Christine Hedge, September 15, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Chukchi Sea, north of the arctic circle
Date: September 15, 2009

MST2 Tom Kruger and MST3 Marshall Chaidez retrieve a meteorological buoy on September 14.

MST2 Tom Kruger and MST3 Marshall Chaidez retrieve a meteorological buoy on September 14.

Weather Data from the Bridge 
Latitude: 730 22’N
Longitude: 1560 27’W
Temperature: 310F

Science and Technology Log 

The past few days have brought much change.  The depth of the ocean changed dramatically as we got closer to Alaska. The ocean went from depths of over 3500 meters to depths of less than 100 meters.  More birds are showing up and we are getting about 9 hours of darkness each day.  This morning at about 4 AM, the watch observed the Aurora Borealis and stars!!!  I am so jealous.

FOR MY STUDENTS: Why do you think we have more hours of darkness now? 

As we head home to Barrow, the science party is busily completing their “Cruise Reports” and making sure that their data is stored safely for the trip home.  Much has been accomplished on this trip:

  • 132 XBT deployments (measures temperature, depth)
  • 8 CTD deployments (measures conductivity, temperature, depth)
  • 5 Dredge operations and hundreds of pounds of rock samples collected and catalogued
  •  1 Seaglider deployed and retrieved
  • 2 HARP instruments retrieved and 3 deployed
  • 3 Ice buoys deployed
  • 8 Sonobuoys deployed
  • 9585.0 lineal kilometers of sea floor mapped
  • 1 METBUOY retrieved (meteorological buoy)

Coast Guard Marine Science Technicians  

MST3 Marshal Chaidez operates the winch during a dredging operation.

MST3 Marshal Chaidez operates the winch during a dredging operation.

Science parties come and go on the Healy, each doing a different type of research.  A constant for all the scientific cruises is the good work done by the Coast Guard MSTs (Marine Science Technicians). Running the winch, taking daily XBT and weather measurements, working the dredge, and helping to deploy buoys are just some of the many tasks these technicians do. The scientists could not get their experiments done without the assistance of our team of MSTs.

MST3 Daniel Purse, MST2 Daniel Jarrett, MST3 Marshal Chaidez, MST2 Thomas Kruger and Chief Mark Rieg have done a masterful job of helping the science party accomplish their goals. I asked them to tell me a little about their training for this job. Each MST attends a 10-week training school in Yorktown, VA. Most of their training involves how to clean up oil spills and inspect cargo ships which means they are usually stationed at a port. Being assigned to a ship is not the norm for an MST.  But, because the mission of the Healy is specifically science, a team of MSTs is essential.

MST2 Daniel Jarrett rigging the crane.

MST2 Daniel Jarrett rigging the crane.

Personal Log 

My commute to work is different lately. We have about 9 hours of darkness each day. It gets dark around midnight and stays dark until about 8:30 in the morning.  So, walking the deck to the science lab is a bit of a challenge at 7:45. It will be strange to drive to work in a few days! On September 16th, we will depart the Healy via helicopter if all goes according to plan.  It will be strange to be on land again.

We will be back in Barrow, AK on September 16th. I cannot believe that our expedition is almost over.  I have learned so much from the members of the science party and the crew of the Healy. They have been very gracious and patient while I took their pictures and asked questions. Now comes the task of sharing what I have learned with folks back home.  I know one thing for sure; the Arctic is no longer an abstract idea for me. It is a place of beauty and mystery and a place some people call home.  I hope to convey how important it is that we continue to study this place to learn how it came to be and how it is currently changing.

Jon Pazol and I next to the bowhead whale skull in Barrow. When we return to shore the bowhead hunting season will have started.

Jon Pazol and I next to the bowhead whale skull in Barrow. When we return to shore the bowhead hunting season will have started.

Thanks to the folks at NOAA Teacher at Sea, Captain Sommer, and chief scientists Larry Mayer and Andy Armstrong for allowing me to take part in this cruise.  You can be sure that I will be following Arctic research and the adventures of the Healy for many years to come.

Christine Hedge, August 13, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Chukchi Sea, north of the arctic circle
Date: August 13, 2009

Weather Data from the Bridge  
Long: 14809.54199W
Lat: 78017.31641N
Air Temp: 31.08 0F

Science and Technology Log 

A CTD, above, is much bigger than an XBT, which I’m holding in the picture below.

A CTD, above, is much bigger than an XBT, which I’m holding in the picture below.

Sound waves travel at different speeds through different substances.  If you look up the speed of sound in air you will find it to be about 300 meters/second, in water 1500 meters/second.  But these numbers are not constants.  In water, the temperature, the amount of salt, and the pressure can all impact how fast sound waves travel.  In other words, all water is not created equal.  Our mapping mission depends on data collected from bouncing sound waves off the sea floor.  In order to get an accurate image of what the sea floor looks like and how deep it is – we need to measure precisely how fast the sound waves are traveling.  This means we need to have a handle on any variable that might change the speed of the sound waves.  Measuring the speed of sound in the water column is an important part of data collection for accurate mapping.

So, how does the Healy measure the speed of sound? Sometimes we use a Conductivity-Temperature-Depth instrument (CTDs).  The ship needs to be stationary to deploy these instruments so they don’t happen very often while we are cruising. CTD measurements record conductivity of the water, which gives us the salinity (how much salt is in the water), temperature, and the depth at which these measurements were taken. Four times a day instruments called Expendable Bathythermographs (XBTs) are deployed off the moving ship. These XBTs measure the temperature as the device travels through the water. As pressure increases, (the deeper you go) the speed of sound increases. As temperature decreases, the speed of sound decreases. Four times a day the Healy science crew gets new data so that they can determine more precisely the speed of sound and therefore interpret what the sound waves are telling us.

Here I am deploying the XBT into the Arctic.

Here I am deploying the XBT into the Arctic.

Today, MST-2 (Marine Science Technician) Daniel Jarrett let me participate in the deployment of an XBT. As the device travels through the water it sends back temperature data from different depths to a computer on board.

The data travels through a very thin copper wire attached to the instrument. A graph of this data is observed and that information is used to create a profile of the speed of sound in that part of the Arctic Ocean at that moment in time.

Personal Log 

All the things I do at home also have to be done on board ship. I eat, sleep, shower, exercise, and do laundry. The food is excellent so far. I love not having to cook or plan meals.  There is fresh fruit, a salad bar, and a huge hot breakfast every day. It will be a rude awakening when I return home and have to plan and cook meals again! My daily routine does not involve much physical activity and I worry about gaining weight while on board. In order to stay in shape, it seems everyone uses the gyms or runs on deck. I have been working out on the treadmill or elliptical every day faithfully to avoid a severe weight gain.

Was the data good? Did the deployment work?

Was the data good? Did the deployment work?

The laundry and all other facilities are really nice. I have a 25-year-old washer/dryer at home and was pleasantly surprised to find state of the art, low-water-usage, front-loading washers on board the Healy. From what I can see the United States Coast Guard is working hard to become a “green” organization.  Trash is separated and recycled when possible. People are encouraged to reduce their water usage. Extreme care is given to filtering and recycling wastewater and any kind of oil or lubricants. It is great to see the amount of thought and energy that is being put into helping the community on board the Healy to “walk lightly” on the Earth.

The Healy is very careful to treat the arctic with care

The Healy is very careful to treat the arctic with care