Opinion: Wave of flooding a wake-up call

Andrew D. Gronewold and Richard B. Rood
A Hanover Street resident surveys the damage along Currier Street in Dearborn Heights on Wednesday, May 1, 2019 as Dearborn Heights firefighters rescue a family from their flooded home.

Catastrophic flooding is ravaging coastal and inland communities across the Central Midwestern United States, including Michigan. Images of communities coming together to build barriers using sand bags and putting the pieces back together after experiencing damaging floods are sweeping across the news.

We’ve seen an increase in the frequency and intensity of severe storms, and this trend will likely continue as the effects of climate change become more pronounced. These events serve as warnings that we must better prepare and plan for the future ahead.

The governor of Michigan has already declared a state of emergency for southeastern Michigan in response to the early onset of high-water levels, and in anticipation of further and more widespread flooding across the region. 

Most recently, the United States Army Corps of Engineers released an official forecast confirming that very high-water levels are expected across all of the Great Lakes, with record-high levels expected across Lakes Superior, St. Clair, and Erie. 

The city of Montreal recently issued a state of emergency as well, and they aren’t alone in grappling with these challenges. Water levels in Davenport, Iowa, are higher than they’ve been in over 150 years. Elsewhere along the Mississippi River, waters are approaching or surpassing record levels.

As we look ahead, it is important for residents of Michigan and the United States to have the foundational resources and knowledge to anticipate and respond to these events. It is even more critical that people around the world heed the warning of changes in the distribution of water at a global scale. 

Projected increases in droughts, severe storms, and flooding events, for example, have numerous ill effects, including an amplified risk of erosion, sewage overflow, interference with transportation, and flood damage. Increased storm severity may also have a negative economic impact due to resulting damages and increased costs of preparation, clean up, and business disruption.

In southeastern Africa, millions of people are suffering from the effects of an unprecedented sequence of back-to-back cyclones (Cyclone Idai and Cyclone Kenneth); hundreds have died, and thousands of new cases of malaria and cholera are being reported. 

Cyclone Fani, the strongest storm to hit India in 20 years, brought widespread damage to that region that is still not fully reconciled. 

These events, even in isolation, are astounding. There coincidence warrants careful retrospection and collective action focused on critical guidance questions. 

Is there, for example, a connection or common driver among these unprecedented global meteorological and hydrological events? Are they consistent with what scientists have been predicting as the planet warms? What changes should be made in how humans interact with marine and freshwater coastlines as we rapidly accumulate evidence of changes in the frequency and magnitude of extreme events?

We, all, are embarking on a time of strong and unprecedented climate change. This time of transitory climate will lead to a series of disruptive catastrophes. Floods, related to extremes of precipitation and sea level rise, are among the most certain of these catastrophes. 

If we manage to dramatically reduce carbon dioxide emissions, then, decades from now we might begin to rein in bucking extremes of flood and drought. We cannot, however, avoid them. 

We must take on the challenge of forecasting, planning for, and managing these catastrophes; the strategy of continually relocating, fortifying, and rebuilding as a response is not sustainable.

The warning floods of 2019 are hard-earned case studies that management authorities should use as a basis for future meteorological and hydrological scenarios, and for translating those scenarios into direct human, environmental, and infrastructure impacts at regional and urban scales. 

The set of global catastrophic events over the past month serve not only as warnings, but as a call to action.

Andrew D. Gronewold is associate professor at the University of Michigan School for Environment and Sustainability. Richard B. Rood is professor at the University of Michigan Climate and Space Sciences and Engineering.