Transcript

6.18.26 · Science Show KY

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Speaker 1: Welcome to Radioized Diary of Science and Nature. The reader's
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Speaker 1: killing Taylor. I'll have articles on topics of science and nature.
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Speaker 1: But first a reminder. RADIOI is a reading service intended
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Speaker 1: for people who are blind or have other disabilities that
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Speaker 1: make it difficult to read printed material. We'll start with
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Speaker 1: an article from ACCU weather. El Nino is here, and
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Speaker 1: it's developing earlier and faster than many typically do. This
0:29
Speaker 1: is June eleventh. El Nino has developed in the Pacific Ocean,
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Speaker 1: a climate pattern that can reshape weather around the globe
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Speaker 1: into twenty twenty seven. The last Alnino was in twenty
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Speaker 1: twenty three twenty four, and forecasters say this one is
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Speaker 1: developing earlier than many typically do. Quote the sea surface
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Speaker 1: temperatures are quickly changing in the equatorial Pacific, says ACU
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Speaker 1: weather long range expert Paul Pasteloch. By early June, the
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Speaker 1: water in this vision had risen by at least zero
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Speaker 1: point nine of a degree fahrenheit, reaching a threshold associated
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Speaker 1: with al Nino conditions. Most el Nino's begin in the fall,
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Speaker 1: so this is developing much earlier and faster than expected,
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Speaker 1: says Aci Weeather, senior meteorologist Chad Merrill. The weather patterns
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Speaker 1: here early in the summer are also lining up to
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Speaker 1: what is expected with an al nino. ACI weather experts
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Speaker 1: say there is a forty percent chance it evolves into
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Speaker 1: a super al nino. To reach that level, water near
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Speaker 1: the equator in the Eastern Pacific would need to climb
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Speaker 1: at least three point six degrees fahrenheit above the long
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Speaker 1: term average. The stronger al nino becomes, the greater its
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Speaker 1: potential influence on weather patterns around the world. As of
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Speaker 1: early June, water in the Eastern Pacific was already running
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Speaker 1: at exceptional levels. Climate Central reported the warmth was higher
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Speaker 1: than in any year since nineteen eighty two. El Nino
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Speaker 1: is not the only factor that long range forecasters are watching.
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Speaker 1: Other parts of the Pacific are also unusually warm. Warming
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Speaker 1: water between Hawaii and the Baja can help feed into
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Speaker 1: the warming near the equator to increase al nino Pastiloc
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Speaker 1: added there is also a broad area of warm water
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Speaker 1: that stretches over three thousand miles from near Japan to
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Speaker 1: north of Hawaii, which is much warmer than historical averages. Together,
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Speaker 1: those factors could make this al nino look different from
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Speaker 1: others In recent history. Some alinho q and a can
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Speaker 1: al Nino make landfall. No and Alino is not a storm.
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Speaker 1: It does not affect you directly. Pastiloch explained. It is
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Speaker 1: a cycle that contributes, like many other factors, to produce
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Speaker 1: weather changes and sometimes extremes. What does Alnino mean for
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Speaker 1: summer weather? It depends on where you live. In United States,
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Speaker 1: severe weather and tornadoes can increase in the central and
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Speaker 1: eastern US during the summer, while other reason regions experience
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Speaker 1: drier conditions. It will intensify drought in the Northwest and
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Speaker 1: northern Rockies and lessen drought intensity and coverage in the Southwest.
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Speaker 1: It won't do anything to eliminate the long term drought
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Speaker 1: in the southeast and mid Atlantic until we get to
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Speaker 1: late fall and early winter. What does this mean for
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Speaker 1: hurricane season? While Alnino may lower the total storm count,
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Speaker 1: it will not shut down the Atlantic hurricane season, says
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Speaker 1: ACI Weather lead hurricane expert alexd Silva. One storm can
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Speaker 1: define an entire season. Elnina was in place at the
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Speaker 1: start of the nineteen ninety two Atlantic hurricane season, which
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Speaker 1: is remembered for Hurricane Andrews devastating Category five strike on Florida,
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Speaker 1: even though the season produced only seven named storms, well
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Speaker 1: below the historical average of fourteen. Meanwhile, warmer Pacific waters
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Speaker 1: can help fuel tropical activity in the eastern and central
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Speaker 1: Pacific basins, increasing the risk of impacts for Mexico, Hawaii,
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Speaker 1: and in some setups California. How long will Allino last?
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Speaker 1: Aci Weather expects al Nino to continue into at least
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Speaker 1: the start of twenty twenty seven, but the impacts could
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Speaker 1: last even longer. Its influence is often more pronounced in
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Speaker 1: winter than in summer or autumn. Typically, Alnina winters are
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Speaker 1: stormy across California and the Southwest, raising the risk of
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Speaker 1: flooding while also helping to fill vital reservoirs. It can
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Speaker 1: also lead to wetter and cooler conditions across the Gulf Coast. Meanwhile,
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Speaker 1: winters tend to be less cold and have less rain
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Speaker 1: and snow across the northern half of the US. Now
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Speaker 1: we'll turn to BBC Wildlife. No one's ever seen Tiger's
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Speaker 1: New this before. A film crew flew a drone over
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Speaker 1: an island full of big cats and captured something extraordinary.
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Speaker 1: This is from June sixteenth, as it is one of
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Speaker 1: the most iconic animals on the planet. You would be
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Speaker 1: forgiven for thinking that people know everything there is to
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Speaker 1: know about tigers, but new footage shot for the BBC's
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Speaker 1: Tiger Island proves this isn't the case and has scientists
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Speaker 1: completely surprised. Shot in Nepal, Tiger Island follows a team
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Speaker 1: of wildlife filmmakers and a big cat and Big Cat
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Speaker 1: experts on an expedition to reveal the secret lives of tigers.
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Speaker 1: The team focuses on in on a small island measuring
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Speaker 1: just four square kilometers in a river system in western Nepal,
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Speaker 1: which is home to one of the highest concentrations of
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Speaker 1: tigers on Earth. Following the tigers over two months, the
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Speaker 1: tea get to know individual tigers by studying their stripes,
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Speaker 1: none of which are the same. Using drones, they follow
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Speaker 1: the tigers as they live on the land, live on
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Speaker 1: the island, and in this clip discovers something startling about them.
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Speaker 1: Tigers are famously considered to be solitary, with only mothers
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Speaker 1: and their cubs living together. Quote. They are supposed to
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Speaker 1: be incredibly territorial, explains Dan O'Neill, a Big Cat scientist
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Speaker 1: working on the series. Quote females do not cross paths
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Speaker 1: unless they absolutely have to. They don't share cubs, they
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Speaker 1: don't share parenting duties. End quote. But using a drone
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Speaker 1: to capture footage of tiger behavior, the team discovered that
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Speaker 1: this isn't strictly the case. One mother tiger called Goma,
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Speaker 1: who has two cubs, ends up looking after five with
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Speaker 1: three cubs from a different mother, Jugini. While Gughini is
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Speaker 1: a little distance away eating, Goma cares for all the
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Speaker 1: cubs on her own. I have never seen this kind
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Speaker 1: of thing, one mother leaving her cubs with another. This
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Speaker 1: is definitely something different, says Manju Mahatara, a local tiger
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Speaker 1: guide who worked on Tiger Island. One theory that could
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Speaker 1: explain why this happens is that it could be a
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Speaker 1: response to the threat posed by males helping to keep
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Speaker 1: the cubs safe while one parent is busy. The two
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Speaker 1: adult tigers filmed, Goma and gu Guinea, are thought to
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Speaker 1: be related, with Goma possibly being the mother of geu Guinea.
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Speaker 1: Gugini is not often seen in the same area as Goma,
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Speaker 1: but when she is, she seems to interact peacefully with
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Speaker 1: the other tigers'es quote One mother is looking after all
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Speaker 1: the cubs while the other is eating. No one has
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Speaker 1: ever seen tigers do this before, says O'Neil. I was
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Speaker 1: about to say tigers are solitary big cats, are they?
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Speaker 1: I don't know any more. You just don't imagine that
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Speaker 1: there are things to learn still about the most iconic
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Speaker 1: animal on the planet. But there it is, and it's
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Speaker 1: here now. An article from National Geographic why you may
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Speaker 1: see more black bears this summer. This is from June sixteenth.
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Speaker 1: As spring officially gives a way to summer, black bear
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Speaker 1: sightings spike across the United States. This is because the
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Speaker 1: bruins have awoken from hibernation and several months in repose
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Speaker 1: have left them with a bad case of the munchies.
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Speaker 1: During hibernation, black bears are essentially in torpoor or asleep
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Speaker 1: for three to four months, says Carrie Kingaree, wildlife program
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Speaker 1: manager for the Confederated Salish and Kutani tribes, of which
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Speaker 1: she is also a member. Quote, but they wake up
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Speaker 1: and their energy reserves are highly depleted, so they're very hungry.
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Speaker 1: In quote. The caloric deficit incurred by hibernation is so
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Speaker 1: deep it takes more bears until mid July before they
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Speaker 1: can get back to their base weight and start building
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Speaker 1: back energy stores for the next winter. In the meantime,
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Speaker 1: they usually easily I'm sorry. In the meantime they use
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Speaker 1: easily available sources of human food to build their supply
9:18
Speaker 1: back up. Quote. We have bird feeders, We have garbage
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Speaker 1: cans that are waiting to be picked up on Tuesday morning.
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Speaker 1: There are cat foods and dog foods on porches, says Kingery.
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Speaker 1: But free food isn't the only thing causing black bears
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Speaker 1: to move around this time of year. Bears are mating
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Speaker 1: right now. In fact, just this week some landowners nearby
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Speaker 1: have caught some footage of interactions happening, says Kingery. They're
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Speaker 1: moving around, especially those males moving from female to female
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Speaker 1: in that kind of search mode, so they are covering
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Speaker 1: a bit more ground end quote. There are three species
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Speaker 1: of bear in the United States, but American black bears
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Speaker 1: are by far the most common, with a range that
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Speaker 1: extends from the Arctic circle to central Mexico. Black bears
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Speaker 1: can be found across a range of habitats, most notably
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Speaker 1: forests and scrublands, but also swamps. Today, there are more
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Speaker 1: than three hundred thousand black bears in the US alone.
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Speaker 1: The reason we talk about black bears so much, the
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Speaker 1: reason people see them so often, the reason that they
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Speaker 1: are such a big part of North American life is
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Speaker 1: because of the conservation work that's been done to bring
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Speaker 1: them back, says Ray Wynn Grant, a National geographic explorer
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Speaker 1: and co host of Mutual Olmaha's Wild Kingdom Protecting the Wild.
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Speaker 1: Just as recently as the year nineteen hundred, unregulated hunting
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Speaker 1: and massive deforestation had eradicated black bears from fifty five
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Speaker 1: percent of their historic range. But then in nineteen thirty seven,
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Speaker 1: Congress passed the Pittman Robertson Federal Aid and Wildlife Restoration Act,
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Speaker 1: which redirected an existing tax on firearms and ammunition to
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Speaker 1: instead benefit species restoration. It would take another twenty years
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Speaker 1: before any of that money was used to benefit black
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Speaker 1: bear science and conservation, but the gains since then have
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Speaker 1: been huge. Black bear populations have rebounded in around sixty
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Speaker 1: percent of their historic range. But even with all of
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Speaker 1: that conservation's success, people are seeing more black bears than
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Speaker 1: ever before. Thanks to a relatively recent technological advance, we
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Speaker 1: have all these ring cameras and home security doorbells, where
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Speaker 1: you can look at your phone every second and know
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Speaker 1: if there's a bear walking through your yard, says When Grant,
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Speaker 1: who is also a wildlife ecologist who has studied black
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Speaker 1: bears for the last fifteen years. Quote where has just
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Speaker 1: a few years ago? If it happened and you weren't home,
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Speaker 1: where you weren't looking, you would have no idea there
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Speaker 1: was a bear there. End quote. Though black bears can
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Speaker 1: reach sizes exceeding six hundred pounds, they tend to be
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Speaker 1: very quiet creatures. Without twenty four to seven motion activated cameras,
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Speaker 1: many people would never even know the bruins stopped to
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Speaker 1: buy for a visit. Quote. There's a huge difference between
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Speaker 1: a bear sighting and a bear conflict, says wind Grant.
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Speaker 1: There's also a big difference between a bear being aggressive
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Speaker 1: and a bear attack because bears don't want to fight.
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Speaker 1: In general, black bears don't view humans as food, nor
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Speaker 1: do they want to spend any more energy than they
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Speaker 1: have to. When a black bear is displaying aggression, stomping
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Speaker 1: its feet, clacking its jaws, or even making short, fast
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Speaker 1: charges in the direction of a human, they're usually trying
12:35
Speaker 1: to scare a person away not hurt them. I'm going
12:40
Speaker 1: to go on record as saying the average bear will
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Speaker 1: go its entire life without getting into a fight. Says
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Speaker 1: win Grant. The best way to mitigate black bear conflict
12:48
Speaker 1: is to put distance between yourself and the bruin. However,
12:52
Speaker 1: don't just turn and run, which might make you look
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Speaker 1: like prey. Rather make yourself appear large by waving your
12:58
Speaker 1: hands and calling out to the bear, all while backing
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Speaker 1: away steadily. If a bear encounter progresses past this point, though,
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Speaker 1: both win Grant and Kingery recommend bear spray. Bear spray
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Speaker 1: is the best deployed before the bear is running at you,
13:17
Speaker 1: says win Grant. Putting cloud of pepper spray between you
13:21
Speaker 1: and the bear means the animal has to breathe it
13:23
Speaker 1: in before it can get to you. As a bear
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Speaker 1: is running towards you, it's really like puffing and sucking
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Speaker 1: air in through its nostrils and the capsaican is hitting
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Speaker 1: that incredibly sensitive olfactory system, says Kingery. As for preventing
13:38
Speaker 1: conflict with black bears at home, cleaning your backyard grill
13:42
Speaker 1: after cooking and using bear proof garbage containers can go
13:45
Speaker 1: a long way, But when grant does also have some
13:49
Speaker 1: bad news. I really bum a lot of people out
13:52
Speaker 1: by saying, I know you really love your bird feeder
13:55
Speaker 1: because it attracts some really cool birds, but it is
13:58
Speaker 1: also a calorie haven for black bears. She says. Okay,
14:05
Speaker 1: now we're going to turn to Science Alert, and this
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Speaker 1: article from June the fifteenth says scientists finally discover how
14:13
Speaker 1: venus fly traps snap shut so fast to succeed in
14:18
Speaker 1: a hunt. A predator often needs to be faster than
14:21
Speaker 1: its prey. Plants are not known for their speed, even so,
14:25
Speaker 1: one plant has evolved a snappy survival strategy that lets
14:29
Speaker 1: it feast on insects and arachnids that, by most measures,
14:34
Speaker 1: should be safe from its clutches. We're talking, of course,
14:37
Speaker 1: about the famous venus fly trap, a plant that lures
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Speaker 1: prey into a leafy trap, then snap shut around the
14:44
Speaker 1: unfortunate victim, holding it fast while the plant digests at
14:48
Speaker 1: its leisure. Scientists have long puzzled over the mechanism that
14:52
Speaker 1: allows this plant to move faster than plants should be
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Speaker 1: able to. Now, a team of researchers led by physicist
14:59
Speaker 1: Jong Review of the French National Center of Scientific Research
15:05
Speaker 1: say they have identified the trigger to activate its jaws.
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Speaker 1: The plant rapidly softens the cell walls in the trap's
15:13
Speaker 1: outer skin. That change lets the outer surface expand more
15:18
Speaker 1: easily than the inner surface, bending the leaf until it
15:21
Speaker 1: reaches a tipping point and snaps shut. Our finding reveals
15:26
Speaker 1: a mode of plant motility based on dynamic tuning of
15:31
Speaker 1: material properties, suggesting principles for muscle free, bio inspired actuation.
15:40
Speaker 1: Many plants can achieve relatively timely and precise movement. One
15:43
Speaker 1: of the most famous examples is seen in Mimosa pu pudica,
15:48
Speaker 1: or Touch me Not, whose symmetrical leaflets fold shut when touched,
15:53
Speaker 1: a delicate maneuver thought to help the plant evade predation
15:57
Speaker 1: or minimize damage from passers by. For a lot of plants,
16:01
Speaker 1: these movements are powered by the flow of fluid, simple
16:05
Speaker 1: hydraulics that change internal pressure and thus the shape of
16:08
Speaker 1: the plant. Previously, scientists had supposed that the mechanism behind
16:13
Speaker 1: the fly trap's movements was similarly hydraulic, but that posed
16:17
Speaker 1: a problem. The traditional hydraulic idea was that the trap
16:22
Speaker 1: closes because water moves from one side of the leaf
16:25
Speaker 1: to the other, causing one side to expand more than
16:28
Speaker 1: the other and bend the trap shut. The researchers identified
16:34
Speaker 1: two main flaws with this model. The first is that
16:37
Speaker 1: water moves relatively slowly through plant tissue. The researchers measured
16:41
Speaker 1: how quickly water moves through a venus fly trap and
16:44
Speaker 1: estimated that transporting water across the thickness of the trap
16:48
Speaker 1: would take between thirty and one hundred and fifty seconds.
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Speaker 1: That's far too slow for the speed at which a
16:54
Speaker 1: fly trap needs to operate. Sure Enough, the movements that
16:58
Speaker 1: initiate closure occur on a timescale of about a second,
17:02
Speaker 1: much faster than water could move through the trap. The
17:05
Speaker 1: other problem is that a water driven mechanism should produce
17:08
Speaker 1: a delayed wave of motion across the trap as water
17:11
Speaker 1: gradually diffuses through the tissue, But the researchers found no
17:15
Speaker 1: sign of such a pattern. Well, the next question, naturally, is,
17:19
Speaker 1: if not hydraulics, then what is it. In their new study,
17:22
Speaker 1: the researchers described the two stage process of a snap.
17:27
Speaker 1: The first is the active bending phase, in which the
17:30
Speaker 1: trap begins to bend inward toward a critical tipping point.
17:34
Speaker 1: The second is the snap closure itself, which takes just
17:38
Speaker 1: zero point two seconds. To isolate what kicks off the
17:42
Speaker 1: active phase, the researchers devised two tests. In the first,
17:46
Speaker 1: traps were cut into thin strips to hinder the snapping mechanism.
17:50
Speaker 1: Under this condition, the traps were still able to bend,
17:52
Speaker 1: but much more slowly. In the second test, traps were
17:56
Speaker 1: clamped open and equipped with a force sensor to measure
17:59
Speaker 1: the force required to maintain separation between the two lobes.
18:03
Speaker 1: This produced a similar result, revealing a gradual bending motion
18:08
Speaker 1: that precedes the rapid snap buckling stage. The final piece
18:13
Speaker 1: of the puzzle was observing what the plant is actually
18:15
Speaker 1: doing during that active bending phase. The researchers used a
18:19
Speaker 1: tiny probe to measure the stiff cellulosic walls of the
18:24
Speaker 1: cells inside and outside the trap before and after closure.
18:29
Speaker 1: Cell walls on the inner surface barely changed, but those
18:32
Speaker 1: on the outer surface softened, losing about forty percent of
18:36
Speaker 1: their rigidity. So here's how it works. Before triggering turger pressure,
18:42
Speaker 1: the force inside a cell that pushes the cell membrane
18:45
Speaker 1: against the cell wall is evenly distributed across the inner
18:50
Speaker 1: and outer walls of the trap. When a crawling critter
18:53
Speaker 1: triggers the trap by touching one of the sensitive filaments
18:57
Speaker 1: inside it twice in quick success. The outer wall softens
19:03
Speaker 1: that allows the outer surface to expand more readily than
19:06
Speaker 1: the inner surface, creating a mismatch that bends the leaf
19:12
Speaker 1: in a relatively short space of time. This bending passes
19:16
Speaker 1: the snap instability threshold and the lobes slam shut, allowing
19:22
Speaker 1: the plant to respond quickly enough to a trigger to
19:25
Speaker 1: snap up a lovely dinner. Here's the wild bit, though,
19:29
Speaker 1: that cell wall softening is essentially how plants grow. Venus
19:34
Speaker 1: light traps essentially dialed up a tool they already had
19:37
Speaker 1: in their genetic kit so they could take a more
19:39
Speaker 1: proactive approach to securing nutrients. Quote. These fine tune adaptations
19:45
Speaker 1: that allow plants to have the upper hand when interacting
19:47
Speaker 1: with animals raise another question, how can they arise from
19:51
Speaker 1: a trial and error revolutionary process? Writes bioengineer Jock Dumay
19:56
Speaker 1: of the Adolfo Ibanez University in Chile. We now know
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Speaker 1: how the venus fly trap works its magic, but it
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Speaker 1: hasn't lost its allure. Not while those bigger evolutionary questions
20:08
Speaker 1: remain to be answered. Now From USA today, San Andres
20:15
Speaker 1: fault stress hits one thousand year high, raising quake risk.
20:21
Speaker 1: This is from June to fifteenth. Tectonic stress along southern
20:25
Speaker 1: California's San Andres and San Jacinto fault systems has reached
20:30
Speaker 1: and in some areas exceeded the highest level seen in
20:34
Speaker 1: the past one thousand years, according to new research led
20:38
Speaker 1: by earth scientists at the University of Hawaii at Manoa.
20:43
Speaker 1: Researchers say the system is not showing signs of an
20:46
Speaker 1: imminent rupture, but is operating under unusually high stress in
20:51
Speaker 1: a long term seismic cycle that could support large earthquakes,
20:56
Speaker 1: including multi fault events. The study, published in the Journal
21:02
Speaker 1: of Geophysical Research, suggests the region is in a critically
21:07
Speaker 1: loaded state that's in quotes, with stress building across multiple
21:12
Speaker 1: fault segments. One key area a focus is Cahoon Pass,
21:17
Speaker 1: a junction between the two fault systems that may act
21:20
Speaker 1: as an earthquake gait that's also in quotes, either blocking
21:25
Speaker 1: ruptures from crossing between faults or allowing them to link
21:29
Speaker 1: into a single larger event. Lead author LILLIANE. Burkhard, a
21:34
Speaker 1: research affiliate at the University of Wise Institute of Geophysics
21:38
Speaker 1: and Planetology, and scientists at the University of Berne said
21:43
Speaker 1: the system is highly stressed after more than one hundred
21:46
Speaker 1: and sixty years since the last major rupture quote right now.
21:52
Speaker 1: With stress at historically high levels across the region in
21:55
Speaker 1: more than one hundred and sixty years elapsed since the
21:57
Speaker 1: last major rupture, the system is in a critically loaded state,
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Speaker 1: Burkhard said. Researchers say a rupture involving both fault systems
22:08
Speaker 1: could be significantly more damaging than a single fault earthquake
22:12
Speaker 1: due to its size and proximity to major population centers,
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Speaker 1: including Los Angeles, San Bernardino, Riverside, and the Coachella Valley.
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Speaker 1: The Sanadres fault is not a crack that can split
22:25
Speaker 1: open and drop a chunk of California away from the continent.
22:30
Speaker 1: It's a strike slip plate boundary, meaning the Pacific plate
22:34
Speaker 1: and North American plate or sliding past each other horizontally,
22:38
Speaker 1: not pulling apart. That's according to a US geological survey.
22:42
Speaker 1: So even in a very large earthquake, what happens is
22:46
Speaker 1: sideways movement along the fault, not a breakup of the
22:49
Speaker 1: land mass. Parts of California can shift suddenly by feet
22:53
Speaker 1: or even tens of feet during a major rupture, but
22:57
Speaker 1: both sides remain part of the same crustal system. There
23:01
Speaker 1: are other tectonic settings on Earth where continents rift apart
23:06
Speaker 1: and eventually form new oceans, such as the East African Rift,
23:10
Speaker 1: which is in the process of splitting into two tectonic plates,
23:14
Speaker 1: but the San Andreas system is not one of them.
23:17
Speaker 1: It is a strike slip boundary where plates slide past
23:21
Speaker 1: each other rather than spreading apart. However, over millions of years,
23:26
Speaker 1: continued movement along the fault could gradually bring Los Angeles
23:30
Speaker 1: and San Francisco into closer proximate proximity. Geologic models suggest
23:37
Speaker 1: surface rupture occurs when movement along a fault deep within
23:40
Speaker 1: the Earth breaks through to the surface. According to the
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Speaker 1: Pacific Northwest Seismic Network, it is one of the clearest
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Speaker 1: physical expressions of an earthquake, showing permanent deformation where two
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Speaker 1: sides of a fault slip past one another. Most earthquakes
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Speaker 1: do not produce surface rupture. Some fault do not reach
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Speaker 1: the surface, and even when they do, rupture does not
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Speaker 1: always propagate all the way upward during a given event.
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Speaker 1: When surface rupture occurs, it can produce either horizontal or
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Speaker 1: vertical offsets, depending on the type of fault strike. Slip
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Speaker 1: faults such as san andres typically cause horizontal displacement, whereas
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Speaker 1: dip slip faults can produce vertical displacement. Some earthquakes involve
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Speaker 1: a combination of both. In a major rupture, strong shaking
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Speaker 1: could last tens of seconds to more than a minute.
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Speaker 1: The most severe damage would occur near the fault and
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Speaker 1: in areas built on soft or water saturated soils, which
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Speaker 1: can amplify shaking and increase the risk of liquefaction. Scientists
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Speaker 1: note that infrastructure built across active faults is especially vulnerable,
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Speaker 1: as surface rupture can directly offset roads, buildings, and other
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Speaker 1: structures that span the fault trace. The Earth has four layers,
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Speaker 1: the inner core, the outer core, the mantle, and the crust.
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Speaker 1: The crust and top of the mantle make up another
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Speaker 1: area called the lithosphere, which acts like a skin surrounding
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Speaker 1: the Earth's surface. The lithosphere, however, is not a single piece,
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Speaker 1: but is divided into puzzle like fragments called tectonic plates.
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Speaker 1: These parts of the lithosphere are not stationary and move
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Speaker 1: slowly as tectonic plates move past one another, they occasionally
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Speaker 1: bump or collide. This place is stress on the plate's edges.
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Speaker 1: When the stress becomes too great, it creates cracks called faults.
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Speaker 1: The point where these faults move against each other is
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Speaker 1: called the fault line. When there is too much friction
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Speaker 1: between the fault lines, energy is suddenly released, triggering seismic
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Speaker 1: waves that cause an earthquake. California sits along the boundary
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Speaker 1: between two massive tectonic plates, the Pacific Plate and the
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Speaker 1: North American Plate. These plates are constantly moving, sliding past
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Speaker 1: one another at different speeds. The state is also home
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Speaker 1: to more than five hundred active faults, making it one
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Speaker 1: of the most earthquake prone regions in the United States.
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Speaker 1: The most famous is San Andreas Fault, a roughly eight
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Speaker 1: hundred miles system that runs through much of the state
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Speaker 1: and forms the primary boundary between the two plates. Other
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Speaker 1: major fault systems include the Hayward Fault in the Bay Area,
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Speaker 1: the Calaveras Fault in central California, and the San Jacinto
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Speaker 1: and Elsinore faults in southern California. But earthquakes are not
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Speaker 1: limited to land. Many occur offshore, including near the Mendocino
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Speaker 1: Triple junction, where the Pacific, North American, and Gorda plates
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Speaker 1: all meet. That junction creates one of the most seismically
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Speaker 1: active offshore regions along the West Coast. Earthquakes are not predicted.
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Speaker 1: Neither the US Geological Survey nor scientists have predicted a
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Speaker 1: major earthquake, and there's no expectation that this will change
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Speaker 1: in the near future. California's earthquake early warning system uses
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Speaker 1: seismic sensors, ground emotion monitoring, and alerting technology to deliver
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Speaker 1: warnings to people via cell phones before the strongest shaking arrives.
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Speaker 1: Officials say even a brief warning can allow people to
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Speaker 1: take protective actions such as drop, cover and hold on,
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Speaker 1: or put devices and systems into a safe mode. In
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Speaker 1: some cases, alerts may arrive just as shaking begins or
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Speaker 1: after an earthquake has already passed, particularly for those closer
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Speaker 1: to the epicenter. The system is delivered through multiple channels,
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Speaker 1: including Android earthquake alerts, wireless emergency alerts, and the my
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Speaker 1: shake app developed by the UC Berkeley Seismological Laboratory. My
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Speaker 1: Shake is a free smartphone application that issues audio and
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Speaker 1: visual warnings for earthquakes typically magnitude four point five or greater,
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Speaker 1: or when weak shaking is expected. It is available on
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Speaker 1: I phone and Android devices, as well as select computer platforms.
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Speaker 1: That's all for today's Diary of science and nature. Your
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Speaker 1: reader was Kelly Taylor, and stay tuned for further programming
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Speaker 1: on RADIOI