Category: Christine Hedge

Posted on

Christine Hedge, August 20, 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: Beaufort Sea, north of the arctic circle
Date: August 20, 2009

Weather Data from the Bridge  
Lat: 80.570 N
Long: 151.320 W
Air Temp: 29.210 F

Science and Technology Log 

The science computer lab is where the data is observed. Processors clean the data of all the extraneous noise and spikes. Not every beam is returned and some take a bad bounce off a fish, chunk of ice or a bubble.
The science computer lab is where the data is observed. Processors clean the data of all the extraneous noise and spikes. Not every beam is returned and some take a bad bounce off a fish, chunk of ice or a bubble.

The Healy is collecting bathymetric data on this trip.  Bathymetric data will tell us how deep the ocean is and what the terrain of the ocean floor is like.  Less than 6% of the floor of the Arctic Ocean has been mapped.  So, this data will help us to learn about some places for the very first time.  The word bathymetry comes from the Greek – bathy= deep and metry = to measure.

NOTE TO STUDENTS: If you learn Latin/Greek word parts you can understand almost any word! 

How Do We Collect This Data? 

There are two main devices the Healy is using to measure the depth to the seafloor.  One is called the multibeam echosounder. It sends a beam of sound, which reflects off the bottom and sends back up to 121 beams to a receiver. By measuring the time it takes for the sound to return the multibeam can accurately map the surface of the sea floor.  This allows the multibeam to “see” a wide swath of seafloor – kilometers wide.  The other device is bouncing a single beam off the bottom and “seeing” a profile of that spot. This one is called a single beam echosounder or sub-bottom profiler. The single beam actually penetrates the sea floor to show a cross-section of the layers of sediment. Both are mounted on the hull of the ship and send their data and images to computers in the science lab.

What Does Mrs. Hedge Do? 

This screen shows the multibeam bathymetry data. Depth is measured over a swath about 8 kilometers wide on this particular screen. Purple is the deepest (3850 m) and orange is the most shallow (3000 m). You can see that for most of this trip we were on flat abyssal plain and then we hit a little bump on the sea floor about 450 meters tall.
This screen shows the multibeam bathymetry data. Depth is measured over a swath about 8 kilometers wide on this particular screen. Purple is the deepest (3850 m) and orange is the most shallow (3000 m). You can see that for most of this trip we were on flat abyssal plain and then we hit a little bump on the sea floor about 450 meters tall.

The science crew takes turns “standing watch”. We have 3 teams; each watches the computers that display the bathymetry data for an 8-hour shift. My watch is from 8 am until 4 pm.  We need to look at how many beams are being received and sometimes make adjustments.  Traveling through heavy ice makes data collection challenging. We also need to “log” or record anything that might impact the data collection such the ship turning, stopping, heavy ice, or a change in speed. When we are going over an interesting feature on the seafloor, our job is engaging. When the seafloor is flat, the 8-hour shift can seem pretty long!

How Did People Do This Before Computers? 

Until the 1930’s, the depth of the ocean was taken by lowering a lead weight on a heavy rope over the side of a boat and measuring how much rope it took until the weight hit the bottom. This was called a lead line.  Then the boat would move and do this again, over and over.

Another bear was spotted from the Healy. Photo Pat Kelley.
Another bear was spotted from the Healy. Photo Pat Kelley.

This method was very time consuming because it only measured depth at one point in time.    Between soundings, people would just infer what the depth was.  Using sound to measure depth is a huge improvement compared to soundings with a weighted rope.  For example, in 100 meters of water, with a lead line 10 soundings per hour could be obtained.  With multibeam at the same depth, 1,500,000 soundings can be obtained per hour.  Mapping the ocean floor has become much more accurate and precise.

FOR MY STUDENTS: Can you think of other areas of science where improvements in technology lead to huge improvements and new discoveries? 

Personal Log 

When a polar bear is spotted, the deck fills with hopeful observers.
When a polar bear is spotted, the deck fills with hopeful observers.

Last night, there was an announcement right after I went to bed that polar bears had been spotted.  I threw on some clothes and ran outside.  There was a female and cub 2 kilometers away.  With binoculars, I could see them pretty well.  The adult kept turning around and looking at the cub over her shoulder. I suspect, the cub was being told to hurry up!  When a bear is spotted, the deck of the ship fills up with hopeful observers no matter what time of day it is.

FOR MY STUDENTS: I heard that the old polar bear at the Indianapolis Zoo died recently. Will there still be a polar bear exhibit at the zoo?  What are the plans for the future? 

Posted on

Christine Hedge, August 19, 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 19, 2009

Weather Data from the Bridge   

Brittle star
Brittle star

LAT: 810 23’N
LONG: 1560 31’W
Air Temp: 28.27 0F

Science and Technology Log 

My fellow teacher at sea, Jon Pazol, and I wonder, “What kind of brittle star is this?” We think it is a Gorgonocephalus cf arcticus.
My fellow teacher at sea, Jon Pazol, and I wonder, “What kind of brittle star is this?” We think it is a Gorgonocephalus cf arcticus.

There isn’t much biology to be done on this cruise.  Our mapping mission is the main focus.  But, living things find a way of working their way into the picture.  We have a marine mammal and a community observer on board looking for whales, seals, polar bears, sea birds and other Arctic animals. Yesterday, a small Arctic Cod found its way into the seawater pipe in the science lab. And a few days ago, when the HARP instrument was pulled up, there was a brittle star attached to it. Jon Pazol (the ARMADA Teacher at Sea) and I are both biology types and we got excited about the opportunity to identify this creature from the Arctic Ocean.

Personal log 

Yoann, a student from France, enjoys his first corndog
Yoann, a student from France, enjoys his first corndog

I did not grow up in Indiana and have avoided eating a corndog until now.  Yoann Ladroit (from France) and I (from Connecticut) had our very first corndogs for lunch yesterday. We have enjoyed many different types of food on the Healy. Imagine stocking a ship with enough food for 120-130 people for months in the Arctic. When the Healy left Seattle they had a food inventory valued at $300,000. Ideally, this ship leaves port with enough food for a year. This is more than most Coast Guard cutters carry – but the Arctic is a unique place.  In other oceans, cutters can pull in to port and purchase fresh supplies. In the Arctic there are few ports and where there are ports – the food is VERY expensive. The Healy needs to be prepared to feed the crew, just in case they get beset (stuck in ice). So, they have staple foods ready for an emergency situation.

A forklift carries food supplies to the Healy
A forklift carries food supplies to the Healy

In Barrow, the Healy picked up many forklifts full of fresh produce and eggs. This will be the last fresh produce we get until September 16th when we return to shore. The Healy is one of the newest ships in the Coast Guard and has spacious facilities in the galley (kitchen) and the mess decks (dining room).  There are huge refrigerators, storage rooms and freezers for food. The gleaming stainless steel galley has computerized ovens with probes that sense when the food has reached the correct temperature and a huge and speedy dishwasher. As a newcomer to the ship we were warned about the powerful microwave oven, which heats anything in 10 seconds and garbage disposal (affectionately called the Red Goat) which grinds up all food waste instantly.

This area, called the mess, is where we eat our meals.
This area, called the mess, is where we eat our meals.

We eat in the mess decks.  Our mess decks are twice the size of those on other Coast Guard cutters.  Meals are served 4 times each day. Breakfast, lunch, and dinner are served at the regular times.  Since people work 24/7, a fourth meal called Mid-rats (midnight rations) is served each night at 11pm.   One of the interesting features in the mess decks is the operating room set up over one of the tables. Although the Healy has a state of the art sick bay, what if the sick bay was unusable because of a fire or some other crisis? It seems that in a mass casualty situation, the mess decks doubles as a medical space, which would be used to tend to wounded personnel.

Posted on

Christine Hedge, August 18, 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 18, 2009

Weather Data from the Bridge   
Lat: 800 32’N
Long: 1540 04’ W
Temp:  28.720 F

Science and Technology Log 

Mrs. Hedge fills the weather balloon
Mrs. Hedge fills the weather balloon

Twice each day, AG1 (Aerographers mate 1st class) Richard Lemkuhl launches a weather balloon. Today, at 6 AM I assisted with the launch. The balloon is filled with helium and attached to a device powered by a 9-volt battery. The weather balloon sends back temperature, pressure, and humidity data along with GPS derived winds to a radio receiver on the bridge of the Healy. This profile of the atmospheric conditions can be injected into global weather models to help predict the weather. On the Healy we use this information for flight operations (the helicopter). Helicopters, ships, and planes all need current weather conditions to navigate safely.  Data from weather balloons can help determine if there might be icing, turbulence, wind driven ice or the possibility of thunderstorms.

FOR MY STUDENTS: All kinds of scientists use models to help explain, predict, and understand the world around them. Can you think of a model you have used in science? 

Radio Receiver on the bridge of the Healy
Radio Receiver on the bridge of the Healy

AG1 Lemkuhl works for the Naval Maritime Forecast Center in Norfolk, Virginia. He is part of a group of U. S. Navy personnel on board the Healy to better understand how to operate Navy vessels in the Arctic. The dynamic weather patterns he experienced as a child in Oklahoma sparked his interest in meteorology.  His very first weather balloon was launched in 8th grade under the watchful eyes of Mrs. Stevens, his science teacher in Clarksville, Tennessee. AG1 enjoyed learning about Earth Science as a middle school student, which lead to studying geography and climatology in college.  The Navy has added to his education and after a year of school he is currently an Assistant Operational Meteorologist.

FOR MY STUDENTS:  What have you studied in school that has sparked your interest? 

Personal Log 

AG1 Lemkuhl holding the weather balloon instrument
AG1 Lemkuhl holding the weather balloon instrument

Yesterday the sun came out and the sky was blue.  What a difference that blue sky made!  There isn’t much color in the Arctic – especially when it is foggy.  The inside of the ship is tan. The ice and sky are white. Blue sky brought more people out on deck just to enjoy the color change.  We also saw more seals out on the ice. Could it be that they like to bask in the sun as well?

Today, as we backed and rammed through 2.5 meters of ice, I saw my first fish!  They were small, about the size of my palm.  Could these be the Arctic Cod I have read about??

FOR MY STUDENTS: Look at my current latitude.  What day will the sun finally set at this latitude???

AG1 Lemkuhl shows Mrs. Hedge how to launch a weather balloon.
AG1 Lemkuhl shows Mrs. Hedge how to launch a weather balloon.
Blue Sky in the Arctic! This is the CCGS Louis S. St. Laurent. The Healy is breaking ice for her.
Blue Sky in the Arctic! This is the CCGS Louis S. St. Laurent. The Healy is breaking ice for her.
Posted on

Christine Hedge, August 16, 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: Beaufort Sea, north of the arctic circle
Date: August 16, 2009

Weather Data from the Bridge 
800 6.28’N 1400 33.69’W
Temp: 32.40F
Conditions: low visibility

Science and Technology Log

Blue sea ice with red reflected from the Healy
Blue sea ice with red reflected from the Healy

FRAZIL, NILAS, GREASE ICE, PANCAKE ICE, BRASH, AND SHUGA – These are just a few of the sea ice vocabulary words I have been learning. Ice observers and ice analysts are important people to have around while operating a ship in the Arctic. Depending on the situation and the ship, observations can be made by looking at the ice from the ship, from satellite imagery, from the air in a helicopter, or from actually walking out onto the ice and measuring the thickness. On the Healy, we are using ship-based and satellite imagery observations.

HOW THICK IS IT? 

The ice we are plowing through today is about 0.7 – 1.2 meters thick. In general, flat first-year ice is between 0.3 – 2.0 m thick, although it can get much thicker with ridging. Flat second-year ice can be up to 2.5 m thick. Multi-year ice is at least 3 m thick but can be more than 15 m thick.

WHY IS SOME OF THE ICE BLUE? 

Seawater is about 3.5% salt, but first-year ice has an average salinity of only about 0.5%.  As the sea ice grows it rejects most of the salt in the seawater from which it forms.  The ice with less salt reflects more light and air bubbles form as the ice ages.  This causes more light to scatter, producing a deeper blue color over time.

HOW IS ICE CLASSIFIED? 

Experienced ice observers look at 3 basic parameters:

1) Concentration – how tightly the ice is packed 

This is reported in tenths. Less than 1/10th ice is basically open water.  The higher the number, the more tightly packed the sea ice.  At 10/10ths the ice is considered “compact”.

2) Form – the horizontal shape and dimension of the pieces of ice 

These have specialized names and ranges of size.  For example, a brash is about the size of a bicycle. Pancake ice is circular pieces of ice, with raised edges that look like giant lily pads or pancakes.

3) Stage of Development – direct observation of the age and structural  characteristics 

The three major classifications are first-year ice, second-year ice, and multi-year ice. Structural characteristics can include things like thickness, color, ponds or melt water on top, ridges or hummocks.

WHY DOES ICE CHANGE AND GROW? 

sea ice with ponding
Sea ice with ponding

Classifying ice by stage of development is really interesting.  What sets the different classifications apart (first-year, second-year, multi-year) is the growth and aging of the sea ice.   Ice grows in the fall and winter during the freezing cycle.  Ice decays during the spring and summer during the thawing cycle. The amount of thawing that happens in the summer determines how much first-year ice survives to become second-year ice and how much second-year ice survives to become multi-year ice.

HOW IS CLIMATE CHANGE IMPACTING SEA ICE? 

Drastic changes in the condition and amount of Arctic sea ice have been observed over the past few decades. The least ice extent ever was observed in 2007.  This can mean more dangerous conditions for ships to sail in a region where variable and hazardous ice conditions still exist year round.

Personal Log 

Bundling up for the Saturday night movie
Bundling up for the Saturday night movie

Different movies play every day in the lounge spaces of the ship.  When the crew and scientists have time off they can kick back and relax with their friends.  On Saturday night, there are two special social events for morale boosters. There is bingo, and a movie on the big screen projected in the helicopter hanger. Everyone dresses in their warmest gear, camp chairs are set up, and popcorn, candy, and soda are provided. It is a kind of Arctic Drive-in experience.  Last night, we watched Star Trek. Of course, when the movie was over we walked out into bright daylight even though it was 10pm.

Posted on

Christine Hedge, August 14, 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: Beaufort Sea, north of the arctic circle
Date: August 14, 2009

Weather Data from the Bridge   
800 3’N 1450 42’W
Temp: 310 F Light, fine snow

Science and Technology Log 

The coastline of Barrow (8/4/09)
The coastline of Barrow (8/4/09)

Some of you have asked what the ice looks like up here. Pull out your maps and I’ll tell you about the changing ice conditions.  When I got to Barrow on 8/4/09 there was no ice visible from shore. But this changes with the winds and currents. Just one day earlier, the coastline was lined with chunks of sea ice but it had blown out to sea by the time I flew in.

As we started sailing north from Barrow into the Chukchi Sea we saw some chunks of ice but mostly dark water. Our track line (the path we follow) took us back and forth, north and south as we tested our equipment and waited to meet up with our partner ship from Canada.  As we went south, there were more patches of open water. Traveling north brought us into more ice.

What looks like dirt is really a layer of algae
What looks like dirt is really a layer of algae

Sometimes there were large patches of open water and sometimes it looked like ice all the way to the horizon. The ice that appears blue has frozen and thawed over a period of time.  When it freezes, the salt is squeezed out leaving behind fresher, bluer water.  The dark lines on the ice are patches of algae that grow at the interface between the ocean water and the sea ice.  The sea ice of the Chukchi and Beaufort Seas has retreated as far north as it will go generally by September.  We are traveling during the best open water time for this part of the world.

The Healy breaking through the ice
The Healy breaking through the ice

Now that we are traveling north, breaking a path for the CCGS Louis S. St. Laurent we are seeing less and less open water. Yesterday, (8/13/09) the view from the deck looked like a white jigsaw puzzle spread out on a black table. Each day there is more and more ice.

Today, (8/14/09) when I look out over the ice it looks like a white landscape with black lakes or rivers meandering through.  We passed 800N today and there are more ridges and large expanses of ice. On board ship there are people who are experts in sea ice. Using direct observation and satellite imagery they help the crew know what the ice conditions are going to be. In fact, there is a whole field of study concerning ice. Who knew!  If you would like to learn more, visit the website of the National Ice Center (http://natice.noaa.gov). I’ll go into this topic in more detail after I learn more.

Personal Log 

More sea ice!
More sea ice!

My goal for next this week is to learn more about how ice is classified.  I found a little book “The Observers Guide to Sea Ice” which will be a good place to start. The many ice experts on board will also be a great resource. We are hearing the sound of ice against the hull of the ship more often now and that is a pretty powerful sound. I can’t imagine what it will be like when we hit thicker ice.

The list of Inupiaq words for snow and ice is long – which makes sense.  To someone from Indiana, (like me) there might appear to be 5 or 6 different consistencies and colors of ice.  There are 76 Inupiaq words to describe ice!  Some refer to its age, composition, position to land and a host of other factors.  For example, the word for thin ice that is too dangerous to walk on is sikuaq.  Slushy ice piled up on the beach is called qaapaaq.

For my students:  Do you have any questions about Ice?