Sunday, September 16, 2012

Bottom sampling, tilted sonars, and windy days at sea

It is day number 260 and we are currently anchored in the Northeast Harbor of the Shumagin Islands. We have cancelled operations for the day due to extreme weather. Even at anchor, the ship is rolling significantly. You can barely tell that we are anchored at all. There are gusts of wind from 60-80 knots with the winds coming out of the West Southwest at 40-45 knots. The forecast for the seas is at 20ft (luckily not inside the harbor where we can safely wait out the storm).
The winds are so strong at the surface that the waves are getting picked up into the air. Mist is surrounding the Rainier. I'm happy to be on the ship and not out in this weather today.

Anchorage in Northeast Harbor


Windy day in the Shumagins

Gusts up to 80 knots inside the Northeast Harbor

BOTTOM SAMPLING
Over the past few weeks I have been on the bottom sampling boats. This requires us to go out to various locations, drop a bottom sampling tool, collect a sample (if possible), record and move to the next one. The day is spent mostly transiting. Collecting bottom samples is part of the project instructions and serves several different purposes, one of which is used for anchoring.
We use a winch to drop and retrieve our bottom samplers. This can be preferable to dropping the sampler that is attached to a line and retrieving it by hand...especially in deep waters.
Our standards for bottom sampling is as follows:
If no sample is collected after three tries, it is considered unknown. Otherwise, there are many different classifications. Most of the samples we collected included fine grey sand, broken shell, seaweed, medium to coarse sand, etc. One of our bottom samples even included a little crab scurrying about the sample pan.

The bottom samples we were able to collect in one day. The "T" symbol describes the location.


Retrieving the bottom sampler using a winch

Opening the bottom sampler

A bottom sample....we even caught a crab!

These bottom samplers can be tricky. You have to have the right touch to get them to work properly.

A good bottom sample of mostly broken shell

A great bottom sample of mostly broken shell

TILTED SONAR
Yesterday, I went out on the launch that has the 8125 tilted sonar mounted on it. We use this sonar to do shoreline work because it allows us to see further inshore without having to get too close. This is very helpful when there are unknown rocks or lots of kelp in the way. It keeps the launch safe without having to forgo collecting data.
The sonar operates a bit differently than the standard 7125 multibeam sonars (that I'm used to). We have a different computer and monitor (which tilts so we can see the sea floor better).

Tilted sonar (with a tilted monitor)

Shoreline investigation using the 8125 sonar

Shoreline

I got to see a gorgeous sunrise the second time I went out bottom sampling. We were lucky to have better weather. This is getting to be a rare thing in Northeast Alaska in the middle of September.

Sunrise in the Shumagin Islands

Sunrise before going out to do bottom sampling

Two of our launches leaving the ship for hydro operations

Beautiful morning at sea

Shumagin Islands

Here are some more wave pictures I was able to capture. Unfortunately the pictures just can't do it justice. The waves can be spectacular.

  

  

  

  

  

Waves crashing over the bow

COVERAGE
Here is the most recent coverage of my sheet and the entire project area. We are getting close to being done. This is a combination of the launches going out to collect multibeam data as well as the ship acquiring data.

Coverage on my sheet up to day 259

Coverage of our project area up to day 259

I wish I could be posting more often, unfortunately our internet connection isn't the best out here in the Shumagins. Some days we are barely connected at all.
We plan to start our transit back to Kodiak on Tuesday for a weekend inport. The transit takes about 35 hours, so we plan to get into Kodiak on Thursday.
Greetings from Alaska!

Getting into our "gumby" suits (survival suits) during an abandon ship drill

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