Archive | March 2019

Does Madame Pele Like Geothermal Energy?

Hawaii lore is full of stories about trying to get lava flows to stop.  The US Army Air Corps tried bombing flows, Princess Ruth was credited in 1881 with saving Hilo from a flow, the Mauna Loa observatory high on the volcano comes with levees built to deflect lava flows. Perhaps another chapter was written within the devastating eruption of 2018….

GG had the good fortune to visit Hawaii recently and of course had to check out the flows from the 2018 eruption.  One spot visited was near the Puna Geothermal Venture (PGV), a geothermal energy plant run by global geothermal company Ormat Technologies that supplied about 25% of the Big Island’s electricity before being shut down as the 2018 eruption intensified. There were a few surprises.

First, though, what is remarkable is that there is a plant to discuss at all.  The location of the plant was chosen for proximity to magma–indeed, one of the wells drilled actually tapped magma directly (not ideal for geothermal work). When the fissure system of the Lower Puna eruption began in May of 2018, the plant (placed on a 1955 flow adjacent to the cinder cone of Puu Honuaula) began capping wells and draining the fluid used in the closed-system geothermal heat exchangers. Initially it probably seemed as though this would prove unnecessary as the initial long flows starting on 19 May from the eruption headed south, away from the plant.

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Those flows went south to the ocean, but late on May 25th flows began descending the north side of the East Rift Zone, emanating from fissure 8 and heading toward the geothermal plant. It seemed quite possible that the plant would be obliterated as lava encroached on the plant’s land. Soon thereafter a warehouse with a drilling rig and a substation were lost to the advancing lava; three of the production wells were covered.

But on May 29th the flows shifted to the north, cutting the access roads to the geothermal plant but bypassing the main facilities of the plant. With the main lava flow channel becoming well established on that north side, the plant looked like it might survive.

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The main plant at Puna Geothermal Venture caught between the original fissure system (at bottom) and the main lava flow channel (at top). Blue Hawaiian Helicopter’s June 2, 2018 photo via the Honolulu Star Advertiser.

If you drive down to  Lava Trees State Park and go past the turn a few hundred feet, you find the western corner of PGV’s land, from where you might think the plant doomed.  Lava more that 60 feet thick lays across the roads that used to access the plant. Indeed, the top of the lava levees is about the same elevation as the main plant itself.

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View down the Pahoa-Pohoiki Road at western edge of PGV land, 3/29/19.

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View southwest from the same spot up the lava channel to the spatter cone of fissure 8, the main source of lava in the 2019 eruption. Note the downed power lines .

And yet, when all seemed to be said and done, although more than half the land of the Puna Geothermal Venture was under new lava, the main plant had survived. However, estimates in the media suggested it would be years before the plant could be reopened; indeed, it seemed possible that local opposition might shut the plant down permanently.

So GG was a bit surprised to first see ATVs and pickups going up and down over the flow and then hear from a local who stations himself near the road closures that the plant was about to fire up its generators again shortly–in latest March or April 2019, only a few months after molten rock blocked access to the plant.  Indeed, those ATVs and pickups were traversing the initial access road that was cut in December 2018, well before the usual six month waiting period for cutting roads across new flows. And checking the local news, indeed it seemed that the geothermal plant was going to be back in operation sooner rather than later with the bonus that the water temperatures are now hotter than before; instead of 2-3 years as originally feared, the plant’s operators plan to produce electricity within 16 months of the end of the eruption.

When the geothermal plant west down, the island was forced to restart older diesel generators to cover for the power loss.  The state is committed to renewable energy, so retreating to diesel was rather embarrassing, which generally strengthened the hands of alternative energy project advocates. But virtually all renewables generate their share of opposition; GG encountered flyers opposing a new wood-chip (biofuel) plant that touted solar and wind energy, but placement of wind turbines and solar farms have met opposition in some of those places. The geothermal plant, too, has faced opposition ranging from religious objections to the plant’s failure to control emissions of hydrogen sulfide from time to time. If there is to be power, somebody’s ox gets gored, it seems.

The 2018 eruption was close to the worst case scenario for PGV with active fissures of the East Rift Zone emerging only a few hundred meters from the plant. The choice of the elevated land near the old cinder cones was crucial in allowing the plant to survive, but certainly it was possible that Madame Pele could have opened the rift a bit to the north, swallowing up the power plant. So just maybe she approves of this use of her fires.

Petty Thoughts part 2…

GG’s travels ended with a road trip.  And the first thought is, somebody should start doing some serious roadwork. There was a bridge on a toll road that was more patches than original road surface. There were places where unavoidable potholes and associated patches made it across the entire lane. Having the suspension go “bang…bang…bang” was a far-too-common occurrence. Although we can hope that gas-powered cars will be on their way out, odds are awfully good that we’ll still be needing roads for quite some time to come.

Roadsign

Of course if you travel roads, you read road signs.  The one trolling the most was the electronic road sign in Illinois (above) asking you to quit taking pictures of the road sign (and yes, the passenger took the photo; sign didn’t say to not take a picture while being driven).

GG is always fascinated by how ambiguous many road signs really are, largely due to the absence of punctuation  (“Slow Children at Play” is a longtime classic in that regard). A new one was in New York, where a service area had on the exit sign a small blue sign saying “Text Stop”. We puzzled over this advice for awhile, trying to decide if we were to text the word “stop” to somebody (maybe the highway patrol), or ungrammatical advice that we stop texting, or being informed that this was a place to stop and text (so could we stop and not text?). It turns out that other signs are indeed advising people to not text while on the roadway but save it for a “text stop” like the service area or rest area.

(We also noticed rest areas are going away; there are a number that have been fully decommissioned but are still recognizable as rest areas from the past.  Are people’s bladders getting bigger?).

Anyways, just random stuff….

Stepping Down Waterfalls…

It is a rather rare thing when a rather pedestrian-seeming experimental geomorphology paper makes it to the New York Times, but that is the case with a recent study showing that waterfalls can be generated without any special events, like a change in climate or tectonic uplift. Quotes in the Times article indicate that this might require reevaluation of histories of areas that were defined by waterfalls.

Now GG is not a geomorphologist but he does pay some attention to that literature, and it isn’t so much waterfalls that have been dictating interpretations over the past few decades in places he cares about (western U.S.), but there is work that depends on the grade of rivers relative to drainage area (and rainfall and bedrock competence); are these impacted by this?

There is a hint near the end of the Nature article suggesting that the answer could be yes:

In the Big Tujunga Creek catchment, California, USA, many tributaries, such as Fox Creek (Fig. 1c), have a knickzone that has been linked to an increase in uplift rate3. Each knickzone is composed of numerous waterfalls that lack known origins, are consistent with autogenic formation, and have probably changed erosion rates of the broader knickzone in a manner that is inconsistent with fluvial incision models. [GG bolding]

Now if all that was happening was that rivers of a certain grade developed a sort of ramp-flat (waterfall-flat) geometry without changing the overall grade, current styles of interpretation probably would remain robust.  But if the development of this style of “self-formed” waterfalls messes with that, then all bets are off for streams with such features. And that includes virtually all of the rivers and streams in the Sierra…

GG kind of wonders how this compares with Clyde Wahrhaftig’s old hypothesis of stepped topography originating from variable bedrock erosion of granite.  By stepped topography, he meant the repetition of steep bare granite slopes alternating with vegetated flats as one moved up the west side of the Sierra Nevada. In that hypothesis, the lip of the steep slopes (where the waterfalls are) should have a low erosion rate while the flats near the base of falls should have higher rates.  In essence, the exposed bedrock created local knick points that did not move downward much while the upstream areas were eroding to match that elevation. But recent work from Jessup et al (2011), who measured erosion rates with cosmogenic isotopes, found “the pattern of erosion rates is one in which steps erode more quickly than treads, in direct contradiction to Wahrhaftig’s (1965) hypothesis.” But this is precisely the pattern seen in the new experimental work: the flats at the base of the waterfalls stop eroding once a plunge pool gets deep enough that the falling water doesn’t have any erosive power, while the lip of the waterfall gradually erodes down, eventually erasing the waterfall over some thousands of years. The flat acts as the knickpoint, not the top of the fall. 

While an interesting speculation, at this moment the notion that autogenic waterfalls explains the stepped topography of the Sierra deserves a shaker full of salt.  First, the scale of stepped topography is about an order of magnitude larger than the kinds of self-generating waterfalls discussed in the latest work. Second, stepped topography extends well away from the modern stream courses, something the new experimental work does not explore at all. Thus there are serious issues that would need to be solved before this could move beyond speculation. But while the new waterfall work might complicate the current style of landscape evolution analysis, it might also hold a clue to solving a more cryptic landscape puzzle.

Rank Rankings

We’re number one according to US News and World Report! We in this case being Geosciences at the University of Colorado Boulder. Woohoo! Time for a press release!

We’re tied for number 19 by US News and World Report!? How did that happen? What does it all MEAN?

In light of the college admissions scandal unfolding, let’s be clear: these mean nothing. And to learn why, just a brief reminder of what these really are.

CU is number one as a university because it publishes a lot of earth science papers that get cited a lot. This has nothing whatsoever to do with undergraduate education and arguably is not a very solid predictor of a great graduate program.  It reflects a large and productive research program (the numbers are not normalized by numbers of scientists).

CU’s Geological Sciences Department is number 19 because the rankings are a pure beauty contest from rankings from “surveys sent to academics.” These are always skewed towards programs that, ahem, have in the past generated academics now in a position to receive a survey (in the past, these were department chairs).  How often do you think a successful academic will dis their alma mater? Even vaguer is what precisely the basis for the evaluation is.  Research? Teaching? Groundskeeping? Collaborators? And CU suffers because a lot of earth science is not in this department.

How do either of these help you choose where to go to school? Simple: they don’t. For undergraduate work they are totally irrelevant.  For graduate work, barely relevant. Probably the one evaluation for grad schools that would be most useful is now getting seriously out of date, an NRC report put out in 2012 that among other things actually asked questions about student environment and outcome.

Given the rather transparent limitations of these prominent rankings, it stands to reason that the similar rankings of undergraduate schools is equally misleading. Schools bend rules to make things look better.  US News, for instance, counts classes as small if there are fewer than 20 students in them.  Magically, the limit for a bunch of courses descends from 25 or 30 to 19.

There are differences between graduate programs, but it often comes down to the thesis advisor, access to tools for completing degree work, and the peer group of students one could interact with. None of these are in any rankings; you have to do it yourself.

War on Science: Ostrich Edition

A disaster has befallen a major city.  Scientists offer to shift planned research to help understand the extent of the disaster and perhaps help guide remedial efforts with more concrete information. You head a government agency asked to allow this scientific research.  What do you say?

If you work in the current administration, you say “no.”

The particulars, as outlined in a Los Angeles Times story, are that NASA was getting ready to run a calibration flight of a pollution-sensing aircraft as floods hit Houston. The scientists were eager to shift from their original test flight to a flight over Houston, but somehow the EPA as asked if this was OK. They said thanks but no thanks, we have this with a few ground crews. NASA higher ups decided not to cross the EPA and so the flight never happened.

Nobody knows what might have turned up–maybe nothing.  Maybe major pollution sources that were unrecognized on the ground. But why not do this? Frankly, it is hard to see the answer being anything but “what we don’t know we can’t penalize or correct,” and the most likely folks facing penalties or corrective action would be in the oil and gas and chemical industries.  After all, if there were no measurements of, say, a release of volatilized hydrochloric acid, then residents who had developed nasty respiratory symptoms would probably be unable to sue responsible companies.

The Times piece has inspired a Congressional inquiry, but that will mainly be a game of seeing whose ass was least covered. The mindset of “the less we know, the better” is foolish and dangerous. And, down the road, the backlash might be far more damaging, as the oil and gas industry in Colorado has been learning. Faced with community opposition to some development plans, industry has largely followed a policy of opposing any intrusion on their plans. They are now faced with a bill in the Colorado Legislature that would give local governments the ability to limit drilling, would increase forced pooling requirements from a single mineral rights holder to 50% of those holding rights, would require public disclosure of where critical infrastructure is, and would require pressure testing of abandoned lines. While the fate of this bill is uncertain, that it has reached the floor of the state senate is a major step up from the past when similar legislation never got a hearing.

Each time industry tries to cover its failures, that Green New Deal currently being vilified gets a bit closer to being something Americans will come to demand. Opponents might want to defang such desires by behaving as though they care about knowing the risks citizens face both day-to-day and during disasters; asking for less information is not that behavior.

Petty Thoughts…

GG is traveling.  Today was by air and GG was reminded of a trick the airlines play on us that started some years back.  That is, the “departure time”.  As anybody who has travelled on an US flight knows, arriving at the departure time will allow you to wave at the plane that is already pulling back or even is starting down the runway.  The airlines hide this truth behind a warning the the doors will close 10 minutes before departure–but doesn’t that then kind of count as “departure”?  Why do we have to do this mental math? GG’s flight today left 6 minutes before departure.  Was there anybody arguing with the gate agent while we blissfully pulled back?

Something like the same trick occurs at the arriving airport.  On a flight that doesn’t have mechanical issues and doesn’t encounter unusual weather, the stated arrival time is (in GG’s experience) always 10-30 minutes later than the actual, “normal” arrival time and GG has seen flights arrive a solid hour early. If you don’t pay attention when you go to pick up a visitor, you can discover they’ve been cooling their heels for quite some time while you were arriving when the airline said the plane would.

Many of you are saying “Well, duh.  Airlines get penalized for late flights so they play the game of having the flight leave before it is supposed to on a route that should take significantly less time than is allowed.” Yes, understood.  This is another fine example of how changing a metric into a target means it is irrelevant as a metric anymore. Do on-time percentages mean much about airline efficiency? Not really–it just says who will bend the numbers to their best advantage.  GG imagines that Japanese visitors, accustomed to public transit that is exceptionally precise, must go nuts with American air travel…

So in the meantime we get to treat airline schedules as more like suggestions than actual timetables.