All of the science party arrived in Nome and gathered for a science briefing before departure. In the evening there was a public presentation by Jackie Grebmeier the missions Co-Chief Scientist and Primary Investigator of the Arctic Distributed Biological Observatory – Northern Chukchi Integrated Study (DBO-NCIS). Jackie presented on what researchers have found. In brief, there is a shift northwards of the bottom dwelling Arctic ecosystems in the Bering Sea. This is due to the lack of winter ice in the southern Bering Sea causing a lack of a deep-sea cold pool of water during the rest of the year. This colder water is needed for some bottom dwelling organisms such as clams. Those clams are the favorite food choice of the Spectacled Eider Duck. When the bottom of the food chain moves north the higher in the food chain organisms such as the Spectacled Eider Duck need to adapt to a different food source or in this case move with north with it. The reason for the lacking cold pool of seawater is the lack ice being created at the surface during the winter, this process creates cold saltier water. Colder water that is also higher in salinity sinks and settles to the bottom of the ocean. So essentially the effects of less southern sea ice are from the bottom of the ocean to the top of the ocean. Grebmeier will be leading the DBO-NCS science team during this expedition so look for a future blogs focused on this research.
August 7th Evening:
We are currently anchored off the Nome Alaska Harbor and have only been on the ship for a few hours. Scientists are preparing their instruments for deployment. These instruments will measure a wide range of non-living and living members of the ecosystem. These scientific measurements will be taken from the sea floor into the atmosphere, the measurements will use a wide range of equipment. Stay tuned to future blogs with focus on different research groups, their data, specialized equipment, and their findings. We are off!
There is no place like Nome, Where the Land Meets the Sea
We are departing from Nome, Alaska. Here are some pictures around the city of Nome. Roadways to the rest of Alaska and beyond do not connect Nome. You must get here by boat or plane.
The Chum salmon were running in the Nome River, they leave the ocean and go up the river to spawn.
I found someone who traveled farther to get here than me: Arctic Terns who travel from the Antarctic to Arctic every year. In this picture, an Arctic Tern is seen with this year’s offspring. The juvenile here can now fly and will stay with its parent for the first 2 to 3 months.
This is the same variety of seagull that you see in New England, but in Alaska, this one was not so nice. As I was walking on busy road way, this gull caught me off guard and dive-bombed me, almost knocking me into incoming traffic. After several more passes, the gull decided I was not a threat to its offspring. This nest was over 200ft away. Many seabirds use the coast of Alaska to breed and raise the next generation. The common seagull, or Glaucous Gull, and Arctic Tern are only just two.
Weather Data from the Bridge
Latitude: 66° 24.440′ N
Longitude: 163° 22.281′ W
Wind: 17 knots SW, gusts up to 38 knots
Barometer: 758.31 mmHg
Visibility: 5 nautical miles
Temperature: 12.2° C
Sea Surface 9.6° C
Weather: Overcast, no precipitation
Science and Technology Log
NOAA Ship Fairweather has a variety of assignments in different parts of the west coast each year, mostly in Alaska. They also work with many different organizations. In April of 2018, the US Geological Survey, or USGS, hired the ship to complete the last part of the survey of a fault line, the Queen Charlotte Fault, which lies west of Prince of Wales Island, Alaska. This was a joint venture between the US and Canada because it is the source of frequent and sometimes hazardous earthquakes. The Queen Charlotte Fault lies between the North American Plate and the Pacific Plate. The North American Plate is made of continental crust, and the Pacific Plate is made of oceanic crust. The two plates slide past one another, so the plate boundary is known as a transform, or strike slip, fault.
The image to the right came from the USGS. Notice the two black arrows showing the directions of the North American and Pacific plates. Strike slip faults, such as this one, have the potential to produce damaging earthquakes. The San Andreas Fault in California is another example of a strike slip fault. The Queen Charlotte Fault moves relatively fast, with an average rate of 50 mm/year as shown in the photo. The USGS explains the Queen Charlotte fault beautifully in this article.
The image below was created after hydrographers on NOAA Ship Fairweather processed the data from their survey in April. The colors show relative depth across the fault, with red being the shoalest areas and blue being the deepest areas. In the top right section, you can see Noyes Canyon. There are many finger-shaped projections, which are result from sediment runoff. Notice that the color scheme in this area does not have much orange or yellow; it basically goes from red to green. If you were to look at this map in 3-D, you would see in those areas that the sea floor dramatically drops hundreds of meters in a very short distance.
It is also worth noting what can be found in the remainder of this image. When NOAA finishes their survey, two different products are formed. The first is the colored map, which you see to the far left of the image. This is useful for anyone interested in the scientific components of the area. Mariners need the information as well, but a colored schematic is less useful for marine navigation, so nautical charts are produced (or updated) for their use. A nautical chart looks just like the remainder of this image. Small numbers scattered all over the white part of the map (ie – the water) show the depth in that area. The depth can be given in fathoms, meters, or feet, so it is important to find the map’s key. The purpose of the charts is to communicate to mariners the most navigable areas and the places or obstacles that should be avoided. The nautical charts usually have contour lines as well, which give a better picture of the slope of the sea floor and group areas of similar depth together.
The photo above is a closer view of the Queen Charlotte Fault. Can you see the fault? If you cannot see it, look at the line that begins in the bottom center of the photo and reaches up and to the left. Do you see it now? On the left side of the fault lies the Pacific Plate, and on the right side lies the North American Plate. If you look even closer, you might find evidence of the plates sliding past each other. The areas that resemble rivers are actually places where sediment runoff imprinted the sea floor. If you observe closely, you can see that some of these runoff areas are shifted at the location of the fault. Scientists can measure the distance between each segment to determine that average rate of movement at this fault line.
I also wanted to briefly mention another small side project we took on during this leg. A tide buoy was installed near Cape Lisburne, which is north of Point Hope. The buoys are equipped with technology to read and communicate the tidal wave heights. This helps hydrographers accurately determine the distance from the sea surface to the sea floor. The buoy will remain at its station until the end of the survey season, at which time it will be returned to the ship.
The Fairweather team works together to launch a tide buoy in the Arctic Ocean
The Fairweather team works together to launch a tide buoy in the Arctic Ocean
The tide buoy was successfully released and will remain in the Arctic Ocean until late summer or early fall.
Tide Buoy near Cape Lisburne, AK
Northwest Alaska may not be a breathtaking as Southeast Alaska, but it has sure been an interesting trip! It amazes me that small communities of people inhabit towns such as Nome, Point Hope, and Barrow (which is about as far north as one can travel in Alaska) and endure bone-chilling winter temperatures, overpriced groceries, and little to no ground transportation to other cities. Groceries and restaurant meals are expensive because of the efforts that take place to transport the food. During my first day in Nome, I went to a restaurant called the Polar Cafe and paid $16 for an omelette! Although the omelette was delicious, I will not be eating another during my last day in Nome on Friday. It is simply too expensive to justify paying that much money. I also ventured to the local grocery store in hopes of buying some Ginger Ale for the trip. Consuming ginger in almost any form can help soothe stomach aches and relieve seasickness. Unfortunately ginger ale was only available in a 12-pack that happened to be on sale for $11.99. I decided to leave it on the shelf. Luckily the ship store has ginger ale available for purchase! The ship store is also a great place to go when your sweet tooth is calling!
Did You Know? The Queen Charlotte fault was the source of Canada’s largest recorded earthquake! The earthquake occurred in 1949 and had a magnitude of 8.1!
Question of the Day As mentioned above, northern Alaska reaches temperatures colder than most people can even imagine! Nome’s record low temperature occurred on January 27, 1989. Without using the internet, how cold do you think Nome got on that day?
Answer to Last Question of the Day:
How does a personal flotation device (PFD) keep a person from sinking?
When something is less dense than water it floats, and when it is more dense than water it sinks. Something with the same density as water will sit at the surface so that it lies about equal to the water line (picture yourself laying flat on the surface of a lake). Your body is over 50% water, so the density of your body is very close to the density of water and you naturally “half float”. A PFD, on the other hand, is made up of materials which have a lower density than water and they always float completely above water. When you wear a PFD, your body’s total density is a combination of your density and the PFD’s density. Therefore, the total density becomes less than the density of water, and you float!
Sources: Danny, et al. (2016). Investigating the Offshore Queen Charlotte-Fairweather Fault System in Southeastern Alaska and its Potential to Produce Earthquakes, Tsunamis, and Submarine Landslides. USGS Soundwaves Monthly Newsletter. https://soundwaves.usgs.gov/2016/01/.
Geographic Area of Cruise: Point Hope, Alaska and Vicinity
Date: July 10, 2018 at 5:30pm
Weather Data from the Bridge Latitude: 64° 29.691′ N
Longitude: 165° 26.276′ W
Wind: 5 knots SW, gusts up to 12 knots
Barometer: 749.31 mmHg
Visibility: 10+ nautical miles
Temperature: 16.0° C
Sea Surface Temperature: 11.9° C
Weather: Cloudy, no precipitation
Science and Technology Log
I arrived in Nome on Saturday, July 7th around 7:30pm. The weather was a beautiful 65° F with just a few clouds in the sky! By the time I settled in my stateroom (bedroom) and unpacked my belongings, it was raining! According to the Western Regional Climate Center (WRCC), Nome receives and average of 16″ of rainfall each year and 60″ of snow. Despite this fairly low rainfall total, precipitation is a frequent
occurrence in Nome. Usually, the precipitation falls as more of a light drizzle in the summer, so the accumulation over the course of a year is very small.
I am here in Nome to join NOAA Ship Fairweather on a Hydrographic Survey of the vicinity of Point Hope, Alaska. Nome is the northernmost city in Alaska with a deep enough draft dock and facilities (such as sewage disposal and fresh water) for a ship. Therefore, we will start and end our trip in Nome. The ship has been experiencing some technical difficulties, so we were not able to go underway on our scheduled day of July 9. Over the weekend, engineers discovered a leak in the exhaust from one of the ship’s engines. Left untreated, black smoke could escape into the ship and personnel could be exposed to the unhealthy fumes. As of today, the exhaust pipe has been fixed, but there are a few parts that need to be shipped to Nome to finish the job. Hopefully NOAA Ship Fairweather will be underway later this week.
Once we are underway, the trip to Point Hope will take approximately 22 hours. That means we must reserve a full day on each end of the leg (another name for the trip) for travel. In order to maximize our limited time near Point Hope, NOAA Ship Fairweather will deploy up to four 28′ boats to work at the same time. There are also enough personnel onboard to allow data to be collected on the small boats for up to 24 hours per day. Two of the four 28′ boats are shown below.
So what are these boats all doing anyways? As previously mentioned, NOAA Ship Fairweather and its small boats are designed for hydrographic research. “Hydro” is a prefix meaning “water”, and “graph” is a root word meaning “to write”. The boats will map the sea floor (i.e. – “write” about what is under the water) and any of its contents with sonar devices. Sonar is an acronym that stands for SOund Navigation And Ranging. The main sonar device used on this ship is a multibeam echosounder (MBES for short), which can be found on the underside of the ship as seen below. Sound waves are emitted from the front of the device, known as the transmitter. The sound waves travel through the water column, bounce off the sea floor, and then get picked up by a receiver adjacent to the transmitter.
There is a lot of math involved both before and after sound wave data is collected! The photo below is a CTD instrument, which stands for conductivity, temperature, and depth. Conductivity is a measure of how well an object conducts electricity. This instrument is lowered through the water column, collecting data on all three parameters listed above. The speed of sound varies based on conductivity and temperature, so the sonar data can be adjusted based on the results. For each individual data point collected along the sea floor, the actual speed of sound is multiplied by half of the time it took the sound wave to travel from transmitter to receiver. Using the equation distance = rate x time, one can find the distance (i.e. – depth) of each point along the sea floor. Put a bunch of those results together, and you begin to see a map!
Sea floor maps use color to show different depths. The most shallow areas are colored with red, while the deepest areas are colored with blue. The remaining colors of the rainbow form a spectrum that allows us to see slopes. Today, we took a small boat out and surveyed the harbor where NOAA Ship Fairweather is docked. The harbor was very shallow, so every large rock in the harbor showed up as red on the map. The deeper areas showed up as blue. Hence my blog title! In my next blog, I will include pictures of maps that have recently been completed! Stay tuned!
Living on a ship that is docked in a tiny town with little to no cell phone service is fairly challenging. However, everyone on the ship finds creative solutions to keep themselves and others entertained. It is not uncommon for groups to form in the conference room to watch a movie on the big projector screen or to host a game night. There is also a fitness room onboard with plenty of exercise options! The Bering Sea and a long beach are a short, five minute walk from the ship. We had a campfire with marshmallows the first night that everyone returned to the ship from their time off. One person in our group found a whale bone on the beach! See the picture below. I spent some time walking the water line looking for sea glass. I actually found a few pieces, in
addition to a couple of rocks I thought were quite pretty! Sea glass is made from containers, bottles, and other glass objects that end up in the ocean. Over time, these objects break into smaller pieces, and the sandy and/or rocky sea floor erodes them. By the time they reach the beach, the pieces of glass have smooth edges and a translucent color. They are fun to collect as they come in many different colors, shapes, and sizes!
Did You Know? Ocean water has a high conductivity, or ability to conduct electricity, because of all of the dissolved salts in sea water. The ions that form from dissolved salts cause ocean water to be about 1,000,000 times more conductive than fresh water!
Question of the Day If a CTD determined that the speed of sound in an area was 1,504 m/s and the time it took for the sound wave to travel from the ship’s transmitter to receiver was 0.08 seconds, how deep was the water in that specific area? Make sure to use proper units, and remember that the total time is two ways and not just one way! (Answer in the next blog post)
Date: Wednesday, August 30, 2017 Location: Port Clarence: 65o14.034N 166o43.072W
Weather on the bridge:
30+ knot winds, 42o F, 4ft seas, heavy stratocumulus clouds (9/10 coverage)
Science & Technology Log
Over the past two days I have been introduced to tremendous amounts of the science of hydrography. In this blog post I will focus on the hardware used and the process of surveying. There are two types of sonar that are being employed. The first is side scan sonar and the second is multibeam sonar.
Side scan is shorter range and performs better in shallower water. Side scan is used in conjunction with multibeam, however, as side scan does not give true depth values. The function of side scan is to show features evident on the ocean floor. For this reason, multibeam is run in conjunction with side scan in order to keep an accurate record of depths.
Multibeam shows an exact depth. Due to the fact that it is an angular spreading band from the center of the underside of the launch, at shallow depths it will only show a very narrow strip of ocean floor.
Stop and imagine…a lit flashlight shining on a wall from only a few centimeters away. What happens to the image on the wall as you pull the flashlight back? The area of coverage of the image will become larger. The concept is similar for the multibeam in shallow versus deeper water.
Using multibeam in shallow water then would create a need for more passes closer together in order to cover an area. There are instances where using this technology even in shallow water would make sense, but for a full coverage survey, this would not be the case.
The third piece of hardware used for the standard small boat launch hydrographic surveys is the CTD device. The CTD will measure conductivity of the water and also give both a temperature and density profile. The CTD is deployed multiple times during a survey as a tool to calibrate the data that is coming in via the sonar. Conductivity of the water gives an estimate of the total dissolved solids in the water. This information, along with the temperature and density will give an estimate of sound speed through the water column.
Stop and try this one for better understanding… knock on a door normally with your head roughly arm’s distance from the point where you are knocking. Now repeat the process of knocking, but with your ear pressed against the door approximately an arm’s length away from the knock. What is different? You should have noticed that a more precise (and typically louder) sound reached your ear. If you pay close attention, you will also notice that the sound reaches your ear more quickly. This is roughly analogous to how changes in the water column will affect sound speed.
The final piece of equipment used regularly for surveys is a HorCon (horizontal control) station. This is a land-based station that will help to define accurate position in the water. It allows for greater precision with global positioning data. The signals of satellites responsible for global position are affected daily by changing atmospheric conditions. Moreover, the precise positions of the satellites themselves are actually not well known in advance. This may result in a GPS location moving a few centimeters in one direction or another. While this is not going to heavily impact your ability to find a Starbucks in a strip mall, it can have a definite impact on the accuracy of charts for navigation. The HorCon station always remains in the same place on land, and can therefore be used to calibrate the measurements being read in the survey waters nearby and that information can be used along with corrected satellite positions since it is coming after the fact.
Today we worked in Port Clarence, Alaska, both outside and inside of Grantley Harbor. Most of the depths being surveyed are in the 4-6 meter range. The particular area being surveyed had been previously surveyed in the 1950s by the US Coast and Geodetic Survey, likely using a single beam sonar system. The current survey is intended to note changes that have occurred since that prior survey and to accurately update all of the charts. The area of western Alaska is expected to increase in boat traffic over the coming years due to the opening of the Northwest Passage from the Pacific to the Atlantic via the Arctic. This route is significantly shorter for most shipping traffic than the route through the Panama Canal. Because of this expected increase in traffic, there is a need to identify areas for sheltering during heavy seas. Port Clarence is a natural inlet that offers some protection and holds potential for this purpose.
The process of surveying:
Two launches were deployed. I was on launch 2808, the second described here. The first was equipped with only multibeam sonar and the second had both multibeam and side scan. The plans for the two launches were different. The launch with only multibeam was working in an area of Grantley Harbor and covering an area that had previously been mapped to insure that the values were acceptably accurate. This focus existed primarily because of extra time available up in this area. The launch running the side scan was completing some unfinished work in Port Clarence and then did further work inside of Grantley Harbor. These areas, or “sheets” are described below. As a side note, small boat deployment is a fascinating and involved activity that I will discuss in a later blog.
Survey areas are broken up into sections known as “sheets” – each sheet has a manager. This person will be from either the NOAA Corps or a civilian member of the scientific survey team. The sheet manager will be responsible for setting up the plan for survey and doing all of the final checks after data has been gathered, cleaned and examined to determine if there are areas that should be rechecked or run again before it is completed and undergoes final processing.
A sheet manager will need to consider several questions prior to setting up the initial parameters for the survey. What is the depth being surveyed? What type of bottom is it? What type of coverage is needed? All of these factors will come into play when determining how the lines will be run – how long, how far apart, which sonar type, etc.
Once the plan is determined, it will be the job of the Operations Officer, LT Damian Manda, to parse out the duties and create a daily work plan to cover all of the areas. Each day, multiple launches will be sent out to gather data as described above. As the fieldwork finishes for the day, data will be transferred to a drive and then brought into the ship’s mapping room where night processers will begin the lengthy work of checking and cleaning the data so that it can all be ready for the final processing step prior to being sent to the client.
How good are those data?
There are several checks built into the data collection process. First, the survey team members on the launches are watching in real time. With three screens to work from, they are able to see what the sonars are seeing and can also set certain limits for the data that will alarm when something appears to be contrary to what’s expected. Night processors look for anomalies in the data like sudden inexplicable drops in depth in an otherwise flat surface or an extremely “noisy” area with little good data. Any area with a former survey will also be compared to the previous values with large differences signaling possible issues. Many trained eyes look at the data before it is accepted for charting and there will commonly be at least one return to an area to check and recheck prior to completion. One area in the current survey has continued to show odd results, so trained NOAA divers will dive the area to find out what is really going on.
So far this has been an amazing experience. I fully enjoy being among the crew of the Fairweather and living on the ship. It’s hard to say what my favorite part has been so far because I have honestly enjoyed all of it! Since we didn’t get underway until Monday, I had the opportunity on Sunday to roam around Nome with a couple of the other folks that are just here for two weeks, LT Joe Phillips and LCDR Ryan Toliver. I learned a lot more about both the NOAA Corps and the Public Health Service of which they are respectively a part. (These are two of the seven uniformed services – can you name the other five?) NOAA Corps officers are in command on all of the active NOAA commissioned ships and aircraft and you will learn a lot more about them in future posts. The PHS is an organization made up primarily of medical professionals. These folks serve in various medical and medical research positions around the nation. There are many who will work for the National Institutes of Health in research, or the Bureau of Prisons or commissioned vessels like Fairweather as practitioners. Unlike NOAA Corps, PHS is not on a billet cycle where every two to three years you will be moved to a new position in a different office or location. Similar to all of the other uniformed services, though, promotion through the ranks is both encouraged and desired.
We also saw the marker for the end of the Iditarod race. I was able to see the historic beginning in Seward, Alaska back in 2010, so seeing the end in Nome was an unexpected treat. Nome also has Cold War-era missile early warning system arrays at the top of a mountain nearby. We had a chance to hike around them and see some of the interesting geologic features of the area. There’s so much more to talk about, but I think I’ll stop here and save shipboard life for my next post.
Did You Know…
… that the Iditarod has its historic beginnings with the Public Health Service? There were many children in interior and western Alaska dying of diphtheria in the early 1920s. When it reached epidemic proportions, the only doctor in Nome reached out to the PHS in the lower 48 to ask for help. Vials of serum were found and sent north to Seward, but then because of heavy ice and storming, dog sled teams were used to get the vials to the interior towns and to Nome. The original race along the Iditarod Trail was run as a memorial to the “Serum Run” and eventually evolved into the highly competitive race it is today.