Rebuild and Forget? New Climate Models Say Not So Fast

In March of this year, I wrote a blog post on the adaptation gap.  Here I discuss that due to some

Climate – Galveston, Texas, September 17, 2008 – Piles of debris are lined up along the seawall on Galveston Island where Hurricane Ike made landfall.

uncertainty as to actual intensity and frequency of future climate-induced extreme weather events, it is very difficult for cities to plan and invest in resilient infrastructure. The outcome of this uncertainty is that cities are not taking the appropriate action to mitigate risk. Business-as-usual continues, the same infrastructure is designed and built and communities remain vulnerable.

To remedy this climate adaptation gap requires better information on the likelihood and intensity of extreme weather events. If this information is unknown, we cannot quantify the risk. When you are not able to quantify the risk, you cannot properly run cost/benefit analysis that would result in more resilient infrastructure. The metric is not there.

New Climate Analysis Points to More Storms

Fortunately, a major step forward was taken this week. Kerry Emanuel from the MIT Lorenz Center published a paper that is likely to shake up the climate adaptation planning industry. The paper “Assessing the present and future probability of Hurricane Harvey’s rainfall” provides greater clarity regarding the likelihood of future major hurricane rainfall events in Texas. The model provides a more concise look at future hurricane risks by assigning probabilities to the likelihood of these events out to the year 2100. They accomplish this by combining global climate models with their own hurricane simulation model. By doing so they are able to develop higher resolution models that can give “precise simulations of hurricanes.” (Read the paper if you want to get more specific.)

From this paper, we see that the likelihood of 20 inches plus rainfall from hurricanes has increased six-fold since 2000.  The likelihood of greater number and intensity will continue to increase out to the year 2100 if we do not work to significantly reduce greenhouse gas emissions.  To state it in another way, the study finds that during the years 1981 to 2000, there was about a 1 in 100 chance of a hurricane producing a large rain event exceeding 20 inches. By the year 2081, the study’s models suggest that the likelihood will increase to a 1 in 5.5 chance.

The benefit to planners and government decision makers is they now have a little better clarity as to what to anticipate in the next few decades. This clarity, i.e. probability distributions and likelihood estimates of future hurricane events, increases their ability to quantify the risk of future hurricane events. What it does not do is help to understand the risks of other natural disasters, such as non-hurricane related floods, droughts and extreme heat in the Texas Gulf Coast region. The problem with this is that we cannot weigh the likelihood and impact of separate extreme climate and weather-related events. How does a community prioritize action if it does not know what is the greatest risk?

Investing in Houston 

Let’s set that concern aside for now because with this study we at least have a better idea as to hurricane risk. So how does this become a part of the decision maker and planners’ conversation and analysis? Is Mayor Turner, Judge Emmett, Harris County Flood Control and/or the Army Corp of Engineers going to use this information to guide future stormwater management infrastructure planning? At this time, they are actively working toward identifying appropriate stormwater mitigation investments. In the policy-making world, we would call this a  punctuated equilibrium agenda-setting event. Now that this is on the public’s agenda, how far will they go and will this momentum continue? Time will tell. With the lack of funding coming from the federal government at this time and the considerable pushback on the $61 billion Texas Harvey Recovery Plan, building more resilient appears not to be a federal priority.

If the federal funding does not materialize, believe it or not, it will be very likely that much of this momentum goes away. People will rebuild, some infrastructure will be patched up and things will continue as usual. If history is any indicator, our short-term memories will allow us to forget and continue on.

It is up to the business and NGO community to keep this a part of our conversation and on the agenda. To keep it on the agenda will require resources, as well as ongoing demand from the private sector, particularly the oil and gas companies. It is in their best interest to do so. Their business and employees can only undergo so many disruptions before employees and their families look for higher ground.

If the private sector decides it is not worth the effort to change the way we do things, we will go back to business as usual. We will rebuild and try to forget this ever happened. However, with what Emanuel’s models are showing, we may not have the luxury of rebuilding and forgetting.





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