Wednesday, May 23, 2018

It's World Turtle Day! Honu, the Hawaiian Green Sea Turtle

It's World Turtle Day! That's nice because last May I paid a visit to the Hawaiian Islands and got these pictures and I've been looking for an excuse to post them somewhere. We saw the Hawaiian Green Sea Turtles (Chelonia mydas) while we toured the North Shore near Waimea. There's a fairly quiet stretch of beach where they like to pull up and rest. They spend the rest of their time feeding on sea grass and algae.
The Hawaiians called the turtle Honu, and it is held in high regard by the islanders. They were important animal spirits but also provided food and tools made from their shells. Their harvesting was carefully controlled by the local chiefs and the kapu system. The collision of Hawaiian culture with Europeans was a disaster in many, many ways, but it was especially bad for the turtles. They were harvested almost to extinction. Their survival was in doubt until they came under the protection of state and federal laws. Today they are a highlight of a visit to the islands

America Has Other Volcanoes: Airliner Chronicles Visits Mt. Hood

The tragic and yet fascinating activity on the Big Island of Hawai'i has focused attention on volcanism in the United States, and has served to remind us that Hawai'i isn't the only place in the country that has to face up to the hazards of living in the shadow of dangerous mountains. I traveled to Washington by plane last week and was lucky enough to capture images of several of the volcanoes of the Cascades. We looked at Mt. Rainier first, and then at California's largest yet little-known volcano, Medicine Lake Highland. I really wanted to show some shots of St. Helens but we flew right over it, so I cheated and used some shots from 2006. But I wasn't disappointed by Oregon. The face of Mt. Hood was still illuminated by the rapidly setting sun.
Mt. Hood is the headache for emergency planners in Portland and the small villages south of the Columbia River. It is the highest mountain in Oregon at 11,249 feet (3,429 meters). The upper slopes are extremely rugged and steep and as such present a serious threat of debris avalanches similar in nature to that which destroyed the summit of Mt. St. Helens in 1980. The scar of the most recent avalanche can be seen on the right side of the summit in the picture below. The slide took place about 1,500 years ago. The prominent spike of rock in the alcove is called Crater Rock, and it is the remains of a lava dome that erupted around 1781. An earlier avalanche around 100,000 years ago removed the north flank of the mountain and flowed down Hood River Valley and across the Columbia River.

The thick mantle of snow presents the other serious hazard, that of lahars, or volcanic mudflows. The fluid masses have reached the outskirts of Portland in the past, and some lahars have occurred in recent years even though no eruption took place.

Living near volcanoes doesn't and shouldn't mean living in constant fear, but it is important to be aware of the potential threats where you live, and an understanding of what you will need to do in the event of an eruption. And because of all the crap roiling around on the internet, get your information from the geologists who work for the U.S. Geological Survey or state surveys in your area. Always be aware of the potential of exaggeration in the media, because even if they present good information, it will be cloaked in clickbait-style headlines that they utilize to get attention these days.

Meanwhile, the plane continued southward, and another volcano or two could still be discerned in the fog and mist. My mention of the Airline Chronicles refers to my first blog series that started way back in 2008. Some more information on Mt. Hood is available at  https://pubs.usgs.gov/fs/2000/fs060-00/.

Friday, May 18, 2018

The Mount St. Helens Eruption at 38 years, and Why it Matters Today

I'd love to say I got these photographs of Mt. St. Helens last week when I flew to Seattle, but we flew right over the volcano, so you'll have to settle for the pictures I got on a flyover back in 2006. I did get pictures of Mt. Rainier and Medicine Lake Highland though. In any case, it is the 38th anniversary of the famed eruption of the volcano and as I think of those days, I realize some disturbing things.
When the volcano began rumbling and sending ash into the atmosphere, we had only a few avenues to get information, mainly television news, radio, and newspapers. I think now how limiting these sources were compared to the nearly instantaneous delivery of news over the internet in the present day. We can look up earthquakes just moments after they happen, and webcams allow us to monitor volcanoes around the world in real time. There is both good and bad in this profound change. There were terrible sources of news in those olden days, like the Weekly World News or the National Enquirer, but they pale in comparison to the sewage found on the internet today. Back then, national news outlets and newspapers practiced careful journalism in most instances, but it often seems today that the only reward for excellence and honesty in reporting is decreased ratings and falling revenues. To get attention in a crowded internet environment media outlets have to dress their stories in shiny objects and provide them with the worst possible clickbait titles. In the olden days we often had to wait impatiently for information about natural disasters, but the information that came through the media was more often vetted and checked for accuracy. The journalistic filters today are completely gone, and it can be difficult to distinguish between the trash and the truth.

There are so many conspiracy theories floating around today about natural disasters and potential disasters. The eruption of Steamboat Geyser in Yellowstone National Park five times in two months (after four years of quiescence) has caused a blizzard of posts on the internet pondering whether Yellowstone has been disturbed and may blow as a "supervolcano" eruption soon (and we'll all die). The same has happened after a number of recent small earthquakes. But a reading of the reality-based data says that Yellowstone caldera has not had a lava flow or eruption of any kind in 70,000 years, and no knowledgeable geologist sees any evidence of precursors to any new eruptions. A few years back, an earthquake and an internet video of a group of bison running "away" from Yellowstone caused the same kind of internet speculation (it turns out the bison were running towards the caldera).

Of course it is true that the Yellowstone caldera was born in one of the most colossal eruptions ever recorded. Learning the story of the eruption of the Huckleberry Tuff is fascinating. It brings an entirely new appreciation of the incredible scenery to be observed in a place that contains 70% of all the world's geysers. It should be enough. But there are so many individuals out there who would like to make a buck by scaring people needlessly. And there are too many gullible and ignorant people out there who can't pick rational accounts out of the confusing mix of conspiracy theories that exist on the internet.

And then there is the Big Island of Hawai'i. There are some serious things going on during the current phase of the eruption. The activity is endangering lives and destroying homes as Kilauea undergoes some major changes from the "norm" of the eruptions that have been ongoing for the last 35 years. The U.S. Geological Survey and Hawaiian civil defense authorities have been doing a pretty good job of providing up-to-date information about the latest activity, but that hasn't stopped all kinds of stories from popping up on the internet about the "Ring of Fire" which has nothing at all to do with Hawai'i. It is just too easy to pick up stories of eruptions in Alaska and Indonesia and think there is a pattern of increasing volcanism or earthquake activity (OMG, a magnitude 6 quake in the Kermadec Islands and an eruption at Mt. Cleveland in Alaska! It's a pattern and therefore Seattle will fall into the sea very soon!). The problem is one of perspective: if you sign up for earthquake notifications and volcano advisories from the USGS or other geologic research institutions, you would realize that these things happen all the time, and that a cluster of events is not unusual.
It's one thing to make up stories about normal volcanic activity to scare people. One can argue that they are ultimately harmless because the eruptions aren't actually taking place or hurting anyone. But there are real-world consequences of ignoring journalistic standards. Many of those who make their money with false headlines about such things will also traffic in climate change denial. When science becomes a matter of believing whatever one wishes, the very real problem of global warming becomes just another "scare" story, and the alarm bells being sounded by climate scientists become just more noise in an internet full of noise. But the real-world consequences are happening now, and action is needed to counteract the changes or to stop them. But it has become too easy to ignore the problem because it is so incremental and slow-acting. It just can't compete with the shiny baubles and clickbait on the web.
People in Hawai'i right now are largely trusting the geologists who have studied the volcanoes all their lives and are thus making the correct decisions about evacuating their homes. In the same way they trusted the seismologists when a tsunami threatened the islands in 2011 after the massive earthquake in Japan. No lives were lost when the tsunami hit because people had evacuated the low-lying areas. The wave surge was 8 feet deep in places and caused millions of dollars of damage. Many people could have been killed, but they accepted the authority of the scientists who predicted the timing and magnitude of the seismically induced waves.

And that's why the Mt. St. Helens eruption of 1980 matters today. Science and scientific expertise matters. Climate change is an even more profound danger to society than any earthquake or volcanic eruption. We need people to give climate scientists the same kind of respect they give geologists when volcanoes are rumbling and smoking. They are the ones to listen to, not the hucksters on the internet who are out to make a buck, or trying to protect those industries that make their profits off of producing greenhouse gases. We seem to talk little these days about integrity and striving for excellence, but scientific researchers are among those who still have those traits. There are always exceptions, but I would trust a scientist over a politician any day of the week (unless it is clear that the politician knows how to listen to a scientist).

There is a sign seen at some of the March For Science protests that have been happening for the last year and a half around the country: "At the start of every disaster movie there's a scientist being ignored". Unfortunately, it is too true in real life as well.

If you are searching for good updates on Hawai'i volcanic activity, check out the USGS Twitter account at https://twitter.com/USGSVolcanoes or on Facebook at https://www.facebook.com/USGSVolcanoes/

Thursday, May 17, 2018

Airliner Chronicles: Do You Know California's Biggest Volcano? You May Be Surprised at the Answer

The summit complex of Medicine Lake Highland, with Glass Mountain at the top, the Medicine flow center-left, and Medicine Lake at center-right.
It's a real problem for a geologist to be flying through cloud cover. One loses track of time and location so when an opening in the clouds occurs, one cannot know for sure where one is. I can pick out the essential geologic details a lot of the time, but without temporal or spatial context, I can't recognize even some of the most familiar places that I've visited many times. That's what happened last Thursday when I was flying to SeaTac. I lost sight of the ground only a few minutes out of Sacramento, and when the ground reappeared again, I was totally fooled by the scenes in these pictures. I thought I might be over Newberry Crater in Oregon, but I couldn't place Paulina Lake with the steep ridge that should have been to the right in the picture above. So I figured it must be some place in the Three Sisters area that I wasn't familiar with. But then I got home and looked at the pictures on the computer instead of the camera. I was wrong.
The Medicine Flow dates to about 2,000 years ago. It is composed of thick dacite lava flows. Frozen Medicine Lake is to the right.


It turns out I was flying right over the top of California's biggest volcano. Mt. Shasta is California's most prominent volcano, rising to 14,162 feet above sea level. It's the largest stratovolcano in the entire Cascades chain, with more bulk than even Mt. Rainier, which we looked at in our previous post.

[At this point there is a bit of uncomfortable shuffling in the back of the room as a few of the geologists look at each other and start mumbling something unintelligible.

"Ahem, is there something you would like to add to the discussion?" I say.

"But we've seen Mt. Shasta, and it looks nothing like that".

"And you would be right" I say, "but give me a chance to finish". They relent.]

But this isn't Mt. Shasta. It may be the tallest volcano in California, and it may be the biggest stratovolcano in the Cascades, but we are forty miles northeast of Shasta, looking at an entirely different kind of volcano. It's a shield volcano called Medicine Lake Highland. Although it is not even 8,000 feet high, it is much wider, with a total volume of around 130 cubic miles, compared to about 108 cubic miles for Mt. Shasta.

The view from the ground shows a gently sloping edifice covered by a variety of cinder cones and plug domes. Medicine Lake Highland (MLH)is shield-shaped like the giant volcanoes that make up the Hawaiian Islands, and is composed in large part of basalt, the fairly non-viscous lava that can flow for long distances before congealing. But MLH is different in some important ways. Some of the magma chambers beneath the volcano originate in the crust rather than the mantle (dacite or rhyolite), and the silica-rich lavas that erupt at the surface are sticky and barely flow at all.
MLH is an active volcano. There have been at least 17 eruptions in the last 11,000 years, and the Glass Mountain flow (below) erupted only about 850 years ago. There are areas of geothermal activity that have been proposed for energy development, but these have been rebuffed so far (thank goodness).
Glass Mountain at the top of Medicine Lake Highland. The flow dates to 850-900 years before present.

The top of the shield complex is a caldera (a sunken crater-like depression caused by the inward collapse of the top of the volcano). It is about the size of the Crater Lake Caldera, but is not nearly as rugged, as it is many thousands of years older and has been partially filled with subsequent lava flows. Medicine Lake sits within the caldera, but is not volcanic in origin. During the ice ages, glaciers scoured the summit area of MLH and left behind some impermeable clay deposits that prevent water from sinking into the ground (there are very few streams or rivers on the volcano, as it is highly porous; massive springs are found around the base of the volcano.).

One of America's most interesting national monuments is found on the north flank of MLH. Lava Beds National Monument preserves more than 75 miles of underground lava tubes, one of the highest concentrations of such caves in North America (and maybe in the world). The park also preserves the memory of the last stand of the Modoc people in their struggle against the U.S. military in the 1870s. They held out for months in the barren lava flows but were finally betrayed and captured. The Modoc people survive, but much of their cultural history was lost when they were banished to Oklahoma.

The clouds soon closed in again and I saw nothing more until we were over Washington.

Wednesday, May 16, 2018

Dear Washington State: All is Forgiven...The Airliner Chronicles Returns

The Pacific Northwest has this problem. It has two particular things in great abundance: trees and clouds. It also has volcanoes, but much of the time the first two obscure the latter. At Christmas I drove to the Seattle area and spent three days, and never laid eyes on Mt. Rainier, the gigantic stratovolcano that looms over the Puget Sound region. In the last week I had occasion to fly to the Seattle area, and being the month of May, I figured I had a pretty good chance of seeing some of the Cascade volcanoes. It started out pretty well as we left Sacramento, since I could see Lassen Peak off in the distance and then it disappeared. The clouds obscured the views all the way to Washington with the sole exception of a brief look at Mt. Adams, and the view below of Mt. Rainier.
Yeah, somewhere in there is the summit of Mt. Rainier.


That was okay. I had four days of walking and driving around Kent and Renton, and figured there would be a view once in awhile of the massive volcano. Nothing doing. There were tantalizing glimpses while driving around, but there were always trees in the way. Washington was disappointing me.
The flight home was scheduled to take off at 7:50PM so I figured there were too many things that would happen to either delay the flight until after sunset, or the clouds would be there again. But we boarded the plane on time and while taxiing down the runway I got the best ground-based picture of the mountain on the entire trip. It wasn't much, but it was something. 
And then we took off. It was hazy, and we took off towards the north and did a long turn towards the south, long enough to make me wonder if we were going to pass Rainier on the wrong side. But as the plane banked there was suddenly a very big mountain in the window, and Washington with all her trees and clouds were immediately forgiven. The mountain was stunning in the evening light.
Mt. Rainier from the runway at SeaTac.

At 14,411 feet, Mt. Rainier is the tallest volcano in Cascades Range, and is exceeded in volume only by Mt. Shasta in Northern California. It was once even higher, but glaciers have removed 1,000 feet of rock or more from the summit.  Because it is by far the tallest mountain in the Pacific Northwest it is completely covered by the largest mass of glacial ice in the lower 48 states, about a cubic mile (I read somewhere that it contains half of the all the glacial ice in the lower 48, but I can't find the source and would welcome any corrections from those who know such things). Aside from the "normal" threats that volcanoes might present to a given region (lava flows, ash flows, and that sort of thing), the snow makes the mountain far more dangerous. It's not hard to imagine why: any small eruption would melt a vast amount of ice, forming volcanic mudflows called lahars that are capable of flowing for many tens of miles, and threatening many of the cities along the southern part of the Puget Sound. The entire city of Tacoma is built on a mudflow that thundered down the mountain 5,000 years ago. The last major eruption occurred around a thousand years ago, although minor activity may have occurred several times in the 1800s. 

We flew south as the sun was sinking below the horizon and several other volcanoes appeared out of the gloom. Those pictures will come later. By way of explanation, the term "Airliner Chronicles" refers to the very first blog series I ever put together way back in 2008. One of my earliest posts in the series was also an evening shot of Rainier. By some strange convergence, that post received its first and only comment just two days ago!

Thursday, May 10, 2018

Just For the Fun of It: A Beaver on the Shores of Lake Washington

I got one of those childhood wishes at long last tonight. I've never seen a beaver up close. That might seem odd, given the time I spend on rivers all over the American West. But I've never had a chance to watch and photograph one.
I saw evidence of beavers along the Tuolumne River several months ago, but I have yet to see one of them. I'd love to say that I saw this one along my river, but I'm currently a long way from home. I saw this beaver along the shores of Lake Washington near Seattle.


The North American Beaver was once common across the American West until a mania for beavers pelt hats in Europe fueled a massacre that nearly drove them extinct. They are reclaiming much of their lost territory in recent years, including along the shores of Lake Washington, to the misery in some cases of owners of carefully landscaped villas along the lake shore.

If today's beavers are sometimes a nuisance, imagine what they were like during the Pleistocene. A species, Castoroides, once ranged across North America that was as much as seven feet long. They went extinct around 11,000 years ago.


The

The Sentinels of Yosemite Valley: Giving Them a Bit of Respect

Let's consider for a moment that this is anyplace else in the world. You look up and see a waterfall that is 1,920 feet high, falling in six major steps. In what place in the world would this not be a notable feature with a state or national park designation? In what place would there not be thousands of people visiting every day, snapping pictures and oohing and aahing?
There are no parking lots and viewpoint for this waterfall. As a rule people barely notice that it exists. If that seems astounding, then take this as evidence of the extraordinary nature of Yosemite Valley. 2,000 foot high waterfalls disappear into the scenery. The name of this particular one is Sentinel Falls.
I admit that part of the reason Sentinel Falls is not as celebrated as some is that it is seasonal, flowing principally in the spring season. It's usually dry by the beginning of summer when most tourists visit the valley. But when it is flowing, it is spectacular.
Sentinel Rock suffers the same kind of locational insignificance. In any other part of the world, a 3,000 foot high sheer cliff would elicit awe and wonder. In Yosemite Valley there are so many dramatic cliffs that Sentinel gets lost because people are trying to get a glimpse of Yosemite Falls on the north rim of the valley. Sentinel Rock and the adjacent Sentinel Falls are on the south side of Yosemite Valley, almost directly across from Yosemite Falls. Yosemite is the waterfall that catches their attention.
That's not to suggest that Yosemite Falls doesn't deserve the adulation it receives. The waterfall is 2,425 feet tall, somewhere around the fifth to seventh highest in the world. It always has more water than Sentinel does, and in many ways it is more dramatic. But when I was taking pictures of Sentinel last week in the rainstorm, I was the only person standing in my little corner of the floor of Yosemite Valley. I didn't have to share my moment with throngs of tourists all staring at the same feature and snapping the same pictures from the same angle. It was just me and a quiet moment in an often crowded and hectic place.