natural forces

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.

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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

Self-healing concrete

June 25, 2025 By EarthWise Leave a Comment

Concrete is the most widely used building material on Earth. It has a dangerous and costly flaw: it cracks easily. Cracks in concrete can lead to inconvenient damage or to catastrophic structural failures such as collapses of buildings, bridges, or highways.

Concrete is made by mixing crushed stone and sand with powdered clay and limestone and adding water. The mixture hardens and once set becomes extremely strong. However, natural forces like freeze-thaw cycles, drying shrinkage, and heavy loads can cause cracks. Even very tiny cracks can allow liquids and gases to seep into embedded steel reinforcements causing corrosion and weakness.

For over 30 years, researchers have investigated microbe-mediated self-healing concrete. It involves introducing microbial healing agents into cracks and injecting nutrients for the healing agents to produce repair materials. It is not a very practical solution.

Researchers at Texas A&M University have developed a technique inspired by the behavior of lichen systems. Their system, like lichen, uses a combination of cyanobacteria which turns air and sunlight into food, and filamentous fungi, which produces minerals that seal the cracks.

In lab tests, the paired microbes were able to grow and produce crack-filling minerals even in challenging environments such as concrete. If it is possible to produce concrete that can heal itself, it would significantly reduce maintenance costs, extend its longevity, and even protect lives through increased safety.

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Cracking the Code: Deciphering How Concrete Can Heal Itself

Photo, posted May 21, 2009, courtesy of DesignMag via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A surprising drop in renewable power

March 28, 2024 By EarthWise Leave a Comment

Renewable power – which includes wind farms, solar farms, and hydroelectric dams – constitutes over 21% of the country’s utility-scale electricity generation, behind only natural gas power plants at 43%. Nuclear power provides nearly 19% of our electricity and coal, which is gradually diminishing, is at 16%.

Both solar and wind power capacity have been growing rapidly in recent years and will be providing an increasing percentage of our electricity. That being said, it turns out that utility-scale renewable electricity generation actually decreased slightly in 2023 as a result of weather-related issues.

Utility-scale renewables generated about 894,000 gigawatt hours of energy last year, which was 0.8% less than the record amount generated in 2022.

The reasons? The biggest factor was slower wind speeds in the Midwest during the warmer weather months. In 2023, there were fewer warm fronts and cold fronts passing through the region. The passage of fronts is often associated with wind and precipitation.

The other factor affecting renewable generation was a 5.9% drop in hydropower in 2023. The main reason for the decrease was a drop in water levels at many hydroelectric dams in areas experiencing drought.

Experts explain that there is no reason to overreact to a one-year blip in renewables generation. All three major sources of power – sun, wind, and hydroelectric – are tied to natural forces and all of them fluctuate over time. Putting aside minor variations year-over-year, renewable electricity is on pace to more than double by the end of this decade.

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Federal Data Reveals a Surprising Drop in Renewable Power in 2023, as Slow Winds and Drought Took a Toll

Photo, posted July 5, 2014, courtesy of Patrick Finnegan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Paying To Combat Climate Change | Earth Wise

November 2, 2020 By EarthWise Leave a Comment

The majority of Americans believe that climate change is happening, that human activities are largely responsible, and are actually willing to put up their own money to help fight it. Unfortunately, these views diverge sharply along party lines and, as in many other areas these days, the will of the overall majority has little influence on policy.

According to Yale University research, 73% of adults think that global warming in happening and 57% think it is mostly caused by human activities. Furthermore, only 32% believe it is due to natural forces.

A survey conducted in the U.S. in August found that more than two-thirds of Americans – actually 70% – indicated willingness to donate a percentage of their personal income to support the fight against climate change.

Breaking that down further, 28% were willing to provide less than 1% of their income, 33% were willing to contribute 1-5% of their income, 6% said they would give 6-10% of their income, and 3% said they would contribute more than 10% of their income. On the other hand, roughly 30% indicated that they were unwilling to contribute.

The survey also looked at opinions on how the fight against climate change should be paid for. The majority (59%) chose government incentives for both businesses and consumers. Three other options each favored by over 40% of those surveyed were taxes, conservation programs, and business investments.

Another finding of the survey was that 44% are dissatisfied with the job that the federal and state governments are doing to address climate change, 35% are somewhat satisfied, and only 21% are very or completely satisfied with the government’s role.

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Yale Climate Opinion Maps 2020

Two-thirds of Americans are willing to donate part of their income to fight climate change

Photo, posted April 29, 2017, courtesy of majunznk via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.