What A Disappearing Yosemite Glacier Tells Us About Climate Change

Speaker 1: 00:00 This is KPBS mid day edition. I'm Maureen Cavenaugh and I'm jade Hindman. Even longtime residents might be surprised to learn of modern day glaciers in California, but the fact is remanence of the [inaudible] glacier in Yosemite national park or about to disappear glaciers sculpted Yosemite, spectacular granite monoliths, and it's waterfall Laden valley. Their demise tells us much about our changing world. KPBS is Mark Sauer brings us this interview with reporter Daniel Dwayne. He wrote about Yosemite's disappearing glaciers, this month's lead story in the California Sunday magazine. Now today. Daniel, welcome. Speaker 2: 00:36 Welcome to midday addition. Thanks for having me. Where you focused on the Lyle glacier, which forum quite recently. Tell us where it is and how it was formed and who discovered it. Well, okay, so the Lyell glacier sits on the flanks of the tallest peak in Yosemite national park, which is mount loyal. It was formed by the way, glacier certain, you know, all form more or less by the accumulation of snow over time, during what was known as the little ice age, an unusual cold snap that prevailed on earth from about the year 1300 1850 and it was first identified as a glacier by the naturalist John Muir in 1872. And how recently could hikers in Lyle Canyon come upon a fairly significant glacier there. In other words, what's left now compared with say 30 or more years ago when John Muir first identified this thing as a glacier, it was about 13 million square feet. Speaker 2: 01:31 Today the remnant ice field is three is 3 million square feet. So there's still a fairly big ice field up there. You can still hike up and look at it and see the melting out remnants. But um, you know, as, yeah, as recently as 30 or 40 years ago, a hiker up into that part of the high country would have seen quite a large and still moving, um, active glacier. The remnants of it, I mean, you, you're describing the story. You can, I guess a subjectively or make the call on this, but the glacier may actually be gone or dead or just remnants left. No, right. Yeah. So the, you know, the, the definition of a glacier includes downhill movement. So glaciers accumulate snow up high in there, you know, in the higher they're higher reaches, convert that snow slowly over time into ice. And then ice has a certain, almost kind of a viscosity, um, under the pressure of gravity that draws, it's slowly down in a kind of creeping molasses like riverine movement. Speaker 2: 02:33 That movement is what defines a glacier and separates it from a mirror ice field. The Lyle had that movement for quite a long time. What's it like being on what's left of loyal glacier in? If you didn't know that it was melting out, I think it would feel quite beautiful at that. You know, your viewer at almost 13,000 feet on this rocky remote mountain side that's quite steep and there's, this still feels like quite a big ice field. I think it covers about 60 acres perched on this slope. And when you walk up on it, the sun has created these melt features in it that are sort of fascinating. There are bath, tub size depressions all over the thing, um, and the sun beating on it. Um, you know, Mel is melting surface water and that surface water is pooling in those bathtub's size depressions and filling them up and flowing over the edges and down to the next and the next. Speaker 2: 03:27 So that it's like being, you know, if when you walk up onto it, it's like being a midst a thousand tiny little streams of perfectly pristine ice melt water that you could just lap up with your tongue. It's that clean. Um, and there's this sound of trickling in Gurgling of a million little clean creeks and there are sort of finer melt features just beneath the surface that are more like sort of arteries of water are capillaries of water. Um, so there's this beautiful white noise, watery gurgling sound everywhere up in the iron mountain sky there. And that sound is so soothing to the human ear, you know, that we buy white noise machines that produce it for us. It puts his to sleep and puts us, you know, at ease. Right? And so there's, there's something kind of confusing about hearing that sound, you know, and knowing that it's the sound of a, of the death of this thing and that every drop of water is one less drop of ice. Speaker 2: 04:29 Um, sustaining it. Roy, reading your story, I'm struck that a, the glaciers are almost kind of time machines. And then what do they tell us about the rapidly changing climate? I mean, one thing they tell us is that our climate is changing really, really fast. Another thing that the Lyle tells us is that he or suggests is that we humans have been disrupting the earth's climate for somewhat longer than we've realized that there are fluctuations in the earth's climate back for several hundred. You know, even a few thousand years that may have had to do with the rise of human agriculture with this little ice age that I mentioned was this very peculiar abrupt cooling period that started oddly about the time of the black death in Europe when the bubonic plague wiped out about a third of the population of Europe and cratered agriculture and allowed to sort of reforestation that would have taken carbon out of the atmosphere. Speaker 2: 05:27 It seems to have been worsened by the deaths of 50 plus million indigenous people in the new world as a result of disease brought by Europeans to the new world, thus more cratering of agriculture, more reforestation, and then at the little ice age sort of flipped ended. And are the climate flipped toward runaway warming. Curiously, between about 1850 in 1900 as the industrial revolution took off and the atmosphere began to fill again, carbon, the birth life and very abrupt death of the lions are all sort of a story of, um, the ways in which we are changing the atmosphere that supports us in rather dramatic ways. Without conscious plan. I've been speaking with writer Daniel Dwayne, his story, what remains, describes the rise and fall of Lyell glacier in Yosemite national park. Thanks, Daniel. Thank you.