The Confusion About the Climate Change Challenge

The political battles around climate change often obscure real issues and misdirect resources from higher probability risks to lower probability ones.

To avoid this, we must keep in mind the following points:

? The effects of extreme short-term weather events like hurricanes, torrential rains, heavy winds and mudslides are combinations of the violent effects of weather events and deficiencies in human infrastructure and behavioral responses to the events.?

? The causes of "sea level rise," with which I deal as both a President of a condominium association located on the Gulf of Mexico in Naples, FL and a member of a Board of an association of 80+ coastal condominium associations, are a combination of gradual sea level rise and land subsidence. Solutions must address both natural sea level rise and natural and human factors that cause the land subsidence to worsen.

? Predicting future temperature increases and their effects on glaciers, rainfall levels, drought frequency and duration, and ocean currents has proven to be far more complicated than the scientists have believed. There are links among greenhouse gas emissions, global temperatures, and sea level rise, but the effects are not as linear as media and political figures pronounce them to be. Temperatures are warming and sea levels are rising, and have been doing so for most of the last 200+ years, but modeling has to improve because there are so many different inputs.

For example, climate scientists would agree that the most complicated input to any modeling is the effect of clouds. Depending on where they are located in the atmosphere, they can either warm or cool the earth. Over time, the modeling should improve, but more needs to be learned.

? Storm surges in particular coastal areas depend heavily on the direction and location of how a hurricane makes landfall. They accompany virtually every hurricane where the hurricanes make landfall, but their effect is highly dependent on the convergence of a number of factors. That convergence in a particular location is unlikely to be repeated in any period of years. This write-up from the National Oceanic and Atmospheric Administration does an excellent job identifying the multiple factors that must occur concurrently to produce the kind of storm surge that Hurricane Ian produced in Collier and Lee Counties in Florida.

chrome-extension://nlaealbpbmpioeidemdfedkfmglobidl/https://www.nhc.noaa.gov/surge/surge_intro.pdf

? Heavy sub-tropical storm rains can create as much, if not more, flooding than a Category 4 hurricane that approaches a coastal area from the land side of the coast. We should be addressing all compound flooding events, not just those which result from major hurricanes.

The Multiple Human Inputs to "Natural" Disasters

The storm with the highest death toll in American history was the 1901 Galveston hurricane and tidal storm. Over 6,000 people died. The National Weather Service ignored warnings from Cuban meteorologists and did not order the city evacuated. Had the population been evacuated, the death toll would have been far lower.

Hurricane Sandy did horrific damage because it hit heavily-populated urban and suburban areas and because the transportation, power grid, water, and communications infrastructures were inadequately maintained and repaired. Even today, the New York and New Jersey governments have yet to repair the two transit tunnels under the Hudson River severely damaged by saltwater flooding in these tunnels from Hurricane Sandy. The MetroNorth control system infrastructure was in a basement in Lower Manhattan, rather than on an upper floor out of harm's way, because lower value square foot space was employed for equipment storage.

In Naples, FL, the first two feet of water accumulation in our garage occurred because of water gushing from two storm drains unable to handle the flooding from the rains falling in advance of the Gulf of Mexico storm surge. The storm drain system was known to be inadequate for even ordinary flooding events before Hurricane Ian. Collier County FL's permanent population has increased from 10,000 in 1969 to nearly 400,000 today, but the storm drainage system has not kept pace with population growth. Homes are bigger and more land surfaces are impermeable. Storm water had nowhere to go and made flooding worse. Storm surge effects were also worsened because the hurricane made landfall at high tide, which likely added two feet to its height and impact.

Many buildings and freestanding street posts are prepared to withstand Category 5 hurricane force winds here in Florida. But little, if anything, has been done to address the more frequent and insidious problem, compound flooding.

We have two related, but distinct, problems:

? Inadequately designed and poorly maintained infrastructure; and

? Inadequate focus on the more frequent flooding problem in terms of regulations and building code permits.

Poor storm drainage has another harmful effect: it results in contaminants that should be flowing into waste treatment plants; instead, they surge on to surfaces on which humans and their pets walk. There is too little media coverage about the cost and difficulty of decontaminating a surface that has experienced storm drain back-up are effects.

Sea level rise

Many factors can cause land subsidence. Louisiana's sea level rise relative to its land mass at a rate of 3 feet per century results from a combination of oil exploration and subsurface water extraction causing higher-than-normal land subsidence. A study published recently in the journal Earth's Future attributes a higher-than-normal relative sea level rise in New York City to excessive concentration of tall, heavy buildings, especially near its coastlines.

Challenges of predicting the effects of climate change

While we know that the earth's temperatures are warming and that heavy rainfalls, droughts, and heat waves seem to be of longer duration, meteorologists are unable to identify why certain kinds of weather patterns causing these events are happening.

In one way or another, heavy rains, droughts, and heat waves result from stalled weather systems. Rains last longer because of stalled frontal systems. Droughts and heat waves result from stalled high pressure systems. Alterations in the jet streams affect all these events, but meteorologists are exploring multiple theories as to why these alterations happen. These more frequently occurring events are forms of climate change, but meteorologists have not been successful in discerning their root causes.

Storm surges

When we see heavy flooding and storm surges on news reporting relative to hurricanes, we tend to believe that they occur frequently. Every year, hurricanes make landfall and produce storm surges somewhere in the continental US or on Caribbean Islands. Their visual impacts are breathtaking and frightening.

But the frequency with which they occur in any given location varies considerably. Collier County, FL has had two significant storm surges in the last 250 years, resulting from Hurricane Donna in 1960 and Hurricane Ian in 2022. The Florida Panhandle area has experienced more frequent storm surges, but the likelihood of a surge in any given year in a particular location is very low.

Sea level rise makes storm surges worse by adding one foot higher surge than would have been the case a century ago, but, by itself, it does not create storm surges. Hurricane Ian's storm surge was made worse by 2 feet by making landfall at high tide. When a storm surge occurs, Collier County FL's surges are worse because of the gradual sloping of the Gulf of Mexico toward its coast, but these natural factors are not occurring with any greater frequency because of climate changes.

As a condo association President, we are taking a prudent course in protecting against a future storm surge, whenever it might occur, by planning to relocate our electrical switchgear from our building's basement to a new structure at a level slightly above the first floor. We have also raised our back-up generator pedestal two feet higher to protect it from a future surge. As condo associations, apartment buildings, and single family homes rebuild, they should be doing the same thing with vital infrastructure.

Recognizing that heavy rainfall can occur in many non-hurricane situations

We have lived in the same Darien CT homeowners association since 1994. We have experienced multiple hurricanes, including Hurricane Sandy, and multiple Nor'easters and tropical storms. Our association experienced serious property damage only once and it occurred from a heavy, continuous rainfall during which winds not only did not reach hurricane force levels, but did not reach tropical storm velocities.

This storm occurred in March, 2010. Five large trees toppled over. Two of them crashed on to the roof of one home. One completely blocked our primary way out of the association until a tree removal crew arrived 36 hours later. This "no-name" storm occurred after the ground had been saturated with several inches of rain over the several week period before the storm. The rain was heavy and last 16 hours before it stopped.

We need to understand that heavy rainfall events will occur far more frequently than major hurricanes, especially in Florida, and that the combination of heavy rains, poor storm drainage, and fewer places for water to drain will result in horrific compound flooding. In fact, heavy rainfall events will occur in many more parts of the country in which they have not occurred previously. Although 2020 saw a drop in the percentage of US land area with a disproportionate level of heavy rainfall events, the long term trend over the last 100 years has been upward.

Policy Implications

Reducing the use of fossil fuels, especially through phasing out internal combustion engines, has many societal benefits. Electric or hybrid vehicles produce fewer or no harmful air emissions and they reduce noise pollution significantly. With reduced air emissions, fewer people experience asthma and other respiratory disorders. Regenerative agriculture as a way of reducing greenhouse gas emissions reduces soil erosion and water pollution and results in the production of more nutritious food.

But reducing greenhouse gas emissions will not significantly alter coastal weather or climate patterns or the harmful effects of heavy rains and flooding in the short or medium term. We have to take other actions to deal with flooding, including:

• Changing building codes to discourage the replacement of smaller homes with larger ones that increase impermeable land surfaces. Homeowners who want larger living spaces should build up, not out;
• Communities should take advantage of new technologies to replace impermeable road and sidewalk surfaces with permeable versions of these surfaces to increase storm water drainage. There are many maintenance issues with permeable pavements, but, when properly maintained, they significantly reduce flooding risk.

• Investing in significant enhancements to our storm drainage systems. The St. Louis District of the Army Corps of Engineers just announced a partnership with the city of Wood River, IL to improve the storm drainage system in that city.

• Preventing excessive extraction of water and excessive oil exploration near coastal areas. In addition to overuse of shallow aquifers near a coastline causing land subsidence, salt water from the sea can introduce potentially contaminated water into a public water supply.
• Reducing building weight and height in highly congested urban areas, especially when buildings are constructed on landfill. New technologies can achieve the same strength for concrete while introducing air into the mix that reduces weight by as much as 35%

https://www.architectmagazine.com/technology/using-air-to-reduce-the-weight-and-amount-of-concrete-used-in-construction_o

In Collier County, FL, we are dealing with a joint effort by the Army Corps of Engineers and Collier County to explore the construction of a combination of hardened beach barriers and hardened berms to protect against the next storm surge event. In the opinion of many well-informed experts, this is a suboptimal allocation of public resources. Storm surges occur infrequently, but compound flooding will occur more often and it will be worsened by inadequate storm drainage. Nature-based solutions to reduce the impact of heavy waves are better ways to reduce the force of storm surges.

Moreover, flooding is a nationwide issue, not just a Florida or CT issue. The capacity of storm drainage systems has not kept pace with the stress placed on them. When we build bigger homes that cover more previously green land that once absorbed water with impermeable surfaces, we are inviting more compound flooding events.

Compound flooding is the climate change event with which we should be most concerned.