Geographic Area of Cruise: Bering Sea and Bristol Bay, Alaska
Date: July 14, 2019
Weather Data from the Bridge Latitude: 58° 36.7 N Longitude: 162° 02.5 W Wind: 9 knots SE Barometer: 1005.0 mb Visibility: 10 nautical miles Temperature: 61° F or 15.5° C Weather: Overcast with fog, no precipitation
Science and Technology Log
In the last post I talked about hydrographic surveying, the software used and the multibeam echosounder on the survey boats (called launches). The software is setup in the cabin by the hydrographer in charge. It takes a good five minutes to get an accurate read from the GPS (global positioning system) receiver. Then it takes time for the IMU (inertial measurement unit) to respond and start to read the boat’s heave, pitch, roll, yaw, and heading values.
Often, the launch drives in a circle eight in order for the positioning receivers to be “seen” by the satellites, as a stationary object is more difficult to detect than one that is moving. Setting up the day’s project using the multibeam echosounder software also takes some time but all the steps need to be done properly and to the correct specifications prior to starting the sounder. If not, the locational data will be wildly off and the depths inaccurate.
Another task that must be done from the launch before starting to transect is to test the salinity and water temperature using a CTD probe, which is called a cast. I mentioned this in a previous post. CTD stands for conductivity, temperature and depth. In the general area where the launch will survey, the CTD drops slowly to the bottom of the seafloor, collecting data that will be fed into the hydrographic program. Salinity and temperature at different depths will slightly change the rate at which sound travels in water. Again, the CTD process makes the location and depths as accurate as possible and must be done.
Usually, the chief hydrographer sets the defined area to be transected for the day and this is usually a polygon. The launch will sweep with the multibeam echosounder the outside lines and then scan at parallel set distances between the lines, either in a roughly north-south direction or a roughly east-west direction. For this particular hydrographic project, coverage of survey lines can be spaced at about 400 meters apart or greater apart depending on the depth. Recall that the nautical chart of Bristol Bay from the last post showed soundings dotting the area. Nautical charts don’t show contour lines, so solid bathymetric coverage is not always needed on these projects.
Once the technology setup is complete in the cabin, the hydrographer shares the map window with the coxswain (the person in charge of steering or navigating the boat). The hydrographer sets the points and the lines so that the coxswain knows where to direct the launch. And by direct, I mean the coxswain uses compass direction and boat speed to get from place to place for the survey. And the hydrographer in charge turns the echosounder on and off when the launch is in position or out of position.
Because the transects run parallel to each other and are equally spaced apart, the hydrographers call this technique “mowing the lawn,” (see video below) for they are essentially mowing the surface of the ocean while the multibeam echosounder is collecting soundings of the surface of the seafloor.
A day out on a launch will go from about 8:30am to about 4:30pm but sometimes an hour or so later. If the Alaskan weather is cooperating, the hydrographers want to do as much as they can while out on the launch. Once surveying is complete for the day, the hydrographer in charge has to close up and save the project. Then data get transferred to the larger workstations and shared drive on the Fairweather.
I’ve taken loads of photos and video while at sea. I have tried to post just those pictures that help explain what I’ve been trying to say in the text. I haven’t posted any video on here as the internet on the ship is very weak. These next photos are a tour of different parts of the NOAA Ship Fairweather.
The above slide show gives an idea of what the bridge is like. The ship is steered from the bridge. All the navigational instruments and weather devices, among other tools, are found on the bridge.
Did You Know?
Inertial Measurement Units (IMU) technology that is so important for accurate hydrographic survey mapping was developed by the U.S. military. IMUs were used in the development of guided missiles, unmanned aerial vehicles (and now drones), battlefield reconnaissance, and target practice.
Quote of the Day
“A ship in port is safe, but that’s not what ships are built for.” – Grace Hopper
Geographic Area of Cruise: Bering Sea and Bristol Bay, Alaska
Date: July 11, 2019
Weather Data from the Bridge Latitude: 58° 36.7 N Longitude: 162° 02.5 W Wind: 1 knot N Barometer: 1011.0 mb Visibility: 10 nautical miles Temperature: 58° F or 14° C Weather: Partly cloudy, no precipitation
What is NOAA and the Teacher at Sea program?
You may be wondering what, exactly, am I doing going “to sea” with NOAA. First off, NOAA stands for the National Oceanic and Atmospheric Administration and originates back to 1807 with Thomas Jefferson founding the U.S. Coast and Geodetic Survey (as the Survey of the Coast) with a mission to provide nautical charts to the maritime community for safe passage into American ports. Over time, the Weather Bureau was added and then the U.S. Commission of Fish and Fisheries was developed. In 1970, these three agencies were combined under one umbrella organization and named NOAA, an agency that supports accuracy and precision of physical and atmospheric sciences, protection of life and property, and stewardship of natural resources. NOAA is within the Department of Commerce.
NOAA’s Teacher at Sea (TAS) program has existed since 1990, sending over 800 teachers on NOAA research cruises. The TAS mission is “to give teachers a clearer insight into our ocean planet, a greater understanding of maritime work and studies, and to increase their level of environmental literacy by fostering an interdisciplinary research experience.” There is usually just one teacher sent per leg of a mission, that way the TAS gets full exposure to the research process and attention from the crew, scientists and staff on the ship. And it is true, everyone onboard has been friendly, helpful, welcoming, and willing to answer any question I might have, like, where is C deck? (That’s where my stateroom is located).
Science and Technology Log
Now that you understand NOAA’s mission, it should not surprise you that I am on a research cruise that is mapping a part of the seafloor that has not had detailed soundings. “Soundings” means the action or process of measuring the depth of the sea or other body of water. See the map below as that is where I am right now, in Bristol Bay. By the way, NOAA nautical charts are available for free at this NOAA site.
When I’ve told friends, family and students that I was chosen to be on a NOAA research vessel that was compiling a detailed map of the sea floor off of Alaska, it was met with great surprise. “The ocean floor hasn’t been mapped before? How could that be?” In fact, more than 80 percent of the ocean bottom has not been mapped using modern, highly precise technologies. But we do have a very coarse ocean floor – or bathymetric – map, created in the early 1950s by Marie Tharp using sounding data collected by the U.S. military and her collaborator Bruce Heezen. Tharp’s early map of the sea floor beautifully revealed the Mid-Atlantic Ridge and added another piece of evidence in support of the theories of continental drift plate tectonics. There’s a terrific Cosmos: A Spacetime Odyssey episode featuring Tharp.
Why we need a more detailed bathymetry map than the one created by Tharp and Heezen can be explained by the original mission of the early version of NOAA. Jefferson wanted to build a “…survey to be taken of the coasts of the United States…” in order to provide safe passage of ships to ports within the navigable waters of the U.S. As the Bristol Bay chart above shows, there are still coastal areas that have limited to no data. Without detailed charts, mariners cannot know where the shallower waters are (called shoals), or rock obstructions, shifted underwater sand bars, shipwrecks, or other hindrances that cause safety concerns to the movement of boats.
The hydrographic Survey Team on the NOAA Ship Fairweather use several 30 foot boats, called launches, with a multibeam echosounder attached to the hull (the bottom of the ship). The multibeam echosounder uses sonar and is a device useful for both shallow and deep water. In a nutshell, depth measurements are collected by calculating the time it takes for each of the sound pulses to travel from the echosounder through the sea water to the ocean floor and back again. The distance from the instrument to the seafloor is calculated by multiplying the travel time by the speed of sound through seawater, which is about 1,500 meters/second or 4,921 feet/second. Right before a hydrographic survey is started, the team collects information on the conductivity, temperature and depth of the sea water, as temperature and salinity will modify the density and change the travel time of the sonar pulses. The video below can explain the process further.
The software used to collect the soundings is created by the multibeam echosounder manufacturer, so the collection of millions of points on a transect is seamless. Data collection runs are taken over multiple days and several “legs” or extended periods of time when the crew are all out at the same time on the Fairweather. Following collection transects, the data are then post-processed using Caris HIPS and SIPS, which is the software that the Fairweather hydrographers use for data processing.
We’ve motored to a new location, Cape Newenham, which is the name of this mission, so we will be here for about a week. When we got underway, the ship got to really rocking and my stomach could not handle it. I had one bad night but I am now fine and ship shape!
Cape Newenham is at latitude 58°N so we are up close to the Arctic Circle (66.5°N). At this time of year, there are about 5 hours of darkness per night here in Alaska, which is really cool. Compare that what we have in New York…
Did You Know?
You probably know that Charles Darwin was the naturalist on board the HMS Beagle which set sail on December 27,1831. Over the nearly five years the Beagle was at sea, Darwin developed his ideas on natural selection and evolution of species. But what you might not know is that the captain of the Beagle, Robert FitzRoy, was an officer in the Royal Navy, a meteorologist and hydrographer. In fact, the primary mission of the Beagle was to survey the coastline of South America and, in particular, the Strait of Magellan, at the southernmost tip. Better, more accurate charts were needed by the British government, to navigate the treacherous, rough waters of the channels. In addition, FitzRoy was a protégé of Francis Beaufort (who developed the Wind Force Scale which is still used to help explain wind speed) and both worked together to create the science of weather forecasting.
Quote of the Day
“In every outthrust headland, in every curving beach, in every grain of sand there is the story of the earth.” – Rachel Carson
Geographic Area of Cruise: Aleutian Islands, Bering Sea
Date: July 8, 2019
Weather Data from the Bridge Latitude: 54° 59.104 N Longitude: 166° 28.938 W Wind: 21 knots SE Barometer: 1006.6 mb Visibility: 10 nautical miles Temperature: 53° F or 11.5° C Weather: Partly cloudy, no precipitation
Science and Technology Log
Today, we left the port at Dutch Harbor, Unalaska, Alaska and headed toward Cape Newenham. The mission for the Cape Newenham project is to gather detailed ocean depth data in order to knit together a comprehensive and highly detailed surface chart of the seafloor near Cape Newenham. I will talk about that process in my next post.
Dutch Harbor is a small town with a relatively deep port. The Ship Fairweather has a draft of 15.5 feet. “Draft” is the vertical length between the surface of the water and the bottom of the ship, which is called the hull. A ship’s draft determines the minimum depth of water a vessel can safely navigate and dock at a port. However, though the Fairweather has a 15.5 foot draft, the crew prefers a 20 foot depth of water at a port.
Dutch Harbor is part of Unalaska Island, which is one of the string of Aleutian Islands. The Aleutian Islands are part of the notorious Ring of Fire that marks the edge of the Pacific tectonic plate. As the Pacific Plate moves and grinds past some plates (like along the North American Plate at the San Andreas Fault) or pulls away from other plates (like the Antarctic and Nazca plates, creating the East Pacific Ridge) or plunges beneath other plates (like the Philippine and Indian-Australian plates, where we get deep ocean depressions called the Mariana Trench and Tonga Trench, respectively), we see active volcanism (which is the “fire”) but also lots of earthquakes. The Aleutian Islands are volcanic in origin – the island chain is a volcanic arc – and are a result of oceanic crust of the Pacific Plate being subducted under the oceanic crust of the North American plate. The deep depression at this tectonic boundary – also called a subduction zone – is called the Aleutian Trench.
Looking at a schematic drawing of the side-view, or cross section, of the Aleutian subduction zone, we can visualize what this looks like beneath the surface. The older and more dense oceanic crust of the Pacific Plate is plunging under the younger oceanic crust of the North American Plate – the more dense material sinks down or subducts – and the less dense material stays floating on top, and this process is all due to gravity. With time, as the oceanic material is drawn deeper into the subduction zone, it becomes hotter, starts to melt and then comes back up to the surface as volcanic material and a string of volcanoes forming parallel – and in this case, forming an arc – to the boundary between the Pacific Plate and the North American Plate.
I arrived at Dutch Harbor on July 6, after 14 hours and three legs of air travel. Fortunately, I made all my connections and my luggage arrived at the tiny Dutch Harbor airport. I was picked up by welcome smile for a nice person from the Ship Fairweather, got to the port and settled in to my stateroom. The “stateroom” is my sleeping quarters or room. I have it all to myself, it is very comfortable with a sink, a small bed, drawers and a closet to fit all my stuff, and there’s a TV that I haven’t yet figured out how to work.
Did You Know?
On my second day in Dutch Harbor, I went out with some new friends from the ship on a lovely hike on nearby Bunker Hill. I saw so many beautiful wildflowers along the trek and an enormous number of bald eagles. I had no idea that bald eagles would be so plentiful here, but they were everywhere. It was amazing! But the other interesting thing about this hike were the bunkers. In June 1942, Dutch Harbor was bombed by the Japanese Navy (six months after Pearl Harbor) during World War II. At the time of the raid, Alaska was a U.S. territory, and following the bombing, the bunkers of the now-known-as Bunker Hill were built to help defend not only Alaska but the west coast of mainland U.S. And here I thought Dutch Harbor was only known for Deadliest Catch!
Quote of the Day
“Even if you never have the chance to see or touch the ocean, the ocean touches you with every breath you take, every drop of water you drink, every bite you consume. Everyone, everywhere is inextricably connected to and utterly dependent upon the existence of the sea.” Sylvia Earle
Mission: Cape Newenham Hydrographic Survey Geographic Area of Cruise: Bering Sea, Alaska Date: June 25, 2019
I am so excited about my upcoming experience as a NOAA Teacher at Sea. I will be on the NOAA Ship Fairweather from July 8 to 19 and will be participating on a hydrographic research cruise, one that is mapping the sea-floor in detail; more about that soon. We will embark from and return to Dutch Harbor, Alaska, which is part of the Aleutian Islands. If you are my current or former student, or you are a friend or colleague of mine, or you are an admirer of the Teacher at Sea program, I hope you will follow along on this ocean adventure as I post about my experiences while at sea.
A little about me
I am originally from California. I went to the beach often to body surf and splash around, maybe sunbathe (I don’t do THAT anymore). It was in California where I got interested in geology. I was pretty young when I experienced the 1971 San Fernando 6.5M earthquake and after that, earthquakes were a regular occurrence for me. When I moved to Hayward, California, in early 1989 to complete my bachelor’s degree in geology at California State University East Bay, I was living off-campus and had the “pleasure” of rocking and rolling through one of the longest earthquakes I every felt when the 6.9M Loma Prieta earthquake hit. I moved on from there to the desert of Las Vegas, Nevada, to earn my Master’s in Structural Geology at the University of Nevada, Las Vegas. I didn’t feel any earthquakes in Nevada, but I did do my research on an active fault in southwestern Utah. I like to think of myself as a “boots-on-the-ground” kind of scientist-educator.
My work and life experiences are such that for five years after grad school, I was a staff geologist at a large environmental consulting company. I loved that job and it took me all around the U.S. One of the assignments I had was to manage a mapping project involving data from New York and New Jersey harbor area. From that experience I became interested in digital mapping (known as Geographic Information Systems or GIS) and switched careers. I went to work at a small liberal arts college as the GIS support person within the instructional technology group. In addition to helping teach professors and college students how to work with the GIS software, I helped teach about use of social media in teaching, use a mobile devices for data collection, integrating alternative assessments like using of audio and video, and I maintained two computer labs. While I was involved in those two different careers, I gained some adjunct teaching experiences at several different colleges and grad schools, teaching geology, environmental science and GIS.
Another professional experience that I’ve had that I am most proud of is I was a Fulbright Scholar in 2009-2010 to Barbados. My family and I lived in Barbados for a year while I was worked with the University of the West Indies, Centre for Resource Management and Environmental Studies (CERMES) I taught GIS to graduate students, I worked with some of the students on research projects, I traveled to Belize as a field assistant on a field studies trip with faculty members and CERMES students, and I had the privilege of working on a marine-based, community-driven mapping research project with a then PhD student (who has since earned her degree). My part of the project was to take the spatial data, organize it and create a user-friendly Google Earth KML file. She and I got to travel around St Vincent and the Grenadines and Grenada, teaching community members about the work, the available data, and how to access the Google Earth project file.
In 2015, I re-tooled yet again and was accepted into a challenging yet rewarding education program at the American Museum of Natural History in New York City. In 15 months, I learned how to teach with artifacts, took graduate courses in all manner or earth and space subjects, of course, had classes in pedagogical approaches, had two in-residence teaching experiences at area schools, all the while in the amazing AMNH, home of Night at the Museum.
Now as a public high school educator, teaching Earth Science to 9-12 graders in the Bronx, I have a strong foundation in the solid earth topics like plate tectonics, rocks and minerals, and geologic time. But Regents Earth Science class in New York also involves oceanography, meteorology, climate science and astronomy.
What compelled me to apply for the NOAA Teacher at Sea program is what motivates me throughout my other life decisions: I wanted to push against my boundaries and my limitations. I have always had a healthy respect for the sea, which was mixed in with a little fear. I saw the movie Jaws when I was young and impressionable, so I never really wanted to venture too far into the water beyond the waves. I didn’t even want to swim in lakes for fear of what might be traversing through the murky unknown. As I’ve aged, I’ve certainly grown less fearful of the water. I’ve traveled on sailboats and catamarans, I’ve snorkeled in the Caribbean, I’ve jumped into waters with nurse sharks and stingrays! But as a teacher who feels like she’s missing some key knowledge of her curriculum – oceanography – I want to challenge myself to learn-while-doing as I have the privilege of being selected to be a Teacher at Sea. I cannot wait!