Sure, When Hood Canal Freezes Over

Looking across the ice towards the Great Bend

Okay, so no one says that but they might as well... I mean, whoever heard of a body of salt water this far from the poles freezing? That’s what was going through my head as I drove our 20’ aluminum boat into the icy sheet last winter.

It started out as a normal, albeit cold, field day for the Oceanic Remote Chemical Analyzer (ORCA) team.  We launched the M/V Mackinaw at Twanoh State Park and drove out to our research buoy in Lynch Cove to replace the CTD package and repair the winch control box.  We thought we were prepared for a cold day on the water, armed with extra layers, beanies, scarves and multiple pairs of wool socks, but then the snow started.  I always seem to forget how difficult it is to do precise, mechanical work on cold metal instruments with cold metal tools, while constantly being splashed by cold, cold water.  The work was taking much longer than anticipated with all of this cold on cold.  When we eventually finished the required maintenance I pointed the boat toward the ORCA Hoodsport buoy where we were scheduled to work on the router.  As we turned around Sisters Point I noticed a definite line on the water surface ahead of me.  “Weird, that looks just like…”  CRUNCH!!!  

Standing on the bow of the M/V Mackinaw as we try to push our way through the ice

Before I could even finish my thought we were startled with a sudden crash as the Mackinaw tried pushing through a sheet of ice.  I slowed down and carefully backed us out through the path we had just cut, and then motored along the margin to see if there was any way through.  No luck.  A flock of seagulls stood on the ice and watched us while we made a call and sent photos to our incredulous supervisor at the University of Washington.  There was no way we’d be able to continue.  We couldn’t see the end of the ice sheet and even if we made it through we’d lose too much daylight to get any work done.  After a few more minutes playing with the chunks of ice that had broken free of the sheet, we headed back to Twanoh to get our boat out of the cold water.

Snapping some photos while we wait for confirmation to call it a day

Encountering ice in Hood Canal surprised our group but apparently it’s not that strange.  Fresh water that flows from the Skokomish River into Hood Canal tends to float on top of the denser salt water, creating a thin fresh layer.  When temperatures drop this layer can freeze, just like any body of fresh water.  If temperatures stay low for long enough, the ice sheet can reach from shore to shore like we witnessed... I’ve even heard stories of people driving wagons across the canal in previous centuries!

Holding up a piece of our Hood Canal ice sheet

Estuarine Circulation through Hands on Learning

Parker MacCready from the UW School of Oceanography demonstrates injecting dyed fresh or saltwater in various depths and locations of the "Puget Sound"

Tucked away in a beautiful brick building on a canal at the University of Washington (behind a free standing whiteboard in the University of Washington's Old Oceanography Building) is an impressive and powerful visualization tool. A to-scale model of the Puget Sound was built in 1950 by the School of Oceanography and has been used to research and teach tidal and circulation characteristics in our complex estuary.

Water enters the Puget Sound from the Pacific Ocean through the Strait of Juan de Fuca, is mixed up in Admiralty Inlet, then pours over shallow sills into four major fjord-like basins.  Some of these are well mixed and regularly circulated while others are stagnant and stratified.  The system is further complicated by tides, freshwater input from rivers the seasonal appearance of cold, salty water from upwelling along the coast.

Dyed freshwater injected at the "Duckabush River" output forms eddies on the surface as it slowly moves north out of "Hood Canal"

This model is so lasting because it attempts to take some of these complications into account.  For example, a tide machine near the model's "ocean" moves water in and out of the system, taking about one minute to complete each tidal cycle.  Tubes beneath the model constantly trickle freshwater at roughly the same rate and location as main rivers.  The bathymetry of the Sound is represented and exaggerated to allow for the viscosity of the water at this scale.

Students are able to inject either fresh or saltwater mixed with blue dye anywhere in the system and observe what happens.  This week a group of students noticed that fresh water stayed near the surface and tended to move out of the system, toward the "ocean," while dense salt water sank.  The deep salty water would then slowly move into the system or get stuck in various deep pockets like in Dabob Bay, Carr Inlet or just west of Deception Pass.  They also noticed a large difference between the different freshwater inputs.  A few drops of dyed water on the "Skagit River" dissipated into Whidbey Basin almost immediately while dye at the "Snohomish River" input remained for the entire class period.

A bird's eye view over "Whidbey Island" shows fresh water from the "Skagit River" quickly dispersing into the basin while dense salt water is trapped in a deep pocket just outside of "Deception Pass"

ORCA Field Day: Solar Panel Installation

Maintaining the Oceanic Remote Chemical Analyzer (ORCA) buoys requires semi-regular field days for UW Field Engineers.  Today, Gretchen Thuesen and Rachel Vander Giessen head out to install a solar panel on the Dabob Bay buoy.  They spend the days leading up to the field day getting supplies, instruments and electronics ready, lining up an appropriate vehicle and checking the tides and wind forecasts.  This morning they do one last wind check then meet at the Ocean Science Building to load the truck before catching an early ferry to Bremerton.  From there they drive to Belfair where the M/V Mackinaw is stored at the Pacific Northwest Salmon Center.

Hitching the M/V Mackinaw and trailer to the truck and saying good morning to PNWSC staff

The trailer is hitched to the truck and the engineers head north, towing the 20’ boat over the Hood Canal Bridge to Quilcene where they’ll carefully launch it in the narrow marina and motor out to the buoy.

The boat and buoy have to be lined up just right for transferring the heavy solar panel

Maneuvering heavy equipment from the boat to the buoy is difficult and time consuming… calm winds help by allowing the boat to be tied up on the correct side of the buoy regardless of wind direction.  The solar panel and frame housing is large and heavy and has to be carefully laid out on the boat so that it can be transferred to the buoy without incurring damage.  Rachel holds it in place on the buoy platform while Gretchen secures it with U-bolts.

Gretchen preps hardware and tools for the solar
panel installation

Dabob buoy with a newly installed solar panel

Eventually, we get the hardware installed and all of the electronics wired up.  Now Dabob is equipped with two 75 W solar panel that will recharge the battery bank, supplying predictable power to the oceanographic instrument system.

A Day at Sea

Members of the science team help the Resident Technician retrieve the CTD rosette aboard R/V Melville

My alarm goes off at 0600 and I lay in my rocking berth listening to the jingle bell sound of the Chirp Sonar.  Swinging through the main lab on the way to the mess hall I glance at the white board for updates and messages.  Coffee is enjoyed on the fantail while searching for whales with some of the crew and science team.  I do a run through of the morning's sampling supplies before heading back into the mess hall at 0730 for a quick breakfast of bacon, eggs, potatoes and fresh fruit.  We then prep the rosette and computer for the 0800 CTD cast.  We're scheduled to sample a line of stations along the coast so this will be the first of three casts today.  Radio checks between bridge, winch, lab and deck, then the rosette goes over the side and down to a predetermined depth as we watch the PAR plot for the chlorophyll max.  Then the winch brings the rosette up in increments and all niskin bottles are fired, collecting water at different depths.  

Gloves are important when taking water samples to avoid contamination

Once the rosette is recovered and secured on deck, the science team circles around it in waves, taking seawater samples to be analyzed for things like dissolved oxygen and carbon, nutrients and chlorophyll.   Once sample collection is complete, everyone gets busy at their stations in the main lab, running through their different analyses while the ship motors on to our next station.  

Maintaining the deionized water system in the analytical lab

Running water sample analyses in the main lab

The rest of the day follows this pattern: CTD cast, water collection and sample analysis in the lab with an 1130 lunch break. A day at sea revolves around mealtimes so the quality, quantity and diversity of options is important... fortunately we're well taken care of and on today's menu is chicken fajitas.  Members of the crew take their coffee breaks at 1000 and 1400 and are an endless source of stories if you're able to step away from your lab bench.  Some people are able to wrap up their work by dinner at 1700 and we all settle down in the library afterwards for a brief science meeting.  The chief scientist gives an idea of how the big picture is forming and where we're headed from here.  It also gives us the opportunity to describe our individual roles in the expedition and learn about different areas of research.

Today was a light sampling day so we take the opportunity to start a load of laundry, clean our cabins or get caught up on paperwork.  We meet on the forward deck to watch the sunset and enjoy an impromptu guitar solo.  The rest of the evening is spent playing cards in the mess hall or watching a movie in the lounge.  Working at sea is more tiring than you'd expect so everyone heads down to their berths early for a good night’s sleep.

Relaxing after a long day