Climate Change, Conservation, Nature, Science

Great Barrier Reef May Be More Resilient Than Once Thought

New research indicates that the Great Barrier Reef may be more resilient than once thought--but that doesn't mean there's no reason for concern.
A sea turtle swims above the Great Barrier Reef. Photo: Shutterstock

New research gives us reason for hope that the Great Barrier Reef is not set up for doom, despite the extensive damage and bleaching of the reef itself.

Scientists at the University of Queensland, the Australian Institute of Marine Science, CSIRO, and the University of Sheffield have recently published a paper with the results of an extensive study in which they found that there are still 100 reefs on the Great Barrier Reef that could help to promote the regional recovery of its ecosystem.

The Great Barrier Reef consists of more than 3,800 individual reefs. These reefs have suffered unprecedented coral bleaching events over the past couple of years. Additionally, the coral-eating crown-of-thorns starfish has also been plaguing the reef system.

The new study shows that there are 100 reefs that fulfill three criteria to promote coral recovery. First, they should lie in cool areas and rarely experience damage from bleaching, thus being able to supply larvae to as many reefs as possible. In addition, reefs should be located in areas of current that can supply coral larvae to as many reefs as possible; and they should not spread the larvae of the crown-of-thorns starfish.

“Finding these 100 reefs is a little like revealing the cardiovascular system of the Great Barrier Reef,” said study author Professor Peter Mumby. “Although the 100 reefs only make up 3 percent of the entire GBR, they have the potential to supply larvae to almost half of the entire ecosystem in a single year.”

“The presence of these well-connected reefs on the Great Barrier Reef means that the whole system of coral reefs possesses a level of resilience that may help it bounce back from disturbances, as the recovery of the damaged locations is supported by the influx of coral larvae from the non-exposed reefs,” said study lead author Dr. Karlo Hock.

Dr. Hock added that this does not mean the Great Barrier Reef corals are safe or in great condition. There is still plenty of reason for concern when it comes to the health of the GBR. “The fact that the study only identified around 100 of these reefs across the entire 2,300-km length of the massive Great Barrier Reef emphasizes the need for both effective local protection of critical locations and reduction of carbon emissions in order to support this majestic ecosystem.”

However, the research also indicates that focusing efforts on these healthy and well-connected reefs, and continual monitoring of those reefs’ health, may be a step toward restoration of the reef. The ecosystem is still vulnerable to the effects of climate change and predation. So, there’s reason for hope, but that optimism must remain guarded until the forces that caused the death of vast swathes of the reef system can be controlled.

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Climate Change, Nature, Science

Global Warming Hiatus? Not So Much

The "global warming hiatus" really wasn't. Read more in this post.
Arctic glaciers. Photo: Shutterstock

New data from the University of Alaska Fairbanks shows that missing Arctic temperature data, not the climate, created the seeming “pause” of global warming from 1998 to 2012.

In fact, the improved datasets the researchers gathered shows that the Arctic warmed six times faster than the global average during the so-called global warming hiatus.

Atmospheric scientist Xiangdong Zhang collaborated with colleagues at Tsinghua University in Beijing and Chinese agencies studying Arctic warming to analyze temperature data collected from buoys in the Arctic Ocean.

“We recalculated the average global temperatures from 1998 to 2012 and found that the rate of global warming had continued to rise at 0.112 degrees C per decade instead of slowing down to 0.05 degrees C per decade as previously thought,” Zhang said.

How did the data lead scientists down the wrong path before?

Most current estimates use global data that represents a long timespan and provides good coverage of a global geographic area. But the Arctic, being so remote, lacks a comprehensive network of instruments to collect accurate temperature data.

To improve the dataset, Zhang’s team relied on temperature data collected from the International Arctic Buoy Program at the University of Washington. For global data, the team used newly corrected sea surface temperatures provided by the National Oceanic and Atmospheric Administration. By doing so, the team was able to re-estimate the average global temperatures during that time with more accurate and representative data.

The global warming hiatus is a hotly debated topic among climate scientists. Some say that an unusually warm El Niño in 1997-1998, followed by an extended period afterward that didn’t have an El Niño may have disrupted global warming.

It was a nice dream, but unfortunately, the new data sets and resulting estimates prove conclusively that global warming did not pause at all. Not only that, but until recently, scientists didn’t consider the Arctic big enough to greatly influence global temperatures.

“The Arctic is remote only in terms of physical distance,” Zhang said. “In terms of science, it’s close to every one of us. It’s a necessary part of the equation and the answer affects us all.”

Environmental Hazards, Science

Scientists Find New Way to Process Radioactive Waste

The question of what to do with radioactive waste may have been solved by a team of Japanese scientists.
The question of what to do with radioactive waste may have been solved by a team of Japanese scientists. Photo: Shutterstock

Ever since the first atomic bomb was exploded during World War II’s Manhattan Project, and ever since the first nuclear power plant opened in Obninsk, Russia, radioactive waste has been accumulating. As the number of nuclear power plants and nuclear weapon plants increased, the question of what to do with all that waste has become one of the biggest issues facing science today.

The primary issue is what to do with radioactive waste after the uranium and plutonium have been recovered from spent nuclear fuel using standard reprocessing methods such as Plutonium Uranium Redox Extraction (PUREX).

Up until now, the most viable option for disposal of nuclear waste has been burying it deep underground. Other solutions such as partitioning and transmuting, which involve separating nuclear fuel into minor actinides such as neptunium, americium, and curium, have proven to be costly and cumbersome because of the need to separate isotopes before they can undergo transmutation. But now, a team of researchers at Tokyo Institute of Technology may have come up with a solution to the radioactive waste problem.

The team discovered a method of dramatically reducing the effective half-life of long-lived fission products (LLFPs) such as selenium-79, zirconium-93, technetium-99, palladium-107, iodine-129, and caesium-135. That method involves transmuting these isotopes in fast-spectrum reactors, which don’t need isotope separation like other methods do.

By adding a moderator (slowing-down material) called Yttrium deuteride (YD2), the team found that LLFP transmutation efficiency increased in the radial blanket and shield regions of the reactor. The researchers say this increased effectiveness is due to the moderator’s ability “to soften the neutron spectrum leaking from the core.”

Using this method, the researchers say, the 17,000 tons of LLFPs in Japan could potentially be disposed of by using 10 fast spectrum reactors. This method also has the advantage of contributing to electricity generation and supporting efforts toward nuclear non-proliferation.

Although ultimately, the best solution to the nuclear waste problem is to invest in non-toxic energy sources like solar and wind power, it’s a good thing these researchers came up with a way to decrease the toxicity of radioactive waste and give its by-products a new life—and a much shorter half-life.

carbon emissions, emissions, Science

Moving Bus Stops Could Reduce Pollution Exposure

Moving bus stops 120 feet from intersections can drastically reduce the amount of pollutants bus commuters are exposed to.
Passengers board an MTA bus in New York. Moving that stop away from the intersection could reduce the pollution to which transit commuters are exposed. Photo: Roman Tiraspolsky / Shutterstock.com

There’s no doubt that mass transit can make a huge difference in the overall air quality of cities. An increasing number of people are realizing that they can reduce their carbon footprint by riding a bus to and from work rather than being stuck in traffic in a car.

There’s just one problem with riding the bus, and that’s waiting for the bus.

Research has shown that in many cities in the United States and internationally, bus riders could spend 15 to 25 minutes each way waiting for a bus. This isn’t just a convenience issue; it’s a pollution exposure issue, too.

“The wait often means spending time in some of the most polluted locations in cities, close to intersections where cars, trucks, and buses are continually stopping and accelerating, spewing out high concentrations of noxious exhaust,” said Suzanne Paulson of UCLA, senior author of an article that appeared recently in the journal Environmental Pollution. “The exhaust contains gases and large amounts of ultrafine particles that are essentially unregulated by the Environmental Protection Agency because the EPA regulates fine particles by weight, and these particles weigh so little.”

The good news, according to the researchers, is that moving bus and light rail stops to locations 120 feet from intersections can significantly reduce the amount of pollutants to which bus commuters are exposed.

The researchers came to their conclusions by using a zero-emission vehicle equipped with instruments that measure ultrafine particles and tailpipe pollutants like carbon monoxide and nitrogen oxide. The studies were conducted in several neighborhoods in and around Los Angeles, over a 15-day period from summer into late fall in 2013 and over four days in the summer of 2014.

“We then combined and analyzed the data for each intersection to create high-resolution maps of pollutant concentrations along blocs,” said study lead author Wonsik Choi.

“Except in areas with minimal traffic, we always found there would be a significant reduction [of pollutants],” said Choi.

Traffic engineers believe that traffic flows better if bus stops are located after intersections rather than before. Better traffic flow can lead to less stop-and-go traffic, which would also improve air quality. The researchers caution that although moving the stops 120 feet from the end of a block will improve transit users’ pollution exposure, as long as that distance doesn’t put the bus stop in range of pollution from the next street.

Considering that most city blocks are about generally about 400 by 400 feet in size, it seems like it should be easy to move bus stops 120 feet away from intersections. That doesn’t mean buses won’t park all along a block where a stop is located, but it does mean that theoretically, passengers waiting for their bus will be able to do so in an area that exposes them to fewer pollutants.

Environmental Hazards, oceans

Keeping Plastic Out of Our Waters

Several nations and states are taking measures to prevent plastic pollution from reaching the oceans.
Plastic pollution in the ocean. Photo: Shutterstock

This past week Chile’s President Michelle Bachelet signed a bill that will ban plastic bags in more than 100 coastal areas. Her decision, she said, was about “taking care of our marine ecosystems.”

“Our fish are dying from plastics ingestion or strangulation; [limiting plastic bags] is a task in which everyone must collaborate,” she added.

It’s a huge deal, not only for Chile’s environment, but for other countries considering their own plastic bag ban.

Chile’s World Wildlife Fund noted that the bill “marks a very important milestone for Chile and opens the door for the whole country to say goodbye to plastic bags.”

According to a 2015 study published in Science, about eight million tons of plastic are dumped into the sea every year, which can affect millions of marine species. And toxins ingested by fish exposed to those plastics can affect humans as well when they eat those fish.

Chile’s potential ban on plastic bags isn’t the first such ban. The U.S. in particular has already instated bans in many areas, including Massachusetts, California, and Washington. They’ve been shown to be quite effective, too: The ban in San Jose, California led to an 89 percent reduction in plastic bags ending up in storm drains. And in Seattle, Washington, the plastic bag ban has led to a 50 percent reduction of plastic bags ending up in city dumps.

In other areas it’s been trickier. State Senator Linda Stewart of Orlando recently announced she will file a bill in Tallahassee to reverse the current law that prevents governments from banning plastic bags and Styrofoam containers.

Why would a city have such a law in place to begin with? Money, it seems: Grocery heavy-hitter Publix lobbied state politicians to the tune of $1 million to get the law against banning plastic bags instated. However, Stewart may be turning the (plastic) tides with her bill, if it’s passed. At the very least, it’s inspired a similar measure in the Florida House of Representatives.

Banning plastic bags in more places—both in the U.S. and elsewhere—is likely to be a huge boon to marine wildlife. But there’s still a lot of work to be done.

Nature, oceans

New Study Says Sea Animals Eat Plastic Because of Its Taste

A new study says that sea animals may like plastic because it tastes good.
These coral polyps are feeding–and most likely ingesting lots of microplastics in the process. Photo: Shutterstock

Scientists have long known that plastic in the oceans can mimic prey, causing huge problems for sea life. But what they didn’t know is that even corals eat plastic.

Corals don’t have eyes, and they don’t move from their location, so why would they eat plastic? Apparently because it tastes good, according to a recent study from Duke University.

This taste factor may also be true for other sea life. After all, anecdotal evidence suggests that our cats and dogs eat plastic because they like the taste and/or the texture, so why wouldn’t sea life have the same reaction?

Microplastics, tiny pieces of weathered plastic less than 5 millimeters in diameter, have been accumulating in the world’s oceans for 40 years or more, and now they’re ubiquitous in the marine environment. They don’t just pose threats to corals, they also pose a threat to foraging sea animals including birds, turtles, mammals, and invertebrates.

Because plastic is largely indigestible, it can lead to intestinal blockages, create a false sense of fullness, or reduce energy reserves in animals that eat it.

“About eight percent of the plastic that coral polyps in our study ingested was still stuck in their guts after 24 hours,” said study co-lead author Austin S. Allen, a Ph.D. student at Duke.

Plastics can also leach hundreds of chemical compounds into the bodies of the creatures that eat it and into the environment as well. The biological effects of most plastic compounds are unknown, but we do know that some have already been shown to cause harm. For example, phthalates are confirmed environmental estrogens and androgens—that is, hormones that affect sex determination.

“Corals in our experiments ate all types of plastics, but preferred unfouled microplastics by a threefold difference over microplastics covered in bacteria,” Allen said.

“When plastic comes from the factory, it has hundreds of chemical additives on it. Any one of these chemicals or a combination of them could be acting as a stimulant that makes plastic appealing to corals,” said Alexander C. Seymour, a GIS analyst at Duke, who co-led the study with Allen.

The researchers hope their findings will encourage more scientists to study the role taste plays in determining why marine animals ingest microplastics.

“Ultimately, the hope is that if we can manufacture plastic so it unintentionally tastes good to these animals, we might also be able to manufacture it so it intentionally tastes bad,” Seymour said. “That could significantly help reduce the threat these microplastics pose.”

Uncategorized

Whales and Dolphins Have “Human-Like” Cultures and Societies

Dolphins and other cetaceans have very complex social culture, and they even have regional dialects.
Dolphins and other cetaceans exhibit sophisticated social behaviors such as alloparenting, the parenting of other parents’ young. Photo via Pixabay

Whales and dolphins are increasingly threatened by fishing activities, environmental noise, and other factors. If we don’t take a stand to conserve these creatures, we could end up wiping out two other species with high intelligence and culture.

A recent study published in Nature Ecology & Evolution shows that cetaceans (whales and dolphins) live in tight-knit social groups, talk to each other, have complex relationships, and even have regional dialects.

The study links the complexity of whales’ and dolphins’ culture with the size of their brains.

Researchers from the University of Manchester in England, the University of British Columbia, the London School of Economics and Political Science, and Stanford University teamed up to create a large dataset of cetacean brain size and social behaviors.

They compiled information on 90 different species of whales, porpoises, and dolphins. What they found was a massive pile of evidence that cetaceans have social and cooperative behavior traits similar to those found in human societies. The study also showed that these characteristics are linked with encephalization—brain size and brain expansion.

Some of the behavioral similarities they found between cetaceans and humans and other primates include:

  • They form complex alliance relationships. That is, they work together for mutual benefit.
  • They teach one another how to hunt and use tools, also known as social transfer of hunting techniques.
  • They hunt cooperatively.
  • They “talk” to one another using a series of complex vocalizations, and even have regional group dialects to their language.
  • They use “name” recognition. That is, they have “signature whistles” unique to individual members of the pod.
  • They work cooperatively with humans and other species.
  • They look after young members of their pods that aren’t their own—a phenomenon known in science as alloparenting.
  • And, of course, they’re well known to enjoy social play.

Manchester University evolutionary biologist Dr. Susanne Shultz said, “We know whales and dolphins…have exceptionally large and anatomically sophisticated brains, and therefore have created a marine-based culture [similar to that of human society]. That means the apparent co-evolution of brains, social structure, and behavioral richness of marine mammals provides a unique and striking parallel to the large brains and hyper-sociality of humans and other primates on land.”

However, Dr. Shultz added, “they won’t ever mimic our great metropolises and technologies because they didn’t evolve opposable thumbs.”

Dr. Kieran Fox, a neuroscientist at Stanford, said, “Cetaceans have many complex social behaviors that are similar to humans and other primates. They, however, have different brain structures from us, leading some researchers to argue that whales and dolphins could not achieve higher cognitive and social skills. I think our research shows that this is clearly not the case. Instead, a new question emerges: how can very diverse patterns of brain structure in very different species nonetheless give rise to highly similar cognitive and social behaviors?”