Transcript

9.3.26 · Science Show KY

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Speaker 1: Welcome to Radio Eye's Diary of Science and Nature. Your
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Speaker 1: reader's Kelly Taylor. I'll have some stories on the topics
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Speaker 1: of science and nature, but first a reminder that Radio
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Speaker 1: Eye is a reading service intended for people who are
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Speaker 1: blind or have other disabilities that make it difficult to
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Speaker 1: read printed material. We're dealing with a little bit of
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Speaker 1: a chest cold today, so excuse me if I cough
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Speaker 1: now and then. I'll try to avoid it. Dated August 30th,
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Speaker 1: This article from The Atlantic is headlined, This El Nino
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Speaker 1: will be unlike any in the past eight decades. Written
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Speaker 1: by Joshua Partlow. In the middle of the Pacific Ocean
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Speaker 1: along the equator, scientists have drawn a box. It's a
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Speaker 1: big box, two-thirds the size of China. Yet, hardly anyone
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Speaker 1: lives inside it. This rectangular swath of open ocean is
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Speaker 1: monitored by satellites and a network of moored buoys that
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Speaker 1: measure minute changes in the temperature of the water with
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Speaker 1: an eye toward anomalies. Every few years or so, driven
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Speaker 1: by changing winds and currents, the water temperature in this
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Speaker 1: part of the ocean starts to rise. Even a half
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Speaker 1: degree Celsius above normal over months warrants a designation that
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Speaker 1: an El Nino phase has begun. That's enough warming to
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Speaker 1: unleash floods and fires, drought and famine around the world.
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Speaker 1: The box is called Nino 3.4. Right now, it's hot
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Speaker 1: in the box. Quote, like a baby pool, says Christina Teichin,
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Speaker 1: who spent most of August scuba diving in the middle
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Speaker 1: of this mass of abnormally warm water. Teichin has been
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Speaker 1: coming to the world's largest atoll, Kiritimati, for more than
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Speaker 1: a decade to study its coral reefs. She usually dives
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Speaker 1: in a medium-weight wetsuit. This trip, her team needed only
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Speaker 1: rash guards. It is still early in this El Nino cycle,
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Speaker 1: which is likely to be the strongest ever recorded. But
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Speaker 1: the waters around Kiritimati have already been 3 to 4
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Speaker 1: degrees Celsius above normal. Tait Jin's time on Kiratamati, and
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Speaker 1: it says here in parentheses, pronounced like Christmas, okay? It's
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Speaker 1: spelled K-I-R-I-T-I-M-A-T-I, pronounced like Christmas. The time there has allowed
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Speaker 1: her to watch in brutal detail what these repeated warm
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Speaker 1: water cycles playing out in a steadily warming ocean mean
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Speaker 1: for the great tropical coral reefs here, which were once
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Speaker 1: near pristine. During her first El Nino in 2015 and 16,
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Speaker 1: 90% of Christmas's coral reef died. Years of slow, partial
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Speaker 1: recovery followed. This month, Teichen and her colleagues, part of
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Speaker 1: the Canadian scientist Julia Baum's lab at the University of Victoria,
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Speaker 1: discovered that nearly half of the island's remaining corals had
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Speaker 1: already bleached. a prelude, if warming persists, to death. When
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Speaker 1: Taijin comes back, she may well be swimming over a graveyard.
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Speaker 1: Most of the world experiences El Niño' s ripple effects as
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Speaker 1: the heat building up in the equatorial Pacific radiates into
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Speaker 1: the atmosphere and around the globe. This means great gouts
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Speaker 1: of rain and supercharged storms in some places. In other areas,
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Speaker 1: crop-killing dry spells that can extend for months. Along the
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Speaker 1: Pacific coast of South America, torrential rains and landslides have
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Speaker 1: forced the temporary closure of a main route to Machu
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Speaker 1: Picchu in Peru. Deadly floods have swept through arid regions
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Speaker 1: of northern Chile. Countries such as India and Ethiopia are
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Speaker 1: enduring some of their driest summers on record. El Ninos
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Speaker 1: tend to mean more rainfall across the southern United States
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Speaker 1: and drier stretches across a band in the north. Strong
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Speaker 1: El Ninos can mean record-breaking heat, and this one is
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Speaker 1: shaping up to be unlike any cataloged in the past
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Speaker 1: eight decades. A 2 degrees Celsius increase in the Nino 3.4
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Speaker 1: box typically means the title of Super El Nino. We're
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Speaker 1: already past that threshold, and experts project that the warming
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Speaker 1: could peak at roughly twice as high. Quote, We are
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Speaker 1: now pretty certain this will be an exceptional event. says
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Speaker 1: Malte Stuecker, the director of the International Pacific Research Center
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Speaker 1: at the University of Hawaii at Manoa. Part of the
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Speaker 1: reason Stuecker expects this warmth to keep building is that
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Speaker 1: the buoys along the equator can detect water temperatures well
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Speaker 1: below the surface. Down more than 100 meters, an enormous
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Speaker 1: mass of warm water has built up and will rise
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Speaker 1: to the surface in the months ahead. The amount of
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Speaker 1: heat brewing in the ocean has produced one of those
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Speaker 1: graphs in which the current year departs drastically from past
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Speaker 1: trend lines, wriggling up erratically into unfamiliar territory. Although scientists
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Speaker 1: continue to debate the extent to which climate change makes
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Speaker 1: El Nino cycles more frequent or intense, they agree that
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Speaker 1: these cycles are occurring in an ocean that is warmer
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Speaker 1: than it was. Last Saturday, the daily global average sea
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Speaker 1: surface temperature reached 21.1 degrees Celsius, or 70 degrees Fahrenheit,
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Speaker 1: its highest level on record. Even if El Nino cycles
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Speaker 1: are not changing at all as they spiral around that
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Speaker 1: ascending baseline, the temperature peaks they hit keep getting higher,
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Speaker 1: causing repeated blows to marine life and disrupting ecosystems in
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Speaker 1: a way that may be irrevocable. Carlos Zavalaca the director
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Speaker 1: of the Seabird Lab at the Universidad Científica de Sur
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Speaker 1: in Lima, began to comprehend the magnitude of this year's
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Speaker 1: warming in mid-June when he visited Maccabi and Guanape Norte,
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Speaker 1: two islands off the northern coast of Peru. He'd been
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Speaker 1: hearing from colleagues about dead birds washing up by the
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Speaker 1: hundreds on the coasts of Peru and Ecuador. He's seen
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Speaker 1: the news stories about flocks of hungry Peruvian pelicans swarming
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Speaker 1: the fish markets in port cities, looking for food. On
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Speaker 1: the two islands, which just last year were thronged with pelicans,
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Speaker 1: Inca terns, and Humboldt penguins, Zavalaca found empty nests, some
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Speaker 1: with eggs and starving chicks. They were abandoned islands, he
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Speaker 1: told me. These seabirds' feet on schools of anchovies swept
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Speaker 1: up in the Humboldt current, the cold, nutrient-rich, upwelling waters
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Speaker 1: that create bountiful fisheries off South America's Pacific coast. During
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Speaker 1: El Nino years, that current gets displaced by warmer waters
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Speaker 1: pushing east across the ocean, and these great schools of
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Speaker 1: feeder fish can vanish from the coasts. The decline has
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Speaker 1: been severe enough that Peru this month shut down an
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Speaker 1: anchovy fishery that is a key economic engine for the country,
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Speaker 1: with much of the year's quota unfulfilled. Long before satellite monitoring,
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Speaker 1: Peruvian fishermen noticed these cycles of warmer waters and dwindling
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Speaker 1: fish stocks. They named the phenomenon, which peaked around Christmas,
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Speaker 1: after the Christ child. References to El Niño in Peru's
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Speaker 1: scientific literature date back to the 19th century. In his
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Speaker 1: three decades studying seabirds, Zavalaga has witnessed die-offs before. but
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Speaker 1: it is the rapid-fire nature of these blows and the
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Speaker 1: severity of the disruptions that make him so concerned. Just
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Speaker 1: three years ago, the same year avian flu killed more
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Speaker 1: than 500,000 seabirds, another El Nino slammed into the coast
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Speaker 1: of Peru. The birds that had made a tenuous recovery
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Speaker 1: since then now face the prospect of another die-off. Zabalaga says, quote,
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Speaker 1: It's like a boxing match. You have a first knockout,
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Speaker 1: you try to recover quickly, and then you have a
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Speaker 1: second knockout. I cannot imagine what will be the scenario
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Speaker 1: by the end of this year, end quote. He doubted
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Speaker 1: that the birds could go extinct, but some species might
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Speaker 1: move farther south in search of colder waters. The coastline
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Speaker 1: in Peru and the culture that depends on the fish
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Speaker 1: and the birds could be permanently altered. When the warming started,
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Speaker 1: Around Christmas, one of the few populated islands in the
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Speaker 1: Nino 3.4 monitoring zone, Bill Newton, an island resident, was
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Speaker 1: fascinated by how evident the changes were. He told me
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Speaker 1: that the normally dry island turned sopping wet and regular
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Speaker 1: floods started washing out the roads. The wet brought swarms
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Speaker 1: of mosquitoes, but also clouds of dragonflies, which he hadn't
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Speaker 1: seen before. Higher than normal tides poured into seafront homes. Tuna,
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Speaker 1: which can do well in warmer water, attracted dozens of
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Speaker 1: fishing boats off the coast. Prevailing winds changed direction. Corals
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Speaker 1: have a particularly hard time when water warms. They can't
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Speaker 1: move elsewhere. and they are sensitive to heat stress. As
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Speaker 1: little as four weeks in water, just a degree warmer
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Speaker 1: than normal, can cause bleaching. The loss of the symbiotic
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Speaker 1: algae that supply corals food and brilliant colors, according to Baum,
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Speaker 1: whose lab Tijan works at. Baum, an ecologist, has studied
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Speaker 1: Christmas' reef since 2009. After the El Nino a decade
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Speaker 1: ago killed off nearly the entire reef, Baum began to
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Speaker 1: consider the possibility that she would witness the obliteration of
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Speaker 1: an ecosystem in her lifetime. In a 2018 paper in Science,
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Speaker 1: she projected that successive bleaching events could occur frequently enough
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Speaker 1: that coral reefs, which take roughly 10 to 30 years
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Speaker 1: to recover from mass mortality, would not have time to regrow.
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Speaker 1: In the years since, she had been hopeful that nature
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Speaker 1: could fight back as she watched surviving corals take up
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Speaker 1: symbionts that were more heat resistant. This year's warming and
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Speaker 1: the pace of bleaching already underway have dispelled that hope.
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Speaker 1: What happens next is in some ways predictable. El Nino
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Speaker 1: is not a haphazard force of destruction. It's a warming
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Speaker 1: phase in a specific area in the Pacific Ocean that
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Speaker 1: scientists have determined shifts the probabilities for certain weather outcomes
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Speaker 1: in various parts of the world. Those probabilities are reliable
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Speaker 1: enough that, for example, the U.S. Navy already plans to
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Speaker 1: send a hospital ship to the coast of Peru in
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Speaker 1: February to be in position to help after expected floods.
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Speaker 1: But as Baum and other scientists who study and love
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Speaker 1: the delicate ecosystems in the Equatorial Pacific are finding, just
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Speaker 1: because El Nino is a familiar cycle doesn't mean things
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Speaker 1: will be the same when this one is over. Now
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Speaker 1: turning to earth.com, honeybees can warn us when an ecosystem
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Speaker 1: is in trouble. Honeybees pick up traces of environmental stress
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Speaker 1: as they forage, making their health a potential early warning
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Speaker 1: system for ecosystem trouble. A honeybee doesn't know it's collecting data,
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Speaker 1: but every trip it makes, dipping into a puddle, landing
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Speaker 1: on a flower, or brushing against pollen, it picks up
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Speaker 1: a tiny sample of whatever's out there in the environment, pesticides, pollutants,
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Speaker 1: and other contaminants present in the landscape. Researchers now argue
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Speaker 1: that habit turns bees into something far more useful than
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Speaker 1: pollinators alone. It makes them living instruments for reading the
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Speaker 1: health of an entire ecosystem. The work was led by
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Speaker 1: an international team of scientists from the Sbarro Health Research Organization,
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Speaker 1: the local health authority of Foggia, Temple University, the University
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Speaker 1: Magna Grazia of Catanzaro, and the University of Siena. The
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Speaker 1: review leans on a framework called One Health, an approach
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Speaker 1: that treats human health, animal health, and ecosystem health as
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Speaker 1: one connected system rather than three separate categories. Bees, as
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Speaker 1: it turns out, sit almost exactly where those three categories overlap.
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Speaker 1: Pollination supports agricultural production and many of the foods that
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Speaker 1: humans eat. When bee populations struggle, the consequences don't stop
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Speaker 1: at the hive. They ripple outward into agriculture, food security,
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Speaker 1: and eventually into human welfare. A struggling colony isn't just
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Speaker 1: bad news for bees. It can be a warning sign
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Speaker 1: of something much bigger. Here's where the review pushes back
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Speaker 1: against a fairly common assumption, that the harm pesticides do
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Speaker 1: to bees should be measured mostly by whether the bees die.
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Speaker 1: That's too narrow a lens, the authors argue. Doses far
14:02
Speaker 1: too small to kill a bee outright. can still quietly
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Speaker 1: rewire its behavior, throw off its navigation, weaken its immune defenses,
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Speaker 1: disrupt reproduction, and destabilize the community of microbes living in
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Speaker 1: its gut. And these pressures rarely occur in isolation. Pesticides
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Speaker 1: layered on top of poor nutrition, disease, or other environmental
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Speaker 1: stress can compound their effect. That's exactly what makes bees
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Speaker 1: such good sentinels. A colony's overall health reflects the weight
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Speaker 1: of everything pressing on it at once, not just one
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Speaker 1: chemical measured in isolation. Quote, honeybees can be considered biological
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Speaker 1: sentinels of the environment because their health reflects the complex
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Speaker 1: interaction between chemical exposure, nutrition, pathogens, and ecological conditions, said
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Speaker 1: Antonio Giordano, founder and director of SHRO. quote, their protection
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Speaker 1: is therefore not simply a matter of safeguarding a single species.
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Speaker 1: It means protecting the ecological systems that sustain agriculture, biodiversity,
15:12
Speaker 1: and ultimately human health. What makes this framework generally worth
15:17
Speaker 1: paying attention to rather than just a nice way of
15:19
Speaker 1: thinking about ecology comes down to timing. The idea is
15:24
Speaker 1: that changes in bee health could reveal environmental pressure before
15:28
Speaker 1: it develops into broader, ecological, or food system consequences. Quote,
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Speaker 1: the concept of bees as sentinels perfectly embodies the One
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Speaker 1: Health approach. Monitoring honeybee health can provide an integrated view
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Speaker 1: of environmental stress while linking veterinary science, environmental surveillance, agriculture,
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Speaker 1: and human health, said Giovanna Liguri, executive director of the
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Speaker 1: One Health group. Quote, Bees can become an important early
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Speaker 1: warning system for environmental changes, helping us identify biological effects
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Speaker 1: before they translate into broader ecological and food system consequences.
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Speaker 1: End quote. Well, let's turn now to Smithsonian Magazine. This
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Speaker 1: article is headlined, What Triggered the Devastating Floods in Nepal
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Speaker 1: and Tibet? And Are We Due for More in the Future?
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Speaker 1: Here's what scientists know so far. This is from August 31st.
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Speaker 1: On August 26th, devastating flash floods washed away buildings, bridges,
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Speaker 1: and other infrastructure near the border between Nepal and China-governed Tibet.
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Speaker 1: The natural disaster has killed more than 900 people and
16:46
Speaker 1: left nearly 5,000 missing as of August 31st. Quote, It
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Speaker 1: was a huge gush of mud coming straight towards us,
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Speaker 1: recalls Kishav Prasad Baral, a 68-year-old survivor, to a team
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Speaker 1: of reporters. My wife is still somewhere beneath the mud.
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Speaker 1: She's gone, end quote. But what caused the catastrophic event
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Speaker 1: and could more like it happen in the future? Scientists
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Speaker 1: are still putting the pieces together. Here's what they know
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Speaker 1: so far. What caused the flooding? According to the U.S.
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Speaker 1: Geological Survey's August 27th update, an event in Nepal's Langthorn
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Speaker 1: National Park in the Himalayas triggered the flooding. The agency
17:31
Speaker 1: says that either a landslide carrying a glacier or a
17:36
Speaker 1: glacier collapse in which part of it snaps off may
17:39
Speaker 1: have generated the energy equivalent to a magnitude 5.2 earthquake.
17:44
Speaker 1: Then debris tumbled downward and triggered the floods. Many scientists
17:49
Speaker 1: are heavily leaning toward the landslide explanation. The physics of
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Speaker 1: the glacier collapse hypothesis didn't hold up, according to some
17:57
Speaker 1: natural hazards researchers in a group analyzing the event. What's more,
18:03
Speaker 1: satellite images obtained the evening of August 26th show a
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Speaker 1: bald mountain hinting at a giant landslide. Quote, the glacier
18:12
Speaker 1: just came along for the ride, says Goran Ekstrom, seismologist
18:16
Speaker 1: at Columbia University. However, experts still aren't sure where all
18:20
Speaker 1: the water came from. At first, scientists thought that a
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Speaker 1: glacial lake had collapsed, but satellite imagery and weather data
18:28
Speaker 1: didn't suggest any big ones were forming in the region.
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Speaker 1: It's more likely that the rush of ice and sediments
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Speaker 1: from the landslide accumulated river water as it barreled downstream,
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Speaker 1: according to Kristen Cook, a geomorphologist at Grenoble Alps University
18:43
Speaker 1: in France. The USGS says the glacial debris picked up
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Speaker 1: rocky material and water as it sped downhill, generating a
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Speaker 1: debris flow and flood that traveled around 62 miles. It's
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Speaker 1: just a gobsmackingly unbelievable amount of water, says Daniel Shugar,
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Speaker 1: geologist at the University of Calgary in Canada. Quote, figuring
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Speaker 1: out where that water came from is actually probably the
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Speaker 1: hardest thing about all this, end quote. Did climate change
19:17
Speaker 1: play a role? While no attribution study has been done yet,
19:22
Speaker 1: scientists already know that rising global temperatures caused by human
19:26
Speaker 1: activity are destabilizing glaciers in the Himalayas, which contain some
19:30
Speaker 1: of the world's tallest slopes. Quote, there's no question that
19:35
Speaker 1: this event was made more likely because of climate change
19:37
Speaker 1: and that we're seeing more likely other similar glacial hazards occurring,
19:43
Speaker 1: says Twyla Moon, glaciologist at the University of Colorado Boulder.
19:49
Speaker 1: Not only are thousands of glaciers losing ice at unprecedented rates,
19:54
Speaker 1: the permafrost they sit atop is also thawing. As that
19:58
Speaker 1: frozen blend of soil, rocks, and organic material warms, the
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Speaker 1: mountains and surrounding ice become less stable. In turn, this, quote,
20:09
Speaker 1: can result in massive landslides triggering a number of cascading
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Speaker 1: processes that can lead to a massive flood and destruction downstream,
20:19
Speaker 1: says Alton Byers, mountain geographer at the University of Colorado Boulder.
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Speaker 1: Scientists say events like this are probably going to become
20:27
Speaker 1: more common as the world continues to heat up. That's
20:31
Speaker 1: why Shashir Kanal, Nepal's Minister for Foreign Affairs, called for
20:35
Speaker 1: a global effort to address climate change during an August
20:39
Speaker 1: 29th press conference. Quote, we request the global community to
20:44
Speaker 1: come together and preserve the Himalayan ecosystem, he said. The
20:49
Speaker 1: country is one of the world's lowest contributors of planet-warming
20:52
Speaker 1: greenhouse gases, but it faces some of the worst impacts
20:55
Speaker 1: of climate change. Shugar echoes that sentiment perfectly.
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Speaker 2: To PBS News' Jeff Bennett, quote, we need to be
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Speaker 2: stepping up to help mitigate these risks and to enhance
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Speaker 2: the resiliency of people living in these environments that are
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Speaker 2: subject to these disasters.
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Speaker 1: When there's a climate change link, we in the rich
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Speaker 1: West are largely responsible for it, he says. What comes next?
21:22
Speaker 1: Rescue efforts are still underway and it will likely take
21:24
Speaker 1: weeks to recover all victims. That includes survivors who are
21:31
Speaker 1: stuck atop buildings that rescue teams are struggling to access
21:35
Speaker 1: and hundreds of workers who are trapped in hydropower tunnels.
21:40
Speaker 1: A months-long cleanup effort will follow and some people may
21:43
Speaker 1: never find their loved ones' bodies, which may have even
21:46
Speaker 1: been swept to India, reports The Guardian's Hannah Ellis Peterson.
21:52
Speaker 1: According to Reuters' Saruba Sharma, Nepali officials estimate that it
21:59
Speaker 1: will cost $ 4 to $ 5 billion, or about a tenth
22:03
Speaker 1: of the country's economy, to rebuild. Now, National Geographic has
22:11
Speaker 1: an article headlined, How Wildfire is Erasing the Forests of
22:15
Speaker 1: the American West. It's from August 31st. One summer evening
22:21
Speaker 1: in 1996, an abandoned campfire caught the woods of the
22:25
Speaker 1: Jemez Mountains in northern New Mexico. on fire. The next day,
22:31
Speaker 1: the wildfire exploded. The fire trapped 48 firefighters on a
22:36
Speaker 1: dirt road, forcing them to deploy their shelters, and flames
22:41
Speaker 1: advanced on the Los Alamos National Laboratory. Ultimately, the fire
22:46
Speaker 1: consumed an engine and burned the arms of a firefighter
22:49
Speaker 1: who lost his gloves, but it did not reach the lab.
22:53
Speaker 1: What surprised everyone in the aftermath was the number of
22:56
Speaker 1: dead trees. The Dome Fire burned at such an intensity
23:01
Speaker 1: across 6,600 acres, some 40% of its total path, that
23:07
Speaker 1: it killed swaths of mixed conifers and ponderosa pines that
23:12
Speaker 1: had survived centuries of fires. But this fire was hotter
23:16
Speaker 1: than the others. People said the trees would come back,
23:19
Speaker 1: no big deal, and indeed they started to. Then, in 2000,
23:23
Speaker 1: a larger fire, the Cerro Grande, ripped through the scar
23:28
Speaker 1: of the dome fire. Then, in 2011, a much larger fire,
23:32
Speaker 1: the Lost Conscious, ripped through the scars of both fires.
23:37
Speaker 1: Now 30 years have passed since the dome fire, but
23:39
Speaker 1: the trees have not come back. Ridgelines of the Jemez Mountains,
23:44
Speaker 1: once cloaked in green canopies, are now craggy, barren, and brown.
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Speaker 1: An emerging body of research is showing that those early fires,
23:52
Speaker 1: once novelties across the West, have become the norm. According
23:56
Speaker 1: to a paper published in late June in the Proceedings
23:59
Speaker 1: of the National Academy of Sciences, forest-eliminating wildfires are now
24:04
Speaker 1: the most common type of fire in California. Research published
24:08
Speaker 1: in the past few years suggests much of the West
24:11
Speaker 1: is following the same trend. In the last four decades,
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Speaker 1: largely because of wildfires, 9% of forests across the West
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Speaker 1: have died. While it is too soon to know the
24:22
Speaker 1: ecological fallout from the many fires burning this summer across
24:25
Speaker 1: the western U.S., research suggests that the damage may leave
24:29
Speaker 1: permanent scars. In the coming century, parts of the region
24:33
Speaker 1: will lose up to a third of its forests. To
24:37
Speaker 1: look for clues to how this will happen, look to
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Speaker 1: what's unfolding in the Jamez Mountains, scientists say. And what's
24:43
Speaker 1: happening there, they also say, is dire. Before we started
24:48
Speaker 1: putting them out in the 1880s, most of the wildfires
24:51
Speaker 1: out west were so-called good fires, crawling across the forest
24:56
Speaker 1: floor every 2 to 20 years, consuming logs and leaf
24:59
Speaker 1: litter and shrubs and grass. Fires maintained ecosystems. Today, they
25:06
Speaker 1: are just as likely to kill them. The high-severity fires
25:09
Speaker 1: seen more frequently today are the kinds of fires whose
25:12
Speaker 1: smoke crosses the continent to dim the sun in New
25:16
Speaker 1: York City. They dominate the land after 140 years of
25:19
Speaker 1: fire suppression policies and practices have largely banished good fires.
25:25
Speaker 1: As the West continues to heat up and dry out,
25:28
Speaker 1: the nearly century and a half of backlogged fuel in
25:31
Speaker 1: the forests are going up all at once. Quote, basically,
25:36
Speaker 1: as long as you have a bunch of fuels, then
25:38
Speaker 1: the drier climate is going to give you bigger fires,
25:41
Speaker 1: said Park Williams, a geography professor at the University of California,
25:45
Speaker 1: Los Angeles. and an author on the recent paper. Quote,
25:50
Speaker 1: it's easier to start fires and it's easier to spread fires,
25:54
Speaker 1: end quote. The Jemez Mountains are ground zero for this phenomenon.
26:02
Speaker 1: According to Andres Huion, the lead author on a paper
26:07
Speaker 1: published today explaining how fire is reshaping the mountains. He
26:12
Speaker 1: notes that scientists have studied this landscape's fire history more
26:16
Speaker 1: than anywhere else in North America. Wyan, a postdoctoral researcher
26:21
Speaker 1: at the New Mexico Forest and Watershed Restoration Institute, compares
26:25
Speaker 1: the process unfolding in the Jemez to a mouse eating cheese. Ultimately,
26:30
Speaker 1: his and his colleagues' research suggests the mouse will likely
26:35
Speaker 1: eat the entire wedge. By 2065, Wyand predicts fewer than
26:40
Speaker 1: half of the conifer forests of the Jemez will remain.
26:45
Speaker 1: By 2115, between 5 and 33% will remain. Quote, we
26:51
Speaker 1: will likely not have forests to pass on to our
26:55
Speaker 1: next generation if everything keeps burning the way it is
26:58
Speaker 1: burning and you just let it burn, he said. The
27:01
Speaker 1: forecasts are dire. It's just unsustainable, end quote. Many of
27:08
Speaker 1: these wildfires have more in common with bombs than they
27:11
Speaker 1: do natural processes. The kind of wildfire that most western
27:16
Speaker 1: forests evolved alongside spreads outward, its temperatures spiking highest along
27:21
Speaker 1: the leading edge as it consumes new fuel, stopping when
27:25
Speaker 1: it runs out of things to burn or is put
27:27
Speaker 1: out by rain or the absence of wind. But this
27:31
Speaker 1: more severe species of wildfire often sustains itself, feeding on
27:36
Speaker 1: fuels stockpiled in the forest By a century of fire exclusion,
27:41
Speaker 1: the fire concentrates heat at its center. Getting so hot,
27:45
Speaker 1: it sometimes creates its own weather. The pyrocumulonimbus clouds have
27:51
Speaker 1: been documented billowing 25,000 feet above these fires. These clouds
27:56
Speaker 1: release downdrafts that drive wind along the surface of the fire,
28:00
Speaker 1: blowing flames outward and killing everything in its path. Well,
28:06
Speaker 1: that's all for today's Diary of Science and Nature, your
28:09
Speaker 1: reader is Kelly Taylor. Now stay tuned for further programming
28:13
Speaker 1: on Radio Eye.