computers – NOAA Teacher at Sea Blog

July 16, 2022July 19, 2022

Laura Grimm: The Eyes of the Beast, July 16, 2022

NOAA Teacher at Sea

Laura Grimm

Aboard NOAA Ship Thomas Jefferson

July 4 – July 22, 2022

Mission: Hydrographic Survey of Lake Erie

Geographic Area of Cruise: Lake Erie

Date: July 16, 2022

Weather Data from the Bridge

Latitude: 14ᵒ 13.8’ N

Longitude: 080ᵒ 12.6’ W

Sky Conditions: Scattered clouds

Visibility: 10+ miles

Wind Speed: 9.8 knots

Wind Direction: 212ᵒ SW

Lake Temperature: 23.0 ᵒC

Wave Height: 1 ft.

Dry Bulb: 20.6 ᵒC

Wet Bulb: 16.5 ᵒC

Calculated Relative Humidity: 56 %

a section of bathymetric data (color-coded to reflect depth) within polygons overlaid on a political map of Lake Erie off of Presque Isle — Current progress of the hydrographic survey near Presque Isle, PA

Science and Technology Log

There is a lot of technology used in the science of hydrography. Each system and software have a monitor that needs to be checked and manipulated to be sure good data is being acquired. I like to call this array of monitors the “Eyes of the Beast”. At the Acquisition Desk, one can see what each of 10-15 cameras, software programs, navigational systems, and sensors are doing.

A view of 10 computer monitors set up at the Acquisition Desk — *The “Eyes of the Beast”*

A description of what each monitor is connected to will occur below the diagram. I will refer to each monitor by letter.

A grid of boxes lettered A-J (4 on top, 3 in the middle row, 3 on the bottom) — Letters I will refer to as I describe the “Eyes of the Beast”

A = This is where you will find a suite of security-like cameras on the fantail (deck at the stern or back end of the ship) that monitor various pieces of equipment. These include the MVP (Moving Vessel Profiler) and the (SSS) Side Scan Sonar. The MVP and the SSS are attached to different winches on the stern and can be used at the same time. We are currently not using the SSS because the water that is being surveyed is too shallow. The TJ will often use the SSS between 25-40 meters of water. We are surveying water with the MVP that is between 10-20 meters deep.

B = The monitor shows what is going on with a software called “Hypack”. This displays data that has been processed (it is blue and green in this picture) and coverage of data being collected real-time that has yet to be processed (yellow). Blue = water that is between 22-25 meters of depth; Green = water that is between 10-22 meters of depth. It also has the nautical chart displayed in the background showing water (light blue) and land (tan). It helps hydrographers visually keep track of what data has been taken and what still needs to be completed.

C & D = These are currently not conveying any information. They can be used when other sensors like the SSS and a different Multibeam Echo Sounder, referred to as the EM 710 (pronounced “seven-ten”), are in use.

Warning! Warning! Nerd Alert! –

The MBES that we are currently using to acquire data is more technically called the EM 2040 (pronounced “twenty-forty”). It uses between 200-400 kilohertz (kHz) of sound energy. One kHz equals one 1000 hertz (1000 Hz). Therefore, 200 kHz = 200,000 Hz. A hertz is a measurement of frequency of sound or how quickly a wave of sound moves past a fixed point. 1 hertz = 1 cycle per second. The EM 2040 can measure as deep as 300 meters. It is for higher resolution of images in shallow water.
The EM 710 emits sound energy in the range of 70-100 kHz. It is used to survey deeper waters and can image as deep as 2300 meters. The resolution is lower than the 2040.
Increasing kHz = use in shallow water with more resolution
Decreasing kHz = use in deeper water with less resolution

E = This monitor is also linked to the Hypack software. It is used to plan the survey (what “lines” to drive), show the real-time acquisition of data, and help to communicate with the bridge – letting them know where to go next. There is constant conversation between the bridge and the hydrographers in the survey room. They frequently discuss what line should the ship go to next. They also talk over the width of the lines with respect to sonar coverage (and adjust them accordingly) and plan what will happen when there are small fishing vessel or other obstructions (buoys, primarily) in the area.

F = MVPs actions and controls are shown on this monitor. The Hydrographer in Charge (HIC) can also keep an eye on the MVP by looking at camera monitor “A” explained above.

screenshot of a computer display — This is the computer that controls the MVP. The Hydrographer in Charge (HIC) does this from the acquisition desk in the Plot Room. The blue line above shows the movement of the MVP and its location in the water column. It was sent down to 1.5 meters above the floor of the lake.

G = This is the monitor for the Positioning & Attitude System (POS). It provides information with respect to the ship’s position (latitude and longitude), its direction and how it is “sitting” in the water.

Meet the Crew – Erin Cziraki (CHST)

Erin sits at the acquisition desk, with a hand on the computer mouse, looking at one of the many monitors — *Erin Cziraki, Chief Hydrographic Survey Technician (CHST)*

There is a soft spoken, ever pleasant Chief Hydrographic Survey Technician (CHST), who is great at taming the “beast”. Her name is Erin Cziraki. She supervises the survey department that is comprised of 6 members, makes the watch schedules, oversees training, is a mentor to new hydrographers as they work through their first project, compiles a lot of data for reports, and has various other administrative duties. She also stands watch at the data acquisition desk and serves as a substitute when needed. If you need assistance with trouble shooting technical problems or answers to questions regarding hydrographic data, Erin is your go to person! She is very knowledgeable, competent, and approachable.

How long have you been with NOAA? Please explain your school and career path. Erin went to college at Coastal Carolina University and majored in marine science. Her major included classes in marine chemistry, geology, physical oceanography, physical geography, and biology. After graduation, she was unable to secure employment in the field of marine science, so she entered the field of veterinarian medicine. She worked as the customer service supervisor of a veterinarian hospital for 5 years. The dream of working in marine science was ever present, so she went back to school at the local community college to obtain a degree in marine technology after which she got a job with NOAA. She has worked as a hydrographic scientist for four years.

What do you do when you are off the ship? Do you have any hobbies? Erin enjoys scuba diving (in fact, she is an instructor) and enjoys traveling.

You are a role model for others when it comes to following your dream. Thank you, Erin, for your expertise, attention to detail, and service to NOAA.

Literary Connection

Earlier this summer, I read The Lobster Chronicles by Linda Greenlaw. I came across a real-life reason for hydrographic surveys! Read this account of an early 1900s shipwreck off the coast of Maine.

“Soon they were in the midst of a howling northeaster, and a blinding snow squall. It was then that the captain decided, for the safety of his crew and vessel, which were both being wracked by the storm, to try to find safe harbor, a lee from the seas that threatened to pound men and boat to pieces. The southwestern and leeward shore of this mountainous island would have been the ideal place to anchor and wait out the gale, if it hadn’t been for the ledges that peppered the area. From Western Ear to Trail Point, vicious ledges lay just beneath the surface, while other boldly poke their heads above. These remote outcroppings of rocky peaks are surrounded by deceivingly deep water; some rocks are as far as a mile from the coast. The men, convinced that they were doomed if they remained at sea, took their chances at navigating the treacherous gauntlet.”

If only the captain had had access to a NOAA hydrographic survey of the area! He could have navigated the island safely and all souls aboard would have been saved! (Spoiler alert: they all swam to shore safely although they almost froze to death in the frigid waters!)

There are LOTS of books about adventures at sea at your local public library! One of my favorites is The True Confessions of Charlotte Doyle by Avi. Check it out!

For the little Dawgs . . .

Q: Where is Dewey today? Hint: It is important to visit this room to keep your clothes fresh and clean.

Dewey the beanie monkey sits on a grated metal surface — *Oh, no! Dewey it might be dangerous to stay in there!*

A: Dewey is in the laundry room. There are two washers and dryers available to the crew . . . soap and fabric softener are provided. We are asked to only wash full loads and not to use the washer when we are in heavy seas (periods of time when the waves are big).

LAUNDRY 3-22-2 — Sign on the Laundry Room door

Dewey the beanie monkey sits in a dryer — *Dewey in the dryer*

view of two washing machines labeled Washer #2 and Washer #1 — *I hope Dewey doesn’t go exploring and end up in the washing machine!*

Personal Log

One of the questions I have received from my family is, “What is your day like? How do you spend your time?” Well, each day, we receive a Plan of the Day (POD) from the Operations Officer (OPS). It is a schedule of what is happening on ship that day. It also assigns you your watch or duties. I use this information to plan my personal schedule. A typical day for me might look like the following (I will be stating times using a 24-hour clock):

0510 – Rise and Shine

0530 – Report to my watch as a Hydrographer in Charge in Training (HIC-IT) at the Acquisition Station in the Plot Room

0730 – my watch is over, and it is time for breakfast

0800 through 1130 – I usually work on my blog post, interview crew members, hang out on the Bridge, do whatever it takes to learn about all aspects of living and working on Thomas Jefferson. There are often meetings scheduled for the morning that I am not expected to attend.

1130 – Lunch

1200 through 1630 – I attend various safety training sessions, observe what others are doing on the ship (like yesterday when I watched the Ensigns training in the Fast Rescue Boat), safety drills, work on blog posts, etc. This is also the time when I work out in the Exercise Room, take a shower, and/or do laundry.

1630 – Dinner

1700-1930 – Continue the work that was started earlier in the day, read, play a card game, enjoy looking out at the lake, or sometimes we have a “Morale Event” like BINGO or a movie. If we have good cell phone coverage, I call my family.

1930 – Bedtime!

It is a full day! Everyday is different, and you can be sure I am learning tons and making friends. To be honest, sometimes I forget that I am on a ship, especially when the waves are small.

Ship Joke of the Day

Q: What do you call a boat owned by a bunch of football players?

A: Sportsman-ship!

June 21, 2017June 21, 2017

Helen Haskell: From Raw Data to Processed Data, June 16, 2017

NOAA Teacher at Sea

Helen Haskell

Aboard NOAA Ship Fairweather

June 5 – 26, 2017

Mission: Hydrographic Survey

Geographic Area of Cruise: Southeast Alaska – West Prince of Wales Island

Date: June 16, 2017

Weather Data

Wind: 3 knots from the east (272° true)

Visibility: 6 nautical miles

Barometer: 997.6 hPa

Air temperature: 9 °C

Cloud: 100% cover, 1000’

Location

54°54.4’N 132°52.3’W

Science and Technology Log

It would be easy to assume that once the small boat surveys are conducted and data from the larger sonar equipment on Fairweather is also acquired, that the hydrographers’ work is done and the data can be used to create navigational charts. As I have learned, pretty quickly, there are many parameters that affect the raw data, and many checks and balances that need to be conducted before the data can be used to create a chart. There are also a significant amount of hurdles that the crew of Fairweather deals with in order to get to their end goal of having valid, accurate data. Some of the parameters that affect the data include tides, salinity of the water, temperature of the water, and the density of the data.

Tides:

Tides play a huge role in data accuracy. But how do tides work and how do they influence navigational chart making? Tides on our planet are the effect on water due to forces exerted by the moon and the sun. The mass and the distance from the Earth to these celestial bodies play significant roles in tidal forces. While the sun has a much greater mass than the moon, the moon is much closer to the Earth and it is distance that plays a more critical role. Gravity is the major force responsible for creating tides. The gravitational pull of the moon moves the water towards the moon and creates a ‘bulge’. There is a corresponding bulge on the other side of the Earth at the same time from inertia, the counterbalance to gravity. The moon travels in an elliptical orbit around the planet and the Earth travels in an elliptical orbit around the sun. As a result, the positions of the moon to the Earth and the Earth to the sun change and as a result, tide height changes. The tides also work on a lunar day, the time it takes the moon to orbit the Earth, which is 24 hours and 50 minutes. So high tide is not at the same time in one area each solar day (Earth’s 24 hour day). There are three basic tidal patterns on our planet. Here is southeast Alaska, the tides generally are what is called ‘semi-diurnal’, meaning that there are two high tides a day and two low tides a day of about the same height. Other areas of the world may have ‘mixed semi-diurnal’ tides, where there are differences in height between the two high and two low tides, or ‘diurnal’ tides, meaning there is only one high and one low tide in a lunar day. The shape of shorelines, local wind and weather patterns and the distance of an area from the equator also affect the tide levels. How does this affect the hydrographers’ data? If data is being collected about water depth, obviously tide levels need to be factored in. Hydrographers factor this in when collecting the raw data, using predicted tide tables. However, later on they receive verified tide tables from NOAA and the new tables will be applied to the data.

Sound Speed Profiles:

Traveling down through the water column from the surface to the seafloor, several factors can change, sometimes significantly. These factors include temperature, pressure and salinity. These variables affect the accuracy of the sonar readings of the MBES (Multibeam Echo Sounders), so have to be factored in to account with the raw data analysis. What complicates matters further is that these factors can vary from location to location, and so one set of readings of salinity, for example, is not be valid for the whole dataset. Many fresh water streams end up in the waters off the islands of southeast Alaska. While this introduction of freshwater has effects on the community of organisms that live there, it also has impacts on the hydrographers’ data. To support accurate data collection the hydrographers conduct sound speed casts in each polygon they visit before they use the MBES. The data is downloaded on to computers on the boat and factored in to the data acquisition. The casts are also re-applied in post processing, typically on a nearest distance basis so that multiple casts in an area can be used. In the picture below, the CTD cast is the device that measures conductivity (for salinity), temperature and depth. It is suspended in the water for several minutes to calibrate and then lowered down through the water column to collect data. It is then retrieved and the data is downloaded in to the computers on board.

CTD Cast

Hydrographers Bekah Gossett and Sam Candio getting ready to deploy the cast.

Data Density:

Hydrographers also need to make sure that they are collecting enough sonar data, something referred to as data density. There are minimum amounts of data that need to be collected per square meter, dependent on the depth of the sea floor in any given area. Having a minimum requirement of sonar data allows any submerged features to be identified and not missed. For example, at 0-20 meters, there need to be a minimum of five ‘pings’ per square meter. The deeper the sea floor, the more the beam will scatter and the ‘pings’ will be further apart, so the minimum of five pings occupy a greater surface area. Hydrographers need to make sure that the majority of their data meets the data density requirements.

Crossline Acquisition:

After much of the initial raw data has been collected, and many of the polygons ‘filled in’, the hydrographers will also conduct crossline surveys. In these surveys they will drive the small boat at an angle across the tracklines of the original polygon surveys. The goal here is basically quality control. The new crossline data will be checked against the original MBES data to make sure that consistent results are be acquired. CTD casts have to be re-done for the crossline surveys and different boats may be used so that a different MBES is used, to again, assure quality control. At least 4% of the original data needs to be covered by these crossline surveys.

Shoreline verification:

Low tides are taken advantage of by the hydrographers. If the research is being conducted in an area where the low tide times correlate with the small boat survey times, then a vessel mounted LIDAR system will be used to acquire measurements of the shoreline. Accurate height readings can be extracted from this data of different rocks that could prove hazardous to navigation. Notes are made about particular hazards and photos are taken of them. Data on man-made objects are also often acquired. Below are pictures produced by the laser technology, and the object in real life. (for more on LIDAT: http://oceanservice.noaa.gov/facts/lidar.html)

Polygons on the sheet

Areas to be lazered

Notes after lazering

Laser

Old abandoned

Laser image of boat with trees behind

Old pier

Night Processing:

Each evening once the launches (the small boats) return, the data from that day has to be ‘cleaned’. This involves a hydrographer taking an initial look at the raw data and seeing if there were any places in the data acquisition that are erroneous. None of the data collected is deleted but places where the sonar did not register properly will become more apparent. This process is called night processing as it happens after the survey day. After night processing, the sheet managers will take a look at remaining areas that need to be surveyed and make a plan for the following day. By 6 a.m. the next day, the Chief Scientist will review the priorities made by the managers and let the HIC (Hydrographer In Charge) know what the plan in for their survey boat that day.

Personal Log

Throughout the Science and Technology log in this blog post, I keep referring to technology and computer programs. What stands out to me more and more each day is the role that technology plays in acquiring accurate data. It is an essential component of this project in so many ways, and is a constant challenge for all of the crew of Fairweather. Daily on Fairweather, at mealtimes, in the post survey meetings, or on the survey boats themselves, there is discussion about the technology. Many different programs are required to collect and verify the data and ‘hiccups’ (or headaches) with making this technology work seamlessly in this aquatic environment are a regular occurrence. I am in awe of the hydrographers’ abilities, not only in knowing how to use all the different programs, but also to problem solve significant issues that come up, seemingly on a regular basis. Staff turnover and annual updates in software and new equipment on the ship also factor significantly in to technology being constantly in the foreground. It often eats in to a large amount of an individual’s day as they figure out how to make programs work in less than forgiving circumstances. Tied to all of this is the fact that there is a colossal amount of data being collected, stored and analyzed each field season. This data needs to be ‘filed’ in ways that allow it to be found, and so the tremendous ‘filing system’ also needs to be learned and used by everyone.

Hydrographer Steve Eykelhoff and ET Sean checking the computers on the small boats

Taking a look to see if anything is loose

Word of the day: Fathom

Fathom is a nautical unit of measurement, and is the equivalent of 6 feet. It is used in measuring depth.

Fact of the day:

Prince of Wales Island, west of which this research leg is being conducted is the fourth largest island in the United States. 4,000 people live on the island, that is 2,577sq mi.

What is this?

(Previous post: a zoomed in photo of ‘otter trash’ (Clam shell)

Acronym of the day:

LIDAR: Light Detecting and Ranging