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20 Climate Questions Answered Quick responses to critics of climate change.

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1 20 Climate Questions Answered Quick responses to critics of climate change

2 Climate change science has critics Critics are ok. Critics are ok. Need reviews and fact checking. Need reviews and fact checking. Instinctive denial is not ok. Instinctive denial is not ok. The questions are fair, but much of the rhetoric is getting personal and/or ad hoc. The questions are fair, but much of the rhetoric is getting personal and/or ad hoc. My goal is to answer some of the critics more common questions. My goal is to answer some of the critics more common questions.

3 Simple answers Im going to give short simple answers. Im going to give short simple answers. These answers are backed by tens of thousands of studies by thousands of scientists from dozens of countries. These answers are backed by tens of thousands of studies by thousands of scientists from dozens of countries. Full references available, but two single excellent sources: Full references available, but two single excellent sources: The Rough Guide to Climate Change by Robert Henson, The Rough Guide to Climate Change by Robert Henson, IPCC Fourth Assessment Report (Intergovernmental Panel on Climate Change), IPCC Fourth Assessment Report (Intergovernmental Panel on Climate Change),

4 Who am I to answer these questions? Ive studied glaciers and their relationship to climate change since Ive studied glaciers and their relationship to climate change since Ive published many peer-reviewed scientific papers on this topic. Ive published many peer-reviewed scientific papers on this topic. My contributions have been primarily to the underlying math and physics. My contributions have been primarily to the underlying math and physics. I am one of thousands who have studied climate change in detail. I am one of thousands who have studied climate change in detail. I am by no means the biggest contributor. I am by no means the biggest contributor. But I do have an intimate knowledge of the details, particularly the physics. But I do have an intimate knowledge of the details, particularly the physics.

5 Climate change work in Alaska and Greenland

6 The basics Humans have released greenhouse gasses into the atmosphere. Humans have released greenhouse gasses into the atmosphere. Mostly in last 100 years. Mostly in last 100 years. Industrial revolution. Industrial revolution.

7 The most important gasses Relative importance of each gas.

8 Greenhouse gasses trap heat Sunlight comes in (yellow arrow). Sunlight comes in (yellow arrow). Light is absorbed by Earth. Light is absorbed by Earth. Earth warms and radiates heat (red arrows). Earth warms and radiates heat (red arrows). Too much (extra) heat is absorbed by greenhouse gasses and trapped (dark red arrows). Too much (extra) heat is absorbed by greenhouse gasses and trapped (dark red arrows). Extra radiates back from greenhouse gasses and is trapped! Warms the Earth. Escapes to space. Normally, there is a 1 to1 balance between incoming and escaping radiation. Greenhouse gas molecule.

9 Hows it work? Like my dog. Bear soaks in the sun and heats up. Bear soaks in the sun and heats up.

10 Bear reradiates heat Sunlight is converted to heat that is reradiated outwards. Sunlight is converted to heat that is reradiated outwards. Normally, achieves a nice doggy equilibrium of 38°C (101°F). Normally, achieves a nice doggy equilibrium of 38°C (101°F).

11 Sometimes surrounds himself with greenhouse gasses Heat trapped by methane and other gasses. Heat trapped by methane and other gasses. Bounces back off of the molecules. Bounces back off of the molecules. Cant cool off properly. Cant cool off properly.

12 Is this our future? Ok, so the analogy isnt perfect. Ok, so the analogy isnt perfect. But the following pictures of our future are real. But the following pictures of our future are real.

13 Heat causes sea level to rise When glaciers melt, the water goes into the ocean and causes sea level to rise. Heat also causes ocean water to expand (and sea level to rise). 1909, Toboggan Glacier 2000, Toboggan Glacier

14 Grinnell Glacier, Glacier National Park 1938 (photo T.J. Hileman) 1981 (photo Carl Key) 2005 (photo Blase Reardon)

15 Climate change summary Current data shows Current data shows –0.8°C (1.4°F) increase in temperature over last century. relative to average temp. relative to average temp. –Rapidly melting glaciers. –Rising sea level (20cm in last century). –Shifts in plant and animal distributions. Figure from IPCC, 2007, Summary for Policymakers. Figure from IPCC, 2007, Summary for Policymakers.

16 Climate change future Models project Models project 1.4° to 5.8°C increase by ° to 5.8°C increase by ~50cm of sea level rise by ~50cm of sea level rise by –and mass human migrations necessary from coasts 37% of all species headed toward extinction by % of all species headed toward extinction by Loss of fresh water. Loss of fresh water. –Panel of US Army generals (2007) have predicted resulting wars over food and water.

17 On to the questions! Ok, thats the crude basics. Ok, thats the crude basics. Now, on to the questions that Im frequently asked… Now, on to the questions that Im frequently asked… I hear them in the checkout line, on the chair lift, etc. I hear them in the checkout line, on the chair lift, etc. You might too. You might too. Heres how you can respond… Heres how you can respond…

18 You cant even predict the weather! Why should I believe 100 year predictions? I hear this a lot. I hear this a lot. Weather models as shown on the nightly TV news are getting more elaborate, but their accuracy is still not very good beyond a few hours or a few days at best. Predictions over decades are futile. Weather models as shown on the nightly TV news are getting more elaborate, but their accuracy is still not very good beyond a few hours or a few days at best. Predictions over decades are futile. From commentary in the Boulder Daily Camera, January 20, From commentary in the Boulder Daily Camera, January 20, 2008.

19 Why should I believe 100 year predictions? (Part 2) Weather and climate are NOT the same thing. Weather and climate are NOT the same thing. Climate is the average weather over long periods of time. Climate is the average weather over long periods of time. This lecture is in January in Colorado. Can you tell me if it will be warmer here in June? This lecture is in January in Colorado. Can you tell me if it will be warmer here in June? Duh! Thats climate. We can predict warmer weather in June with certainty. Duh! Thats climate. We can predict warmer weather in June with certainty. Predicting the average weather (climate) is possible (even though the day-to-day variations are harder to predict). Predicting the average weather (climate) is possible (even though the day-to-day variations are harder to predict).

20 Warming schmarming. It snowed sooo much this week, how can global warming be real? AKA: Its sooo cold this week, global warming must be a hoax. AKA: Its sooo cold this week, global warming must be a hoax. Again, thats weather not Again, thats weather notclimate. No single storm or cold snap No single storm or cold snap or hurricane can be directly attributed to climate change. We will still have winters. We will still have winters. We will still have extreme We will still have extreme weather events. My car buried in snow. Not proof that global warming is a hoax.

21 Humans couldnt do all that with puny little cars, could they? (Part 1) Yup. Yup. Data shows we have. Data shows we have. Cars, planes, industry, etc. Cars, planes, industry, etc. We spew ~26 billion metric tons of greenhouse gasses per year. We spew ~26 billion metric tons of greenhouse gasses per year. Thats the equivalent weight of 17 billion cars. Thats the equivalent weight of 17 billion cars. Thats enough cars to completely cover the surface of the Earth about 3000 times. It would take about 1000 years to count that high. It would take about 1000 years to count that high. Many different models from many different scientists show that these amounts cause climate change. Many different models from many different scientists show that these amounts cause climate change.

22 Humans couldnt do all that with puny little cars, could they? (Part 2) Wheres 26 billion metric tons go? Wheres 26 billion metric tons go? The Earth isnt as big as we used to think. The Earth isnt as big as we used to think. Its surrounded by a VERY thin atmosphere – like a sheet of paper on a basketball. Its surrounded by a VERY thin atmosphere – like a sheet of paper on a basketball. Not much room for all those warming gasses! Not much room for all those warming gasses!

23 Humans couldnt do all that with puny little cars, could they? (Part 3) Consider Mt. Pinatubo, Consider Mt. Pinatubo, One volcano spewed ~20 billion metric tons of cooling sulfur dioxide, ashes, etc. One volcano spewed ~20 billion metric tons of cooling sulfur dioxide, ashes, etc. One single volcano lowered temperatures by 1.0° C for several years. One single volcano lowered temperatures by 1.0° C for several years. But we spew more than that in warming gasses every year! But we spew more than that in warming gasses every year!

24 Scientists are perpetuating the myth to keep their funding, right? No. No. That requires belief in a global-scale conspiracy among thousands of climate change scientists AND the governments that fund them. That requires belief in a global-scale conspiracy among thousands of climate change scientists AND the governments that fund them. Would only take one credible scientists with credible results to speak up and ruin the conspiracy. Would only take one credible scientists with credible results to speak up and ruin the conspiracy. Occams razor – the conspiracy explanation is too complicated! Occams razor – the conspiracy explanation is too complicated! The core of the global warming research was completed when very little funding was available (1980s-1990s). The core of the global warming research was completed when very little funding was available (1980s-1990s). Personal viewpoint: Climate change funding was so hard to find in the 1990s that I decided to pick up a second skill set as a computer scientist. Personal viewpoint: Climate change funding was so hard to find in the 1990s that I decided to pick up a second skill set as a computer scientist. Sure, institutions self-perpetuate. Sure, institutions self-perpetuate. But scientists are trained to be skeptical. They want to debunk the current theory. Want to change the paradigm. (And make a lasting contribution.) But scientists are trained to be skeptical. They want to debunk the current theory. Want to change the paradigm. (And make a lasting contribution.) Scientists are not in it for the money. Scientists are not in it for the money.

25 No. No. Natural variability happens. Natural variability happens. Data shows that human Data shows that human changes are being added on to that natural variability. Very reliable models all show that only mankinds addition of greenhouse gasses can be responsible. Very reliable models all show that only mankinds addition of greenhouse gasses can be responsible. Natural variability alone cant account for observed warming. All the models agree on this! Natural variability alone cant account for observed warming. All the models agree on this! Isnt it just a natural cycle? (Part 1)

26 Isnt it just a natural cycle? (Part 2) This figure shows temperature data (black line) and climate models This figure shows temperature data (black line) and climate models –with only natural processes (in blue) –with both natural and man-made processes (in pink). Clearly, the models only match the data when including the man- made processes. Clearly, the models only match the data when including the man- made processes. From the IPCC 2007 Summary for Policymakers. From the IPCC 2007 Summary for Policymakers.

27 But I heard that variations in the sun cause the changes, right? Wrong. Wrong. Changes in solar output Changes in solar output have contributed about 1/3 of the warming over the last 100 years. The rest comes from The rest comes from greenhouse gasses. Very thorough modeling studies done by many different scientists back this up. Very thorough modeling studies done by many different scientists back this up. Sunspots affect solar output. (Photo: Bahr)

28 Isnt climate science filled with uncertainties? No, not really. No, not really. The foundations are very solid and based on reliable math, physics, and chemistry. The foundations are very solid and based on reliable math, physics, and chemistry. Virtually unanimous agreement among thousands of climate scientists that warming is happening. Virtually unanimous agreement among thousands of climate scientists that warming is happening. Most of the uncertainty comes from our inability to predict what people and governments will do in the future. Most of the uncertainty comes from our inability to predict what people and governments will do in the future. So we create scenarios. So we create scenarios. If governments let CO 2 double, then we expect this… If governments let CO 2 double, then we expect this… If CO 2 triples, then we expect this… If CO 2 triples, then we expect this… This creates a range of results. This creates a range of results. Remaining uncertainties are matters of precision. Remaining uncertainties are matters of precision. Will it rain more in your backyard or mine? Will it rain more in your backyard or mine? Exactly how much will it warm here versus there. Exactly how much will it warm here versus there.

29 Arent the models too complicated to be reliable? (Part 1) No. Complicated does not mean wrong. No. Complicated does not mean wrong. Your cars and TVs are very complicated. Your cars and TVs are very complicated. But they work just fine. But they work just fine. Do you think plasma TVs dont work? Do you think plasma TVs dont work? Much of the physics (thermodynamics) is the same! Much of the physics (thermodynamics) is the same! Not understanding the model is not the same as discrediting it. Not understanding the model is not the same as discrediting it.

30 Arent the models too complicated to be reliable? (Part 2) 14 different climate models running 56 different simulations. 14 different climate models running 56 different simulations. –All simulations shown in yellow. –The mean is in red. –The actual data is in black. Clearly, the models reliably simulate the data. Clearly, the models reliably simulate the data. From IPCC, 2007, The Physical Science Basis. From IPCC, 2007, The Physical Science Basis. Temperature anomalies shown relative to the mean.

31 Arent the models too complicated to be reliable? (Part 1) Complexity is often a relative statement. Complexity is often a relative statement. Want an example? See another of my lectures: Sea Level Rise and Glaciers. Want an example? See another of my lectures: Sea Level Rise and Glaciers.Sea Level Rise and GlaciersSea Level Rise and Glaciers I work through some of the math and physics used to help predict sea level rise. I work through some of the math and physics used to help predict sea level rise. To a freshman physics major, this material is complex. To a freshman physics major, this material is complex. To a senior physics major, this material is not so complex. To a senior physics major, this material is not so complex.

32 But arent some glaciers actually growing? So you must be wrong? AKA: The temperature gauge in the city of ____ shows cooling. So youre wrong. AKA: The temperature gauge in the city of ____ shows cooling. So youre wrong. AKA: I saw An Inconvenient Truth and Al Gore lied about point X. AKA: I saw An Inconvenient Truth and Al Gore lied about point X. Umm, no. This is called cherry picking. Umm, no. This is called cherry picking. You cant focus on one piece of contrary data when the tidal wave of evidence supports the opposite conclusion. You cant focus on one piece of contrary data when the tidal wave of evidence supports the opposite conclusion. Besides, we have predicted that some parts of the world will cool, get wetter, snow more, grow bigger glaciers, etc. Besides, we have predicted that some parts of the world will cool, get wetter, snow more, grow bigger glaciers, etc. Those predictions are consistent with a GLOBAL-scale trend of warming. Those predictions are consistent with a GLOBAL-scale trend of warming.

33 Cherry Picking What if I told you The average American is 57 tall. What if I told you The average American is 57 tall. Can you trot out Michael Jordan as a contradiction? Can you trot out Michael Jordan as a contradiction? Duh. No. Duh. No.

34 Isnt the hockey-stick curve based on bad science? (Part 1) AKA: The hockey stick is wrong because ______. AKA: The hockey stick is wrong because ______. From Mann et al, 1998, 1999, etc.

35 Isnt the hockey-stick curve based on bad science? (Part 2) No. No. This figure has been peer-reviewed by independent scientists many, many times. This figure has been peer-reviewed by independent scientists many, many times. Its conclusions are always supported. Its conclusions are always supported. Scores of scientists contributed to the data in this figure. Scores of scientists contributed to the data in this figure. i.e., it is not a fabrication of Michael Mann or Al Gore. i.e., it is not a fabrication of Michael Mann or Al Gore. Global warming does not rely on just this one piece of (very strong) evidence. Global warming does not rely on just this one piece of (very strong) evidence. Can you say cherry picking? Can you say cherry picking?

36 Scientists have been wrong before. Why trust them now? AKA: What about global cooling predicted in the 1970s? AKA: What about global cooling predicted in the 1970s? That was not a scientific consensus. That was not a scientific consensus. Only briefly considered by a small minority of scientists. Only briefly considered by a small minority of scientists. Media latched onto this more than scientists. Media latched onto this more than scientists. In part, fueled by concerns about a nuclear winter. In part, fueled by concerns about a nuclear winter. Also see next slide. Also see next slide.

37 Many scientists disagree, so why should I believe? (Part 1) Umm, which scientists? Where? Umm, which scientists? Where? Global warming is a scientific consensus! Global warming is a scientific consensus! It is very hard to find climate scientists that disagree. It is very hard to find climate scientists that disagree. Out of thousands, you might find 2 or 3. Out of thousands, you might find 2 or 3. Check their credentials carefully. Check their credentials carefully. Have they published and done first hand research in climate change? Or did they just review the literature? Have they published and done first hand research in climate change? Or did they just review the literature? Out of thousands, I can find a few people that believe in anything. Out of thousands, I can find a few people that believe in anything. 998 believe Im human. 2 believe Im a mutant alien. 998 believe Im human. 2 believe Im a mutant alien. I am not discrediting the critics intelligence, but its a tidal wave of support among the thousands that do this research. I am not discrediting the critics intelligence, but its a tidal wave of support among the thousands that do this research.

38 Many scientists disagree, so why should I believe? (Part 2) Some of this is the medias fault. Some of this is the medias fault. The media wants to present both points of view. The media wants to present both points of view. The media successfully uses this The media successfully uses this debate model with politics. So media searches out the few So media searches out the few critics and gives them equal footing and equal time. This gives the wrong impression that the critics and the climate scientists are equal in numbers. This gives the wrong impression that the critics and the climate scientists are equal in numbers. Or somehow equally right. Or somehow equally right.

39 But I read Michael Crichton and he says… AKA: I heard Senator Inhofe [or insert your choice here], and he says… AKA: I heard Senator Inhofe [or insert your choice here], and he says… Well, you can choose between thousands of climate scientists, or a science fiction writer… Well, you can choose between thousands of climate scientists, or a science fiction writer… Oh, and now youll believe politicians? Oh, and now youll believe politicians? Check those credentials! Check those credentials!

40 Couldnt something undiscovered be to blame? Yes, but physics says that greenhouse gasses cause warming. Yes, but physics says that greenhouse gasses cause warming. Now have the MUCH harder problem of explaining why modern physics is all wrong. Now have the MUCH harder problem of explaining why modern physics is all wrong. Oh, and broken thermodynamics means Oh, and broken thermodynamics means your car, computer, and plasma TVs wouldnt work anymore. Rats. Rats. Occams razor, again. Occams razor, again.

41 Who cares? Isnt a 1° to 2°C temperature increase insignificant? No! No! Every 1°C rise in temperature requires a 25% increase in snowfall to keep glaciers from melting. Every 1°C rise in temperature requires a 25% increase in snowfall to keep glaciers from melting. –So glaciers melt, sea level rises. –Ocean water also expands in that heat. Coastal aquifers inundated – no water to drink! Coastal aquifers inundated – no water to drink! Coastal cities inundated. Coastal cities inundated. People must migrate inland. People must migrate inland. Ports must be moved. Ports must be moved. Huge economic costs. Huge economic costs. Species go extinct. Species go extinct. Agriculture disrupted. Agriculture disrupted. Etc. Etc.

42 Wouldnt global warming be a good thing anyway? Define good and bad. Define good and bad. Thats a judgment call. Thats a judgment call. But ask the billions that live on the coast. But ask the billions that live on the coast. 11 of 15 of the worlds largest cities are at sea level. 11 of 15 of the worlds largest cities are at sea level. 53% of the US population lives on the coast. 53% of the US population lives on the coast. Climate change will be similar to El Niño. Climate change will be similar to El Niño. Massive flooding, droughts, famines, fires, storm surges, etc. accompany every El Niño. Massive flooding, droughts, famines, fires, storm surges, etc. accompany every El Niño. Is that good? Is that good? Try asking the polar bears. Or coral reefs. Try asking the polar bears. Or coral reefs. Or tropical beaches. Photo from National Geographic.

43 Wont technology come to the rescue? Well, I hope. Well, I hope. But you are placing a lot of faith in possible solutions that might or might not exist. But you are placing a lot of faith in possible solutions that might or might not exist. Some possible solutions (like spreading ash in the atmosphere) could cause a host of other problems. Some possible solutions (like spreading ash in the atmosphere) could cause a host of other problems. Isnt it wiser to mitigate the problem in the first place? Isnt it wiser to mitigate the problem in the first place?

44 Any mitigation will wreck the economy. You dont want that do you? (Part 1) Wreck the economy? Says who? Wreck the economy? Says who? Get their evidence. Get their evidence. Check their credentials! Check their credentials! Caveat: Im not an economist. Caveat: Im not an economist. See! Always check those credentials! See! Always check those credentials! But I do know there are two possibilities: But I do know there are two possibilities: Maybe we will wreck the economy. Maybe we will wreck the economy. Maybe we wont wreck the economy. Maybe we wont wreck the economy. (Continued next slide.)

45 Any mitigation will wreck the economy. You dont want that do you? (Part 2) Maybe we dont wreck the economy. Maybe we dont wreck the economy. Many green solutions like recycling have produced major cost savings. Many green solutions like recycling have produced major cost savings. Some economists project a green-industry boom. Some economists project a green-industry boom. Maybe we do wreck the economy. Maybe we do wreck the economy. Im not sure it matters. Im not sure it matters. Dont we have a moral obligation? Dont we have a moral obligation? Is a dent in the economy worth saving lives? Is a dent in the economy worth saving lives? Saving entire species? Saving entire species?

46 Any mitigation will wreck the economy. You dont want that do you? (Part 3) Either way, reacting to climate problems after the fact could be hugely expensive. Either way, reacting to climate problems after the fact could be hugely expensive. Whos going to pay to move entire cities? Whos going to pay to move entire cities? Whos going to pay for resulting wars? Whos going to pay for resulting wars? –Global climate change presents a serious national security threat that could affect Americans at home, impact U.S. military operations, and heighten global tensions. –Massive migrations, increased border tensions, greater demands for rescue and evacuation efforts, and conflicts over essential resources, including food and water – such developments could lead to direct U.S. military involvement. From US Military Advisory Board, 11 most-senior retired generals and admirals. From US Military Advisory Board, 11 most-senior retired generals and admirals. Isnt prevention the wisest choice? Isnt prevention the wisest choice?

47 Ok, its real, but isnt the response just mass hysteria? (Part 1) Thats a judgment call. Thats a judgment call. At what level is the response At what level is the responseover-the-top? To some extent, it is the To some extent, it is the FOX News syndrome. Death and destruction makes better Death and destruction makes betterpress. And its easy to turn global warming And its easy to turn global warming into pictures of dying polar bears. See? But wait, the polar bears are dying! But wait, the polar bears are dying! In my opinion the press coverage In my opinion the press coverage is warranted! Am I hysterical? Judgment call. Am I hysterical? Judgment call.

48 Ok, its real, but isnt the response just mass hysteria? (Part 2) Scientists have warned of other big baddies – nuclear winter, pesticide use, etc. Scientists have warned of other big baddies – nuclear winter, pesticide use, etc. And we have become immune to warnings about the end of the world. And we have become immune to warnings about the end of the world. But, this is the first time in history that a group of scientists have so concertedly, uniformly, and relentlessly sought to inform the public about an impending danger. But, this is the first time in history that a group of scientists have so concertedly, uniformly, and relentlessly sought to inform the public about an impending danger. Climate scientists feel a moral obligation. Climate scientists feel a moral obligation. Maybe that should scare us a little bit. Maybe that should scare us a little bit. The scientists say we have to do something now. The scientists say we have to do something now. Inaction will cost lives and dollars. Inaction will cost lives and dollars. Our moral obligation to help is not hysteria. Our moral obligation to help is not hysteria.

49 But I hate Al Gore. AKA: I really dislike _________. This person is polarizing. AKA: I really dislike _________. This person is polarizing. Strong words. Too bad. Als right. Strong words. Too bad. Als right. This is not a debate about personalities. This is not a debate about personalities.

50 Not a debate about personalities BTW, recognize that incorrect assumption that weather is the same as climate?

51 In fact, not a debate at all. Questions are productive and instructive! Questions are productive and instructive! But thats different from a debate. But thats different from a debate. The scientific consensus is overwhelming. The scientific consensus is overwhelming. Would you debate that the Earth is round? Would you debate that the Earth is round? And actions are most productive of all. And actions are most productive of all. Which brings me to the last question… Which brings me to the last question…

52 Yeah, well, theres nothing I can do, so why worry? But you can do something! But you can do something! Small actions by everyone add up to big contributions. Small actions by everyone add up to big contributions. Small actions by everyone added up to cause the problem in the first place! Small actions by everyone added up to cause the problem in the first place!

53 Things you can do! Small actions. Small actions. Doesnt have to be inordinately painful. Doesnt have to be inordinately painful. Reduce the miles you drive each week. Reduce the miles you drive each week. Drive slower (more fuel efficient). Drive slower (more fuel efficient). Vacation closer to home. Vacation closer to home. Use more energy efficient appliances, Use more energy efficient appliances, light bulbs, etc. Buy wind power (or solar, or…). Buy wind power (or solar, or…). Recycle. Recycle. Insulate your home and hot water heater. Insulate your home and hot water heater. Use low-flow shower heads. Use low-flow shower heads. Turn off computers at night. Turn off computers at night. Search the web for more ideas! Search the web for more ideas! Did you notice that most of these will save you $$? Did you notice that most of these will save you $$?

54 Mass hysteria summary Dont be that guy! Be the person that saves that guy, and this guy! Remember, 37% of all species headed toward extinction by 2050.

55 SAVE THIS! Most tropical beaches will be damaged or lost.

56 And this! ° Remember, no more coral reefs with 1°C rise.

57 And mitigate this Whitechuck Glacier, WA, USA 2006


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