On October 28, 2000 the Royal Caribbean Cruise Line’s ship, Explorer of the Seas, began weekly cruises through the Caribbean from Miami. In February 2002, the Global Carbon Group at NOAA's Atlantic Oceanographic and Meteorological Laboratory (AOML) installed the first instrument to measure CO2 in surface water in the Ocean Lab on the Explorer of the Seas. At the end of 2007, operations were transitioned to a fully automated and unattended system. This transition took place over a year during which pCO2 sampling was greatly reduced to quarterly cruises. During this transition, the original pCO2 system was removed from the ocean lab and a new General Oceanics (GO) pCO2 system was installed in the bow thruster space where the other seawater instruments are located. The new location of the CO2 instrument is closer to the seawater intake, thus making the measurements potentially more accurate. The new setup also allowed the installation of an air inlet tube so that atmospheric CO2 measurements can be done in conjunction with the surface water CO2 observations.

This project represents a collaboration between AOML, the Royal Caribbean Cruise Line (RCCL) and the University of Miami’s Rosenstiel School of Marine and Atmospheric Science (RSMAS) with financial support from the National Science Foundation (NSF), the Office of Naval Research (ONR), and the National Aeronautics and Space Administration (NASA). This project provides an opportunity to gather data along repeated tracks allowing scientists to detect small changes in the ocean and atmosphere on a bi-weekly basis. A long series of high quality observations has been created that provides new insights on monthly, seasonal, and longer time cycles.

Originally the home port for the Explorer of the Seas was Miami, Florida with cruise destinations throughout the eastern Caribbean. In May 2006, the home port changed from Miami to Cape Liberty Cruise Port, Bayonee, NJ. In addition, the cruise destinations started alternating between Bermuda and the eastern Caribbean, with an occasional excursion along the northeast coast of the USA and Canada.

The data is downloaded and quality controlled at AOML, and posted to this web site. Files are arranged by year and quarter (Jan. – March, April – June, etc.) and named using the cruise designation EXyywwd.csv where yy is the 2-digit year, ww is the week number, and d is either E, W, N or S depending on whether the ship took the eastern, western, northern or southern route. Each file has an accompanying README file. Links to download the data and README files appear next to a cruise track map for each cruise that is color coded by pCO2 level. To download a particular file, select the year from the drop-down list box and click on GO. All data files for a quarter will be on one page. In addition, annual files can be accessed by clicking on the "Annual Files" link in the left-hand navigation bar.

Further information on scientific observations on the Explorer of the Seas can be found at: http://www.rsmas.miami.edu/rccl/.