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Triple La Niña | Earth Wise

January 16, 2023 By EarthWise Leave a Comment

La Niña is an oceanic phenomenon consisting of cooler than normal sea-surface temperatures in the central and eastern tropic Pacific. It is essentially the opposite of the better-known El Niño. These sea-surface phenomena affect weather across the globe. As one oceanographer put it: when the Pacific speaks, the whole world listens.

There is currently a La Niña underway, and it is the third consecutive northern hemisphere winter that has had one. This so-called triple-dip event is rather rare. The only other times they have been recorded over the past 70 years were in 1954-56, 1973-76, and 1998-2001.

La Niñas appear when strong easterly trade winds increase the upwelling of cooler water from the depths of the eastern tropical Pacific Ocean near the equator. This causes large-scale cooling of the ocean surface. The cooler ocean surface modifies the moisture content of the atmosphere across the Pacific and can cause shifts in the path of jet streams that intensifies rainfall in some places and causes droughts in others.

These weather effects tend to include floods in northern Australia, Indonesia, and southeast Asia and, in contrast, drought in the American southwest. In North America, cooler and stormier conditions often occur across the Pacific Northwest while the weather becomes warmer across the southern US and northern Mexico.

In the spring, the tropic Pacific essentially resets itself and starts building toward whatever condition will happen in the following winter, be it another La Niña or possibly an El Niño. For the time being, forecasters expect the current La Niña to persist through February.

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La Niña Times Three

Photo, posted March 10, 2007, courtesy of Gail via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Environmental DNA | Earth Wise

August 5, 2022 By EarthWise Leave a Comment

Marine protected areas are sections of the ocean where governments place limits on human activity. They are intended to provide long-term protection to important marine and coastal ecosystems. MPAs are important because they can protect depleted, threatened, rare, and endangered species and populations.

In January 2020, the Republic of Palau in the western Pacific Ocean created one of the world’s largest marine protected areas. The Palau National Marine Sanctuary covers 80% of the country’s economic zone and prohibits all extractive activity like fishing and mining over a 183,000 square mile area in order for the island nation to ensure its food security and grow its economy in the face of climate change.

The Marine Sanctuary is an ambitious enterprise. The question is how Palau can evaluate whether and how well it is working?

A team of scientists from Stanford University and Palau-based colleagues are making use of Environmental DNA – or eDNA – technology to monitor the large-scale marine protected area. eDNA is the cells, waste, viruses, and microorganisms that plants and animals leave behind. Samples of marine eDNA effectively provide a fingerprint of the organisms that have recently passed through the water in a given area. This gives scientists a way to assess an ecosystem’s biodiversity and keep track of the types of species inhabiting a specific area. Using eDNA, it is possible to keep track of all the organisms that live below the surface and learn about things we can’t even see.

The team has embarked on a program of periodic sampling of the waters off Palau and hope to be able to monitor the results of establishing the Marine Sanctuary.

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eDNA: Bringing biodiversity to the surface

Photo, posted June 12, 2013, courtesy of Gregory Smith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tree Diversity | Earth Wise

March 4, 2022 By EarthWise Leave a Comment

Scientists have estimated that there are more than 8 million species of plants and animals in existence. Amazingly, only about 1.2 million of them have been identified and described so far and most of those are actually insects. Millions of other organisms have yet to be discovered.

One would imagine that most of these unknown species are tiny things that are hard to spot or encounter. But our ignorance of species even applies to trees, which are pretty easy to spot if you encounter them.

A new study involving more than 100 scientists across the globe has produced an estimate of the number of tree species on the Earth. The new global estimate is that there are 73,000 tree species, which is about 14% more than previously thought. Based on a combination of data from two global datasets, the study yielded a total of 64,100 documented tree species worldwide. The researchers then used novel statistical methods to estimate the total number of unique tree species at biome, continental, and global scales, which includes species yet to be discovered and described by scientists. Therefore, the estimate predicts that there are likely to be over 9,000 tree species still to be found.

Roughly 40% of the undiscovered tree species are likely to be in South America, which is the continent with the highest number of rare tree species and the highest number of continentally endemic tree species – meaning those found only on that continent. Hot spots of undiscovered tree species are likely the tropical and subtropical moist forests of the Amazon basin and the Andes-Amazon interface.

Extensive knowledge of tree richness and diversity is key to preserving the stability and functioning of ecosystems.

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Number of Earth’s tree species estimated to be 14% higher than currently known, with some 9,200 species yet to be discovered

Photo, posted November 5, 2017, courtesy of Deensel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Florida’s Starving Manatees | Earth Wise

January 12, 2022 By EarthWise Leave a Comment

Manatees, also called “sea cows”, have been the victims of farm runoff. They have starved to death by the hundreds along Florida’s east coast because algae blooms fed by nitrogen-rich fertilizer runoff are proliferating on the ocean surface and blocking sunlight from reaching seagrass below. Seagrass is the primary source of food for manatees in the winter. As seagrass dies off, so do the manatees.

Over 1,000 manatees have been found dead so far this year. It is estimated that fewer than 8,000 remain in Florida waters. Efforts are underway to restore coastal seagrass in the region as well as clams and oysters, which filter pollutants from water. Unless the water is cleared up, it will be difficult to regrow the seagrass. But the current situation is that manatees are so short on food that they are eating seagrass roots, killing the plants and thwarting efforts to help seagrass recovery.

Given this dire situation, the federal governmental has approved a program of feeding manatees. The starving animals will be fed by hand in Florida, which is a rare wildlife intervention. Conservation agencies tend to favor leaving wild animals to their own foraging and hunting so that they don’t become dependent on human handouts.

During the trial phase of the program, wildlife experts are likely to feed the animals romaine lettuce and cabbage, which is what manatees in captivity eat. The hope is to give the animals enough additional food for them to get through the winter. The trial feeding will begin on private property. It remains illegal for the public to feed manatees.

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Florida to feed starving manatees in rare conservation move

Photo, posted February 21, 2008, courtesy of Keith Ramos/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Safer Ways To Be Blue | Earth Wise

May 5, 2020 By EarthWise Leave a Comment

Creating blue fabric has always been desirable for people. It has never been easy, but the original way to do it – by using indigo from plants – has been around for 6,000 years. Natural indigo is a rare commodity, often referred to as blue gold. In the 19th century, synthetic indigo was developed and ultimately replaced the natural substance.

Synthetic indigo dye is not an environmentally friendly substance. In order to get it to adhere to fabrics, substances called mordants are required. These are commonly made from metals like chromium and aluminum, are generally toxic, and kill off plants exposed to factory wastewater, destroy ecosystems, and poison drinking water. The dye itself is slow to decompose and is bad for the environment.

Recently, an organic chemist in Brazil named Erick Bastos has figured out a new way to produce blue dye using, of all things, a pigment from beets. By extracting the pigment and tweaking its molecular pattern, he has managed to transform the red color of the pigment to a brilliant blue.

Beet roots contain pigments called betalains and just a tiny amount of beetroot juice can render a lot of dye. By mixing these pigments with a couple of ingredients, a chemical reaction occurred, and the color transformed from red, to yellow, then green, and finally blue.

Testing so far on human liver cells, retinal cells, and developing zebrafish has revealed no toxicity. The results suggest that the new dye – dubbed BeetBlue – is safe. Further testing is needed to know if it is truly safe and whether it will last in the wash. Meanwhile, Professor Bastos is not patenting the dye and hopes it will provide a better way to be blue.

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How Do You Make a Less Toxic Blue Dye? Start With Red Beets

Photo, posted November 7, 2005, courtesy of Lain Buchanan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rare Earths From Mining Waste

May 3, 2019 By EarthWise Leave a Comment

The 17 rare earth elements have become important parts of much of modern technology. Despite their name, most of these elements are relatively plentiful in the earth’s crust, but because of their geochemical properties they are typically dispersed and not often found concentrated in minerals. As a result, economically exploitable ore deposits are uncommon. There are no significant sources in the U.S.

Rare earths play important roles in high-performance magnets, electric motors in vehicles, wind turbines, microphones and speakers, and in portable electronics like cell phones. As these applications become ever larger, the need for additional sources of rare earths increases.

Researchers at Idaho National Laboratory and Rutgers University have studied a method for extracting rare-earth elements from mining waste that could greatly increase the world’s supply of these valuable materials.

It turns out that large amounts of rare earths exist in phosphogypsum, a waste product from producing phosphoric acid from phosphate rock. The U.S. alone mined 28 million tons of phosphate rock in 2017. (Phosphoric acid is used in the production of fertilizers and other products).

The researchers estimate that more than a billion tons of phosphogypsum waste sits in piles at storage sites across the U.S. alone. World-wide, about 100,000 tons of rare earth elements per year end up in phosphogypsum waste. This compares to the total current world-wide production of rare earth oxides of 126,000 tons.

The researchers studied methods for extracting the elements from the waste. A method utilizing a common environmental bacterium showed great promise.

There are concerns about residual radioactivity and other environmental issues in dealing with the waste material, but the world’s supply of rare earth elements might become much greater based on this research.

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