AOML's Ocean Chemistry and Ecosystems Division

About the Equinox

Image of the Equinox

In 2000, Royal Caribbean International started a collaboration with the University of Miami's Rosenstiel School of Marine and Atmospheric Science (RSMAS), the National Oceanic and Atmospheric Administration (NOAA), the National Science Foundation (NSF), the Office of Naval Research (ONR), and the National Aeronautics and Space Administration (NASA) to have one of its ships, the Explorer of the Seas, equipped with a whole array of scientific instruments geared toward monitoring the atmosphere and the ocean.

In February of 2002, our group installed an autonomous instrument on this ship to measure CO2 in the surface water. We have been collecting data in the Caribbean region, where the Explorer of the Seas mainly sailed, since that date and up until Royal Caribbean International relocated the ship to Asia in February of 2015.

In order to continue our unique data set in the Caribbean region, we were graciously allowed to install a system on board the Equinox which, during the winter time, has a very similar route to the one the Explorer of the Seas was following. In the summer time, the Equinox crosses the Atlantic and sails around the Mediterranean Sea until it returns to the Caribbean in the Fall.

The system was installed in February of 2015 and the first data collected on the 24th of that month. The last data collected on the Explorer of the Seas was on February 15, allowing only a 10-day gap between the two data sets. The installation is a partnership with RSMAS who not only provides the seawater supply infrastructure to which our system is connected but also the computer network to allow the constant access to the system computer and data. The pCO2 instrument takes 5 air and about 100 water measurements about every 4 hours. Data files are transferred to AOML every day so that the system operation can be monitored. The final data are processed after a cruise is completed and then posted to international databases and to this web site.

About this Website

This web site provides access to the fugacity of CO2 (fCO2) data collected on this ship. Note, fCO2 is the partial pressure pCO2 corrected for non-ideality of the CO2 gas; they are numerically similar (fCO2 ≃ 0.995 pCO2). The processed data are organized by year and by cruise. For each cruise, the color coded fCO2 values are plotted along the ship's cruise track on a chart. Next to each chart are links to the comma-delimited data file and the associated Readme file. To download a data file, select the year from the drop-down list box and click on GO. Choose a chart and cruise, right-click on the link to its data file or Readme file, and select the download option. Please consult with and acknowledge the AOML Ocean Carbon Cycle group if data is used for publication or presentation (contacts in Master Readme, or

The Master Readme link in the menu bar on the left provides meta data that is applicable for all data gathered from this ship. The individual Readme files next to the charts provide meta data specific to the associated cruise. The Realtime Display link displays plots of the raw xCO2 data as a function of time and location. These plots are suitable for monitoring but are not suitable for environmental interpretation since the Realtime data has not been processed nor quality controlled.