Suppliers: CTD Sensors

Sea-Bird Scientific

High-Precision Sensors, Multiparameter CTDs & Integrated Systems for Marine Environmental Research & Monitoring

D-2 Inc

Conductivity, Temperature & Depth (CTD) Sensors for Oceanographic & Marine Survey Applications

NBOSI Ocean Sensors

Compact and Rugged CTD Sensors for AUVs

Teledyne Valeport

High-Precision Oceanographic Sensors & Hydrographic Measurement Solutions for Marine & Subsea Platforms

AML Oceanographic

Modular Hydrographic & Oceanographic Instrumentation for Survey, Research & Autonomous Marine Operations

Showcase your capabilities

If you design, build or supply CTD Sensors, create a profile to showcase your capabilities and connect with visitors who have an active requirement for your solutions.

Create Supplier Profile

Products

15 Cutting-edge Solutions
Add your solutions
Model 504 CTD

Rectangular CTD sensor with rear-entry permanently attached cable pigtail for ROVs & ASVs

Rectangular CTD sensor with rear-entry permanently attached cable pigtail for ROVs & ASVs
...rated pressure sensor provides depth measurement, with selectable ranges depending on configuration.... The Model 504 CTD uses a rectangular housing with integrated electronics to deliver stable...
Model 513 CTD

Cylindrical CTD sensor with integrated electronics & bulkhead connector

Cylindrical CTD sensor with integrated electronics & bulkhead connector
The Model 513 CTD adopts a cylindrical architecture with integrated electronics, delivering...
Model 511 CTD

Rectangular CTD sensor with integrated electronics & bulkhead connector

Rectangular CTD sensor with integrated electronics & bulkhead connector
...uirements. The sensor includes an integrated pressure sensor for depth measurement, with selectable... The Model 511 CTD sensor features a rectangular design with integrated electronics for reliable...
Model 501 CTD

Rectangular CTD sensor with integrated electronics & permanently attached cable pigtail

Rectangular CTD sensor with integrated electronics & permanently attached cable pigtail
...’s Model 501 sensor provides research-quality CTD (conductivity, temperature and depth) data in...
AUV CTD

Ultra low power conductivity, temperature & depth sensor for autonomous marine platforms

Ultra low power conductivity, temperature & depth sensor for autonomous marine platforms
The AUV CTD from D-2 Incorporated delivers precise conductivity, temperature, and depth data for... ...ation, the AUV CTD offers multiple mounting options and user configurable settings for sampling and...
CTD Profiler

Precision CTD Profiler for Oceanographic Platforms

Precision CTD Profiler for Oceanographic Platforms
The CTD Profiler from D‑2 Inc. is a high‑accuracy marine profiling instrument engineered to...
Hybrid CTD Sensor

High-performance conductivity, temperature & depth measurement down to 11000m

High-performance conductivity, temperature & depth measurement down to 11000m
The D-2 Hybrid CTD is a unique oceanographic instrument based on patented conductivity sensing...
UL-CTD Sensor

Ultra-low-power conductivity, temperature & depth measurement

Ultra-low-power conductivity, temperature & depth measurement
...f D-2's Hybrid CTD sensor provides the same accuracy and precision and full depth performance, with...
HydroCAT-EP V2

Compact multiparameter CTD for precise water quality analysis

Compact multiparameter CTD for precise water quality analysis
...multiparameter CTD sensor package that combines conductivity, temperature, depth, and optional...
MIDAS CTD

High-accuracy CTD profiler for longterm deployment

High-accuracy CTD profiler for longterm deployment
The MIDAS CTD is Valeport's premier CTD profiler, designed for use as a self-recording system and...
SwiFT Deep CTD

Deep-sea CTD measurement down to 6000 metres

Deep-sea CTD measurement down to 6000 metres
The SWiFT Deep CTD profiler provides direct survey-grade measurement of conductivity, temperature...
Endura-6

Infinite-endurance profiler system with six sensor ports

Infinite-endurance profiler system with six sensor ports
... this advanced profiler unlocks new capabilities for uncrewed and autonomous hydrographic survey...
MVP Roam

Moving vessel profiler designed for maximum portability

Moving vessel profiler designed for maximum portability
...(Moving Vessel Profiler) systems are designed to continuously and autonomously collect... ......ur parameters and is ideal for SV or CTD profiling. It can operate at depths of down to 60...
MVP30 V2

Smallest fixed moving vessel profiler with 185-meter cable

Smallest fixed moving vessel profiler with 185-meter cable
...(Moving Vessel Profiler) systems are designed to continuously and autonomously collect...
MVP30-350 V2

Moving vessel profiler for depths of down to 350 meters

Moving vessel profiler for depths of down to 350 meters
...(Moving Vessel Profiler) systems are designed to continuously and autonomously collect...

Conductivity, Temperature, Depth (CTD) Sensors / Profilers

Sarah Simpson

Updated:

Conductivity, Temperature, Depth (CTD) sensors are specialized devices used to measure the electrical conductivity, temperature, and depth of seawater. 

By gauging these three parameters, users of CTD profilers can infer various other properties of seawater (such as salinity and density) which are vital for understanding oceanographic processes. Through CTD surveys and profiling instruments, researchers can gain insights into marine environments. 

Rugged CTD sensor for research-quality conductivity, temperature and depth data

Rugged CTD sensor for research-quality conductivity, temperature and depth data

How CTD Sensors Work

  • Conductivity: The sensor measures the water’s ability to conduct electricity, which correlates directly with the salinity of the water.
  • Temperature: Precise thermometers within the CTD instrument measure the water temperature, providing critical data for understanding thermal stratification.
  • Depth: Pressure sensors determine the depth by measuring the weight of the water column above the device, which increases with depth.

Conductivity, Temperature, Depth Surveys

During a survey, the system is typically lowered into the water using a winch system from a research vessel. As the profiler descends, it continuously records data, which is transmitted to the surface for real-time analysis. This method allows scientists to observe the vertical structure of the ocean, detecting layers such as thermoclines and haloclines.

Applications:

  1. Climate Studies: Surveys are integral in monitoring changes in ocean temperature and salinity, which are critical indicators of climate change.
    CTD profiler with high-accuracy for deep-sea and challenging conditions

    CTD profiler with high-accuracy for deep-sea and challenging conditions

  2. Marine Research: CTD equipment is used to study the distribution of marine organisms, as many species are sensitive to specific temperature and salinity ranges.
  3. Submarine Geology: CTD monitoring helps in understanding the interactions between seawater and geological features on the ocean floor.
  4. Operational Oceanography: Conductivity, temperature, depth systems provide real-time data for naval operations, search and rescue missions, and other maritime activities.
  5. Data Collection: CTD instruments provide data that supports predictive models of ocean behavior, essential for long-term environmental monitoring and assessing human impact on marine ecosystems.

Oceanographic CTD Profiler

An oceanographic CTD profiler is deployed from research vessels and lowered through the water column to collect data at various depths. This data is essential for creating vertical profiles of the ocean’s physical properties. These profiles help scientists understand ocean circulation, thermohaline dynamics, and biological processes.

Profiling CTD Instruments

A profiling CTD instrument is often used in conjunction with other oceanographic instruments to provide a comprehensive view of the marine environment. These instruments are typically mounted on a rosette sampler, which can collect water samples at different depths simultaneously, enhancing a survey’s effectiveness.

Advanced Conductivity, Temperature, Depth Systems
Modern conductivity, temperature, depth systems are equipped with additional sensors to measure parameters like dissolved oxygen, chlorophyll, and turbidity, offering a more comprehensive understanding of marine environments. These advanced sensors are crucial for interdisciplinary studies combining physical oceanography, marine biology, and biogeochemistry.

Related Articles

NBOSI 500 Series CTD Sensors Provide Research-Quality Oceanographic Measurements

NBOSI’s 500 Series CTD sensors combine compact construction, precision electronics, and configurable designs to provide research-quality oceanographic measurements for subsea integration applications

May 13, 2026
Oi26 Interview: In-Situ Highlights RDO Trio & Water Quality Monitoring Platforms

In-Situ spoke to OST at Oceanology International 2026 in London, with Principal Technical Consultant and Chief Hydrologist Adam Hobson outlining the company’s water quality monitoring platforms and new compact sensing technology

Mar 18, 2026
RBR Launches RBRduraturo⁴ for High-Frequency & Long-Duration Ocean Monitoring

The new RBRduraturo⁴ from RBR features a 100mm form factor designed for massive battery capacity and independent sensor sampling

Mar 17, 2026
Sea-Bird Scientific Sensors Reveal Ocean-Driven Melting Beneath Thwaites Glacier

British Antarctic Survey researchers used Sea-Bird Scientific’s SBE 49 FastCAT CTD and PDIM beneath Thwaites Glacier to examine how ocean-driven melting influences Antarctic ice loss and future sea-level rise

Nov 05, 2025
D-2 Unveils Hybrid AUV-CTD Sensor for Underwater Vehicle Navigation & Data

D-2's new conductivity, temperature, and depth sensor features a two-electrode hybrid design and fast sampling for UUVs and Gliders

Oct 24, 2025
D-2 to Showcase Titanium CTD & New AUV CTD at Oceans 2025

D-2 Inc. is set to highlight its latest CTD technology at Oceans 2025 in Chicago, presenting the AUV CTD and Titanium Ocean CTD with enhanced precision and integration features

Sep 26, 2025
Pumped Flow & CTD Synchronization for Accurate Oceanographic Research

Sea-Bird Scientific explores pumped flow technology, highlighting the importance of accurate Conductivity-Temperature-Pressure (CTD) measurements for salinity and density, and its reliability and efficiency in long-term deployments

Sep 04, 2025
Sea-Bird Scientific’s HydroCAT-EP V2 CTD Integrated with Origin 600 ADCP

Sonardyne has integrated Sea-Bird Scientific’s HydroCAT-EP V2 multiparameter CTD sensor with the Origin 600 ADCP, allowing sensor measurements to be merged with ADCP data and transmitted acoustically to the surface

Aug 14, 2025
Ultra-Compact CTD Profiler for Deep Ocean Sensing

D-2's ultra-compact Conductivity, Temperature, Depth (CTD) profiler delivers precise deep ocean data with low power use, easy integration, and real-time or standalone operation

Aug 13, 2025