Thursday, August 10, 2017

Sites and sounds from this summer's return to the Elwha sea-floor

An embarrassment of tube worm riches, site E2, July 31 2017

Last week was our first week of diving for our annual (since 2008) sub-tidal site monitoring effort in the marine waters near the Elwha River Delta (i.e. here and here). Overall my take away is that the system "looks" very recovered relative to during the peak of dam removal in 2013 and 2014 (i.e. see the two comparative videos here). Here is a recent example, Site H2 in 2013, during dam removal. In particular in this video pay attention right at the outset to the turbidity visible in the water column, as well as the general lack of algae:

we returned to that site this summer, and here is the look see:

and now on to just a few highlights from this year:

Observed for the first time in our surveys, the orange peel nudibranch (Tochuina tetraquetra). This thing was big...probably 6-8 inches in length...

fan hydroids

We work out of the US Coast Guard Base on Ediz Hook, and this massive ball of herring was at the dock the entire week

The world's largest barnacle, Balanus nubilus, at work

Observed at Site C1, something we used to see a bit before dam removal...a Bull Kelp (Nereocystis leutkeana) growing attached to a tubeworm (in this case Spiochaetopterus sp.). Typically Bull Kelp will attach to bedrock, boulders or large cobble.

Saturday, July 22, 2017

The greening of the Elwha delta

I was out on the Elwha delta over the last two days, working with the staff from the US Geological Survey and Department of Ecology on the roughly annual topo/bathy survey of the Elwha delta. My role is to collect grain size photos and sediment samples. As we were cruising around the delta this year I was struck again by how the vegetation is really taking off on the new delta deposits laid down during dam removal. The photo above was shot this morning looking north (towards Vancouver Island) from roughly where the "A" is on the map below: and here is the view from the same location in May 2012: Such an incredible transformation. A huge thank you to Emily Portillo from the Washington Conservation Corps for assisting with the grain size sampling over the last two days!

Friday, June 16, 2017

The dynamic coast

I've been geeking out lately on Google's Earth Engine time lapse tool, which I first learned about a few years back, and which is a startling accomplishment in and of itself.  Basically Google has hoovered up and integrated every Landsat image ever collected to create a continuous time lapse of the earth's surface dating back to 1984.  While those imagery are fairly coarse resolution (around 30m in most cases), they easily pick up large-scale coastal changes and coastal sediment dynamics (like the above, from the Pysht estuary on the Strait of Juan de Fuca where you can actually see fluvial sediment being transported on-shore over decadal time-scales)...which has led to my geekery with the tool.  Here are a few highlights from coastal Washington (with credit to Hugh Shipman for pointing to many of these awesome locations).

Above, the Elwha, with a few highlights, including of course the massive flux of sediment and formation of new estuary/river mouth bar complexes associated with dam removal, and the formation and transport of a few cuspate foreland type features on the east side of the delta.

oh man, the Dungeness River delta and much going on.  Westward transport of sand bars off of the delta, extension and evolution of the Spit, on-shore migration of off-shore very cool.

Grays Harbor much going on here.

but maybe not so much as the Willapa Bay inlet, which also features Washington State's slow-moving erosion disaster at the neighborhood/town of North Cove:

Useless Bay on Whidbey Island is just an absolute conveyor belt of sand waves moving along the shallow sub-tidal:

and check out the Stillaguamish snaking into Port Susan:

Its not quite coastal (though it IS related) - watch glaciers on Mt Olympus shrink before your eyes:

And similarly, not quite coastal, but Oso:

Tuesday, June 6, 2017

Building ROVs on the West End

A team from Forks Middle School presenting their ROV to a group of judges
I am raising my kids on the Olympic Peninsula, and it takes a lot of work to feel like they have opportunities for enriching STEM activities that youth in more urban areas do.  And I'm saying that even though we live in Port Angeles, at 19,000 people the largest community on the Olympic Peninsula.  I can't even imagine what parents and students in some of the smaller and more rural communities on the west end of the Olympic Peninsula must experience.  To help in some small way to provide an opportunity is one of the reasons that I enthusiastically signed on to be a judge for the first ever MATE ROV Satellite competition, organized with help from the Olympic Coast National Marine Sanctuary, and held at the Forks, Washington pool on 20 May.

The Expeditioners from Lake Quinault School, presenting their poster.  This team won an award for, "Best Team Spirit" during the competition
This was my first ROV competition, and I must say that I was impressed.  The competition organization is phenomenal, with a rigorous system of rules and scoring.  Even more impressive was the effort put into the contest by the roughly 20 teams in attendance, representing schools from Lake Quinault, Taholah, Forks, La Push, Clallam Bay and Neah Bay.  Most of the teams represented were starting from the same point - in all cases that I saw starting from one of these kits - but from there teams diverged widely in terms of their solutions to the various challenges they needed to deal with.

The poster presentation and ROV for one of the teams from Clallam Bay High School, with some really nice engineering touches.  This team did a lot of trial and error testing, and came up with some innovations.

By way of example, check out this student from Lake Quinault School walk us through his team's ROV design:


So very cool.  I'm definitely in.

Monday, May 8, 2017

Moving pictures of all kinds...

We managed to pull off yet another year of the River and Ocean Film Festival (the 4th one!), which I organize each year along with the North Pacific Coast Marine Resources Committee.  As I told the audience this year I'm in to doing this because I think that film is such a great way to tell stories about the places we live, and allow people to see and experience views and perspectives about their landscape that they never would otherwise.  This year we had a great audience and great feedback, but if you were one of the many people that were NOT there you can see many of the films (along with those from previous years) here.

And since we are premiering films, I also wanted to point towards a set of videos that we, along with USGS and the Lower Elwha Klallam Tribe, just published on USGS's Youtube page.  They collect in one place all of the "transect" videos we've shot on the sea-floor around the Elwha delta...and since these videos are shot at a selection of "fixed" points you can sort of click through them to see how the sea-floor and coastal ecosystem changed through the dam removal.


Friday, March 24, 2017

Glass Beach

I'm going to take a page out of Hugh Shipman's book here and take a stab at profiling a section of shoreline I had the opportunity to explore last weekend.  If you wander west from Port Townsend along the Strait of Juan de Fuca you will find a few treasures.

First, just a stunning, active, classic eastern Strait of Juan de Fuca bluff backed shoreline.  This stretch is complete with perplexing and beautiful stratigraphy, plenty of signs of active erosion,  and also plenty of futile efforts to control that erosion:

Next, beach glass!  This is why we try to find a mythic glass beach that I had heard whispers of.  These sorts of places are scattered along the coast (including perhaps the most famous of them all in CA?), presumably related to old but poorly documented informal dump sites.  Beach-combing for glass is one of those things that everyone in our family seems to love, so it was a treat to try to make it to this well-known glass hunting beach:

As it turns out we didn't make it all the way to the best sites, but made it plenty far to scratch everyone's itch:

Friday, March 3, 2017

Anatomy of a Coastal Storm: March 10, 2016

Nuisance flooding in Freeland, Washington on Whidbey Island after the March 10 storm.  Unknown photographer, photo courtesy of Island County Department of Natural Resources.  
We are coming up on the one year anniversary of the 10 March, 2016 storm that really walloped many communities in northern Puget Sound (see this link as well) and on the Washington Coast.  It was an interesting storm for a variety of reasons and in particular it seemed to impact coastal areas in northern Puget Sound in ways that those communities were not accustomed to. Perhaps as a result I've heard people refer to the March 10th storm as a "100 year storm" from the standpoint of its coastal impacts.  As a result I wanted to use this blog to look in a bit more detail at some of the aspects of this event in in relationship to the coastal impacts associated with the event.

Overwash of sand, gravel and wood on to a road near Oak Harbor, Washington.  Photo courtesy of Lori Clark, Island County Department of Natural Resources
The photos above, and indeed many of the most significant impacts associated with this storm were focused in Island, Skagit and Whatcom Counties, but there is a distinct lack of tide gauge data up in those parts.  So I'm going to focus first on Port Townsend, where there is a tide gauge.  To be clear the storm was exciting there too.  The photo below shows a distinct debris line and nuisance flooding adjacent to the Jefferson Title Company building in Port Townsend on the morning of March 10:

photo courtesy of David Wilkinson
Here are the water level data collected between 5 March and 15 March, 2016 at the P.T. tide gauge, located just east of where this photo was taken:

When interpreting these data I am going to distinguish between three different water levels; first the "astronomical tidal water level", which I will also refer to as the predicted tide (shown in blue in these plots); next the non-tidal residual, which I will refer to as "storm surge", which is the difference between the predicted (or astronomical) tide and the measured water level (shown in purple in these plots); and finally the actual measured water level, or "still water level", which is the sum of the two (shown in green in these plots).

So in P.T. the total measured water level measured during this event WAS high - the peak measured on the morning of March 10 was 3.41 m relative to MLLW...but this is nowhere near a "100 year coastal flood water level" for P.T.  In fact since the current tide gauge was installed in 1972 that water level has been exceeded numerous times, with a maximum measured water level of 3.57 m relative to MLLW reached on 12/10/1993.  NOAA places the March 10, 2016 measured water level as having somewhere around a 1-in-5 year recurrence interval, or a roughly 20% chance of occurring in any given year.  Here is another way of looking at it:

These are histograms of hourly water level data dating back to 1972 in Port Townsend, with the metrics associated with March 10 in red.  At the top is the predicted or astronomical water level...and here the predicted tide on this day wasn't particularly high, but the NTR (the panel at the bottom) is pretty high, but again nowhere near the highest on record (that record was set on 1 Jan 1997 in Port Townsend when the non-tidal residual was roughly half a foot higher than the surge on March 10). So indeed, the "still water level", as measured at the tide gauge WAS indeed high, primarily because of some pretty good "storm surge", the peak of which more or less coincided with high tide...but nowhere near a 1-in-100 year event.

So what compelled us to look at March 10th as extreme?  Well, clearly wind, and wind-driven waves, played a major role in driving flooding during this event.  Here is another photo taken the morning of March 10, 2016, looking south from the south-facing shoreline of downtown Port Townsend:

Photo courtesy of David Wilkinson
There are no wind data available for that event from the P.T. tide gauge, so I turned instead to average wind data (these are averages over an 8 minute period) dating back to 2004 available from NOAA's Hein Bank buoy in the Strait of Juan de Fuca, and in particular wanted to look at winds blowing from the south, so trimmed those data to winds that were recorded as coming from between 120 and 210 degrees.  The histogram of those data suggest that extreme winds here would be those in the 18-20 kt range...

and on March 20 that buoy in the strait recorded peak average winds from the south on the order of 18 kts:

so pretty strong winds.  Again, not horribly strong from the standpoint of the available record dating back to 2004, but pretty strong.  So this leaves us with the notion that what MIGHT have been unique about this storm wasn't so much the relative magnitude of any of the individual processes at play (i.e. astronomical tides, storm surge, and wind) but rather the co-occurrence of these factors...i.e. what is the chance that you get a relatively high astronomical tide, coupled with a strong storm surge, coupled with pretty strong south winds that kick up relatively large wind waves (large by Puget Sound standards).  Taken together, maybe those things do amount to a pretty darn rare event, possibly even a 1-in-100 year event...but calculating that joint probability distribution will have to wait for a later date.