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Dire Once-in-a-Century Storms Could Become Annual Events Soon, Scientists Warn

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The best case scenario for the climate crisis is looking increasingly disastrous for much of the world, especially when it comes to rising seas.

Even if we can limit global warming below 2 degrees Celsius, in line with the Paris Climate Accord, by 2100 many coastal regions could be experiencing once-in-a-century sea level threats, such as storm surges, high tides and threatening waves, at least once a year.

 

That’s a 100-fold increase in coastal flooding, and according to new global models, that’s if we’re lucky. If we do nothing to change our behavior, the world could soon blow past 2 degrees Celsius of warming, at which point sea level scenarios will grow significantly worse.

Recent projections for more than 7,000 coastal locations around the world suggest that at 1.5 degrees of warming, at least half of the sites studied will be annually affected by extreme sea level events.

At 2 degrees Celsius of warming, a further 14 percent will experience the same by 2100.

In all likelihood, some locations will suffer these effects even sooner. Under the 1.5 degree scenario, for instance, some coastal locations could experience a 100-fold increase in extreme sea level events by as early as the 2070s.

The authors say this is “overwhelmingly true” for places in the tropics, like Hawaii and the Caribbean, as well as the southern half of North America’s Pacific coast, all of which appear particularly vulnerable to rising seas. As more sea ice melts, parts of the Mediterranean coast and the Arabian Peninsula could also become hotspots for extreme sea level activity. 

 

“The tropics appear more sensitive than the northern high latitudes,” the authors write, “where some locations do not see this frequency change even for the highest global warming levels.”

The results align with recent sea level projections, which suggest we have been seriously underestimating the rise of our oceans at the lower ends of global warming.

Already this year, a study found sea level rise is impacting coastal areas four times faster than we thought. The miscalculations have a lot to do with uncertainties regarding projected sea level rise and how it will shake out the world over – there are a lot of variables to include in the calculations.

The new model seeks to make up for these limitations. It is based on a ‘voting’ system, which helps to balance out various different scenarios of sea level rise and the many uncertainties involved.

For all six scenarios of warming by 2100, researchers took the median values at which sea level events become annual and used these as individual ‘votes’. The ‘majority vote’ was therefore the lowest warming level at which the frequency of storm surges and other sea level events became annual disasters.

 

This democratic system was first applied to data on extreme sea level events from a smaller subset of 179 coastal locations, before being expanded to a larger set of 7,283 locations.

In the end, the authors found a majority vote that agreed 43 percent of all coastal locations studied will experience extreme sea level events on an annual basis, even at the lower end of 1.5 degrees of warming.

What’s more, many of these coastal regions will experience these effects before the end of the century, possibly even as soon as 2070.

At 2 degrees of warming, the majority vote suggests a further 15 percent more coastline will be affected. At 3 degrees of warming, this dire scenario could hit as early as 2060.

Still, that’s just what the majority vote suggests. Some of the more pessimistic data points on each of the six distributions indicate that 99 percent of all locations could experience extreme sea level events at 1.5 degrees of warming.

The findings highlight a “substantial level of disagreement among the six estimates“, which suggests there’s still a whole lot of uncertainty in our models.

 

The most optimistic voting outcome, for instance, suggests only 2 percent of all coastal regions studied will experience extreme sea level events under the same warming scenario. But that optimistic scenario requires a “very strict” unanimous vote across all six estimates that probably wouldn’t happen often.

Once again, the new study highlights we need further research to refine our sea level models to see where the worst effects will strike first. While some parts of North America’s Atlantic coast could be hit by dramatic flooding, the study predicts other nearby regions will remain entirely unaffected.

Why this wild variation occurs in such nearby locations will need to be further analyzed, but it’s something that other researchers have noticed before – an artifact of the scientific difficulties involved in putting firm numbers on sea level rise.

For instance, even in a terrible scenario where global warming reaches past 5 degrees Celsius and ice sheets virtually disappear the world over, the majority vote suggests approximately 20 percent of all the coastal sites studied will remain unaffected by extreme sea level events.

Northern coastal regions like Alaska and northern Europe are those that seem to be most safe from these future disasters.

“Our findings have important policy and practical implications as they highlight that even if the Paris Agreement goals will be achieved, extreme events potentially conducive to coastal flooding will be experienced at unprecedented frequencies in many parts of the world’s coasts,” the authors write.

That’s a big ‘if’.

The study was published in Nature Climate Change.

 

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Indian Coast Guard to get three more pollution control vessels to enhance capabilities

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Panaji: As a marine pollution control response, three more pollution control vessels (PCVs) will be added to the Indian Coast Guard’s (ICG) fleet, Union Defence Secretary Ajay Kumar said on Tuesday.

Speaking to reporters on the sidelines of the 8th National Pollution Response Exercise currently taking place in Goa, Kumar said that India is also willing to help friendly countries in upgrading their capabilities.

Around 19 friendly countries are participating in the exercise.

The Union government is continuously trying to upgrade the ICG’s capabilities to face pollution hazards in the ocean.

“Today, the Indian Coast Guard is capable of handling the highest level of oil spills in this region, which is 700 tonnes and above. Only a few countries in the world have this capability,” Kumar said.

Currently, the ICG has two dedicated vessels for pollution response, while three more will be added to its fleet to enhance its capability, he said.

The Indian Ocean is one of the busiest routes in the world and half of the trade takes place in the region, the senior official said, adding that oil exploration has also increase and accidents can happen anywhere.

Countries are also battling with the issue of plastic waste being dumped in the ocean, he said.

“We need to fight this (plastic pollution) collectively. It cannot be done by one country. All the coastal countries in the region need to make efforts,” Kumar said.

The defence secretary lauded the Punit Sagar Mission launched by Prime Minister Narendra Modi to clear plastic from the coastline.

“We should ensure that plastic waste is not washed into the ocean. Every year, 15,000 million tonnes of plastic washes into the Indian Ocean from different countries. If this continues, our marine life, environment, ecology and health will be affected,” he said.

Asked about cooperation from Pakistan and China over the pollution response, Kumar said, “This is an environmental issue and all countries should contribute towards it.” Several treaties have been signed to reduce pollution in the Indian Ocean, and friendly nations will have to collectively ensure that these are observed, he said.(GoaNewsHub)

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Brain Implant Translates Paralyzed Man’s Thoughts Into Text With 94% Accuracy

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A man paralyzed from the neck down due to a spinal cord injury he sustained in 2007 has shown he can communicate his thoughts, thanks to a brain implant system that translates his imagined handwriting into actual text.

 

The device – part of a longstanding research collaboration called BrainGate – is a brain-computer interface (BCI), that uses artificial intelligence (AI) to interpret signals of neural activity generated during handwriting.

In this case, the man – called T5 in the study, and who was 65 years of age at the time of the research – wasn’t doing any actual writing, as his hand, along with all his limbs, had been paralyzed for several years.

But during the experiment, reported in Nature earlier in the year, the man concentrated as if he were writing – effectively, thinking about making the letters with an imaginary pen and paper.

As he did this, electrodes implanted in his motor cortex recorded signals of his brain activity, which were then interpreted by algorithms running on an external computer, decoding T5’s imaginary pen trajectories, which mentally traced the 26 letters of the alphabet and some basic punctuation marks.

“This new system uses both the rich neural activity recorded by intracortical electrodes and the power of language models that, when applied to the neurally decoded letters, can create rapid and accurate text,” says first author of the study Frank Willett, a neural prosthetics researcher from Stanford University.

 

Similar systems developed as part of the BrainGate have been transcribing neural activity into text for several years, but many previous interfaces have focused on different cerebral metaphors for denoting which characters to write – such as point-and-click typing with a computer cursor controlled by the mind.

It wasn’t known, however, how well the neural representations of handwriting – a more rapid and dexterous motor skill – might be retained in the brain, nor how well they might be leveraged to communicate with a brain-computer interface, or BCI.

Here, T5 showed just how much promise a virtual handwriting system could offer for people who have lost virtually all independent physical movement.

BrainImpantDevice2A diagram of how the system works. (F. Willett et al., Nature, 2021, Erika Woodrum)

In tests, the man was able to achieve writing speeds of 90 characters per minute (about 18 words per minute), with approximately 94 percent accuracy (and up to 99 percent accuracy with autocorrect enabled).

Not only is that rate significantly faster than previous BCI experiments (using things like virtual keyboards), but it’s almost on par with the typing speed of smartphone users in the man’s age group – which is about 115 characters or 23 words per minute, the researchers say.

 

“We’ve learned that the brain retains its ability to prescribe fine movements a full decade after the body has lost its ability to execute those movements,” Willett says.

“And we’ve learned that complicated intended motions involving changing speeds and curved trajectories, like handwriting, can be interpreted more easily and more rapidly by the artificial-intelligence algorithms we’re using than can simpler intended motions like moving a cursor in a straight path at a steady speed.”

Basically, the researchers say that alphabetical letters are very different from one another in shape, so the AI can decode the user’s intention more rapidly as the characters are drawn, compared to other BCI systems that don’t make use of dozens of different inputs in the same way.

BrainImpantDevice2The man’s imagined handwriting, as interpreted by the system. (Frank Willett)

Despite the potential of this first-of-its-kind technology, the researchers emphasize that the current system is only a proof of concept so far, having only been shown to work with one participant, so it’s definitely not a complete, clinically viable product as yet.

The next steps in the research could include training other people to use the interface, expanding the character set to include more symbols (such as capital letters), refining the sensitivity of the system, and adding more sophisticated editing tools for the user.

There’s plenty of work to still be done, but we could be looking at an exciting new development here, giving the ability to communicate back to people who lost it.

“Our results open a new approach for BCIs and demonstrate the feasibility of accurately decoding rapid, dexterous movements years after paralysis,” the researchers write.

“We believe that the future of intracortical BCIs is bright.”

The findings are reported in Nature.

 

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Astronomers Detect a ‘Tsunami’ of Gravitational Waves. Here’s Where They’re Coming From

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The most recent gravitational wave observing run has netted the biggest haul yet.

In less than five months, from November 2019 to March 2020, the LIGO-Virgo interferometers recorded a massive 35 gravitational wave events. On average, that’s almost 1.7 gravitational wave events every week for the duration of the run.

 

This represents a significant increase from the 1.5-event weekly average detected on the previous run, and a result that has plumped up the number of total events to 90 since that first history-making gravitational wave detection in September 2015.

“These discoveries represent a tenfold increase in the number of gravitational waves detected by LIGO and Virgo since they started observing,” said astrophysicist Susan Scott of the Australian National University in Australia.

“We’ve detected 35 events. That’s massive! In contrast, we made three detections in our first observing run, which lasted four months in 2015-16. This really is a new era for gravitational wave detections and the growing population of discoveries is revealing so much information about the life and death of stars throughout the Universe.”

Of the 35 new detections, 32 are most likely the result of mergers between pairs of black holes. This is when pairs of black holes on a close orbit are drawn in by mutual gravity, eventually colliding to form one single, more massive black hole.

That collision sends ripples through space-time, like the ripples generated when you throw a rock in a pond; astronomers can analyze those ripples to determine the properties of the black holes.

mergersAn infographic showing the masses of all black hole mergers announced to date. (LIGO-Virgo/Aaron Geller/Northwestern University)

The data revealed a range of black hole masses, with the most massive clocking in at around 87 times the mass of the Sun. That black hole merged with a companion 61 times the mass of the Sun, resulting in a single black hole 141 times the mass of the Sun. That event is named GW200220_061928.

Another merger produced a black hole 104 times the mass of the Sun; both of these are considered intermediate mass black holes, a mass range between 100 and around a million solar masses, in which very few black holes have been detected.

 

GW200220_061928 is also interesting, because at least one of the black holes involved in the merger falls into what we call the upper mass gap. According to our models, black holes over about 65 solar masses can’t form from a single star, as stellar mass black holes do.

That’s because the precursor stars are so massive that their supernovae – known as pair-instability supernovae – ought to completely obliterate the stellar core, leaving nothing behind to gravitationally collapse into a black hole.

This suggests that the 87 solar mass black hole might be the product of a previous merger. GW200220_061928 isn’t the first that’s involved a black hole in the upper mass gap, but its detection does suggest that hierarchical black hole mergers are not uncommon.

And another event includes an object in the lower mass gap – a gap of black holes between 2.5 and 5 times the mass of the Sun. We’ve not conclusively found a neutron star larger than the former, or a black hole smaller than the latter; the event named GW200210_092254 involved an object clocking in at 2.8 solar masses. Astronomers have concluded that it’s probably a very small black hole.

 

“Looking at the masses and spins of the black holes in these binary systems indicates how these systems got together in the first place,” Scott said.

“It also raises some really fascinating questions. For example, did the system originally form with two stars that went through their life cycles together and eventually became black holes? Or were the two black holes thrust together in a very dense dynamical environment such as at the centre of a galaxy?”

The other three events out of the 35 involved a black hole and something else much less massive, likely a neutron star. These events are of great interest to astronomers, since they might reveal the stuff that’s inside a neutron star – if we ever detect one that emits light. By finding more of these mergers, we can start to build a better understanding of how they actually occur.

“Only now are we starting to appreciate the wonderful diversity of black holes and neutron stars,” said astronomer Christopher Berry of the University of Glasgow in the UK

“Our latest results prove that they come in many sizes and combinations – we have solved some long-standing mysteries, but uncovered some new puzzles too. Using these observations, we are closer to unlocking the mysteries of how stars, the building blocks of our Universe, evolve.”

The team’s paper has been submitted for publication, and can be found on preprint server arXiv.

 

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