National Weather Service – NOAA Teacher at Sea Blog

July 18, 2023July 18, 2023

Jenny Gapp: Reporting to 551.46 (Oceanography), July 19, 2023

NOAA Teacher at Sea

Jenny Gapp (she/her)

Aboard NOAA Ship Bell M. Shimada

July 23 – August 5, 2023

Mission: Pacific hake (Merluccius productus) Survey (Leg 3 of 4)
Geographic Area of Cruise: Pacific Ocean off the coast of Newport, Oregon
Date: July 19, 2023 (pre-cruise)

Weather Data from Newport, Oregon
NOAA Weather Service forecast for Wednesday, July 19th as of 7/17/23 6:35pm:
Mostly sunny, then sunny and breezy, with a high of 61 degrees. Wednesday night’s low around 55 degrees.

“Weather” is what it’s doing today. “Climate” is what it did today in 1942. Climate equates to the prevailing weather trends for a particular region. Having been born and raised in Oregon I know that you always dress in layers when going to the Oregon Coast. I know that sunburn is possible in March (anytime really) and balmy 60-degree weather is possible in February. Historically, the average temperature for the month of July in Lincoln County has remained between 60 and 63 degrees with a slight trend upward. I imagine it is a bit chillier out on the Pacific. I have packed accordingly!

A week from departure (July 16th) I was looking south from the cliffs on Cape Lookout near Tillamook, Oregon. The breeze was visible in shimmering white flashes across the surface of the ocean even as the tidal swells plowed steadily into shore beneath the gusts. The infamous summer fog shrouded much of the cape’s seaward view due to temperature and pressure differences between the coast and inland.

view of Cape Lookout from the cliffs. Beyond dirt cliffside and conifer trees, we can see the water is a vivid blue-teal color. A mountain range marks the far side of the cape. The sky is blue, but fog rises off the water.

As air heats up it ascends (rises), leading to low pressure at the earth’s surface. As air cools down it descends (sinks), leading to high pressure at the surface. Hot summer air rises inland and creates low pressure. Since the temperature of the ocean is much colder, high atmospheric pressure is formed. Higher-pressure air tends to move into lower-pressure regions, so the moist marine layer (caused by evaporation) gets pulled off the top layer of the water and moves inland. All that moisture creates low-flying clouds, known as “fog” when it touches the ground. Marine fog moves eastward (inland) and usually clings to the shoreline. Sometimes it moves further depending on the topography of the coast range. Summer winds on the Oregon Coast are caused by temperature-driven atmospheric pressure disturbances where the two pressure systems collide.

a diagram in three panels. each panel includes an illustration, in cross section, of a hilly coastline rising above the ocean. icons shaped like thermometers show temperature readings right near the shoreline, at the seaward base of the mountain, and at the far side of the mountain. Top panel: Early Morning, cloudy, temps of 60, 65, 75 degrees. Middle: Late morning, fog, temps of 60, 70, and 85 degrees. Bottom: Afternoon, sea breeze, temps of 70, 85, and 105 degrees. — https://www.seasonsinthesea.com/may/phys.shtml

diagram depicting cold air as straight black arrows flowing to the right, wind as a curvey blue triangle, and warm air as wavy orange lines rising diagonally — Why does wind blow? NOAA SciJinks | https://scijinks.gov/wind/

Listening to the weather forecast was something of a ritual in my childhood home. Mom would tune in to WKL96 at 162.475 and we’d dutifully hush up when the familiar “ding!” occurred to signal the top of the broadcast. To this day she still writes down the short-term forecast and puts it on the fridge. (Mom is an old-fashioned gal and doesn’t use the internet.) Find your local station here.

I got to tour my local National Weather Service office –home of the “ding!”– in Portland, Oregon during a DataStreme Climate class I took in 2016. Sponsored by the American Meteorological Society, I also took their DataStreme Oceans course. I highly recommend these classes to educators.

I’m a bit of a NOAA snob when it comes to the forecast. My old Subaru had a channel entirely devoted to NOAA Weather Radio. My new (used) one doesn’t, and I miss it! Friends and family look at a variety of weather apps, but I will always check their predictions against what NOAA says. When you visit National Park Visitor Centers around the country it’s usually the short-term NOAA forecast that is posted on visitor information boards. It is possible to access NOAA Weather from your phone. Go to the following website to learn how to add a bookmark to your phone’s home screen.

the cover of the book A Crack in the Sea by H. M. Bouwman.

Librarian at Sea

“Traditionally, a few people from Raftworld would decide to stay on the island; and a few from the Islands would elect to join Raftworld. These were volunteers, and they were celebrated for their choosing, for some people were simply happier living on land, and others happier at sea.”
~H. M. Bouwman, A Crack in the Sea
(G.P. Putnam, 2017)

A Crack in the Sea is a middle-grade novel that blends fantasy with historical fiction, including characters who flee a slave ship, and those fleeing post-war Vietnam. One character also has a special skill: talking to fish. My special skill is talking to children about books…but I do much more than that.

Introduction & Background

I have reported to 551.46 many times over my 18 years as a school librarian, but this will be my first reporting to its physical manifestation. Despite growing up near the coast I have never been out on the open ocean in a boat. I have visited the nonfiction shelves (organized by Melvil Dewey) countless times. You’ll find oceanography topics at 551.46. You’ll find my school, Peninsula Elementary, on an earthen finger of Portland, Oregon bordered by the Willamette River to the west and the mighty Columbia River to the north. Peninsula has been my anchor as an educator for the past 12 years. I call myself a “teacher librarian” in order to emphasize that my priority is to design and deliver lessons to students on top of managing a small library. My profession has state and national standards that cover information literacy, reading engagement, and social responsibility. One of the things I love most about being a school librarian is the academic freedom that I have. I can teach my standards by using the story of the haenyo mermaids of Korea, by analyzing infographics of the water cycle, and by playing truth or lie with shark facts. Cross-curricular approaches to learning are what get me excited about teaching. Science in particular is a subject I have long gravitated towards.

My career in a, er, clamshell: As an undergraduate with a BA in Comparative Literature I said, what next? I promptly got a seasonal job as a Ranger Aide for Silver Falls State Park. What next? I applied to permanent ranger jobs…and my old school district (where I graduated high school) was looking for a school librarian. My alma mater hired me with zero experience on a restricted transitional license–which means I promised to go back to school and get certified. So, I got my teaching license, then a Master’s in Library Science–two distinct programs. While in graduate school I began branding myself as a “Ranger Librarian.” While working for the same junior high I once attended, I had the odd experience of working with colleagues who were formerly my teachers. A beloved high school social studies teacher still worked next door on our shared campus. He encouraged me to seek out opportunities for educators that provided residencies, travel opportunities, and hands-on learning. So, when I saw a brochure in the staff lounge for an Outward Bound course designed just for teachers I applied. What next? I applied for a Cultural Resources Internship at Grand Teton National Park where, among other things, I created an information package for prospective researchers to help them navigate the application process and eliminate research redundancy. I learned, for example, there is such a thing as collecting too many voles. I applied for a “Teacher Ranger Teacher” position at Grand Canyon National Park. I applied to be a seasonal ranger again, this time in the Columbia River Gorge. I applied for a Comparative Mountain Geography Institute with the Center for Geography Education in Oregon. I did all those things in the margins of my life as a teacher librarian. What next? I applied to be a NOAA Teacher at Sea!

As the others in NOAA TAS Class of 2022 and 2023 will confirm, I then played the pandemic waiting game while the world figured out how to function with COVID. TAS candidates have to pass a medical clearance within a year of sailing so I even gave blood not once, but twice, while time and tide marched on. I have yet to sweat, and yet to cry, but the salt swims at the ready.

we see only Jenny's and her husband's bare feet on the sand. The beach stretches well ahead of their feet to the ocean, a dark teal green lined with whitecaps where the waves are breaking. a vessel is only just visible on the horizon. — Getting a sunburn in March 2023 near Manzanita, Oregon with my husband. You can see a fishing boat in the distance.

Science, Technology & Career Log
You can track the location of NOAA Ship Bell M. Shimada as well as other vessels here. Alternatively, you can try this tracker. Marine traffic includes all ships at sea such as tankers, military vessels, passenger ships, and fishing boats. An automatic identification system, or AIS technology, is used to follow traffic locations. The International Maritime Organization (a branch of the United Nations) launched the development of AIS as a collision avoidance tool for large vessels at sea that were not within range of tracking systems based on shore.

The IMO decided that all vessels over 300 gross tonnages on international voyages must have AIS aboard. A gross tonnage is calculated by measuring a ship’s volume. AIS allows ships to “see” each other and improves situational awareness before visual contact is possible. AIS is considered by some to be the most significant improvement to navigational safety since the development of radar. However, AIS is considered an enhancement and not a replacement for radar and other traffic services. Using a broadcast transponder system, AIS operates in the VHF (very high frequency) radio waves mobile maritime band. A complete system includes a transmitter and a receiver with data displayed on a screen (revealing the bearing and distance of nearby vessels). Originally, AIS made broadcasts from ships to land and had a capacity of 20 miles or so. Today, satellite-detected AIS allows us to “see” ships no matter how far away.

screenshot from Marine Traffic website marking the position of NOAA Ship Bell M Shimada with a tiny aqua-blue triangle just west of San Francisco. many other markers of different colors and shapes mark the positions of other vessels or buoys. — Position of NOAA Ship Bell M. Shimada not long after the departure of Leg 2. Destination: Newport, Oregon

Radio waves are one type of electromagnetic radiation–in the same family as X-rays, visible light, microwaves, infrared, and ultraviolet. Naturally occurring radio waves include lightning and objects in space including Jupiter and The Sun. It is possible to turn information like text, sound, and images into electrical signals. These signals are combined with radio waves–energy that moves–to send information across long distances. High-frequency waves have a shorter wavelength and send more wavelengths per second than low-frequency waves. In general, higher frequencies do not travel as far, which is why satellites have proven so useful to AIS. (Further reading)

physics diagram comparing high frequency waves (with short wavelengths) to low frequency waves (with long wavelengths)

Electromagnetic Spectrum: Radio Waves (BestOfScience)

Career feature

I am excited to meet all the people behind the research and ship operations. Prior to sailing, I checked out the professional mariner hiring portal facilitated by NOAA’s Office of Marine and Aviation Operations. Current fleet vacancies included able seaman, oiler, and first assistant engineer. Reading the job descriptions brought to mind two things. One is my maternal grandfather. He was a World War Two Navy Veteran who worked as a motor machinist and drove a Higgins Boat on D-Day during the invasion of Normandy. He did not die in the war, but lived to age 89 and passed away in 2012. Among the family archives are records of his completion of a diesel mechanics course. This association made me think about encouraging students to make personal connections to whatever we are learning about. After reminiscing about Grandpa, my train of thought spitballed keywords like boat, engine, ship, sailor, mechanic, and Titanic–which served as a bridge to thought number two. The fleet vacancies prompted a daydream about the next time I am helping a student interested in library books on one of these tangential ocean topics. In addition to a forthcoming lesson on NOAA careers, I should remember to mention a related career during book shopping and plant a seed. “Hey Johnny, I see you are interested in ships. Did you know that being a sailor is an actual job that you could do one day?”

My maternal grandfather, Leroy Bowers. WWII Navy Veteran.

NOAA Fisheries has its own job opening portal. Openings at the time of my website visit included a statistician, IT Specialist (systems administrators are needed everywhere!), fish biologist, physical science technician, grants management specialist, budget analyst, enforcement technician, and acquisition management specialist. Fish biologist was an obvious choice but I had to click on enforcement technician to find out more. It appears to be an entry-level position related to NOAA’s Office of Law Enforcement (see video insert).

Holy mackerel, this initial career investigation blew my mind with how many employment opportunities there are within NOAA. I think my students will be impressed with the broad scope of career choices as well.

Floating Facts

NOAA Ship Bell M. Shimada (in service since 2010) serves the entire West Coast and furthers the NOAA Fisheries mission to be “responsible for the stewardship of the nation’s ocean resources and their habitat.” The imperative of NOAA Fisheries is to maintain healthy ecosystems, safe sources of seafood, productive and sustainable fisheries, as well as the recovery and conservation of protected resources. NOAA’s parent agency is the U. S. Department of Commerce and so relates to economic growth and opportunity. Bell M. Shimada is known as a “quiet” ship, using technology to decrease its noise signature and increase scientists’ abilities to study fish without disturbing them.

Bell M. Shimada, the man, was known for his studies of Pacific tuna stocks important to the development of commercial fisheries post-World War Two. His name was chosen by a group of California high school students in a contest to name a new ship in the NOAA fleet. Born to Japanese immigrants in Seattle, Washington, he was imprisoned at Minidoka War Relocation Center in 1942 during the mass internment of Americans with Japanese ancestry. He was 20 years old at the time. He was able to leave the camp by enlisting in the U. S. Army. Shimada began as an infantryman, then an interpreter, translator, and radio traffic monitor, then compiled data on the impact of bombings in Japan. He ended up in Tokyo during its occupation and remained after the war in a civilian position where he analyzed the activities of Japanese fisheries. He returned stateside to finish a college degree that had been interrupted by internment. He went on to earn a Master’s and moved to Honolulu to work for the Fish and Wildlife Service. He worked with an influential fisheries scientist pioneering a holistic approach to fish management, blending fish biology with oceanography and meteorology. While in Honolulu he also began work on a Ph.D. The tuna research he is most well known for occurred when he was transferred to the Inter-American Tropical Tuna Commission in La Jolla, California.
His scientific pursuits were cut short in a plane crash en route to Mexico City on a return trip from a scientific cruise to Clarion Island off the west coast of Mexico. Shimada was just 36 years old. Think of this remarkable scientist next time you open a can of tuna…

front of a collector's card of NOAA Ship Bell M. Shimada, fisheries survey vessel

ttext reads: Bell M. Shimada. This ship is used to study marine life, sea birds, and ocean conditions along the U.S. West Coast. Homeport: Newport, OR. Commission date: August 25, 2010. Length: 208.6 ft. Areas of operation: Pacific ocean. Fun Fact! This ship was designed to run queitly as not to disturb fish and marine mammals during research studies. www.noaa.gov/education. www.omao.noaa.gov/learn/marine-operations/ships

Bell Shimada sits, shirtless, on the deck of a vessel surrounded by coils of rope

Hook, Line, and Thinker

As a part of my interdisciplinary approach to learning in the library, I often use philosophical questioning in order to inspire dialogue among my students. Something to think about…Is taking a creature’s life justified when it benefits the greater good? Many hake have given their bodies to science in order to not only benefit human activity but their own species as well.

Hmm, I made a Freudian slip just now. I originally wrote, “when it benefits the greater food.” I guess I’ve outed myself as a meat eater and a utilitarian when it comes to the sacrifice of creaturely bodies–within reason (remember the voles)–in the name of science.

A Bobbing Bibliography

Books I currently use in the classroom to further ocean literacy with elementary students.

Books I use with grades K-2:

Inky’s Amazing Escape: How a very smart octopus made his way home, by Sy Montgomery (Simon & Schuster, 2018)
Inky the Octopus, by Erin Guendelsberger (Sourcebooks Wonderland, 2020)
Octopuses One to Ten, by Ellen Jackson (Beach Lane Books, 2016)
Whale in a fishbowl, by Troy Howell & Richard Jones (Schwartz & Wade, 2018)
Deep in the Ocean, by Lucie Brunelliere (Abrams Appleseed, 2019)
In the Sea, by David Elliott and Holly Meade (Candlewick, 2012)
Alien Ocean Animals, by Rosie Colosi (National Geographic Kids, 2020)
Ocean! Waves for All, by Stacy McAnulty (Henry Holt and Co., 2020)

Books I use with grades 3-5:

The Brilliant Deep: Rebuilding the World’s Coral Reefs: The Story of Ken Nedimyer and the Coral Restoration Foundation, by Kate Messner (Chronicle Books, 2018)
Science Comics: Coral Reefs: Cities of the ocean, by Maris Wicks (First Second 2016)
Otis & Will Discover the Deep: The record-setting dive of the bathysphere, by Barb Rosentock (Little, Brown Books for Young Readers, 2018)
The Mess That We Made, by Michelle Lord (Flashlight Press, 2020)
The Ocean Calls: A Haenyeo Mermaid Story, by Tina Cho (Kokila, 2020)
Manfish: Jacques Cousteau, by Jennifer Berne (Chronicle Books, 2008)
Ocean Speaks: How Marie Tharp revealed the ocean’s biggest secret, by Jess Keating
Shark Lady: The True Story of How Eugenie Clark Became the Ocean’s Most Fearless Scientist (Sourcebooks Explore, 2017)
Marine Science for Kids: Exploring and Protecting Our Watery World, by Josh & Bethanie Hestermann (Chicago Review Press, 2017)

During the three years I was sailing through the rough waters of the pandemic I took a hard look at the ocean-themed books in our school library collection. Library acquisition budgets are always tight, so I wrote a Donors Choose grant to purchase about 50 new titles. Since this occurred while I taught remote classes, my thank you package was also virtual. Students did a lovely job documenting their thanks using the tools they had available to them. I believe my NOAA experience will help me further promote the content of 551.46!

collage of digital children's artwork, and photos of children holding up handdrawn artwork, saying "Thank you donors, we love our new ocean books!" The children's faces are covered for privacy.

June 25, 2013August 11, 2021

Robert Ulmer: Build Upon a Strong Foundation, June 19, 2013

NOAA Teacher At Sea

Robert Ulmer

Aboard NOAA Ship Rainier

Underway from June 15 to July 3, 2013

Current coordinates: N 56⁰35.547’, W 134⁰36.925’

(approaching Red Bluff Bay in Chatham Strait)

Mission: Hydrographic survey

Geographical area of cruise: Southeast Alaska, including Chatham Strait and Behm Canal, with a Gulf of Alaska transit westward to Kodiak

Log date: June 19, 2013

Weather conditions: 10.93⁰C, less than 0.5 km visibility in thick fog, 95.42% relative humidity, 1013.38 mb of atmospheric pressure, light variable winds (speed of less than 3 knots with a heading between 24⁰ and 35⁰)

Explorer’s Log: Survey, sample, and tide parties

Scientists are explorers, wandering the wilderness of wonder and curiosity their with eyes and minds wide open to events, ideas, and explanations that no other humans may have previously experienced. And by definition, explorers — including scientists — also are builders, as they construct novel paths of adventure along their journeys, built always upon the strong foundations of their own reliable cognitions and skill sets.

Ensign Rosemary Abbitt making a level sighting measurement

Starting from their own observations of the world around them, prior knowledge, and context, scientists inject creativity and insight to develop hypotheses about how and why things happen. Testing those ideas involves developing a plan and then gathering relevant data (pieces of information) so that they can move down the path of whittling away explanations that aren’t empirically supported by the data and adding to the collective body of knowledge, so that they and others might better fathom the likely explanations that are behind the phenomena in question.

Rainier lowering a launch vessel — NOAA Ship *Rainier* lowers launch vessel RA-5 for a survey excursion.

Because progress along the scientific path of discovery and explanation ultimately depends on the data, those data must be both accurate and precise. Often these terms are confused in regular conversation, but each word has its own definition.

Approaching the shore from the skiff — A view from the skiff of the shoreline where the benchmarks and tide gauge staff already are installed.

Accuracy is a description of the degree of closeness or proximity of measurements of a quantity to the actual value of that quantity. A soccer player who shoots on goal several times and has most of his shots reach the inside of the net is an accurate shooter. Likewise, a set of measurements of the density of a large volume of seawater is more accurate if the sample data all are near the actual density of that seawater; a measurement that is 0.4% higher than the actual density of the water is just as accurate as another measurement of the same water that is 0.4% below the actual density value.

HAST Curran McBride visually examining the condition of the tide staff — Before making more detailed data collections, Hydrographic Assistant Survey Technician (HAST) Curran first conducts a visual inspection of the previously-installed tide staff upon arriving at the shore.

Precision (also called reproducibility or repeatability), on the other hand, is the degree to which repeated measurements under unchanged conditions show the same results. If every shot attempted by the soccer player strikes the left goalpost four feet above the ground, those shots aren’t necessarily accurate – assuming that the player wants to score goals – but they are very precise. So, similarly, a set of measurements of seawater density that repeatedly is 5.3% above the actual density of the water is precise (though not particularly accurate).

HAST Curran McBride collecting data near the tide staff — HAST Curran collects data near the tide staff during the closing level run in Behm Canal.

The NOAA teams that conduct hydrographic surveys, collect seafloor samples, and gather data about tide conditions must be both accurate and precise because the culmination of their work collecting data in the field is the production of nautical charts and tide reports that will be used around the world for commerce, recreation, travel, fisheries management, environmental conservation, and countless other purposes.

Cabin of the launch vessel — Crew of the survey/sample team in the cabin of the launch vessel (and the Coxswain piloting the boat)

Hydrographic surveys of some sort have been conducted for centuries. Ancient Egyptian hieroglyphs show men aboard boats using ropes or poles to fathom the depths of the water. In 1807, President Thomas Jefferson signed a mandate establishing the Survey of the Coast. Since that time, government-based agencies (now NOAA’s Office of Coast Survey) have employed various systems of surveying depths, dangers, and seabed descriptions along the 95,000 miles of navigable U.S. coastlines, which regularly change due to attrition, deposition, glaciation, tectonic shifts, and other outside forces.

Analyzing data aboard the launch — Hydrographic Senior Survey Technician Barry Jackson and Physical Scientist Kurt Brown analyze historic and new data from multi-beam sonar aboard the launch vessel.

For most of that history, data were collected through a systematic dropping of weighted lines (called “lead lines”) from boats moving back and forth across navigable channels at points along an imaginary grid, with calibration from at least two shore points to assure location of the boat. Beyond the geometry, algebra, and other mathematics of measurement and triangulation, the work was painstakingly slow, as ropes had to be lowered, hauled, and measured at every point, and the men ashore often traveled alongside the boat by foot across difficult and dangerous terrain. However, the charts made by those early surveys were rather accurate for most purposes.

The biggest problem with the early charts, though, was that no measurements were made between the grid points, and the seafloor is not always a smooth surface. Uncharted rocks, reefs, or rises on the seabed could be disastrous if ships passed above them.

HSST Barry Jackson collecting sea floor sample — HSST Barry Jackson pulls a line hand over hand to retrieve a scooped sea floor sample from a depth of more than 45 meters in Behm Canal.

HSST Barry Jackson analyzing sea floor sample — … and then analyzes what the scoop captured: mud and gravel in this case.

Starting in the 1990s, single-beam sonar became the primary mechanism for NOAA’s surveys. Still looking straight down, single-beam sonar on large ships and on their small “launch vessels” (for areas that couldn’t be accessed safely by larger craft) provided a much more complete mapping of the seafloor than the ropes used previously. Sonar systems constantly (many times per second) ping while traveling back and forth across and along a channel, using the speed and angle of reflection of the emitted sound waves to locate and measure the depth of bottom features.

Handwritten notes about sea floor samples — Data about sea floor samples first are recorded by hand on a chart aboard the launch vessel before being uploaded to NOAA computers later.

Sound waves travel at different speeds through different materials, based on the temperature, density, and elasticity of each medium. Therefore, NOAA also deploys CTD devices through columns of surveyed waterways to measure electrical conductivity (which indicates salinity because of ionization of salts dissolved in the water, thus affecting solution density), temperature (which usually is colder at greater depths, but not necessarily, especially considering runoff from glaciers, etc.), and depth (which generally has a positive-variation relationship with water pressure, meaning more pressure – and thus, greater density – as depth below the surface increases).

CTD device about to be deployed — This CTD device measures conductivity, temperature, and depth in the water. All three affect the speed of the sound waves in water, and the speed of sound is a necessary bit of data when using sonar (which tracks reflected pings of sound) to determine the distance to the sea floor.

The most modern technology employed by NOAA in its hydrographic surveys uses multi-beam sonar to give even more complete coverage of the seafloor by sending sound waves straight downward and fanned outward in both directions as the boat travels slowly forward. Even though sonar beams sent at angles don’t reflect as much or as directly as those sent straight downward, uneven surfaces on the seabed do reflect some wave energy, thus reducing the occurrence of “holidays” (small areas not well-defined on charts, perhaps named after unpainted bits of canvas in portraits because the painter seemed to have “taken a holiday” from painting there).

Acquiring hydrographic data — FOO Mike Gonsalves and HAST Allix Slagle acquire hydrographic data with the ship’s Kongsberg EM-710 multi-beam sonar.

TAS Rob Ulmer retrieving sea floor sample in Behm Canal — Aboard the small launch vessel, everyone works. This is Teacher At Sea Rob Ulmer hauling in a sea floor sample in Behm Canal.

But that’s not all. To help sailors make decisions about navigation and anchoring – and often giving fishermen and marine biologists useful information about ecology under the waterline – NOAA also performs systematic samples of the types of materials on the sea floor at representative points in the waterways where it conducts surveys. Dropping heavy metallic scoop devices on lines* dozens of meters long through waters at various locations and then hauling them back aboard by winch or hand-over-hand to inspect the mud, sand, silt, gravel, rocks, shells, plants, or animals can be physically demanding labor but is necessary for the gathering of empirical data.

* A note about terminology from XO Holly Jablonski: Aboard the ship, lines have a job. Think of a “rope” as an unemployed line.

Additionally, Earth’s moon and sun (along with several underground factors) affect the horizontal and vertical movement of water on Earth’s surface, especially due to their gravitational pulls as Earth spins on its axis and orbits the sun and as the moon orbits Earth. Therefore, information about tides is extremely important to understanding the geography of nautical navigation, as the points below the waterline are identified on charts relative to the mean low water mark (so sailors know the least amount of clearance they might have beneath their vessels), and points above the waterline are identified relative to the mean high water mark (including notation of whether those object sometimes are fully submerged).

Evidence of tidal changes along the shoreline of Behm Canal — Can you see the evidence of tidal changes along the shoreline of Behm Canal? Color differences form strata along the rocks, and lowest leaves of the trees give further evidence of the highest reach of the water.

Ensign Damian Manda manually levels the sighting rod upon the “turtle” using a carpenter’s bubble-leveling device.

To gather accurate and precise data about tidal influences on local waters, NOAA sends tides-leveling shore parties and dive teams into difficult conditions – commonly climbing up, down, and across rock faces, traversing dense vegetation, and encountering local wildlife (including grizzly bears here in Alaska!) – to drill benchmarks into near-shore foundation rocks, install (and later remove) tidal gauges that measure changing water heights and pressures, and use sophisticated mathematics and mechanics to verify the levels of those devices.

Pondering the next measurement — Ensign Rosemary Abbitt and HST Brandy Geiger ponder the placement of equipment before the next level measurement.

Needless to say, this description is significantly less detailed than the impressively intricate work performed at every level by NOAA’s hydrographic scientists, and in the end, all of the collected data described in the paragraphs above – and more, like the velocity of the sonar-deploying vessel – must be analyzed, discussed, and interpreted by teams of scientists with broad and deep skills before the final nautical charts are published for use by the public.

Portable tools of the trade — A leveling rod is balanced on the highest point of a “turtle,” positioned carefully to be seen from multiple points.

As you choose where and how to proceed in your own journeys, remember that you can be more confident about your decision-making by using information that is both accurate and precise. And keep exploring, my friends.

View from the benchmark — This is the view from the benchmark atop a rocky outcropping (under an 80-foot evergreen) along Behm Canal while righting a measurement rod with the tide gauge leveling party.

Did You Know?

NOAA Ship Rainier in Behm Canal with launch vessels underway — NOAA Ship *Rainier* in Behm Canal with launch vessels underway

Every ship in the NOAA fleet also is a voluntary mobile weather station, and so are many other seagoing vessels around the world. For many years ships have been required to report their locations and identities on a regular basis to agencies like the U.S. Coast Guard and local or regional harbormasters. Those periodic reports were (and still are) vital for local traffic control on the waters and for helping to provide quick response to emergency situations on vessels at sea.

View aft while launch is underway — The view aft through Behm Canal from the launch vessel

Eventually, someone insightful realized that having the ships also provide weather reports from their positions along with those identity-and-location reports would make a much richer and broader network of timely data for the National Weather Service, which is another branch of the National Oceanic and Atmospheric Administration. As NWS adds the weather data from those many boats to the data gathered at land-based NWS stations and from voluntary land-based reporters of conditions, their models and forecasts become stronger.

(For more info about being a volunteer weather observer or volunteering with NOAA in some other capacity related to oceans, fisheries, or research, please visit www.volunteer.noaa.gov.)

Especially because weather conditions are the results of interactions among local phenomena, regional climate, and the global systems, building more accurate and precise forecast models depends on information from everywhere, but the result is that everyone benefits from the better forecasts, too.

Evidence of tectonic activity and rundown — Southeast Alaska is area with frequent tectonic activity, including uplift and earthquakes. Here a scar among the trees on the mountainside shows evidence of tectonic shifts, which also creates a ready path for meltwater to move downhill from the snowy mountaintop to the seawater below, taking trees and soil with it.

NOAA Ship Rainier ready for the returning skiff — NOAA Ship *Rainier* waits offshore, ready to receive the skiff returning with the tide/level shore party.