Types of floats deployed by WHOI

Float Types

S2-A - This is a second-generation float manufactured by MRV systems and based on the design of the SOLO-II float, from the Scripps Institute of Oceanography (SIO). The S2A uses a standard Sea-Bird CTD to measure pressure, salinity, and temperature down to 2000 meters. The S2A currently makes up the majority of the WHOI fleet.

ALAMO - The Air-Launched Autonomous Micro Observer (ALAMO) is a versatile profiling float that can be launched from an aircraft ideal for deployment in the paths of hurricanes and tropical cyclones. It is similar in size and weight to an airborne expendable bathythermograph (AXBT)but can take high-resolution temperature and salinity measurements down to 1200m. This float features an RBR instrument for sampling.

ALTO - The ALTO was developed as a low-energy, high-efficiency profiling float with the capacity for additional sensors and specialized missions. It is a larger version of MRV-ALAMO float.

DeepSOLO - These floats, manufactured by MRV Systems and licensed from SIO, are capable of profiling to a depth of 6,000 meters! Like the S2As, DeepSOLO floats collect pressure, temperature, and conductivity data from which salinity can be calculated. See the OneArgo page for more information about Deep Argos.

Navis BGC - Produced by Sea-Bird Scientific, the Navis BGC is a 5-sensor  float that collects BioGeoChemical (BGC) data in the upper 2000 meters of the ocean. Integrated sensors include pH, oxygen, nitrate, and a multichannel fluorometer in addition to a standard CTD.

S2-BGC - Manufactured by MRV Systems, these 6-sensor BGC floats have the same buoyancy engine as an S2A. Integrated sensors include pH, oxygen, nitrate, a multichannel fluorometer, and a radiometer in addition to a standard CTD. See the OneArgo page for an overview of BGC Argos, and the BGC Argo home page for details about measured variables, projects, data, and more.

 

 

Earlier float types

 

Newer float models, based on the SOLO-II design, are substantially smaller than the original SOLO-I due to technological advancements. 

 

SOLO-I - The original float developed by the Instrument Development Group at SIO. Uses ARGOS telemetry, which restricts the amount of data which can be returned, so vertical resolution is somewhat coarse in deeper waters. (82 floats deployed 2001-2004)

SOLO-WHOI - (not pictured) A variant of the SOLO-I with identical hull and hydraulics to SOLO-I but with a central controller designed and programed by SeaScan Inc. Variants included different CTDs (Seabird or Falmouth Scientific) and later versions used the Iridium satellite network for telecommunications rather than ARGOS. (916 floats deployed 2003-2014)

SOLO-WHOI-DO - (not pictured) A variant of the SOLO-I with a dissolved oxygen sensor in addition to the CTD. (39 floats deployed 2007-2014)