shipwreck – Page 2 – NOAA Teacher at Sea Blog

May 9, 2016August 21, 2021

Nichia Huxtable: Time to Make a Map, May 8, 2016

NOAA Teacher at Sea

Nichia Huxtable

Aboard NOAA Ship Bell M. Shimada

April 28 – May 9, 2016

Mission: Mapping CINMS
Geographical area of cruise: Channel Islands, California
Date: May 8, 2016
Weather Data from the Bridge:

Science and Technology Log

Seafloor in CINMS — Seafloor in the CINMS

In previous posts, I’ve discussed the ME70 multibeam sonar on board Shimada. You’d think that I’ve told you all there is to know about the wondrous data this piece of equipment provides, but oh, no, dear readers, I’ve merely scraped the surface of that proverbial iceberg. In this post, I will explain how the raw data from the ME70 is used to create important seafloor maps. Heck, I’ll even throw in a shipwreck! Everyone loves shipwrecks.

Nichia Huxtable, Diana Watters, ME70, and EK60; aboard Shimada

Back to the multibeam. As you may remember, the ME70 uses many beams of sonar to capture a 60 degree image of the water column. It collects A LOT of data, one survey line at a time. Lots of data are good, right? Well, if you want to map the bottom of the ocean, you don’t need ALL the data collected by the ME70, you just need some of it. Take, for example, fish. You don’t want big balls of fish obscuring your view of the seafloor, you just want the seafloor! Leave the schools of fish for Fabio.

Kayla Johnson aboard NOAA Ship Bell M. Shimada — Mapping maven Kayla Johnson

The person you need to make your seafloor map is Kayla Johnson. First, she sends the raw data to a program called MatLab. This nifty software separates the bottom data from all the other stuff in the water column and packages it in something called a .gsf file. Next, this .gsf file goes to this huge processing program called CARIS HIPS, where it is converted into an something called HDCS data.

You’d think that all you’d need to make an accurate seafloor map would be data from the multibeam, but it is actually much more complicated than that (of course you knew that! just look at how long this blog post is). Think about it: while you’re running your survey lines and collecting data, the ocean and, therefore, the ship are MOVING. The ship is heaving, rolling, and pitching, it’s travelling in different directions depending on the survey line, the tides are coming in and out, the temperature and salinity of the water varies, etc. etc. All of these variables affect the data collected by the ME70 and, hence, must be accounted for in the CARIS software. Remember how I said it was HUGE? This is why.

Cross-section of the topography found in the CINMS

Everyone still with me? Ok, let’s continue processing this data so that Kayla can make our beautiful map. Next up, she’s going to have to load data into CARIS from the POS. POSMV (POSition of Marine Vehicles) is a software interface used on the ship that collects real-time data on where we are in relation to the water (heave, pitch, and roll). She’s also going to load into CARIS the local tide information, since the ship will be closer to the seafloor at low tide than at high. Not including tidal change is a good way to get a messed-up map! Once the POSMV and tide files are loaded into CARIS, they are applied to the survey line.

Next, Kayla has to compute the TPU (Total Propagated Uncertainty). I could spend the next four paragraphs explaining what it is and how it’s computed, but I really don’t feel like writing it and you probably wouldn’t want to read it. Let’s just say that nothing in life is 100% certain, so the TPU accounts for those little uncertainties.

Since the data was collected using multiple beams at a wide angle, there will be beams returning bad data, especially at the edges of the collection zone. Sometime a bad data point could be a fish, but most often bad data happens when there is an abrupt change in seafloor elevation and the beams can’t find the bottom. So, Kayla will need to manually clean out these bad data points in order to get a clean picture of the seafloor.

These data need a haircut!

Cleaned data

Almost done! Last, Kayla makes the surface. All the data points are gridded to a certain resolution based on depth (lots of explanation skipped here…you’re welcome), with the end result being a pretty, pretty picture of the bottom of the seafloor. Phew, we made it! These seafloor maps are incredibly important and have numerous applications, including fisheries management, nautical charting, and searching for missing airplanes and shipwrecks (see! I told you there would be a shipwreck!). I’ll be getting into the importance of this mapping cruise to the Channel Islands Marine Sanctuary in my final post, so stay tuned.

Shipwreck in Buzzard’s Bay, MA image courtesy of NOAA Ship Thomas Jefferson

U-boat image courtesy of NOAA Ship Thomas Jefferson

Endnote: A word about XBTs

Deploying an XBT off Shimada — Deploying an XBT off *Shimada*

Before all your data are processed, you need to know how fast the sound waves are travelling through the water. When sound is moving through water, changes in temperature and salinity can bend the wave, altering your data. An XBT is an expendable bathythermograph that is sent overboard every four hours. It transmits temperature and salinity readings throughout its quick trip to the ocean bottom, allowing the computer to make data adjustments, as needed.

Did You Know?
Hey, you’ve made it to the bottom of this post! If you are interested in seafloor mapping, have I got an institute of higher learning for you. The College of Charleston has a program called BEAMS, which trains future ocean surveyors and includes a course called Bathymetric Mappings. Three of the hip young scientists on board have taken this course and it seems to be pretty amazing. If you love sailing the high seas AND data processing, you might want to check it out.

July 22, 2005March 18, 2021

Thomas Nassif, July 22, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 22, 2005

A lionfish and two lobsters pose for the camera at Lobster Rock. Today the divers collected a total of 23 lionfish from this dive site. — A lionfish and two lobsters pose for the camera at Lobster Rock. The divers collected a total of 23 lionfish

Weather Data

Latitude: 33°38’N
Longitude: 76°55’W
Visibility: 10 nautical miles (nm)
Wind direction: 240°
Wind speed: 13 kts
Sea wave height: 1-2′
Swell wave height: 2-3′
Sea water temperature: 28.9°C
Sea level pressure: 1018 mb
Cloud cover: 6/8, Cumulus, Altocumulus

Science & Technology Log

Today the divers explored Lobster Rock, collecting a total of 23 lionfish for the flow through aquarium aboard the ship. Water from the ocean flows into and out of the tank yhrough pipes on the deck to simulate the ocean environment. This brings the total laboratory aquarium at Beaufort.

Today I also interviewed the Chief Scientist, Paula Whitfield. Most amazing to me was how her life story evolved from a childhood fascination with Jacques Cousteau to her current passion for lionfish research. Paula grew up watching the underwater videos of Jacques Cousteau, and it was at that point that she knew she wanted to become a diver. “I was a diver first, but the more I dove, the more I was formulating questions in my mind…I was curious about everything that had to do with water and marine life.” She worked for a sea grass ecologist for many years, not running the show, but she saw how the scientific process worked. Her desire to become a marine biologist grew stronger, and that’s when she decided to return to school to get her graduate degree.

Recently collected lionfish from the ocean floor are transferred to a flow through aquarium aboard the ship.

So how did Paula become one of the leading scientists in lionfish research? She responds: “It stemmed from my recreational diving – I was diving constantly in my spare time, and working for a charter boat business that attracted recreational divers from all over the world.” And then one day she began seeing lionfish off the coast of North Carolina, which was very unusual for this area. Paula knew they were Pacific fish, but she needed proof that lionfish were now in the Atlantic. “From that point on, I collected evidence was finally able to convince NOAA when a world-renown scorpion fish expert confirmed that her collected specimens were lionfish.

Once Paula was aboard a diving ship, and she was ordered to do a routine dive to the ocean bottom. The first thing she saw was right angle patterns, which hardly exist in nature. All of the sudden Paula saw a porthole lying in the sand. Back then she wasn’t a technical diver with all the fancy gear she has today. So she clutched the porthole with her knees and climbed up the anchor line. When Paula reached the surface, everyone aboard the ship stared at her in disbelief when she said: “I think it’s a wreck. I have a porthole.” She fondly remembers feeling “excited to be the first person to dive a virgin shipwreck.”

Diver and Marine Biologist Paula Whitfield swims alongside a lionfish, the focus of her research.

What Paula finds most fascinating about lionfish is how they established themselves in such large numbers in the Atlantic within a short period of time. Because of this she calls lionfish the “ultimate survivors.” But overall, she feels very affectionate towards all sea creatures, including “everything from sea spiders and feather dusters to larger fish because it’s such a different world down there. It’s important for us to know how we’re affecting that world in order to make a positive change.”

Paula’s words of advice for those who want to become marine biologists: “I think it’s important if you can become a diver – just to be able to put your head in the water to see what’s going on is more rewarding than just dropping sensors into the ocean. It opens more doors, and by seeing the environment firsthand you are able to formulate more questions about it. All this helps you become a better marine biologist, even if you don’t dive all the time.”

July 28, 2004March 18, 2021

Kathy Virdin, July 28, 2004

NOAA Teacher at Sea
Kathy Virdin
Onboard NOAA Ship Rainier
July 20 – 28, 2004

Mission: Hydrographic Survey
Geographical Area: Eastern Aleutian Islands, Alaska
Date: July 28, 2004

Latitude:58 degrees 01.110 N.
Longitude: 153 degrees 16.529 W.
Visibility: Less than 1 nautical mile
Wind direction: Light
Wind speed: Airs
Sea wave height: 0 ft.
Swell wave height: 0 ft.
Sea water temperature: 9.4 C.
Sea level pressure: 1003.9 mb.
Cloud cover: Cloudy/ foggy

Science and Technology Log

Today we have the exciting assignment of surveying the site of an 1860’s wreck of a Russian vessel. We’ll be making black and white images of the site of the wreck, giving archaeologists the depths of the whole area of wreckage. What makes this find so unusual, according to the Kodiak News, July 16, 2004, is that divers have already found a cylinder that spells out the name of the vessel “Kad’yak”. It is so rare to find an identifying object, that it happens in only about one out of a hundred sunken wreck findings. The Maritime Studies Program of Eastern Carolina University has a permit form the Alaska Department of Natural Resources, the National Science Foundation, and NOAA to do research on the site. They have sent down divers through the month of July and they have found a cannon, deck braces, a ballast pile, and three anchors. This has been identified as the oldest wreck ever found in Alaska waters. These samples all help to identify and date the wreck. After careful cleaning and preservation treatments, they will be put on display in various museums. Our survey will be a multi-beam swath survey, made from several of our launches, that will take several hours. We may not know much immediately from our survey, because all the data will need to be processed, cleaned and sent to the cartographers for charting. Perhaps we’ll read more about it in days to come in the newspapers or scientific journals.

Personal Log

I was excited to know that we were traveling through Whale Pass today and when I went out to the flying bridge to get a good look at the area, I saw a whale, quite near the ship. It was the first time I’ve seen a whale that close and it stayed on the surface for several minutes. When a whale is spotted, they make an announcement to all hands that a whale is spotted on port side or starboard side. Everyone grabs their cameras to try and get a good picture. I tried too, but I don’t know if it’ll turn out, as they are notoriously hard to film. They move through the water so gracefully and quickly that photographs are hard to come by. As we are moving through an area of straits, the weather is cloudy and foggy, but when the fog lifts, it brings a lovely view of the mountains. I’ll be headed to Homer, Alaska tomorrow for a few days of sightseeing, then home and back to the classroom. What an adventure this has been! Thank you NOAA!!

July 13, 2004March 18, 2021

Leyf Peirce, July 13, 2004

NOAA Teacher at Sea
Leyf Peirce
Onboard NOAA Ship Rainier
July 6 – 15, 2004

Mission: Hydrographic Survey
Geographical Area: Eastern Aleutian Islands, Alaska
Date: July 13, 2004

Time: 15:00
Latitude: N 55°17.29
Longitude: W 160°32.14
Visibility: 4 nm

Wind direction: 140
Wind speed: 6 knots
Sea wave height: 0 – 1 foot
Swell wave height: —
Sea water temperature: 10.0 °C
Sea level pressure: 1007.8 mb
Air temperature: 12.2 °C
Cloud cover: 8/8

Science and Technology Log

I awoke today to an announcement over the ships intercom saying, “Attention all hands, attention all hands, divers are in the water, please make sure all equipment is stored and locked”. I first checked to make sure it wasn’t me in the water, as exciting as that would have been, and then I raced out of bed to see what was going on. Apparently, since we have been anchored off the coast of Egg Island, we have had a very small oil leak. It was believed to have fixed itself after the first few hours of anchoring; however, yesterday many of the crew noticed that there was still a slick on the water off the port stern. To investigate, three NOAA certified divers dove down about 15 feet and inspected the hull of the ship. They saw that the oil was in fact coming from the left propeller, yet they could not directly identify the source of the problem, but speculate that there is a small leak in one of the o-rings. The only way to truly fix this problem is to dry-dock the boat. The closest dry-dock is in Seward, but we are scheduled to go to Kodiak first. Therefore, the plan is to see if the problem takes care of itself and if it is not better by the end of the stay in Kodiak, then take the boat to Seward. The amount of oil that is leaving the ship is very small and is escaping at an extremely slow rate. However, if this problem persists, it could become very serious.

I talked with ENS Lominkey about his dive this morning and about other dives he has made recently. He informed me that once you are NOAA certified, the equivalent of becoming a PADI or NAUI dive master, you will be allowed to help with dives that involve ship repair, tide gauge installation, or wreck surveying. In fact, only two weeks ago the RAINIER was performing hydrographic research and identified the fishing boat CONQUEST which sunk in 1994. ENS Lominkey and other certified divers dove the wreck to gather information about the wreck including its minimum depth which happened to be about 90 feet. To do this, they used a very sensitive depth gauge that relies on pressure changes. They would place this gauge at different locations on the wreck and record the various readings. ENS Lominkey also told me that they found another fishing boat wreck near the CONQUEST, but were unable to identify it. As I have developed my passion for diving over the past few years, I become more amazed at the opportunity to dive and explore uncharted waters knowing that the research you are conducting is contributing greatly to society. And, as technological advancements are made for both safer diving and better navigational charting, I can’t help but wonder how these will be further combined in years to come—a very interesting engineering design problem!

Personal Log

Today was mostly spent writing more lesson plans for my 6th, 7th, and 8th grade science classes as well as planning my 8th grade pre-algebra course. I also spent a lot of time talking with several officers about the amazing act of diving and how wonderful it would be to be paid to do something so adventuresome everyday. When sharing experiences, I did notice that the excitement of diving somewhat parallels the excitement of teaching; you never know what you are going to see, there are some dangers, but overall the experience is extremely rewarding. In both, you not only learn about other animals, or students as the case may be, but you also learn a lot about yourself, your goals and dreams, and your limits. While I am greatly enjoying my experience aboard the RAINIER, the more I think about my different classes and the students that I will see in the fall, the more excited I get about returning to the classroom!

Question of the Day:

How much oil would have to be in the water before it drastically starts harming marine life?