Tag Archives: Florida

Mangroves and Marshes: A Shield Against Catastrophe?

“We believe that natural ecosystems protect against catastrophic coastal flood losses, but how can we prove it?”

This question was the start of a conversation in 2014 which has led to some interesting results. And it set us thinking: can RMS’ models, like the one which estimates the risk of surge caused by hurricanes, capture the protective effect of those natural ecosystems?

The conversation took place at a meeting on Coastal Defenses organized by the Science for Nature and People Partnership. RMS had been invited by one of our leading clients, Guy Carpenter, to join them. The partnership is organized by The Nature Conservancy, the Wildlife Conservation Society, and the National Center for Ecological Analysis and Synthesis.

We were confident we could help. Not only did we think our models would show how biological systems can limit flood impacts, we reckoned we could measure this and then quantify those benefits for people who calculate risk costs, and set insurance prices.

RMS’ modeling methodology uses a time-stepping simulation, which relies on a specialist ocean atmosphere model, allowing us to evaluate at fine resolution how the coastal landscape can actually reduce the storm surge—and in particular lower the height of waves. In many buildings the real weakness proves to be the vulnerability to wave action rather than just the damage done by the water inundation alone.

The first phase of RMS’ work with The Nature Conservancy is focused on coastal marshes as part of a project supported by a Lloyd’s Tercentenary Research Foundation grant to TNC and UC Santa Cruz. Under the supervision of Paul Wilson, in the RMS model development team, and working with Mike Beck who’s the lead marine scientist for The Nature Conservancy, the project is focused on the coastlines, which were worst impacted by the surge from Superstorm Sandy. The irregular terrain of the marsh and resulting frictional effects reduce the surge height from the storm. Our work is showing that coastal marshes can reduce the flood risk costs of properties, which lie inland of the marshes by something in the range of 10-25%.

Tropical Defenses

So, that’s the effect of coastal marshes. But what about other biological defenses such as mangrove forests and offshore reefs (whether coral or oyster reefs)? Further research is planned in 2016 using RMS models to measure those likely benefits too.

But here’s a rather intriguing (if unscientific) thought: is there a curious Gaia-like principle of self-protection operating here in that the most effective natural coastal protections—mangroves and coral reefs—are themselves restricted to the tropics and subtropics, the very regions where tropical cyclone storm surges pose the greatest threat? Mangroves cannot withstand frosts and therefore in their natural habitat only extend as far north along the Florida peninsula as Cape Canaveral. And yet in our shortsightedness humans have removed those very natural features, which could help protect us.

Paradise Lost?

Between 1943 and 1970 half a million acres of Florida mangroves were cleared to make way for smooth beaches—those beautiful and inviting stretches of pristine sand which have for decades attracted developers to build beachfront properties. Yet, paradoxically, that photogenic “nakedness” of sand and sea may be one of the things, which leaves those properties most exposed to the elements.

With the backing of The Nature Conservancy it seems mangroves are making a comeback. In Miami-Dade County they’re examining a planting program to protect a large water treatment facility. Of course biological systems can only reduce part of the flood risk. They can weaken the destructive storm surge but the water still gets inland. To manage this might require designing buildings with water-resistant walls and floors, or could involve a hybrid of grey (manmade) and green defenses. And if we can reduce the destructive wave action, that might allow us to build earth embankments protected with turf in place of expensive and ugly, but wave-resistant, concrete flood walls.

On March 28, 2015 The Nature Conservancy organized a conference and press briefing in Miami at which they announced their collaboration with RMS to measure the benefits of natural coastal defenses. The coastline of Miami-Dade, already experiencing the effects of rising high tide sea levels, presents real opportunities to test out ways of combatting hurricane hazards and stronger storms through biological systems. Our continued work with The Nature Conservancy is intended to develop metrics that are widely trusted and can eventually be adopted for setting flood insurance prices in the National Flood Insurance Program.

Water, Water Everywhere: The Effect of Climate Change on Florida

Climate change has been a hot topic in Florida for quite some time. Just last week, President Obama visited the Everglades to discuss the need to address climate change now.

RMS partnered with the Risky Business Initiative to quantify and publicize the economic risks the United States faces from the impacts of a changing climate. In Florida, there is a 1% chance that by 2100, 17% of current Florida property value will be underwater, causing a $20.7 billion increase in annual flooding losses, and $681 billion worth of property loss due to sea level rise.

Bob Correll, principal at the Global Environment Technology Foundation leading the Center for Energy and Climate Solutions: Just last week a report commissioned by the G7 was released to the foreign ministers, including Secretary of State John Kerry, titled “A New Climate for Peace: Taking Action on Climate and Fragility Risk.” It outlines seven things we need to worry about as the changing climate becomes more evident, including sea-level rise and coastal degradation.

Brian Soden, atmospheric sciences professor, University of Miami: Sea level rise is the impact of climate change that I’m most worried about. The rate of sea level rise has almost doubled in Miami over the past decade. We are the canary in the coal mine. If you increase sea level by just three feet, which is in the middle of the range of projections, the Everglades would pretty much be gone.

Robert Muir-Wood, chief research officer, RMS: At RMS we attempt to be completely objective about risk. We attempt to take the full scientific understanding and translate it into information about risk and the associated cost. Financial markets are smart. Future risk is already starting to affect the current value of property.

Matthew Nielson, senior director of global governmental and regulatory affairs, RMS: Regulations generally fall into two buckets: curbing emissions so we can temper this problem and thinking about future development and planning to account for future sea level rise.

But what do we do now? There are a lot of things to think about – one is drainage issues. Another is access to fresh water.

Paul Wilson, senior director of model development and lead modeler for the Risky Business Initiative, RMS: It will be interesting to see how things play out – if the response will come as a result of science and gradual sea level rise, or only after a major catastrophe.

Muir-Wood: It’s very hard for communities to take action until they’ve had a disaster. As we’ve seen with Hurricane Katrina and Superstorm Sandy, suddenly there’s all sorts of enlightened thinking about future risk, such as investments in sea defenses. Unfortunately, it often takes a catastrophe to impact on decisions about mitigating risk.

Paul VanderMarck, chief products officer, RMS: You can only build a sea wall so high before it’s not worth living here anymore.

Soden: The biggest question I ask myself is “when do I sell?”

Correll: A year ago the WEF came to us and asked if we would be willing to work with their young global leaders. We had the head of all Shell operations in the Middle East. We had the former head of GE operations in India. They are getting the message. They walked away saying, “we need to rethink our business plans to plan for the future.”

Modeling provides a lot of the underpinnings to make decisions that are outside of the norm. The past is no longer a prologue to the future.