Frequently Asked Questions

Any class can sign up for the program, however the user interface and classroom materials are designed with middle school and high school students in mind. Teachers are free to use or create their own materials to better support their students’ learning. Members of the public are welcome to access the program materials as well!

Data from your float will become available approximately 10 days after deployment. To observe patterns over time, we suggest waiting about one to two months for the float to collect data. There is no expiration date for accessing the data from your float, but, bear in mind that most floats have a life span of about 5 years. Fortunately, more and more floats will be deployed in the ocean in the coming years!

Adopt-a-float, Canada provides the following materials:

• sample worksheets and lesson plans to guide your interactions with your float, and others

• a glossary of common terms

• curated video playlists and learning materials from other Adopt-a-float programs

• a user-friendly data access interface

• bi-monthly newsletters with program updates

• photos and videos of floats in the lab, and in their 'natural environment' 

If there are other resources that you would like to see provided by the program, please let us know!

The United States and France have Adopt-a-Float programs as well. 

You can access your float's data in a couple ways:

1. By finding your float on our data explorer page

2. By searching for your float on this interactive map

Check out the tutorial on the data explorer page describing how to access and analyze float data in text (ASCII) or netCDF formats.

The number of floats in the ocean changes every month! Click here to see how many floats are currently in the ocean. As of July 2022, there were 482 floats deployed across the entire ocean, from ~70-degrees south to 70-degrees north.

Argo floats were first developed during the 1990s to provide open ocean data at higher density than possible from ships or fixed moorings, and more accurately than from satellites. Early versions were called "ALACE" floats. Initially, floats only measured temperature, before salinity was added to give rise to the core-Argo program. The original core-Argo program was developed to monitor ocean currents, the transport of heat and freshwater around the planet, and sea-level rise. 

SOCCOM and BGC-Argo are natural extensions of the core-Argo program that incorporate new chemical and biological sensors on Argo floats. The main objectives of BGC-Argo are to monitor the biogeochemistry of the ocean, and to document climate change impacts on the blue planet. Planning for the BGC-Argo program began as early as 2007, and was on-going until 2017. The program continues to grow towards its goal of having 1000 floats deployed ocean-wide. 

In Greek mythology, Argo was the ship in which Jason and the Argonauts set sail in search of golden fleece. Fast-forward to the 20th and 21st centuries and "Argo" floats were deployed to monitor the modern seas, alongside a recently launched satellite called JASON-1. 

Simply, more floats equals more data! Traditional oceanographic measurements (e.g., using ships) are expensive to obtain, and bad weather poses a challenge to collecting data in some regions, at some times of year. As a result, a number of ocean regions are poorly understood due to a lack of data. BGC-Argo provides year-round data coverage from all over the ocean, and therefore affords an opportunity to fill important data gaps. More floats are required to fill even more gaps, and to record ocean properties in regions that are otherwise unaccessible to humans and ships. 

A BGC-Argo float costs between about $75,000 and $190,000 USD.  The specific price depends on the float manufacturer, the number of sensors on the float and the type of battery pack. Over its lifetime, a float is usually expected to make approximately 300 to 500 profiles between 0 and 2000 m (one profile = one ascent with data collection from 2000 m to the surface), meaning that each BGC-Argo profile costs about $150 to $650 USD. 

In contrast, research vessels cost approximately $20,000 to over $100,000 PER DAY to run. If up to six profiles are obtained in a single day, then each profile costs over $3000!  

When we do the math, it's clear that BGC-Argo floats will pretty quickly become more cost-effective than research vessels! 

Yes! There are Core Argo, BGC-Argo, and Deep Argo floats. Core Argo and Deep Argo floats contain just conductivity (salinity), temperature and pressure (depth) sensors. BGC-Argo floats are able to measure chemical and biological properties as well. Core and BGC-Argo floats operate in the upper 2000 m of the ocean, while deep Argo floats can withstand depths (pressure) up to 6000 m!

In addition to different branches of the Argo program, there are also different types of floats within each branch. BGC-Argo floats have often been described as being "about the size of a 9-year-old" - and just like a 9-year-old, the floats come in a variety of shapes and sizes, depending on which company manufacturers the float. Several different manufacturers produce slightly different BGC-Argo floats, incorporating different design elements, sensor types and batteries. All BGC-Argo floats, however, must meet a high data quality standard in order to be included in the BGC-Argo program. Check out some of the different float types here.

BGC-Argo floats may contain the following sensors:

• CTD for conductivity (salinity), temperature and depth (pressure) measurements

• Oxygen optode for measurements of dissolved oxygen

• bio-optical sensors including a fluorometer for measurements of Chlorophyll, and backscattering sensors and transmissometers for measurements of phytoplankton biomass

• an ultraviolet spectrometer for nitrate measurements 

• a pH sensor to determine the ocean's acidity

• a radiometer to measure light levels

Note that not all BGC-Argo floats contain all of the sensors listed above. Read more about the sensors and the properties they measure here.

Cameras use a lot of energy.  The floats would require larger batteries - and would therefore have to be larger themselves - in order to power a camera. As-is, the float battery wouldn't last very long. Also, video footage produces a lot of data that cannot be transmitted back to land easily using satellites. Finally, a float spends most of its life outside of the ocean's "euphotic zone" (the upper part of the ocean that receives light from the sun and is typically ~100 m, or less, deep) where it wouldn't be able to capture useful images. 

Fortunately, bio-optical sensors installed on BGC-Argo floats allow researchers a glimpse into the microorganisms that are living in the ocean, by providing information on seawater chlorophyll content, phytoplankton biomass, and other unique optical signatures of different types of plankton. A recent study even reported being able to detect zooplankton, and other small organisms, using BGC-Argo floats!

Argo float cylinders are typically made of steel or aluminum. They weigh between about 25 and 50 kg (depending on type). But, far more important than the weight is the float's density, which must be very close to the density of seawater: ~1.028 kg/L.

The floats send their data to satellites at the end of each profile, and the satellites relay the data back to us on land. This process occurs one during each float profiling cycle, which occurs at approximately 10-day intervals. 

Floats and scientists 'speak' with one another using unique computer languages. The floats contain an internal computing system and processor which can be connected to a standard computer or laptop using Bluetooth or a cable. Once connected, scientists can send specific commands and queries to the float to adjust its sampling settings, read the data, or change the float's mission cycle (e.g., parking or maximum depths). The commands and float settings are then stored on the float's internal memory. Some parts of the floats's programming can be changed using satellite communication, after it has been deployed.

The goal of the BGC-Argo program is to have floats evenly dispersed throughout the global ocean. As a result, a float's launch position is often selected by examining the existing positions of floats, and by trying to predict where the float will end up. In reality, the position of the float may be selected based on the float owner's location and area of interest. For example, scientists in Nova Scotia may be most interested in deploying floats in the Northwest Atlantic Ocean and Labrador Sea. 

The floats move vertically (ascend and descend) at a rate of about 6 m per minute. At this speed, it takes about 3.5 hours to ascend from 2000 m to the ocean surface. 

The floats are deployed and designed to operate in deep waters - those deeper than 2000 m, in fact. As a result, most floats spend time far away from land or sediments, and the chance of them getting stuck anywhere is small. However, there have been records of floats getting stuck in sediments on the sea floor or under sea ice, but they eventually broke free and continued their normal operation. When either of these issues occur, scientists are unable to verify where the float is located, because it cannot relay its position information back to land via satellite. In the worst-case-scenario, a float that hits sea ice or a hard object would probably become damaged, as the sensors and satellite antenna are fragile. 

Damaged floats are rarely repaired because it costs A LOT of money to retrieve. On some occasions, a float that is malfunctioning, recording inaccurate data, or is nearing the end of its battery life may be retrieved by a passing ship. 

The floats do not make noise in the ocean, and they are generally small and light enough to pose no significant hazard to animals, or ships. Because the floats are mostly passive (they move with currents, not with active motors), it's very unlikely that a float would ever significantly interfere with marine animals. 

It's also unlikely that a predator would ever attack a float - they don't look like food, and they're probably not very palatable! However, tiny organisms (microorganisms) - like phytoplankton and algae - pose the largest threat to floats as they can attach and grow on the float's sensors. This sort of growth - called "biofouling" will often interfere with the float's measurements and if bad enough, would totally stop a sensor from working. To reduce the impact of biofouling, most floats spend most of their lives far away from the ocean surface where light promotes photosynthesis and phytoplankton growth. 

Most floats will “die” when the battery is too weak to pump the float to the surface. A small number of floats will wash up on the beach, or may even be caught in nets ("dead" or "alive"!). More commonly, however, the floats will drift around in the deep ocean until the pressure case corrodes, water leaks in, and the float falls to the sea bed. Over time on the ocean floor, the float's aluminum body will slowly breakdown into harmless chemicals which will be spread around by the ocean’s currents. The material inside, including plastics and metals, will very slowly decompose over time. Ocean currents and mixing disperse very small concentrations of pollutants, making the concentration in any given location undetectably small. 

See the “Environmental impact” page for more information on the float’s end of life.  However a small number will wash up on the beach or, very rarely, be caught in nets.  Floats have labels (in many languages) on them telling the finder, what to do with the float.

A single float deployment usually involves upwards of two people. As we noted above, the floats are fragile, and some may weigh as much as 50 kg! Usually, two people are required to carry the float safely from its box to the side of the boat. On some occasions, floats may even be deployed using a crane.

It's unlikely that climate change will affect a float's specific abilities. It is, however, possible that climate change will have an impact on the floats' trajectories. Generally, floats move about the ocean following major currents and smaller water movements called eddies. Scientists have already observed changes in the strength and paths of some currents and eddies as a result of changes in seawater temperature (density, really!) related to climate change. With this in mind, it seems likely that a float's trajectory will be influenced by the degree to which currents change in the future. 

Yes! BGC-Argo floats are helping scientists learn more and more about the ocean. Because the floats are deployed across most of the ocean, and operate year-round, they provide invaluable data that fill important gaps in our understanding of key ocean processes. Some examples of recent insights gained from BGC-Argo floats include better constraints on the Southern Ocean's role in regulating atmospheric CO2 and the discovery of large phytoplankton blooms around oceanic hydrothermal vents and following forest fires. 

The large amount of float data is also allowing scientists to calibrate and improve the performance numerical models (like in this recent study), which will eventually enable us to make more accurate predictions about future ocean conditions. Similarly, BGC-Argo float data will help to improve ecosystem models used by fisheries scientists to improve the management of important fish stocks. 

Finally, the expansion of the BGC-Argo program has also motivated the development of new sensor technology (like at this Canadian company!), which will lead to even more scientific discoveries later on.

Click here to read about some of the questions that BGC-Argo floats are helping scientists to answer.