In this project, we leverage the near-monthly, 5-day long expeditions to oligotrophic waters approximately 100 km from Oahu, Hawaii, conducted by the Hawaii Ocean Time-series (HOT) program. We will participate in ~30 HOT cruises across all seasons over a 3-year period, amounting to ~ 150 days of high-quality collection of a suite of essential parameters for PACE Mission validation.

Rapid response field campaigns (small boats, small crew) to measure radiometry in the Santa Barbara Channel when sea and sky conditions are optimal for matchups. Process and deliver in situ high quality radiometric data for the validation of the reflectance data product of the PACE OCI instrument.

This project will collect high-quality, bio-optical, and biogeochemical data for validation of advanced satellite products from PACE OCI for the Arabian Sea, a highly under-sampled region of the worlds oceans, now experiencing dramatic ecosystem changes from human activities and climate-change. Over the past two decades, the base of the food chain of this monsoonal-driven ecosystem has transitioned from diatoms to one dominated by the mixotrophic dinoflagellate, Noctiluca scintillans (Noctiluca) that forms intense and widespread blooms visible from space. Capturing such phytoplankton transitions has been the pursuit of ocean color missions for more than three decades, and with its hyperspectral capabilities, NASAs PACE mission can now provide unprecedented insight into the response of phytoplankton communities to global pressures. Despite the dramatic rates at which the Arabian Sea has been changing, it remains among the most optically under-sampled of global water bodies. As part of this effort, we will leverage our long-standing ties with colleagues in India to collect high quality, high resolution (sub-pixel scale), continuous, underway and discrete bio-optical measurements to validate standard and advanced ocean products from PACE, essential to advance our understanding of vulnerable marine ecosystems and their response to anthropogenic change. As part of this activity, we plan to participate in one pre-monsoon cruise (2025) led by Space Applications Centre, ISRO, India, and two post-bloom ONR led cruises in April-May of 2024 and in April-May 2025. The pre-monsoon cruises are being undertaken as part of an Indo-US study focused on establishing triggers of the southwest monsoon rainfall season over the Indian sub-continent. Some of the data shared under this DOI is part of the Arabian Sea Marine environment through Science and Advanced Training (EKAMSAT) collaborative effort between the Ministry of Earth Sciences, Govt. of India and the Office of Naval Research. EKAMSAT commenced with a pilot study in June 2023. The pilot data is being archived under the SeaBASS experiment EKAMSAT_Pilot_ASTRAL (DOI: 10.5067/SeaBASS/EKAMSAT_Pilot_ASTRAL/DATA001) and can downloaded here: https://seabass.gsfc.nasa.gov/experiment/EKAMSAT_Pilot_ASTRAL.

The Salinity and Stratification at the Sea Ice Edge (SASSIE) project is a NASA experiment that aims to understand how salinity anomalies in the upper ocean generated by melting sea ice affect sea surface temperature (SST), stratification, and subsequent sea-ice growth. SASSIE involved a field campaign that sampled the transition from summer melt to autumn ice advance in the Beaufort Sea during August-October 2022, making intensive in situ and remote sensing observations within ~200km of the sea ice edge. The Passive-Active L-Band System (PALS) is an airborne microwave radiometer that senses ocean temperature and surface wind speed. The brightness temperature data is obtained at 1.4GHz using the PALS conical scanner, with the raw data sampled at 1ms and gridded over an approximate 2x2km grid. Several quality control steps were done to remove any scan dependent biases, radio frequency interference, wind-speed dependencies. Calibration of the sensor was done with respect to special aircraft maneuvers as well as in-situ samples. Brightness temperature were converted to salinity via the Klein-Swift salinity retrieval model. Data is available in netCDF format.

The Salinity and Stratification at the Sea Ice Edge (SASSIE) project is a NASA experiment that aims to understand how salinity anomalies in the upper ocean generated by melting sea ice affect sea surface temperature (SST), stratification, and subsequent sea-ice growth. SASSIE involved a field campaign that sampled the transition from summer melt to autumn ice advance in the Beaufort Sea during August-October 2022, making intensive in situ and remote sensing observations within ~200 km of the sea ice edge. This dataset contains ocean temperature and salinity data collected by surface drifting buoys (called UpTempO or Hydrobuoys, interchangeably) deployed in the Beaufort Sea. Each buoy has a different configuration of sensors, and records to a maximum of 60 m depth. Drifters were left at sea after the completion of the field deployment and are recording data into March 2023. Version 2p data has major quality control performed. Data are available in netCDF format.

The APERO project proposes a mechanistic approach to the biological carbon pump (export of surface biogenic carbon production and fate in the water column -200/2000m). APERO aims to reduce the gap between the amount of photosynthetically produced organic carbon transferred to the deep ocean and the metabolic demand for carbon in the water column. The project is built around a campaign with two oceanographic vessels in the Northeast Atlantic, at the level of the British permanent station PAP (58N, 16W). It lasted 40 days and took place in June and July of 2023, at the time of maximum particulate carbon export to the deep ocean. The three major contributions of APERO are the study of the role of small-scale dynamics (~1-10km) on the water column using autonomous platforms, imagery and innovative instrumentation, the construction of a comprehensive database based on the simultaneous multidisciplinary observation of all processes regulating the attenuation of carbon flux in the water column and the quantification of the fluxes associated with these processes. Relying on a significant international collaboration with the JETZON consortium (https://www.jetzon.org/) and an ambitious observation strategy, complemented by molecular biology and innovative modeling approaches, this study will contribute to a significant reduction of uncertainties on carbon storage by the ocean.

For two consecutive years (2023-2024), the schooner Tara is participating in the study of coastal ecosystems all along the European coast. The sampling of Tara Europa is part of the TREC expedition Traversing European Coastlines, led by the European Molecular Biology Laboratory (EMBL) in collaboration with the Tara OceanS consortium, the Tara Ocean Foundation and more than 70 scientific institutions. Its objective is to study the land-sea interface, where biodiversity meets numerous pollutions.

This dataset contains model output from the Navy Coastal Ocean Model (NCOM) run during the Sub-Mesoscale Ocean Dynamics Experiment (S-MODE) field campaign. S-MODE aims to understand how ocean dynamics acting on short spatial scales influence the vertical exchange of physical and biological variables in the ocean. NCOM model output consists of daily files during the deployment dates of the pilot campaign in Fall 2021, IOP1 in Fall 2022, and IOP2 in Spring 2023. Data consists of ocean variables such as salinity, sea water temperature, water depth, and surface wind stress, and are available in netCDF format.

Data will be provided for above water radiance measurements in the hyperspectral and multi-spectral polarization modes using a system containing a hyperspectral imager (Cubert, Germany) and multi-spectral polarimetric imaging camera (Teledyne Dalsa) with additional color filters. For this experiment data will be provided for the system installed on the helicopter at 10 stations in Aug 2022 over Chesapeake Bay at 4 heights from 60 to 750 m. Complimentary data from handheld GER spectroradiometer and ac-s flowthrough measurements near same stations with 1-2 hours delay from the boat will be also provided. Similar data were submitted to SeaBASS as a part of the VIIRS validation experiment and can be found under the DOI: 10.5067/SeaBASS/VIIRS_VALIDATION/DATA001.

Bio-GO-SHIP aims to become an international collaboration to measure, understand, and predict the distribution and biogeochemical role of pelagic plankton communities. The project leverages the global-reaching [GO-SHIP](https://www.go-ship.org/) platform and its complementary hydrographic measurements. The mission of Bio-GO-SHIP is to quantify the molecular diversity, size spectrum, chemical composition, and abundances of plankton communities across large spatial, vertical, and eventually temporal scales. This will be achieved through systematic, high-quality, and calibrated sampling of omics, plankton imaging, particle chemistry, and optical techniques as operational oceanographic tools. Integration with regular GO-SHIP measurements and their analyses of the physical and chemical environment will allow us to understand (and eventually predict) how plankton communities respondto ocean changes and how biological processes feeds backon carbon, oxygen and nutrient cycles.