narrow

The coastal squeeze

June 26, 2025 By EarthWise Leave a Comment

Globally, coastal areas are being squeezed between rising seas on one side and human development on the other. The average distance from the high waterline to the first built-up area with human structures or paved roads is less than 400 yards around the world. The narrower a coast, the sooner rising sea levels cause problems.

Narrow coasts have reduced ability to defend against storm surges and other weather events. Construction close to the sea makes coastal areas extra vulnerable. Narrow coasts are also bad news for biodiversity. A study by the Royal Netherlands Institute for Sea Research investigated plant diversity in both the Netherlands and the United States. They found that the wider the coast was, the greater the plant diversity.

In Florida and Georgia, whenever coastal zones reached a couple of kilometers in width, diversity increased rapidly. In the Netherlands, only coastal areas at least 3.8 kilometers wide reached their maximum plant diversity, but such areas are rare. Dutch sand dune areas are typically no more than a kilometer wide, leaving plant diversity at no more than half the possible level.

Limited biodiversity in narrow coastal strips can be somewhat boosted by nature management but would benefit much more by spatial planning. In the Netherlands, a spot called The Sand Motor is where a gigantic amount of sand was deposited off the coast in 2011. Since then, natural forces have spread it along the coast. Such coastal expansion could increase biodiversity. Biodiversity is not a luxury. It makes for a better future for coastal defense, a healthy drinking water supply, and a better human food supply.

**********

Web Links

Coastal squeeze is bad for biodiversity, and for us!

Photo, posted June 21, 2017, courtesy of Mark Bias via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Trouble For The Outer Banks | Earth Wise

August 9, 2022 By EarthWise Leave a Comment

The Outer Banks are a series of barrier islands off the coast of North Carolina that separate the Atlantic Ocean from the mainland. They are a very popular tourist destination featuring open-sea beaches, state parks, shipwreck diving sites, and historic locations such as Roanoke Island, the site of England’s first settlement in the New World. There is also Kitty Hawk, the site of the Wright Brothers’ first flights.

The ribbon of islands is nearly 200 miles long. Some of them are low and narrow and are only a few feet above sea level. Many are especially vulnerable to Nor’easters in the winter and hurricanes in the summer. The collision of warm Gulf Stream waters and the colder Labrador current helps to create dangerous shoals and some of the largest waves on the East Coast.

Over the years, developers have added billions of dollars’ worth of real estate to the Outer Banks. Rising sea levels and increasingly frequent storms threaten the barrier islands of the Outer Banks. Beach-front cottages have tumbled into the ocean for as long as people have built them in the Outer Banks but now they are falling at a greater rate and more and more are in danger.

The Department of Transportation has spent nearly $100 million dollars to keep NC12, the highway connecting the string of islands, open to traffic. Three new bridges built to traverse inlets opened by storms and bypassing rapidly eroding shorelines raised the cost by another half a billion dollars.

There are many other measures such as pumping sand into eroded areas going on in the Outer Banks, but ultimately, all of the measures may not be enough to deal with rising sea levels and more powerful storms.

**********

Web Links

Shifting Sands: Carolina’s Outer Banks Face a Precarious Future

Photo, posted August 31, 2011, courtesy of NCDOT Communications via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Coffee From Global Warming | Earth Wise

June 16, 2021 By EarthWise Leave a Comment

The global coffee market is valued at over $450 billion a year and supports the economies of several tropical countries. About 100 million farmers depend upon coffee for their livelihoods.

Coffee bushes grow best in a narrow range of temperatures. The existing coffee market is dominated by two species Coffea arabica and Coffea canephora, the latter commonly called robusta. Arabica, the most preferred coffee, thrives in average temperatures between 64 and 72 degrees Fahrenheit. Robusta does not flourish above 75 degrees. Therefore, the warming climate is making growing coffee increasingly difficult.

There are actually well over 100 species of coffee. Many of them grow in warmer places than those preferred by robusta and arabica, but are considered to have poorer flavors, smaller beans, and lower yields.

Researchers at the Royal Botanic Gardens in Britain came across a paper written in 1834 about a species of coffee from the lowland hills of Sierra Leone called Coffea stenophylla. According to the paper, stenophylla supposedly has a flavor superior to arabica’s.

It turns out that stenophylla still grows in parts of Africa with temperature ranges between 75 and 80 degrees. It was actually farmed until the 1920s but was abandoned because robusta was found to have higher yields.

Extensive taste testing verified the positive attributes of stenophylla. Whether it should be cultivated directly tolerating potential yield issues or crossbred with existing commercial coffees remains to be determined. But the prospects for finding more heat tolerant coffees should be encouraging news for coffee addicts.

**********

Web Links

How to save coffee from global warming

Photo, posted October 30, 2012, courtesy of Coffee Management Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.