Stories in the bluffs

To understand the coast, at least in this part of the world, is to understand the soft, easily eroded bluffs that back much of the shoreline. I had the chance to stop by Port williams in Sequim Bay the day before Christmas Eve and, as is often the case while wandering beaches around here, i found myself awestruck by the bluffs. Two things in particular struck me about this site...first, the incredibly complex stratigraphy that given the interpretation of a better observer would have told stories that, I suspect, would go back at least a few million years. Second, this was one of the few places that I've actually seen "erosion notches" recorded in the base of the bluff...these notches are produced by high water and wave action eating away at the base of the bluff and are one of the hypothesized mechanisms of bluff failure...but I haven't really seen them anywhere else. So here are a few pictures from the walk:

A view looking along the bluff back (south) towards the Port Williams boat ramp

Look at that stratigraphy! McHenry for scale.

Notches cut into the base of the bluff...likely a product of the persistent high water of winter combined with wave action generated by the east wind we've been seeing a a bit of lately.

Okay, someone help me with this one. In places where there were pockets of well-sorted sand in the bluffs there were these things...clearly organic, parchment consistency...what are they?

Here they are in situ

a view seaward towards Protection Island from the site.

The latest sand deluge hits the beach

While the sand that hit the beach of the Elwha delta this summer was exciting, things really slowed down during the fall, and by October most of it had transported away (for more on this check out our poster from AGU 2012). The autumn beach, at least at my monitoring sites, was almost as cobbly as it had been at the beginning of the year. But perhaps due to the higher flows over the past few weeks (noting, though, that there still hasn't been a flow over 10,000 cfs this winter) and perhaps due in some way to the release of sand and gravel from the lowering of the Glines Canyon dam, the spigot has turned back on. Starting in mid-November a new pulse of sand arrived at the river mouth, this one easily larger, in both area and volumetric extent, than the one associated with Aldwell that flowed to the mouth of the river between April and July of this year. More to come on this, but here are a few panoramic views of the shoreline taken on the east side of the river.

This first shot was taken yesterday, 10 December 2012 at 4:40pm, looking shoreward from a point on my Line 164, about 300 meters east of the river mouth. This is a site I monitor routinely. The photo was taken from just above Mean Lower Low Water.

There was very little sand retained at this site just two weeks ago.

This next shot was taken from atop the berm on the east shore of the river, just upstream from the mouth, at about 4:30 pm.

Its not stunningly obvious given the perspective, but if you look close in the far field of this pano, to the right, you can see the two long shore-perpindicular bars that have built out from the river mouth. Both extend ~100+ meters or more at this point. Both weren't there a month ago, at least anywhere near that length or extent.

And finally, here is a view of the bar built on the west side of the mouth...couldn't pano this one, but this shot was taken at sunset on 10 December, at a water level of about -0.25 m MLLW. I walked out about 100m on to this brand new sand bar and shot this view back towards Place Road

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The Vexing problem of "tsunami debris"

The debris associated with the March 2011 Tohoku tsunami in Japan continues to turn our attention to the dynamics of the great ocean to our west. It must be the first time in history that the world's attention has been riveted by reports of single debris items (like last month's report of Hawaii's first confirmed item from the tsunami) washing up around an ocean basin. Its striking to watch this issue unfold and in particular how the uncertain science and modelling of wind- and current-driven transport across the ocean interacts with the concerns of communities. Above all it seems that communities, already struggling to wrap their arms around a host of crises, are wrestling with how much attention to pay this issue. Some sense of certainty would be nice...that is clear.

But for all of the oceanographic advances of the last few decades, the dynamics of the ocean still hold some mystery. As a result, most of the planning at the community and state level that I've been exposed to has adopted a very reasonable adaptive response capacity...the response will depend on what happens and given the huge number of scenarios that one can imagine its hard to outline one specific response plan. This approach may start to look like the wrong one IF we suddenly get a massive influx of debris that strains our capacity to mobilize resources quickly and effectively...but in the face of uncertainty it is difficult to justify doing otherwise.

At this point, a year and a half after an estimated 1.5 million tons of debris floated away from the coast of Japan, the uncertainty remains as large as ever. Debris will make landfall - that is a certainty if only because it already has. But the real questions are, "How Much?", "Where?" and "Will it cause damage, especially immediate damage?". This last question is not at all clear - the ecological effects of debris accumulation on beaches are not well researched or established. This leads to the fourth question, "Will the debris be of a kind (i.e. toxic or large) or volume that will overwhelm the capacity of existing systems to deal with it?".

So where is it all? What prompted me to sit down and write this blog was Dr. Curtis Ebbesmeyer's recent statements in the Peninsula Daily News. Dr. Ebbesmeyer is a noted debris-tracker who tracks and analyzes interesting flotsam from around the world, and he correctly surmised the approximate timing of landfall of the first items from the Japanese tsunami to make landfall in Washington State. Last week Dr. Ebbesmeyer was quoted in the Peninsula Daily News as saying, "the first big field of tsunami debris is about 400 miles off the Washington coast and probably will land on beaches next month". Dr. Ebbesmeyer suggested that this statement was based on reports from off-shore fishermen combined with results from an OSCURS ocean model. The Pensinsula Daily News then added that "Ebbesmeyer speculated that the main debris field, which is 2,000 miles long and 500 miles wide, could include items as large as buses, cars and parts of houses."

I think that what struck me about this is what an ominous picture it painted - a field of debris 2000 miles long by 500 miles wide is only 400 miles off-shore and headed for our coast. The implication, at least to me, was that we should expect all of this to come ashore shortly. The image conjured is of an overwhelming volume of debris pasted to the beach up and down the coast. However, other oceanographic modelling efforts suggest that we may need to paint a more nuanced picture to help us prepare. More and more I've been turning to the SCUD model results produced by the International Pacific Research Center (IPRC) at the University of Hawaii, and particularly some of their more recent analyses that integrate what was learned from some of the early landfalls of wind-blown debris. The video at the top of this post, for example, is a model hindcast of debris dispersion for debris items with various exposure to the wind (the sizing is odd - just click on the part you see and a full screen version will pop up).

I could stare at this animation for a long time, but I found that looking at model results for the various levels of windage in isolation was interesting and instructive. For example, the animation below shows only the modeled trajectories of particles with lots of wind exposure, and is consistent with the first arrival of the lightest items (floats, etc.) that were found in November of 2011 on Washington's coast. This animation also suggests, however, that most of this high-windage material had already moved away from the Washington coast by last summer:

Looking at items with slightly less windage we find a similar pattern, but see that we could have expected that most of this material might have come ashore in the late spring or early summer of 2012...exactly when a small bump in the quantity of debris on Washington's beaches was anecdotally reported by a variety of observers.

The no-windage category suggests that items that are not directly exposed to wind are moving much more slowly across the Pacific and are likely still well away from the coast:

But it is the mid-range windage items that may be the next big thing on our coast, and it is this debris that I assume Dr. Ebbemeyer was referring to. The model results for the 2% windage category (what exactly this means isn't entirely clear to me - but I will assume that it is items that are somewhat less buoyant than a plastic float, and somewhat more buoyant than something that is floating at or below the water's surface) suggest that some portion of this material is still making its way westward, even as most of it has already entrained in the broad southward moving California Current and is heading southward on its way to eventual entrainment in the North Pacific Sub-tropical Convergence Zone:

It seems quite plausible to expect, based on these results, that some of this debris may come ashore...but again we are really interested in how much, and there is no way to really predict that with much certainty based on any of the data sources that I am familiar with. For starters, its not at all clear what fraction of the total debris out there falls within this windage category (and therefore might be lingering just off-shore). Its also not clear exactly how windage affects how efficiently debris can be moved on to the beach from locations just offshore - it is thought, for example, that local coastal winds may play a big role in driving material on shore. If debris windage is reduced, therefore, it may not be blown on to the beach as easily. Couple all of this uncertainty with inherent model uncertainty and its easy to throw your hands up and walk away from the whole thing. However, if we make the assumption that the model tells us SOMETHING, than what is suggested by these model results is a small fraction of the total debris in this category should be expected to near the Pacific Northwest coast, and that some fraction of it could make landfall on Washington beaches associated with our typical winter "downwelling" winds.

But what these model results do not seem to support is that the entire field will come ashore, much less in Washington. Will we see more "tsunami" debris items...almost certainly. Will we see individual large items (i.e. cars or buses)? I have no idea, but it seems like it is still within the realm of possibility. Will we see huge quantities of debris? Well, that depends in large part on your definition of "huge", but these IPRC models, as well an analysis that I published a few months back, both suggest that the lions share of this debris will still end up in the Sub-tropical convergence zone and not on Washington's shores.

So now its time, as winter ramps up and the southwest winds blow, to test all of these model results against observations. Since I am spending far too much time inside these days, please, PLEASE, let me know what you are seeing on the beach...

Visualizing coastal disasters

Nobody really likes to think about coastal disasters...but some of us spend an inordinate time doing just that. We try to calculate risks, develop effective response plans and spread the word to our communities. Its the spreading the word part that can be most difficult. I think there are two reasons for this. First no one really likes to think about disaster - we already covered this - but, unfortunately, it is a necessity. Next, it can be very difficult to imagine the scale of disaster that coastal hazards can generate. Even in the face of a media onslaught related, for example, to Sandy, it can be hard to visualize exactly what is going on, and exactly what the victims are experiencing.

That is exactly why these visualizations put together by ABC News in Australia are valuable - they show in stark terms the power of these extreme coastal events, and the changes they can bring in a matter of hours. These are amongst the simplest tools for understanding change on the coast...and the most powerful. For the first two below they use a very nice scroll over tool that allows you to rapidly go back and forth between the before and after photo...very cool.

Check this one out on Superstorm Sandy

and this one about the March 2011 Tohoku tsunami

and this one, utilizing street view photos from Japan

The Night Time Shoreline

Last night I coordinated an optional field trip for my Peninsula College Introduction to Oceanography class. We met down at the boat ramp on Freshwater Bay, and "tide-pooled" our way along the western edge of the bay. The experience reminded me, again, that I should do this far more often. The night time low tides of winter are so much better than the day-time low tides of summer - organisms are out in the open, doing their thing, without having to worry about dessication. In particular I was startled by how many fish and soft-bodied invertebrates we saw. Hopefully some photos and student accounts will follow here...

We didn't focus so much on ID last night as simply trying to grasp distribution and diversity, but a good simple reference for the Salish Sea is the Beachwatchers program online guide book. My students asked for a list of species that we observed though, and while this list isn't complete and is based off of my own sometimes shaky ID skills (and is therefore not necessarily accurate in some cases - let me know if you see errors) it includes:

Fish "Tidepool" sculpins (Oligocottus sp.) at least a few Gunnel species (Pholis sp.) at least one other gunnel (Apodicthys sp.) Northern Clingfish (Gobiesox maeandricus)

Echinoderms Brooding Star (Leptasterias hexactis) Sunflower Star (Pycnopodia helianthoides) Rainbow Star (Orthasterias koehieri) Ochre Star (Pisaster ochraceus) Green Urchin (Stronglyocentrotus droebachiensis; this is a probable ID as it was a juvenile)

Crustaceans Kelp Crab (Pugettia producta) Red Rock Crab (Cancer productus; including females with eggs) Pygmy Rock Crab (Cancer oregonensis) Acorn barnacle (Balanus glandula) Thatched barnacle (Semibalanus cariosus) Rockweed Isopod (Idotea wosnesenskii) Helmet Crab (Telmessus cheiragonus) Hermit crabs (Pagarus sp.) Porcelain crab (Petrolisthes eriomerus) Shore crab (Hemigraspus sp.) A decorator crab species (perhaps Scyra sp.?) Broken back shrimp (Heptacarpus sp.) Other shrimp species (unknown)

Molluscs Black Leather Chiton (Katharina tunicata) Mossy chiton (Mopalia sp.) Mask Limpet (Tectura scutum) Clown Nudibranch (Triopha catlinea) Keyhole limpet (Diadora aspera; the number of keyhole limpets at this site was astounding to me) Mussels (Mytulis sp.) At least two whelks, probably Dogwinkle (Nucella sp.) and perhaps the Dire whelk (Lirabucciumum dirum)

Annelids Calcareous tube worms (Family Serpulidae) Sphaghetti worms (big ones! Order Terebellidae)

Tsunami Strike! Port Angeles (not) inundated

Compared to the "perfect" storm brewing on the east coast, the 7.7 quake that hit off of the coast of Haida Gwaii this weekend has received only limited attention. The West Coast and Alaska Tsunami Warning Center issued a tsunami warning for the northern part of B.C. and some of Alaska 30 minutes after the 8:04PM earthquake. By 1009PM, the alert had been extended as a "warning" for parts of Hawaii, and then at 1044PM, the alert had been extended at an "advisory level" for parts of the California coast (see this page for a description of the 4-tier tsunami alert system). The coast of Washington in general (including the Pacific Ocean and Strait of Juan de Fuca coasts of the Olympic Peninsula) were only included in the center's alerts at a "for information only" status.

But we did get "hit"...check out these water level data from the NOAA tidal gauge in Port Angeles Harbor:

A wave train of successive ~6 inch waves every 15 minutes for close to 8 hours, starting in earnest around 11pm on Saturday. Clearly, this tsunami posed no risk to communities on the Olympic Peninsula, but such an event always gives one pause...are we ready for a worse-case scenario?

There is a clear difference between the two "types" of tsunami we can expect on the Olympic Peninsula. A "local" tsunami would be very obvious, because it would be preceded by an earthquake that would, most likely, be at least strong enough to knock us off of our feet. Our tsunami warning system for such an event is built-in...if you are knocked off your feet then, if you are able, get to high ground as soon as possible after you can stand up again. For low-lying communities, or parts of communities, the planning that needs to happen is around escape routes, knowing who and where the young and infirm are, and mobilizing resources to get everyone to safety. Distant tsunamis, which are generated far enough away that we can't feel the earthquake associated with their formation, can still be powerful enough to cause damage. For the purposes of planning for inundation, no distinction is drawn between local and distant tsunamis. we have a set of warning systems in place that are worth looking into. Many centralized communities (i.e. Port Angeles, Lower Elwha, Neah Bay, La Push)have tsunami horns in place which are plenty loud to wake everyone up in the event of a tsunami warning. For homeowners who live away from those central areas, there are a series of alternate warning sources that would be put into service in the event of a tsunami warning covering our coast:

1) The Emergency Notification System. Homes can be directly called over their landlines and notified of emergencies of any kind. This system works only with landlines.

2) As of approximately spring 2013, Clallam County will add a new system that individuals can enroll in, which will route an emergency call to any phone (including cell phones/work phones, etc.) entered into the system.

3) Clallam County uses the alert system at Nixle.com to notify subscribers to any community-relevant alerts. A text is sent to your mobile phone...enrolling is free and easy (it took me about one minute).

4) And finally, the old stand-by...Clallam County Sheriff personnel, fire departments, or even the Coast Guard can all be used to directly canvas communities at risk. So, in the event of a tsunami warning, you could get a knock on your door from the sherriff...

Fun with HOBOs

We use HOBOs extensively for our work in the Elwha coastal zone, and I have become a huge fan of these relatively inexpensive but robust little devices. They are inexpensive enough that when I was starting to plan for this quarter's Introduction to Oceanography class I thought that maybe, just maybe, I could figure out a way to get students using them to collect oceanographic data.

My relationship with the Feiro Marine Life Center (I am on their board) paid dividends immediately. I mentioned my desire to build oceanographic "moorings" with students in my class to the FMLC director, Deb Moriarity, and she suggested that we might be able to use a bit of funds that the FMLC and the North Olympic Peninsula Skills Center Natural Resources program (via Dan Lieberman and Tara Morrow) were granted to enhance educational opportunities in the marine sciences for local students. I had a number of local students in my course and they also wanted to create connections with colleges. Perfect! To really do it right though, I needed a few more HOBOs, and I was able to get them simply by making a request of Onset, the company that manufacturers HOBOs. They were fantastic, and quickly donated four additional sensors in support of this education project.

a student engineered mount...for temperature and light measurements on the bottom...

What do HOBOs add? With my class we've taken temperature and salinity measurements off of the P.A. Pier. That was a great exercise, especially because many of my students had never before used any sort of data collection device. We were even able to use a Van Dorn bottle to collect samples from "depth". But single samples are lacking in context - to really start to look at patterns in the ocean we need to collect data in time and space. Usually the instruments to do this are prohibitively expensive or difficult to use, but HOBOs are relatively cheap and very easy to use. So I developed an activity in which my students would build three "oceanographic moorings" with multiple HOBOs on each mooring, deploy them off of the pier, recover them and analyze the temperature and light intensity data that they log every 30 minutes.

a mid-depth sensor. The engineering challenge was to mount the HOBO such that its light sensor is always pointed up towards the sky.

The HOBOs arrived in the mail Thursday morning, and by Thursday afternoon the students from my class had built simple moorings and had them in the water. The feedback was great and students seemed to love the exercise of trying to work out how to best mount and deploy the HOBOs to maximize data quality. This was an element that I had hoped for...if my interest was only in time-series data for my students to look at I could get it off of the NANOOS or NOAA NDBC websites. But the process of building and deploying the moorings was instructive in and of itself. Students had to think about tides and currents and how they might influence their moorings. They had to think about the various sources of energy in shallow water and build a durable enough system to withstand at least a week in the water.

A gentle deployment off of the pier

So they are in the water now...check them out:

There will be more to come as we recover and analyze our data. And once more, I can't thank the FMLC, the North Olympic Peninsula Skills Center Natural Resources program and Onset enough for their contributions.

in the water...if you see them please don't take them home...

Possibly the coolest beach clean-up video you will ever see

Beach clean-ups are not necessarily known for being a really exciting activity - we do them because we have to, because the state of the beach demands it at times. This video, though, begs to differ. Filmed and edited by Dave Forcucci this video documents a Surfrider Foundation (Olympic Peninsula Chapter) clean-up of a remote Olympic Peninsula beach on Makah land. Hiking stuff out of this beach would be a pain, so the US Coast Guard go involved...check it out:

Sea Level Rise on the West Coast

Sea level rise on the west coast is, deservedly, a topic that is getting a lot of attention these days, especially from those responsible for big coastal cities like Seattle and Vancouver BC. Also not surprisingly there are researchers focused on developing projections of sea level rise on a global scale and regional scale, who publish papers on their results. Then, every few years, some big multi-researcher effort will come along that takes all of the research and all of the papers and attempts to come up with a "we-all-agree-on-this" estimate that can be taken as representing the best available collective science. The Intergovernmental Panel on Climate Change is one of those massive global-scale consolidators of sea-level projections derived from researchers working all over the world. The Fourth Assessment Report, published in 2007, included projections of sea level rise (on the order of UP TO 60 cm by 2100) that, based on research published in the late 2000's, seemed too low. In fact, I draw exactly that conclusion in an assessment currently in development for the Olympic Coast National Marine Sanctuary.

Now, additional evidence to support that conclusion comes with the publication of the National Academy of Sciences report on sea level rise for the coasts of California, Oregon and Washington. In it, the cast of researchers involved (and the list is long), agree that sea level rise by 2100 may be more extreme than previously thought (on the order of UP TO 1.4 m by 2100). Here is Dr. Gary Griggs (who just happens to be my academic adviser from UC Santa Cruz) summarizing the conclusions:

These new projections are invaluable, because they incorporate the research from the end of the 2000's that suggests that the IPCC projections are too low. The one thing that I think is potentially of concern for those of us working in the Pacific Northwest, though, is the focus on deriving relative sea level estimates (they call them "regional" sea level rise projections in the report). Relative sea level takes the change in sea level due to ocean temperature changes, expansion of sea water, and added ocean water volume due to ice melt, and incorporates "vertical land movement" to come up with an estimate of sea level change relative to the elevation of the land. This is important, since "relative" sea level is what matters for communities planning for a changing sea level. For example, even if "eustatic" sea level (the "true" change in the level of the sea away from land) rises 1.0 m in 100 years, the relative sea level will be much greater in a place like New Orleans, where the land is subsiding, than in a place like Kodiak, Alaska, where the land is rising.

The projections presented by Gary in the summary, which are also featured in the executive summary and elsewhere in the report, are relative and attempt to take vertical land movement into account. This is conceptually okay, but there is an assumption in Dr. Griggs' summary that the entire coast north of Cape Mendicino is uplifting at about the same rate. The evidence suggests, though, that there is quite a bit of variability in rates of vertical land movement around the Pacific Northwest (see also this reference on the topic). In other words, the relative sea level projections offered by the NAS should be used cautiously in the Pacific Northwest since, for a particular community, they may really underestimate the likely sea level over the next 100 years. Instead, we need to take their updated projections of eustatic sea level rise and combine them with community-scale estimates of vertical land movement to really come up with useful projections for cities and communities to work with.

Regardless of that small oversight on the part of the NAS, Gary's final conclusion is dead-on: "Coastal communities need to begin to understand these processes and what sea-level rise indicates for them, and plan accordingly"

More than you ever wanted to know about the Elwha...in four short videos

A few online videos have been published recently that I wanted to push, all focused in one way or the other on Elwha research. the first two are from the Elwha Science Symposium. The opening night of the symposium was held at Peninsula College and was free and open to the public. It featured Lynda Mapes, Jeff Duda and John Gussman...

Elwha Science Symposium - Monday Night Public Event from Peninsula College on Vimeo.

Then on Wednesday a panel of selected researchers, each representing a discipline, presented:

Elwha Science Symposium - Wednesday Science Forum from Peninsula College on Vimeo.

and this one is a recording of me speaking on the coastal response to the dam removal at the Science Cafe event in Tacoma in June. These events are awesome...it was a true delight to give a full-on nerd talk with a beer in my hand.

And finally, a nice little synopsis video assembled by USGS of the Elwha sub-tidal monitoring program:

The 2012 Elwha Symposium

I served on the planning committee for this year's Elwha Science Symposium, which took place last week at both Peninsula College and NatureBridge. This year's event was great, with a few highlights for me. Notably, I was very involved in pulling off the public forum on Monday at Peninsula College. One of the things we tried to do was to ask researchers presenting science posters at the science sessions later in the week to bring their posters for viewing by the public. I wasn't quite sure how this would work out, but it seemed like a huge hit, with people stacked up in the hall checking out the latest work from a variety of investigators in a variety of disciplines. My own poster on the response of the shoreline to the removal of Aldwell dam:

is available for download in full resolution here.

With support from the Bureau of Reclamation and Peninsula College we were also able to webcast both Monday's public forum and a special science session on Wednesday morning. Working with Eric Waterkotte at Peninsula College on this was awesome, and we've ended up with a nice, widely available record of the events as a result. Both sessions will soon be available on-line, with access instructions for both sessions here.

Finding the sand from the Elwha River

I've posted recently about the sand that is accreting to the beach near the river mouth of the Elwha River. I and others are tracking this carefully to determine if and when the removal of two dams on the river acts to halt or reverses chronic erosion along the delta. Last week I also went out for the first in a series of dive sessions, with other divers from the USGS, the Lower Elwha Klallam Tribe and the EPA, to monitor a series of sub-tidal sites near the Elwha River mouth (the red dots in the photo below):

At each site we are collecting a suite of data to describe the invertebrate and kelp community, as well as the substrate. We started this project in 2008, and more information on the project and the biological community off-shore of the Elwha can be found here.

The new sand on the beach made me think that we might see some new sand at some of our sites, especially the shallow sites to the east of the river mouth. But I was struck by how similar everything looked (as reported by the Peninsula Daily News), from a grain-size standpoint, to our surveys from the previous year. So we went hunting for it...

We decided to enter the water at our monitoring site "D1" and swim a transect to the river mouth along a line that is surveyed at least once a year by the USGS for bathymetry:

Preliminary results from the most recent USGS bathymetry survey, in May 2012, suggest that there had been new sediment added to this transect between September 2011 and May 2012:

This is a series of profiles collected along the transect since 2005 (courtesy of Andrew Stevens, USGS), showing the transition of this particular slice of the earth from a beach to a river mouth (between about 2005 and 2008), and the subsequent accumulation of sediment in the shallow coastal zone (since 2008). Between September 2011 and May 2012 there was more sediment added...and I wanted to know what its composition was...sand? sand and gravel? mud?

The video that we collected gives it away. I shot video at various depths as we moved up the slope towards the river mouth. Each of these video segments is prefaced by showing the profile again, with a black arrow that corresponds to our position on the profile. Enjoy!

Recent Article in the PDN on the Elwha

I love my local paper. I am a loyal subscriber, and have no plans on ever changing that. In an age defined in part, we are told, by dying print media, I want to do everything I can to keep the Peninsula Daily News chugging along.

That being said, I have been known to criticize the PDN when it comes to reporting on the sorts of coastal scientific issues that I am most familiar with (see my blog post titled "Where Do They Get This Stuff From?" from last December).

But I'm overall pretty pleased with Arwyn Rice's article from yesterday, "Researchers Excited By Early Signs of Elwha Changes" and thought that she did a good job trying to capture what I was trying to say, representing the uncertainty in our science, and forming it into a decent summary.

That being said, lets move on to the errata. First, when Arwyn writes that "Once a sandy beach existed just east of the Elwha River mouth" the implication is that I said that. I didn't. In fact, there is virtually no evidence that this was the case. Really the only data that I've seen suggesting what the grain size on the beach was like prior to the dams comes from an 1908 Coast Survey chart, which marks the shoreline near the mouth as "Sand and Pebbles"...suggesting the possibility that it was sort of like what we see now.

Next, Rice quoted me as saying "In the past 15 to 20 years, erosion has taken 12 feet per year". If I did say that, I am sorry. What I should have said is "erosion has taken UP TO 12 feet per year on average". Erosion in places and over some time periods has exceeded that rate, and in others it is less. Erosion is like that.

Also, as I've written in the past, i am not yet willing to say that the removal of the Elwha dams will "rebuild Ediz Hook". To be fair this statement wasn't attributed to me in Arwyn's article, but it may be interpreted as such by association. I'm not ever sure that Ediz Hook needs "rebuilding" so much as a different perspective on how we manage it. But that is a complicated story, one that needs some study, and is definitely for a different time.

Not quite sure where this came from, "The amount of sediment to be deposited from the dam removal is the equivalent of a 100-year or 500-year event, he said." I think that one is mis-attributed since we didn't really talk about sediment quantities observed at the mouth, and I wouldn't have had much to say there anyway, since we don't yet have good data on that topic.

And finally, and really digging into the weeds, I can see why Arwyn wrote, "Once Lake Mills is removed, the river's sediment load will increase dramatically, he said." since we talked about how a larger fraction of the stored sediment in the Elwha system is still stuck in Lake Mills. But the term "load" is some circle suggests that the amount of sediment that the river is carrying at one point in time, versus the long-term delivery to where I care about it - the mouth and coastal zone. The instantaneous load may or may not increase when Glines comes out(it will probably depend more on river flow than anything), but certainly the amount of sediment available for transport down the river will increase.

Boat-based LiDAR to measure bluff erosion

The shoreline of the Strait of Juan de Fuca, like much of Puget Sound and even some of the outer coast of Washington, is a strip of tall and very actively eroding bluffs. These bluffs, built primarily of loose sediment deposited by retreating glaciers >15,000 years ago, are the subject of considerable interest in the management of marine resources in our area. Despite being fairly easily eroded, their edges seem to be preferred places to build homes. Great views, indeed, but over even relatively shore time periods - 10 or 20 years - these bluffs can move shoreward due to erosion many 10's of feet. In most cases regionally and around the country, their have been two inevitable outcomes: 1) Either homes are lost to the sea, or 2) the bluff is "armored" in some way to reduce or stop erosion. This engineering solution, while attractive at first glance, carries a hidden cost - the sediment eroded from the bluffs deposits on the beach at the base of the bluff, where it can contribute (via processes that we are only just starting to understand) to building habitat. In some cases, the connection between bluff erosion and habitat-building processes seems stunningly clear; Dungeness Spit, widely considered a regional gem in terms of coastal habitat, is probably maintained almost purely by the erosion of soft bluffs to the west.

The WA DOE research vessel R/V George Davison (in the far field, right) scans the bluffs immediately east of the Elwha River delta

Despite the apparent importance of these bluffs to shallow marine habitats, our understanding of how they erode, and how much they erode, is surprisingly naive. Most of the work that has been done to quantify rates of erosion around Puget Sound and in the Strait of Juan de Fuca was/is done by drawing lines on aerial photos taken at various times over the last century or so. This was state-of-the-are even 20 years ago, but there are a lot of uncertainties when making measurements off of photos - how good is the photo? Does vegetation block the view of the bluff edge? Does the line actually represent the bluff face, or is the bluff face overhung? Also, it is very difficult to quantify the volume of sediment contributed to the beach from aerial photos.

A ground control marker on the bluff west of Port Angeles

As a result, new techniques are warranted. Over the last 10 years or so there has been an jump forward in remote sensing technologies, including Light Detection and Ranging (LiDAR), which uses a laser fired from a scanner to very rapidly estimate the distance to a surface some distance away. Associated with a high-precision GPS unit, and a device called an inertial motion unit, it is now possible to very quickly collect hundreds of thousands of discrete measurements of a surface from a moving vehicle. This has been done from planes for a good two decades or more, but planes aren't the best platform to measure bluffs from, since the bluff face is oriented up and down relative to the plane. Last week, for the first time, bluffs in the Strait of Juan de Fuca were scanned from a LiDAR unit mounted on a boat. Using a boat, large distances of bluff can be scanned fairly quickly (miles of bluff per day).

Diana McCandless, WA DOE, surveys a ground control point on the beach east of the Elwha River delta

These bluff erosion measurements are led by the WA DOE Coastal Monitoring and Analysis Program, with support from WA Sea Grant and WA DNR. My role in this project was to help with local logistics and help set-up ground control points - large targets visible on the boat that can be used to assess how well the LiDAR scanner is measuring the surface. Our goal is to measure bluff erosion as a volume (i.e. so many cubic feet of sediment were eroded from the bluff over x number of years), and so the ground control points allow us to add error bars to that estimate. The first survey was a huge success - a least logistically. We had phenomenal support from private and public land-owners all over the county. And this bluff measurement project isn't even the whole story...it is just a part of a larger project coordinated by the Coastal Watershed Institute, with involvement by Clallam County and Earth Economics, as well as a whole suite of supporters.

A reminder - we face other coastal hazards...

This photo was taken by Dr. Sarah Sterling a few weeks back in a salt marsh west of Port Angeles. The sand layers at inch 26 and inch 28.5 on the ruler are unequivocally related to tsunamis, which push marine sands up into the salt marsh. Nearly identical sand layers are found in Discovery Bay, east of Port Angeles. The layers shown here are probably from tsunamis that happened hundreds of years ago. The scale of these layers suggest a pretty substantial tsunami that may be associated with a rupture along the Cascadia subduction zone, just 50 miles off of our coast. Seeing these layers was a reminder to me that someday - perhaps sooner, or perhaps later - we (the Olympic Peninsula) are going to experience another of these big earthquakes and/or tsunami. And the evidence from this photo and from Discovery Bay suggests that tsunamis here can be of a scale to powerfully affect the entire shoreline of the Strait of Juan de Fuca. I bring this up as a reminder - the news is filled these days with hand-wringing and nail-biting regarding the landfall of debris from the March 2011 Tohoku tsunami on our shores. Tsunami debris is a hazard, no doubt. Pile enough plastic on the beach and bad things happen. Enough of it in the water probably poses a toxicity risk, not to mention endangering wildlife and even creating navigation hazards. But I find that I cannot wholeheartedly agree with Chris Pallister, who runs an organization dedicated towards cleaning debris from the shores of Prince William Sound, who was quoted in an article today saying, "I think this is far worse than any oil spill that we've ever faced on the West Coast or any other environmental disaster we've faced on the West Coast". That statement ignores the environmental problems associated with the huge volumes of marine debris that enter the ocean EACH YEAR (far more plastic debris is probably released into the ocean as non-point pollution than from the Tohoku tsunami)and also downplays the devastation associated with large oil spills. The statement also seems to downplay the risk that we face from seismic events and tsunami, and I can't even give Chris the benefit of the doubt and assume that he is talking about events only in recent memory. Its only been 48 short years since an earthquake and tsunami wrecked SE Alaska, killing 119 people in the process. The calls for greater preparedness for the tsunami debris are warranted. We will have to put our collective shoulder to the wheel to get beaches cleaned up, and some intervention by state and federal government may be necessary to deal with big items, toxic material or invasive species. But those loud calls, in my humble opinion, should be accompanied by, and I would argue overshadowed by, louder calls for better preparation for a local seismic event and tsunami...

The Changing Elwha shoreline

While the removal of the Elwha dams is not yet complete, we are already getting a taste of the potential restoration benefit and scale of this project. Starting a few months ago we started to see sand on the beach in places where we never had before. Every few weeks I head down to the Elwha delta and measure a beach profile and collect grain size imagery at 3-4 set monitoring locations (the ones in red in the photo below): On 24 April 2012 I put together a little summary based on some observations of NEW sand, tentatively attributed to the dam removal, at one of three sites that I monitor every few weeks. This is from Line 164, just to the east of the river mouth, and you are looking at a profile collected on three different dates, plus some grain size photos and oblique photos of the beach: This sand accretion was relatively high up on the profile, around 0.5m (1.5 feet or so) above MLLW. While very cool (this was, after all, some of the first sand that I could attribute to the dam removal that I observed on the beach), the amount of sand, and its extent along the beach, were both pretty minor. Now, though, the lower tides of May and June have given us a better view of sand accretion lower down on the profile - and it turns out that this is where a lot of the action is. Right around the river mouth there is a substantial body of sand that I first observed at the beginning of May: (Sorry about the wind and bad audio in this vid). At the time it wasn't clear if this sand would persist, or if it was a temporary blip in a longer-term reconfiguration of the Elwha delta in response to the addition of new sediment from the dam removal. It now appears, though, that the various sand bodies are growing and seem to be set to stay. For example, this set of profiles from today, and 5 July 2011 (about a year ago), suggests there has been substantial profile accretion below about 0 MLLW (where the black line, representing the surface today, is well above the gray line, representing the surface in July 2011): and the grain size shift associated with that accretion is readily apparent in these "before and after" photos taken at an elevation of -0.15 m MLLW at line 164 on 5 July 2011 and today: I was also surprised to find that the fine sand depositing down low on the beach extends far to the east. At Line 204 the profile was covered with fine sand below a depth of about -0.25 m MLLW, as you can see in this series of photos taken at 0.25 m elevation increments starting at -1.00 m MLLW: While I don't have any grain size photos from earlier dates to compare to for this relatively low part of the profile (today's low tide was exceptionally low - I don't often get the opportunity to sample below MLLW), my own observations after 5 years of work out there suggests that this sand is NEW. While the upper beach itself looks about like it always has around most of the delta, at line 164 that small sand body that I originally reported on at the end of April (see above) seems to have grown and has now welded to the base of the foreshore. Here you can see a photo taken from low on the profile looking towards the shore, with a bar of sand that has attached to the upper part of the beach. Comparing profiles from today and two weeks ago (May 20), that profile growth is very clear...all sand. This observations is particularly interesting in light of one of my major motivations for doing this - this beach is seriously erosive, and I am interested in "if, how and when" the sediment associated with the dam removal may act to reverse the chronic erosion that causes all sorts of problems on the delta. This sand accreting to the foreshore is some of the first evidence that the upper part of the profile, which is the part that erodes so rapidly, might enjoy some sort of restoration benefit from the dam removal...very cool stuff. Thanks to colleagues at the US Geological Survey and the Lower Elwha Klallam Tribe for helping to collect and interpret some of the data you see here...

Time Lapse of the Elwha

Its been a while since my last post - as the field season ramps up time in the office has been squeezed. But as the days lengthen and we get more sun the conditions for photography improve, and the imagery coming in from our time-lapse cameras pointing at the Elwha delta are really nice. This on-going effort is designed to further our understanding of the dynamics of the Elwha River plume and to track gross changes to the morphology of the river mouth. This last series that came in from Fox Point is really nice - the plume is mesmerizing as it swings back and forth under the influence of tidal currents. The lower tides at the end of this series (early May) also show some of the morphologic changes we are seeing at the river mouth...

Olympic Coast Clean-up

A 4:45 am wake up is nothing to be trifled with, and I loathed it as the alarm popped off this morning. But even in my morning haze I had to admit that I was a bit excited. From 2003-2006, when I worked for the Surfrider Foundation, I worked every year to pull off the Olympic Coast clean-up, and this morning I woke up and headed out to the coast for this year's event, my first since those SF days. Along with a group from ONP and The Surfrider Foundation's South Sound Chapter I manned the registration booth handling Rialto Beach (including the cove north of hole-in-the-wall), First Beach, Second Beach and Third Beach. While I am as in to cleaning beaches as the next person I had a secondary goal - use the observations of the 100+ people volunteering their time to examine two questions: First, can we use the data collected during the clean-up to identify "collector" beaches - places that, because of the vagaries of wave hydrodynamics or nearhshore currents collect relatively more stuff than other beaches. There is great interest on the outer coast in this question because of its potential importance in planning for an oil spill. Next, given the volume of reports coming in that seem to suggest the arrival of significant quantities of tsunami-related debris on our coast, I was interested to observe the debris pulled off of these beaches - would we see more than we have in the past? Would we see a lot of debris with Japan? Note: Check out this article about some of the first CONFIRMED beach debris from the tsunami in Alaska. First questions first. In talking to volunteers as they returned it immediately became clear that, of the beaches considered, Second Beach seemed a good candidate to be a "collector". Multiple volunteers talked about coming upon significant collections of trash, and one party described spending two hours on a 200' section of beach. I wanted to take this further. Each volunteer collects data as they clean the beach, and I was able to quickly enter a few key bits: How many people in their party, how many hours they were on the beach, and their estimate of the weight of debris removed from the beach. Using this data I was able to estimate the total weight removed from a particular beach during the day, the total effort on the beach (in person-hours) and I then was able to measure the total length of the beach from Google Earth. This allowed me to calculate a metric that, while, rough, provides some estimate of the debris removed from the beach for a give effort and distance. I think of it as the beaches "debris production". And, using the magic of Excel for quick plotting, voila...

Shown here are mean production rates, by party, with the error bars showing the standard error of that mean. The pattern suggests that, indeed, Second Beach may have a higher debris production than Rialto (though its not a significant difference). Third Beach looks higher, but I had only one sample for that beach - one party that reported their information to me, so that number should be considered suspect since there was, not unsurprisingly, lots of variability between parties. And we didn't end up with any parties on First Beach today since it was cleaned yesterday, so I couldn't include it. But in the end I like the method - and we may actually be able to discern some meaningful patterns if we can do this analysis on clean-up data going back to 2003... On to question two - I had sort of a vague hypothesis going into today - that if the reports of buoys and other large floaty objects washing up on our coast were from the tsunami, that it might be reasonable to suspect that other relatively floaty things - particularly bottles, would be found as well in relatively large numbers. In other words, we might expect to see a disproportionate number of plastic bottles collected from the beach from Japan, as compared to other locations. At the end of the day we had a flat bed truck full of bags of bottles sorted for recycling - there was my sample - and I spent about an hour going through it.

Certainly we found objects that we tentatively sourced to japan based on visible script (particularly buoys and bottles). I didn't have the time for real quantification (though such a project would be very useful) and was forced into some broad estimation, but my guess is that about 25% of the bottles were definitely from asia, 25% appeared to be local (i.e. from the U.S. and probably either from land-based sources or nearshore boats) and about 50% had no discernible markings, making it impossible to determine their source. As an aside, a few were particularly interesting. We suspect that these two were from the Middle East and Russia, respectively:

But back to Japan...of the 25% of the bottles that I had some confidence were from asia I could positively identify some bottles from Malaysia, Singapore, Hong Kong and the Phillipines, usually based on a bit of English here and there, or in some cases, like this bottle from Hong Kong, from the country code on the URL on the label:

Other bottles we tentatively sourced to China and Japan based on the script (noting, however, that none of us had ever studied those languages). Here are a few examples of those:

Notably, though, of all of those bottles from Asia (an estimated 25% of the total) there didn't seem to be any type or script that was dominant. Additionally, there seemed to be no more bottles, or debris in general (based on my recollection), than in any other clean up year that I've been involved with. Other debris patterns also didn't point to a significant load (i.e. outside the normal baseline) from Japan. We were given a set of photos of buoys tentatively associated with the tsunami debris, which all volunteers were asked to look for and track separately. Of the buoy types that we were asked to identify (6 of them) we did find some, including two of the rabbit ear type:

and at least 1 of a big round polysterene type that you can see in the back right corner of the flatbed truck in the photo above. We also found two large containers that looked vaguely like types associated with Japan, but they were blue and of a different configuration than the ones in the photos we were provided:

This is all just observational evidence, and certainly not a proper test of the hypothesis above. But again, given some of the accounts that I've heard, part of me was expecting a fairly significant debris signal from Japan already, and I don't feel that we saw that at all. Not a surprise I suppose, models suggest the bulk of it will arrive later this year at the earliest...but some of the comments and observations I've heard of late have led me to believe that observers were seeing a lot of items on the beach already from the tsunami. We certainly can't say that we saw that today. As an aside, if anyone does read Japanese or Chinese, I can send the photos I took today of bottles - it would be interesting to confirm their source. Email me at immiller@u.washington.edu

Flying over the Elwha

Before graduate school, before moving to Santa Cruz, we lived here in Port Angeles and I worked for the Surfrider Foundation. In that capacity I developed a project whereby volunteers could go out and photograph the beach at set locations using defined protocols. The idea was to develop a consistent visual record of change. Sadly, I've recently discovered that the web-based portal that we developed to host the photos has been taken down, but the protocol is still in use (more on that in future posts).

Part of that program involved getting volunteer pilots to fly photographers over the shoreline, and I ended up doing that a few times between 2003-2006. And it turns out that its quite fun to do AND some of the pilots who volunteered their time are still into it. So a few days ago I got a call from Richard Watkins, who has flown me around numerous times to check out the Elwha from the air, take photos, and look at the various processes shaping the coastal zone. And, on Tuesday, we went up again, and it was beautiful.

The photos collected from the air and on the beach have turned out to be quite valuable to many in the research community. They've appeared in publications and reports, and have been used to guide our thinking regarding how the Elwha is evolving, to establish a baseline against which change can be measured, and even to understand the management of Ediz Hook (more on that in a future blog post).

Some images from that flight are here. It was a pretty calm day, but the river below the dams was pretty turbid, and there was a defined plume. At the middle of every ebb tide, the plume whips around to the west and diffuses a bit (you can see the plume migrating back and forth in one of our timelapse videos), and that was the state in which we found it (the low tide was about two hours after our flight). The features in the plume were amazing. We also flew up the valley to check out the two (former) reservoirs. I've included a photo of the lower reservoir here, which is now fully drawn-down with river flow throughout.

The Pile

I wish I had remembered to take a photo of my office this morning. After a good dose of field work this last week it had become a pile of wet outerwear, surveying equipment, our cobbled together rock-tracking RFID reader, rubber boots, and random cameras, ropes, and instruments waiting for download. A true mess, and one that had me dreaming of things like storage rooms and lab spaces. I am feeling quite a bit more balanced after wading through it, putting everything back in its place and getting all of the data downloaded and backed up.

Yesterday was an almost full day working with a Huxley student on a project that is an out-growth of my graduate research tracking rocks. Here is Chris digging in the beach - so much fun on a rainy day...





Its been a good couple of years since I last tracked rocks, and yesterday I was reminded that it is both really fun and really trying at the same time. As always though, there is a surprising bit to learn about how beaches work by watching things move around. Yesterday was pretty interesting because the wave energy, which normally approaches the Elwha from the west, didn't behave. In the morning, just before the water level dropped, a BIG east wind swell cropped up. Here is the timelapse of the tidal cycle. Note the big waves at the end - you are looking west towards the Pacific Ocean.










And finally, a new game I call find the tracer:

Views from the Aldwell delta

As the removal progresses the delta is spreading out along the reservoir. Stumps logged off in the early 1900's are exposed for the first time in 100 years, looking like they were just cut...a few views from a walk around the Aldwell delta from this morning:












































and a view of the dam...I've zoomed in on the original channel canyon, where the dam once stood - its totally gone, with the river looking pretty ready to re-occupy its original channel for the first time.