstoppable and will continue to occur in the future; in the context of a changing climate, some are likely to become more severe and/or more frequent.
The need for a different approach has become clear. The Willis Research Network (WRN) member organization the National Center for Atmospheric Research (NCAR) in the US facilitates the newly established Engineering for Climate Extreme Partnership (ECEP), a synergistic initiative that aims to be “an interdisciplinary collaboration bringing together engineering, scientific, cultural, business and governmental expertise to develop robust, well-communicated predictions and advice on weather and climate extremes in support of society.” This partnership plans to provide a platform for key tools for the public and private sectors to improve their quantification of risk in support of building resilience concentrating on extremes of weather and climate.
A core focus of ECEP is the concept of ‘graceful failure’. Catastrophic failures are normally associated with rigid structures, complex systems or tightly interconnected dependencies. Conversely, a graceful failure emphasises allowing for adaptability and improvisation in an emergency, such as flexible structures, non-complex systems, or loosely interconnected networks of dependence.
In real terms, Hurricane Katrina may be considered an ungraceful failure as exemplified by the breaching of the levees protecting New Orleans which were designed for a potential category 3 hurricane, and even though Katrina was category 3 at the coast, it was a large and intense category 5 storm (highest on the Saffir-Simpson Scale of hurricane intensity) shortly before. This highlights the point that a storm’s category doesn’t tell the whole story.
Katrina’s large size combined with the local bathymetric structure and long-term loss of wetlands led to a 30 foot storm surge as the storm approached the coast. This huge mass of water, combined with insufficient evacuation procedures and the failure of levees and critical pumping systems, led to catastrophic consequences.
Graceful failure encourages consideration of all such events in the chain, and the consequences of each and all together in identifying the impacts of a catastrophe. In the same region, a real-world example of graceful failure might be the 2011 Mississippi floods where 31 floodgate bays of the Morganza Spillway were opened to divert potential flood waters, preventing a major flooding event for Baton Rouge and New Orleans.
Multidimensional hazards, changing societal exposure and unseen vulnerabilities can combine to bring about disasters which will only prioritise ever-increasing need for resilient planning and adaptation to extremes of weather and climate.
Tools in Action
To help the risk community adapt, the ECEP will develop and host the Global Risk, Resilience and Impacts Toolbox,which aims to provide a framework for applications, developed through the partners and collaborations in the group, designed to provide both private and public users with the ability to develop resilient risk management structures.
The Cyclone Damage Potential Index developed at NCAR, and with the WRN, is an example tool for determining the impact potential of a hurricane as it approaches the coastline as it combines intensity (maximum wind speed, traditionally the main factor used to describe hurricane strength), size (area of damaging winds), and translation speed (how fast the storm is moving) into one index. This index can better explain the relationship between measurable hurricane characteristics and damage than using intensity alone. The link between this index and insurance losses is the next step and work is underway at Willis to apply this index in tropical cyclone prone territories around the world.
For the large-scale insurance and reinsurance world, catastrophe modelling has continued to increasingly play an important part in understanding portfolio risk. Techniques are becoming more sophisticated and as data availability and scientific application improves, the ability for analytics to inform decision making in risk management will only grow in the future.
Since Katrina, the market has also changed with a trend toward new ways to find alternative capital, such as insurance-linked securities, insurance side-cars, and cat bonds. These novel financial mechanisms are signs of the insurance world adapting to a new understanding of risk, building financial processes that are agnostic of market conditions. Compound these financial instruments with the scientific endeavour of such collaborations as the ECEP and the WRN, and we can continue to enhance societal resilience through informing government policy and industry regulation.