Scientists working at the Lagrangian Drifter Laboratory (LDL) at Scripps Institution of Oceanography and funded by the Global Drifter Program (GDP) develop new drifters and support and enhance the GDP network during research cruises from ships of opportunity and as part of regional projects coordinated with other federal agencies and sponsors. All types of  LDL drifters utilize satellite communications to relay data in real time or near-real time back through the downlink center to the data management system at the LDL.  At this time, the drifters use Iridium satellite modems and transmitters. The reporting interval and data stream are determined by the scientific use of the drifter, and the relay parameters are programmed by GDP scientists . The GDP Data Processing Center (DPC), located at the LDL, then prepares the data for further dissemination, distribution, and archiving. The GDP DPC has recently submitted an application to be recognized as the GDP Drifter Data Assembly Center (GDP-DDAC) by the World Meteorological  Organization (WMO).

The real-time data are relayed from the GDP DPC at the LDL where a redundant network of physical and virtual data servers is managed and maintained. Specifically, the Iridium satellite traffic from the GDP drifters is received by the DPC, which then decodes and archives the satellite messages and also posts the drifter data to the Global Telecommunication System (GTS) of the World Weather Watch following the latest formatting recommendations of the WMO, if allowed by the project data management plan.

The decoded data are also provided to the Global Data Assembly Centers (GDAC) that are recognized by the WMO and by the Intergovernmental Oceanographic Commission of UNESCO (IOC) and to other GDP partners, including the Data Assembly Center located at the NOAA Surface Drifter Program, for delayed mode quality control and other processing/products. The real-time data that are distributed by the GDP DPC and the LDL through the GTS are also available through the LDL/GDP website and dedicated web server interfaces.

The LDL scientists participate in many different projects sponsored by different government agencies, private sponsors, and philanthropic groups. Each government agency has a project and or agency data management and data distribution plan, and the LDL handle the data according to that plan as well as adhering to additional instructions from the program manager.

Research projects sponsored by the Office of Naval Research (US Department of Defense), the NATO Center for Maritime Research & Experimentation, and others often ask that the data be reserved for a period of time, generally up to two years or until the first publication, to permit graduate students and researchers to quality control and publish the data. After meeting the requirements of the program manager and agency and project data management plan, the data are released to the public archive. Often the agency agrees to allow the data to be transmitted to the GTS immediately and just asks that custom packaging of the data set be reserved for project scientists as described above. Agencies such as NASA and NSF may also provide data management plans or ask that data be transmitted to the GTS and public archive once collected.

For access to drifter data sets, please contact Dr. Centurioni, Mr. Braasch, or Mr. Krause and they will provide direction to the appropriate public archive or program manager. For example, a subset of the Global Drifter Program’s drifter observations, GDP Atlantic Hurricane 2021, has been made available in near-real time through the LDL’s ERDDAP data portal.  Additional data formats are available upon request.