Dataset Submitted

Multi-point temperature profiles across the flank of the Corpus Christi ship channel, along with synoptic data from experimental sensors for conductivity, dissolved oxygen, and turbidity proxy.

Authors: Breier Jr., John A, John.Breier@utrgv.edu
Identified On: Jan 10 2025 22:09 UTC
DOI: https://doi.org/10.7266/8f3ket21
UDI: O1.x297.000:0001
Project Information

Funded By:
Texas OneGulf

Funding Cycle:
Texas OneGulf 2023

Research Group:
An Observational Study of Ship Channel and Shallow Bay Interactions and their Influence on Sediment Transport, Mixing, and Water Quality in Corpus Christi Bay

Point of Contact

John A. Breier Jr.
University of Texas Rio Grande Valley
John.Breier@utrgv.edu

Data Collection Period
2024-08-29
to
2024-09-27
Theme keywords

water quality, mixing, ship channel, water temperature

Abstract:

This water quality dataset was collected in the Corpus Christi ship channel using an experimental array of water quality nodes during three separate multi-day periods between August and September of 2024. This was part of a project designed to lend insight into exchange dynamics between the ship channel and Corpus Christi Bay.

Suggested Citation:

Breier Jr., John A, John.Breier@utrgv.edu. Multi-point temperature profiles across the flank of the Corpus Christi ship channel, along with synoptic data from experimental sensors for conductivity, dissolved oxygen, and turbidity proxy.. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/8f3ket21

Purpose:

To better understand the influence of physical mixing-related processes in and around ship channels on multiple environmental stressors, this project developed new observation tools and techniques to observe exchange dynamics in ship channels and put them to initial use in Corpus Christi Bay.

Data Parameters and Units:

Water Temperature, Water temperature in degrees Celsius Absolute Pressure, Atmospheric pressure in millibar, recorded by the nearby NOAA monitoring station 8775237 in Port Aransas. Dissolved Oxygen, Dissolved oxygen in percent saturation, qualitative see accompanied technical report. Turbidity Proxy, An experimental proxy sensor for turbidity, qualitative see technical report. Water Pressure, Water pressure relative to atmospheric pressure in millibar. Depth, Water depth in meters, calculated using the TEOS10 equations of state, adjusting for latitude and atmospheric pressure.

Methods:

Field observations were collected by deploying the new sensor array during three different multi-day periods (A, B, and C) in Corpus Christi Bay during August and September of 2024. Because this was a new system and we were deploying it across the edge of the ship channel, we only deployed it when we could be present with it and recover it as needed. This meant for this project we conducted daytime deployments only, deploying the array in the morning and recovering it in the afternoon, and repeating the process for each day. Also, because the array was new and we were experimenting with new lower cost sensors and components and developing and optimizing deployment methods for deploying the moorings across the edge of the ship channel, several of the initial days were occupied with engineering development. Observation days were also lost during period B due to weather related to a nearby tropical storm. From these three periods we collected five days of observations (Table 1). The deployments were made in two separate areas along the Corpus Christi ship channel (Figure 3). The first location (Area 1) was used during period A. The second location (Area 2) was used for the subsequent deployments as it was closer to the launch site for our support boat. In both cases the array was deployed at the northern edge of the ship channel. During period A, we deployed the sensor elements leading up to the edge of the channel. During the subsequent deployments we deployed the sensor elements across and into the channel so that the deepest sensor node was near the bottom of the channel flank. The sensor array consisted of a surface base node and three connected custom sensor nodes. The surface base node contained a single board logging and control computer, cell modem, WiFi modem, GPS, real time clock, and battery for the entire array. A submersible tether connected the surface node to all three sensor nodes in series, supplying them with power and polling them for data which it then logged. We were able to monitor the data from the boat remotely by both WiFi and cellular connection. The sensor array was completely custom. Developing a completely custom array allowed us to experiment with lower cost sensors with the goal of reaching a design that we can iterate on in the future and use in a wider range of applications in our large Texas Bays and increase our observational capacity. It also allowed us to focus on a system that was relatively lightweight and easy to deploy, this was considered important for operations at the edge of the ship channel where changing conditions and ship traffic might require us to remove it on short notice. The array tether was approximately 50 m long. Technically it could have been over 500 m long but this was sufficient for this application and the longer the cable the more difficult to deploy. The array could also accommodate more sensor nodes (there is no strict limit on how many), but three was sufficient in this case. As we were testing lower cost experimental sensors, the 50 m length allowed us to focus resources on optimizing and maintaining the sensor selection for these nodes. The sensor nodes were equipped with sensors for temperature, pressure, conductivity, dissolved oxygen, and a combination optical sensor for reflectance and color which we are testing for a low cost turbidity proxy sensor. Depth was calculated from pressure using the TEOS10 equations of state, adjusting for latitude and atmospheric pressure as recorded at the time by the nearby NOAA monitoring station in Port Aransas.

Instruments:

The sensor array consists of a surface base node and three connected custom sensor nodes. The surface base node contains a single board logging and control computer, cell modem, WiFi modem, GPS, real time clock, and nickel metal hydride battery for the entire array. Each sensor node contains Blue Robotics temperature and pressure sensors, Atlas Scientific dissolved oxygen and conductivity sensors, and an Atlas Scientific color reflectance sensor. The sensor nodes also contain their own microcontrollers, separate electronic control boards for both the dissolved oxygen and conductivity sensors, and their own back up batteries. A submersible tether connects the surface node to all three sensor nodes in series, supplying them with power and polling them for data which it then logged. The components are connected to one another by the cable, which in this case was 50 m long, but technically can be several hundred meters long. The components are also connected to weights and surface marker buoys to anchor them in place. Once arranged on deck and powered on the entire array can be deployed and recovered in minutes by two people on deck. The base node operating system was the Rasbian Linux variant. Programming of the array data logging operations was in Python. The microcontrollers were programmed in C++. Communication between the sensor nodes and the base node used the CAN FD communication protocol. The basenode controlled the frequency of the observations and polled the nodes for data typically every 10 seconds. The deployments typically lasted 6 hours but the battery could have supported operations for several days or more if the frequency of data collection was reduced.