NOAA OAP Seasonal pH Glider Groundtruthing

This project conducted seasonal glider deployments to investigate carbonate chemistry and monitor ocean acidification in the Mid-Atlantic Bight. Gliders were deployed with an integrated deep rated version of the Ion Sensitive Field Effect Transistor (ISFET)-based pH sensor. The pH sensor unit was complemented with existing glider sensors including a Conductivity, Temperature, Depth (CTD), a WETLabs FLBBCD ECO puck configured for simultaneous chlorophyll fluorescence and optical backscatter measurements, and an Aanderaa Optode for measuring dissolved oxygen. This is the comparison between pH data recorded by gliders and discrete water samples taken at glider deployments and recoveries. Full-resolution glider datasets can be downloaded via the National Centers for Environmental Information (NCEI) Ocean Carbon and Acidification Data System (https://www.ncei.noaa.gov/products/ocean-carbon-acidification-data-system).

cdm_data_type = Point
VARIABLES:
obs
glider_trajectory
time (Time (Glider), seconds since 1970-01-01T00:00:00Z)
sampling_time (Time (Water Sample), seconds since 1970-01-01T00:00:00Z)
longitude_glider (Longitude (Glider), degrees_east)
latitude_glider (Latitude (Glider), degrees_north)
longitude (Longitude (Water Sample), degrees_east)
latitude (Latitude (Water Sample), degrees_north)
cruise_type
cast_number
distance (m)
depth (m)
pH_glider (pH (Glider), 1)
pH_discrete (pH (Water Sample), 1)
pH_diff (pH Difference, 1)
TA_glider (Total Alkalinity (Glider), micromoles kg-1)
TA_discrete (Total Alkalinity (Water Sample), micromoles kg-1)
TA_diff (Total Alkalinity Difference, micromoles kg-1)
... (5 more variables)


pH Glider Carbonate Chemistry Water Sampling

For each project, underwater Slocum gliders were deployed with an integrated Conductivity, Temperature, Depth (CTD) and deep rated version of the Ion Sensitive Field Effect Transistor (ISFET)-based pH sensor as well as other sensors. Water samples were taken during deployment and recovery to ground-truth the glider-based pH sensor. Full-resolution quality-controlled glider datasets can be downloaded via the National Centers for Environmental Information (NCEI) Ocean Carbon and Acidification Data System (https://www.ncei.noaa.gov/products/ocean-carbon-acidification-data-system). Full-resolution raw glider datasets with associated QC variables can be downloaded at https://slocum-data.marine.rutgers.edu/erddap/index.html.

cdm_data_type = Point
VARIABLES:
time (seconds since 1970-01-01T00:00:00Z)
latitude (degrees_north)
longitude (degrees_east)
project
station_id
glider_trajectory
deployment_recovery
cast
niskin
depth (m)
temperature (Sea Water Temperature, degree_C)
salinity (Sea Water Salinity, 1)
pH (1)
pH_stdev (pH Standard Deviation, 1)
TA (Total Alkalinity, micromoles kg-1)
TA_stdev (TA Standard Deviation, micromoles kg-1)
DIC (Dissolved Inorganic Carbon, micromoles kg-1)
DIC_stdev (DIC Standard Deviation, micromoles kg-1)

Rutgers University, University of New Hampshire, Stony Brook University