Climate Change and Future Hurricanes

Climate Change and Future Hurricanes

A living shoreline project was implemented on this bay in Santa Rosa County to try and prevent further erosion. Photo credit: Carrie Stevenson, UF IFAS Extension

We have reached that time of year when the Atlantic starts cranking out storms, and they will continue to roll out as the dog days of summer progress. Over the last decade, many experts have speculated on how climate change and sea level rise might impact hurricanes in the Gulf of Mexico. Two big issues are coastal erosion and flooding from storm surge and rainfall.

Those who live on the water or frequently visit area shorelines have probably noticed coastal erosion. While a natural part of a coastal ecosystem–and often exacerbated by heavy boat traffic–rising seas can also cause erosion. Sea level rise moves water slowly inland and washes away the roots of grasses and trees that once held the shoreline in place. Buildings and roads close to the water are impacted as well, with “sunny day flooding” on the roads and under pilings in many south Florida cities where water has moved in to stay. Large scale beach renourishment projects, living shorelines, and even road relocations (like the one at Ft. Pickens on Pensacola Beach) are all ways that local officials and property owners can respond to rising seas. However, these efforts always come with a big price tag. When that “line in the sand” is drawn beyond government and household budgets, there will come a point when we can no longer support protection of highly vulnerable coastal infrastructure. The closer a building is physically located to the water (whether built there intentionally or reached by rising seas), the greater the likelihood a hurricane will cause flooding damage from dangerous storm surge. Storm surge and heavy flooding cause 75% of the deaths in any given hurricane.

During a recent webinar, the appropriately named Dr. Chris Landsea of the National Hurricane Center answered several frequently asked questions on the impacts of global warming on hurricanes. Some of the predictions are surprising based on assumptions that have been put out in the media. He made a disclaimer that these are his predictions based on years of expertise and data analysis, and not an official proclamation by the National Hurricane Center. Following are a few of the points he made during his talk.

Dr. Chris Landsea of the National Hurricane Center recently met with floodplain managers around the Gulf Coast to discuss hurricanes.

Question: Will hurricanes get stronger based on increased temperatures?

Answer: The world average temperature has gone up 1.5 degrees Fahrenheit in the past 100 years. Based on data and computer modeling from the NOAA Geophysics Lab, typical hurricane wind intensity will increase slightly, by 3%. In this example, a storm with 100 mph average winds would be 103 mph by the end of the 21st century.

Question: Will we experience more tropical storms as the climate changes?

Answer: Dr. Landsea does not expect more tropical storms as the temperature increases. In fact, frequency may drop very slightly. While there may be more heat energy for hurricanes to feed on, the surrounding conditions will make it tougher for a storm to form. Those conditions may be atmospheric or include a vertical wind shear that tears up the storm.

Question: How will global warming affect rainfall during hurricanes?

Answer: Models and recent experience show that rainfall will increase by 10-20% during tropical storms. Global warming increases the amount of moisture in the atmosphere, and a hurricane can recycle this water into a constant loop of rainfall. Hurricane Harvey in Texas was one example of this situation, during which nearly 8 feet of rainfall fell, flooding neighborhoods. One of the aphorisms of climate change is “wet places get wetter, and dry places get drier.”

Dr. Landsea’s full presentation can be found online here, if you are interested in learning more. Keep in mind that these predictions can change based on land use, atmospheric carbon levels, and human practice change. For more on the work UF IFAS is doing on climate, visit this Florida Sea Grant Climate page.

Perennial peanut: a sustainable, low maintenance groundcover

Perennial peanut: a sustainable, low maintenance groundcover

The bright yellow perennial peanut flower is not only pretty, but edible! Photo credit: Carrie Stevenson, UF IFAS Extension

It’s bright yellow, makes its own fertilizer, and tastes like peanut butter. On my morning walks around the track at our office, I have noticed lately that the perennial peanut (Arachis glabrata) is growing lushly, fulfilling its role as a low maintenance groundcover. The plant thrives in hot weather, full sun, and humidity, so we have nearly reached peak growing conditions for this South American native.

Perennial peanut was brought in from Brazil almost 90 years ago as a valuable hay crop and livestock forage. It is still used regularly for these purposes. However, as years of experience have borne out, there are no insect, disease, or unwanted invasive issues with the plant. The lush green groundcover has been used in the past few decades as a popular turfgrass alternative. It is drought and salt tolerant, and can thrive in low-nutrient, sandy soils.

Perennial peanut is a drought-resistant, salt-tolerant, erosion-managing groundcover. Photo credit: Carrie Stevenson, UF IFAS Extension

Its bright yellow blossoms are delicate and almost orchid-like in shape, standing upright on a thin stem. As mentioned earlier, the flower is also edible and has a very light peanut flavor. The foliage, a deep green with compound leaves, lies close to the ground. Its spreading rhizomes serve as an excellent erosion control method, holding even easily washed out sandy soils in place.

Like its more well-known cousin, the perennial peanut is a legume, which means it can “fix” atmospheric nitrogen, transforming it into a form the plant can use. For a homeowner, this means you do not need to add nitrogen fertilizer. If phosphorus levels are naturally high enough in the soil (as is often the case in south Florida), only small amounts potassium-magnesium sulfate may be needed.

Perennial peanut is a great choice in open areas. Photo credit: Carrie Stevenson, UF IFAS Extension

Perennial peanut is best utilized in open spaces without high foot traffic. If you’d like to see it, come out to the Escambia Extension office; there’s a large swath of it between our main building and the demonstration garden near the walking path. If you are interested in planting or maintaining it, check out these documents from UF IFAS Extension or watch this informative video from a colleague!

 

Hurricane Season has arrived

Hurricane Season has arrived

The lineup of 2020 tropical storm names. Tropical storm “Cristobal” is currently headed towards the northern Gulf of Mexico. Photo credit: The Weather Channel

This past March, many people spoke about sensing a sort of free-floating anxiety, waiting for potential disaster to land at their doorstep. The unknowns we faced as COVID-19 cases increased in the United States were not quite like anything we’d previously experienced, although it felt comparable to knowing a hurricane was about to make landfall. After this virus, perhaps, a hurricane seems like a relief—at least we know what to expect and approximately where the most damage will occur. However, big tropical storms carry with them their own set of unpredictable factors like direction and strength at landfall. But the storm-hardiness of our homes, our tree choices, smart evacuation plans—these we can control. Well-thought out precautions can make the difference between getting right back on your feet after a storm and losing almost everything.

Aluminum shutters are one of the many preventative measures Florida homeowners can include in their hurricane preparedness.
Photo: Carrie Stevenson, UF IFAS Extension

No matter how well you have planned for a hurricane, unexpected issues always come up. However, being ready can cut down on the fear and worry.
A few of those preparedness factors include:
* An evacuation plan
* A hurricane kit
* Home wind mitigation techniques
* Tree evaluation
* Wind/flood insurance
I will discuss each of these topics in depth over the next few weeks. Particularly if you are new to the area or never experienced a hurricane, be sure to review good readiness websites, check out these apps, and see which tips might be the most useful to you and your family as we enter the already-active 2020 hurricane season.

Outdoor Ethics

Outdoor Ethics

Baby terns on Pensacola Beach are camouflaged in plain sight on the sand. This coloration protects them from predators but can also make them vulnerable to people walking through nesting areas. Photo credit: UF IFAS Extension

The controversial incident recently in New York between a birdwatcher and a dog owner got me thinking about outdoor ethics. Most of us are familiar with the “leave no trace” principles of “taking only photographs and leaving only footprints.” This concept is vital to keeping our natural places beautiful, clean, and safe. However, there are several other matters of ethics and courtesy one should consider when spending time outdoors.

  1. On our Gulf beaches in the summer, sea turtles and shorebirds are nesting. The presence of this type of wildlife is an integral part of why people want to visit our shores—to see animals they can’t see at home, and to know there’s a place in the world where this natural beauty exists. Bird and turtle eggs are fragile, and the newly hatched young are extremely vulnerable. Signage is up all over, so please observe speed limits, avoid marked nesting areas, and don’t feed or chase birds. Flying away from a perceived predator expends unnecessary energy that birds need to care for young, find food, and avoid other threats.

    When on a multi-use trail, it is important to use common courtesy to prevent accidents. Photo credit: Carrie Stevenson, UF IFAS Extension

  2. On a trail, the rules of thumb are these: hikers yield to equestrians, cyclists yield to all other users, and anyone on a trail should announce themselves when passing another person from behind.
  3. Obey leash laws, and keep your leash short when approaching someone else to prevent unwanted encounters between pets, wildlife, or other people. Keep in mind that some dogs frighten easily and respond aggressively regardless of how well-trained your dog is. In addition, young children or adults with physical limitations can be knocked down by an overly friendly pet.
  4. Keep plenty of space between your group and others when visiting parks and beaches. This not only abides by current health recommendations, but also allows for privacy, quiet, and avoidance of physically disturbing others with a stray ball or Frisbee.

Summer is beautiful in northwest Florida, and we welcome visitors from all over the world. Common courtesy will help make everyone’s experience enjoyable.

Sea Pork: A shoreline oddity

Sea Pork: A shoreline oddity

Sea pork comes in a wide variety of shapes and sizes. Photo credit: Carrie Stevenson, UF IFAS Extension

Recently I was walking the beach, enjoying a sunset and looking around at the shells and other oddities in the wrack line where waves deposit their floating treasures. Something bright green and oblong caught my eye. It was emerald in color, smooth yet fuzzy at the same time, and firm to the touch. At first, I thought it was a sea bean–a collective term for the many species of seeds and fruits that float to our shores from tropical locations in the Caribbean or Central/South America. The bright green definitely seemed like something botanical in nature. However, the vast majority of sea beans have a woody, protective shell similar to our more familiar pecans or acorns.

I remembered a family member asking about finding a mystery chunk of pink mass she found on the beach a few years ago. It resembled a pork chop more than anything else.

A different variety of sea pork that really lives up to its name. Photo credit: Stephanie Stevenson, Duval County Master Gardener

Looking closer and consulting a couple of resources, I realized we had both (most likely!) happened upon one of the oddest and often-questioned finds on our beaches: sea pork. Ranging in color from beige and pale pink to red or green, sea pork is a tunicate (or sea squirt), a member of the Phylum Chordata, home to all the vertebrate and semi-vertebrate animals. While they look and feel more like a cross between invertebrate slugs or sponges, the tunicates are more advanced organisms, possessing a primitive backbone in their larval “tadpole” form. Despite their blob-like appearance, they are more closely related to vertebrate animals than they are to corals or sponges.

The unusual life cycle of the tunicate. Photo credit: University of Washington, used with permission with Florida Master Naturalist program

During their short (just hours-long) larval stage, the tunicate larvae uses its nerve cord (supported by a notochord similar to a vertebrate spine) to communicate with a cerebral vesicle, which works like a brain. Similar to fish, this primitive brain uses an otolith to orient itself in the water, and an eyespot to detect light. These brain-like tools are utilized to locate an appropriate location to settle permanently. Using a sticky substance, the tunicate will attach its head directly to a hard surface (rocks, boats, docks, etc.) and go through a metamorphosis of sorts. The tunicate reabsorbs its tail and starts forming the shape and structure it needs for adulthood.

As an adult, the organism has a barrel shape covered by a tough tunic-like skin (hence “tunicate”). Adult bodies have two siphons, one to bring water in, another to shoot it out (giving them their other nickname, the sea squirt). The water passes through an atrium with organs that allow it to filter feed, trapping plankton and oxygen. The tunicates will spend most of their lives attached to a surface, pumping water in and out as filter feeders. They may be solitary or live in colonies, and vary widely in color and shape, lending variety to those chunks of sea pork found washing up.

I am still awaiting positive identification from an expert on my green find to confirm that it is, indeed, a tunicate and not an unfamiliar plant. Consulting with Extension colleagues, for now we are pretty confidently going with green sea pork. If you have seen one of these before or something resembling sea pork, let us know! It is fascinating to see the variety and unusual shapes and colors.

.