Meredith Salmon: Let The Surveying Begin! July 15, 2018

NOAA Teacher at Sea

Meredith Salmon

Aboard NOAA Ship Okeanos Explorer

July 12 – 31, 2018

Mission: Mapping Deep-Water Areas Southeast of Bermuda in Support of the Galway Statement on Atlantic Ocean Cooperation


Weather Data from the Okeanos Explorer Bridge

Latitude: 28.12°N

Longitude: 62.04°W

Air Temperature: 27.0°C

Wind Speed:  14.08 knots

Conditions: Rain and clouds

Depth : 5133.67 meters

Science and Technology Log

Hypack for Line Planning 

This morning, we learned how to upload a variety of planning lines for the survey that will be conducted for the Atlantic Seabed Mapping International Working Group (ASMIWG) established area Southeast of Bermuda.

The black circle pictured on the map below is Bermuda’s Exclusive Economic Zone (EEZ). Bermuda’s EEZ is an area of ocean within 200 nautical miles of the island that covers 464,940 km2 of ocean. Under the United Nations Convention on the Law of the Sea, Bermuda has special jurisdiction over the use and exploration, management, and conservation of those resources. According to Bermuda’s Department of Environment and Natural Resources, this zone was established in 1996 and this distinction allows Bermuda to gain important economic value from these resources.


Bermuda's EEZ
The black circle pictured above is Bermuda’s Exclusive Economic Zone. The red line is the outline of the survey area and the green lines are previously collected data that will be considered when the Okeanos Explorer collects new mapping data.

The red line (ASMIWG Galway mapping box) displayed on the screen is the outline of the survey area. This area is 145,120 km2; however, during this expedition, we will be mapping a quarter to a third of the region. Within the survey area are small blue lines that are considered to be planning lines. These lines were crafted on the computer using Hypack and are 180 nautical miles in length. For efficiency, it is important for them to be oriented to follow the contour lines, and to be long because it requires less turns, which saves time while mapping. The distance between the lines is 4,300 meters and may be subject to change at the discretion of the mapping team.

The green lines are existing multibeam or bathymetric data in the region. This is crucial information to consider because the Okeanos Explorer’s goal is to map what has not been investigated and combine it with the data that already exists in those areas. The previously collected data was recorded from a variety of ships such as Atlantis, Healy, and Knorr, so we will use our EM 302 sonar to edge match their data.

In addition to the existing data, there is a background telemetry layer (blue background) that shows satellite measurements to predict what the seafloor may look like. Scientists use the existing data to update the layers to create a more accurate depiction of the seafloor.

So far, the data collected in transit has been very reliable due to weather conditions and the flat abyssal seafloor. As survey data is incoming, the personnel on watch must ensure that the sonar and computer systems are operating correctly. We will begin the actual surveying this afternoon once we reach the first line!


Line Plans in Hypack
Red 180 nautical mile planning lines created for the survey area in Hypack


Personal Log

Now that we have begun the survey, everyone is busy collecting, processing, cleaning, and updating data files in the Mission Control room. We have been learning all about the software used to create files, and it is very interesting to learn how all of the different systems are being used to make sense of the data from multiple sources (ex. EM 302, EK 60, and sub-bottom profiler). Everyone on board is really enjoying each other’s company and is eager to collaborate to help one another learn. It is really fun! One of the best parts of being in the middle of the ocean has definitely been watching the sunsets. They are incredible!

sunset 7.14.18
7/14/18 Sunset
sunset 7.15.18
7/15/18 Sunset

Did You Know?

The Sargasso Sea is considered to be one of the great ecological wonders of the world! It is home to golden algae known as Sargassum. This algae serves as a floating habitat and provides food, refuge, and breeding grounds for an array of marine organisms such as fish, sea turtles, marine birds, crabs, shrimp, and more!

The Sargasso Sea is the only sea in the world surrounded by currents, rather than land and Bermuda is the only island within it.

The algae directly benefits Bermuda when it washes ashore and sinks into the sand since it fertilizes the soil and protects the island against storms and erosion.

Sargassum off the side of the bow


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