Are cities ready?
Weather is getting more extreme.
Remember themovie “Moneyball”? The Oakland A’s are struggling, financially and on the baseball field. Then they introduce an innovative system for figuring out which players will improve team performance. Moving away from observations by scouts, the A’s begin to use advanced statistics to value players. With their new insights, the A’s acquire high-impact players for relatively little money. Within a season, they’re at the top of the game and so successful that within a fewyears the rest of the league has reorganized how they value players, too.
“Moneyball” highlights thepower of innovative knowledge systems: creative new sets of tools and practices for collecting, analyzing and applying data to solving problems. All organizations depend on knowledge systems, but it’s not uncommon, over time, for theknowledge they generate to becomes tale and poorly adapted to changing contexts.
As researchers on resilience and sustainability of cities, we’ve found that this unfortunately has become the case for a number of cities. This is already causing problems: Outdated knowledge systems have exacerbated recent disasters and contributed to growing financial losses from extremeweather, which have exceeded $110 billion in the U.S. this year alone.
Discussions around improving resilience and adaptation to extreme events often focuson upgrading infrastructure or building new infrastructure, such as bigger levees or flood walls. But cities also need newways of knowing, evaluating and anticipating risk by updating their information systems.
500-year flood
Consider the use of 100-year or 500-year flood levels to guide urban planning and development. Using this framework, cit- ies hope to prevent small floods while limiting the occurrence of catastrophic flooding.
Yet, the data behind this strategy are rapidly becoming obsolete. Weather statistics ar enow changing in many places. As a result, cities are experiencing repeat 500year floods, sometimes multiple times, in a few decades or less. Yet cities continue to rely almost exclusively on historical data for projecting future risks.
The city of Houston, for example, has experienced a 167 percent increase in the intensity of heavy down pours between 2005 and2014 as compared to 1950and1959. Hurricane Harvey represented Houston’s third 500-year flood to occur in the past three years. Prior to Harvey, Harris County flood control managers down played the need to change their knowledge systems, arguing that the two prior flooding events were isolated events.
New possibilities
Cities need to better anticipate what would happen these extreme weather events. The past few years have seen a growing number of record-breaking storms, droughts and other weather events.
The National Weather Service labeled Hurricane Harvey “unprecedented,” both for the rapidity of its intensification and the record levels of rainfall it dumped on Houston. Hurricane María hit San Juanas the third-strongest storm to make landfall in the U.S., based on air pressure measurements. Its rapid intensification surprised forecasters and presents yet another challenge to climate and weather models.
Record-breaking events like these cannot be understood using statistics grounded on the past frequency of occurrence. Not recognizing the growing risks from extreme weather is dangerous and costly if cities continue to create more buildings that are more expensive in increasingly vulnerable locations.
What’s needed are new and more creative ways to explore possible futures and their potential implications. One approach is to use climate or other predictive models. Such models add important elements to discussions that can’t be gotten from historical data.
For instance, cities can look at projected sea level rise or storm surges and decide whether it makes economic sense to rebuild homes after damaging storms, or whether it’s better to compensate homeowners to move outside the flood zone.
Tomorrow’s storms
Cities also need to upgrade their knowledge systems to anticipate risks in what are often called “design storms.” These are the anticipated future storms that people who design and build individual structures — from buildings to floodwalls— are required to use in their designs as aminimum risk standard.
Cities need to seriously rethink their design storm standards if they are to fully understand and be comfortable with the future risks from extreme weather events to which their businesses and residents are being exposed.
In New Orleans, for example, the U.S. Army Corps of Engineers created a Standard Project Hurricane in 1957 that defined the wind speeds and storm surges that the levees built around the city wouldhave to withstand.
As with most design storms, the Standard Project Hurricane was based on retrospective data of past hurricane frequency and intensity in the century prior to 1957.
In subsequent decades, however, hurricane frequency and intensity changed significantly in the Gulf of Mexico. The Standard Project Hurricane was not updated, and protection infrastructures were not upgraded, contributing to their failure in the face of Hurricane Katrina.
What cities know and howthey think are essential to whether cities can make better decisions. For over a century, cities have broadly approached knowledge about weather risks by collecting and averaging past weather data. Nature is now sending cities a simple message: That strategy won’t work anymore
Clark Miller is a professor at the School for the Future of Innovation in Society at Arizona State University; Thaddeus R. Miller is an assistant professor at the School for the Future of Innovation in Society and The Polytechnic School at Arizona State University; and Tischa Muñoz-Erickson is a research social scientist at the International Institute of Tropical Forestry. This article was originally published on The Conversation.