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Worried about Sea Level Rise? Look for the Lichens. – Hakai Magazine

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The clock is ticking for many low-lying coastal areas. Sea level is rising faster than at any time in recorded history, promising to radically redraw the map. At a broad scale, we know this to be true. But knowing precisely which plots will be inundated and which will remain dry land is a much more daunting task. That effort may have an ally almost no one would have guessed: one of the smallest and least conspicuous forms of life—lichens.

More than 18,000 species of lichens have been described worldwide. Each is a community made up of one or more species of fungus and an alga or cyanobacteria. This combination has enabled lichens to survive in diverse and often hostile conditions, everything from tropical heat to bitter Antarctic cold.

To scratch out its niche, each species has developed to tolerate different levels of temperature, light, air quality, and other factors. Because of this sensitivity, lichens are already used by scientists to gauge environmental disturbance, such as the influence of logging or nitrogen pollution. Lichens also vary in their salt tolerance. It’s this property, says botanist Roger Rosentreter at Idaho’s Boise State University, that makes them so useful in understanding sea level rise.

“Lichens are a good indicator of site history,” says Rosentreter, who has studied lichens and related species for over 40 years. Specifically, the species of lichens that grow on a coastal site may be an effective indicator of low levels of saltwater intrusion and spray, which can be caused by infrequent flooding or storm events. Since sea levels are continuing to rise, any site that has experienced occasional salt water in the past is likely to see more frequent flooding and storm effects in the future.

Recently, Rosentreter and his wife, fellow Boise State botanist Ann DeBolt, studied the lichen communities of two state parks near West Palm Beach, Florida. One park, on a barrier island, is subject to frequent salt spray and storm flooding, while the other is inland just 500 meters away. The scientists found two surprisingly different lichen communities at each site. By comparing the two, they started building a list of lichen species that can be useful indicators of the long-term or historical presence of salt water.

Left: the powdery medallion lichen is very sensitive to salt but is not a good indicator of whether a site has experienced the first effects of sea level rise. Photo by Vitaly Charny. Right: the ruffled blue jellyskin is also sensitive to salt, but its slow growth makes it a better indicator. Photo by David Bird

It takes more than just salt sensitivity to make a lichen a good indicator of whether a site has experienced the first effects of sea level rise. The lichen’s own life history also comes into play.

Species like the powdery medallion lichen (left photo) can be killed if subjected to too much salt water by a storm or flood. But this lichen’s quick reproduction lets it swiftly recolonize after the sea recedes. Larger species with slower growth and reproduction, and also low salt tolerance, like the ruffled blue jellyskin (right photo), can better tell the saltwater history of a site. These salt-intolerant lichens could not have survived and grown if a saltwater event like storm spray or flooding had occurred at any point during their life. Since some lichen species can live for decades or longer, the record they provide can be both hyperlocal in space and extensive in time.

Of the 48 different lichen species Rosentreter and DeBolt found at their two Florida survey sites, 11 are reliable indicators of salt water’s presence. Seven of the species only like to grow in places with very low saltwater impact, while four are salt tolerant, so finding them growing suggests the site has a moderate history of salt and a higher risk of being affected by rising seas.

In general, they found that the species that best indicate if a site will be relatively safe from sea level rise and saltwater inundation are lichens that are larger and leafier and often light green or blue in color. But lichens can be tricky to identify, and some promising indicator species look quite similar to less useful ones. “You’ve got to be at least an intermediate plant person to figure it out,” says Rosentreter.

“The good thing is, these aren’t just in Florida. They’re in the whole southeast coastal plain,” he says. Reports on iNaturalist, for instance, put the ruffled blue jellyskin all along the US East Coast and beyond.

Borja G. Reguero, an expert in conserving natural defenses against sea level rise at the University of California, Santa Cruz, who was not involved in the research, sees parallels between how coastal communities and lichens handle environmental change. “It makes a lot of sense to find those indicator [species] where the frequency of spray or flood events are over a threshold where some species are not able to live anymore,” he says. “You could say the same thing about humans and coastal infrastructure. You get to a tipping point where specific neighborhoods get flooded so regularly that they don’t get insurance.”

Modern science offers an array of tools to study sea level rise, from satellite data to groundwater and soil sampling. Lichens could be another way to see, at smaller site-specific scales, where the sea is coming next, and just as importantly, where it is not.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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