Byron Crump's blog

Overnight last night we anchored in the North Channel near the Saturn 01 station and cast the CTD hourly until the morning. We then moved to the south channel to begin a day of CTD casts with the goal of following a specific salinity bottom water (~15), up and down the estuary. We were guided by Joseph Zhang at OHSU who provided way points and times. For most of our casts the surface water was saltier than predicted, and the bottom water was fresher than predicted, suggesting that the forecast model is not capturing the degree of water column mixing.

We left the dock this morning at 5:30 am and headed down estuary to our first sampling station. Our goal today was to collect water samples at a range of salinities and make sure those samples do not have a lot of particles in them. This estuary has very strong Estuarine Turbidity Maxima (ETM) in its north and south channels. ETM are hydrodynamic phenomena in which river-borne particles are trapped and concentrated in the estuary as the freshwater moves through. These particles are resuspended by the tides and settle back to the bed during slack tides.

This morning we docked at the Port of Astoria to switch out some scientific crew members and to pick up our Argos drifters. Our coring team of Mouzhong Xu, Mindy Ingebretson and Paul Walczak got off the ship and were replaced with grad student Caroline Fortunato, undergraduate intern Lauren Vice, and webmaster/videographer Jeff Schilling. We made a run to Fred Meyer for some more buckets and some dry ice for transporting sediment core samples back to OHSU. We also relaxed a little. Many folks went bowling in Astoria.

After we finished sampling the La Push line we spent the night steaming back to the mouth of the Columbia to start a Feature Tracking exercise in the 'young' plume. Grant Law from the modeling team provided a list of way points/times designed to sample across a range of surface salinities within the plume, including a point just outside the plume front. This is a challenge because the plume is very dynamic and changes shape and size dramatically with the tides (see attached movies).

After completing our work on the Cape Falcon line, we spent the nighttime cruising up the Washington, casting the CTD at station along the 100m isobath all the way to LP-12 on the La Push line. We then moved inshore to LP-4 to start the La Push line. We casted the CTD at 10 stations going east to west (LP-4, 6, 9, 12, 17, 22, 27, 32, 42, 52), collected water samples at three depths at four stations (LP-6, 17, 32, 52), measured primary production at one station (LP-6), and collected sediment cores at two stations (LP-17, 52). Our team is now processing samples with confidence and ease.

Today we sampled along the Cape Falcon line, which is just south of the Columbia River Line and is, according to the CORIE forecast, awash with the Columbia River Plume. The CORIE modeling team emailed me an animation of surface salinity in this region, and we conducted CTD casts along the line until we found low salinity water.

We casted the CTD at stations along the coast up to CM-10 off Cape Meares, OR, and then went directly to station CR-4 off the Columbia River to start an offshore transect. We cast the CTD at nine stations (CR-4, 7, 10, 15, 20, 25, 30, 35, 40), and collected water samples a four (CR-7, 15, 30, 40). We also measured primary production at station CR-7, and collected sediment cores at CR-7 and CR-40. This was a full day of work and we had no major setbacks. Spirits are up, seasickness is memory, and everyone is in a smooth routine.

When the sun came up we cast the CTD at NH-55 to collect our fourth and final set of NH water samples. This site is 2880m deep, so several in the science team decided to see what that kind of water pressure does to styrofoam cups...

We then motored to Newport to drop off a seasick student before heading up the coast to do CTD casts along the 100m isobath.

Undergraduate Mindy Ingebretson and Doug Beck demonstrating an Immersion SuitWe spent a beautiful day on July 9 loading the ship and going out to lunch and dinner in Newport.