Tuesday, June 9, 2015

Back out to the Spit

The view from the end of Dungeness Spit

For the third year I was able to arrange with the US Fish and Wildlife Service to collect beach morphology data on Dungeness Spit for my shoreline monitoring program. This is such a special survey to me - its the most difficult logistically, but provides a chance to collect some data on what is really a spectacular coastal feature:

A view of the lighthouse from the end of the Spit, with the Olympics in the background.

Spits are really such important coastal features. In the case of Dungeness Spit it creates a very unique and productive shallow water habitat in its lee. And its "sister", Ediz Hook, creates what many argue is the best harbor in the region. In my view, we simply need to do a better job at understanding what makes these sorts of coastal features work. One surprise, at least based off looking at the preliminary data, is that the end of the Spit appears to have retreated a bit, at least over the last few years:

Again, these data are very preliminary, and just one profile doesn't tell the whole story...but given the average rates of growth reported by Maury Schwartz this is an interesting finding. Part of the story could be related to the migration of the top of the Spit, but it clearly is a complicated story. These profiles cutting through the bulge at the end of the spit for example, suggest the possibility (again, using the caveat that just one set of profiles per year doesn't a convincing story make) that erosion on the seaward side of the spit was associated with accretion on the landward side between 2012-2014:

But that pattern didn't hold up in 2015.

More to come - I will head out to finish the long skinny part of the Spit later this month or next, and then hopefully continue annual surveys for at least another two years.

Wednesday, May 27, 2015

Getting nerdy with sea level in the Pacific Northwest

A few weeks back I gave the webinar above on a new approach we are using to project future sea level in a climate change adaptation planning project I am involved in focusing on Clallam and Jefferson Counties in Washington State. The approach takes advantage of a new synthesis of sea level rise projections published last year.

Despite struggling with how to most effectively communicate probabilistic sea level rise projections, I'm really liking this new approach, and its got me thinking about how to do an even better job of incorporating and communicating the current and future hazard related to sea level processes. In the webinar, though, I highlight a few outstanding needs - gaps in research or data needs that are limiting our ability to be as rigorous we can possibly be with assessing contemporary and future hazards related to sea level and coastal impacts.

As an example, consider that these sea level rise projections are meant to get at the "still water level" (i.e. ignoring waves). In general we've viewed that as an okay first-order approximation of the hazard in the inland waters of Washington State...but is it?

First consider the photo above, which comes from Cliff Mass's Weather Blog (check out the specific blog here), but that he attributes to the West Seattle Blog. This photos was taken on 17 December 2012, when the water level, as measured by the NOAA tide gauge in Seattle, reached 14.47 feet relative to MLLW:

This water level was just shy, by a whisker (0.01 feet to be exact) of the record water level measured in Seattle on 27 January 1983.

Next consider this photo, taken at the same exact spot by Melissa Poe of Washington Sea Grant on 29 November 2014:

On this day, still water level reached just 13.11 feet:

Well shy of the near record water level of 14.47 feet associated with the event from 17 December 2012...yet the flooding extent is essentially the same. The obvious difference? A local wind storm generating waves:

So what this tells me is that the data that we derive from tide gauges, and that we use to assess the coastal flooding hazard now and in the future only tells us part of the story, and we need better information on waves in order to take things to the next level. This is nothing new, Peter Ruggiero and others have been telling us for years that we need to account for "total water level"...including the influence of waves. But largely that message has focused on the substantially more energetic wave climate of the outer coast of the Pacific Northwest. Clearly we need to account for waves in the inland waters as well. Now, if only we had data...

Wednesday, April 29, 2015

Coast Nerd video

Last weekend was the 2nd Annual River and Ocean Festival, held in Forks, WA in association with the Washington Coast Clean-up.

Make sure you make room for the 2016 film festival in your schedule!

I help to organize this event because I think we are entering this great age of small-scale film-making, enabled by digital technologies. And that means that, more and more, we are seeing perspectives and views into other peoples lives and experiences that we've never had before. The River and Ocean Film Festival is designed to showcase films about the west end of the Olympic Peninsula, but I've also been tracking films about coastal science and hazards. A few that have come up lately:

Here is a nice little series I found just last night, by the St. Petersburg (Florida) Coastal and Marine Science Center of the USGS. I love this!:

While I am a giant fan of the USGS Coastal and Marine program, I think that from the standpoint of nerdy videos about coastal geology and geomorphology, that this video series from Ireland takes the grand prize. Here is an example:

I love this stuff!

A bit closer to home, is this piece by Oregon Sea Grant focused on the coastal effects of climate change, part of a series (find them all here):

and there are also some really nice coastal videos at the Science Earth youtube channel. Here is an example:

And then we get into the one-offs. As an example, here is an interesting film by The Verge focused on design strategies for protecting Manhattan after Hurricane Sandy:

Thursday, April 23, 2015

Rialto Beach

Its been a while...

Had the chance to survey Rialto Beach earlier this week, on the coast of Washington in Olympic National Park, as part of my shoreline morphology monitoring program (which is, by the way, looking for a better name...should you have any ideas). And I decided to post about it because...MAN, WHAT A BEACH! Rialto is so very cool...every time I go out there I am blown away by its morphology and the degree of variability it exhibits.

The first thing you notice at Rialto are logs. Does this beach ever have logs (see photos above)! And these aren't small logs either - these are massive old growth trunks grounded in the upper intertidal. These things are definitely influencing shoreline morphology and evolution...they must be...but exactly how isn't totally clear to me yet.

The next thing that always strikes me about Rialto is the evidence of erosion everywhere...mostly in the form of dead trees:

The odd thing, though, is that based on survey data from the last few years, it doesn't look like Rialto is eroding really at all over shorter, annual, timescales (though it is subject to seasonal variability). That suggests to me the likelihood that this shoreline is pretty subject to erosion related to relatively infrequent El Nino winters, or perhaps the once-or-twice-a-century extreme storms. I know that there have been big changes out there within recent living memory - I would love to hear any stories...

But the other thing I've started to really take note of at Rialto are exposures of what appears to be some base strata that the ocean is cutting into:

It would be interesting to date some of these exposures, and try to work out what they tell us about the evolution of the shoreline on the coast of Washington over longer time-scales.

Finally, I am always blown away by the ocean's power on display at Rialto:

Above, for example, is a photo of a sizeable small boulder wedged into the crook of a root wad, which is itself buried in the beach substrate. Now its entirely possible that this rock travelled with the root wad, but it sure looked like the thing had been forcibly jammed into place, and waves have been known to move bigger. The waves at Rialto always seem more powerful to me as compared to just across the river in La Push, which I've attributed to perhaps the off-shore bathymetry, or the beach orientation. Regardless, this was an indication to me of the forces at work on this beach.

Thursday, March 5, 2015

Second Beach

The view from Second Beach, Olympic National Park, this weekend

Had the opportunity to visit Second Beach over the weekend, and survey First Beach at La Push a few days ago with students from the Quileute Tribal School and Forks High School. Its been a beautiful stretch of weather, and the coast is the right place to be at times like these.

A bedrock exposure at the south end of Second Beach, completely coated with Aggregating Anenomes (Anthopleura elegantissima)

A few observations from Second Beach...

I was struck at Second Beach by the volume of the beach...it looked like the beach had accreted substantially since the last time I was there a few months back. Even at a mid-level tide the beach was broader than I remembered:

On the upper beach, many large logs were partially buried by sand:

Large logs at Second Beach partially buried by fresh deposition

Is this a localized episode of accretion at Second Beach? Or is there something about the weather recently (relatively mild, small waves, etc.) that has pushed sand up into the intertidal? I'm curious now to work up our data from First Beach, and see how the profiles look...

Thursday, January 29, 2015

Sampling the sea floor

Guy Gelfenbaum and Jackson Currie, both with the US Geological Survey, use a sediment grab off-shore of the Elwha River delta.

One of the fundamental data types used to track change in the coastal zone adjacent to the Elwha River mouth are sediment samples. Grain size data play a central role, for example, in our recently published paper documenting physical changes to the coastal environment in the first two years after dam removal.

Yesterday, associated with regular topography/bathymetry surveys of the Elwha River delta, I went out to help dredge up yet more dirt from the ocean floor. Check it out:

The day turned out to be pretty nice, with beautiful water conditions, so all in all not a bad way to spend a day...plus every sample we pulled up added a bit to our understanding of how sediment is moving around in the coastal environment. On top of it, we got to observe a veritable feeding frenzy occurring right off the river mouth, with possibly ~100 Harbor seal and California sea lions feeding (perhaps on some of the fish species observed just a few days earlier?) just a few feet outside the river mouth.

Tuesday, January 6, 2015

A Fall Warm Water Pulse in the Strait of Juan de Fuca

Students from this year's oceanography class construct their mooring

For the past three years my oceanography class at Peninsula College has built and deployed moorings that measure, amongst other things, water temperature around City Pier in Port Angeles Harbor. The deployments are always about a month long, and always take place around the same time...usually mid-October to mid-November.

HOBO pendants, the data collection workhorse for my class's moorings

The moorings are built around HOBO pendants, which are placed to measure both surface water temperature, and "deep" water temperature...up to about 25 feet deep in this part of the Harbor.

Mooring deployment locations around City Pier

Here is the interesting observation from this year: We captured a really dramatic spike in water temperature this fall. I'm going to show data from the deepest water HOBO available at Station D, off the very end of the Pier, simply to illustrate that this wasn't just a surface warming phenomenon. This HOBO sits at a depth of about 20 feet relative to MLLW. Here are the data from 2012 and 2013. You will note that the 2012 deployment was only 2 weeks long:

In 2014 here was the pattern (the green line). Hopefully the difference is obvious:

But in reality, given the short record in 2012, we are working with only two years of data here - not ideal. So lets turn to surface water temperature measures from the Port Angeles tide gauge to try to get a sense of how anomalous this might be. First off, here is the typical annual pattern, based on data since 1998:

This takes water temperature data from each year (hourly observations) and plots them against the day of the year. I've colored all these years the same - the key take away is that in the fall the typical pattern is to see a decline in water temperature as winter sets in.

2013 was a bit different, in that there was a one-week pulse of relatively warm water recorded in the harbor in October (around Day 275; and actually one in July as well around day 180):

At the time I thought these two pulses were very interesting (and still do). But this year's fall pulse, the one we picked up with our class HOBO's, lasted much longer and was warmer (the red line between about Day 280 and 330):

That bulge between about Day 280 and 330 is warmer, by about 2 degrees Celsius, than the "usual" warm temperature at that time of year. The only other year that exceeds it? The 1997 winter, during a strong El Nino (shown here in purple):

Here, the pulse of warm water in the harbor occurred a bit earlier in the fall, but looks very similar in terms of its magnitude and duration. The interesting thing is that NOAA currently has us on an El Nino Watch, and suggests that El Nino conditions still aren't present. Interestingly, though, they note that much of the Pacific is warmer than average, but its the atmospheric El Nino conditions that haven't materialized. No matter which way you cut it though, no once is calling this a strong El Nino like the one that materialized in Spring 1997.

Another way to look at this is to look at the monthly average temperature from the Port Angeles tide station:

So in this case the thinner line is the monthly average temperature - you can see the seasonal pattern in there quite clearly. The green thicker line is the anomoly from the average monthly temperature, in degrees celsius, and November 2014 is the peak in that green line just shy of 2015. It is the highest temperature anomoly since the 1997-1998 El Nino.

So what is going on? I'm not really sure...and would love to figure it out. Contact me if you can help me understand.