EARTHCARE+ INNOVATION – OREO

Key nutrients deposited in the ocean, including nitrogen (N), phosphorus (P), silica (SiO₂), and iron (Fe), are essential for regulating phytoplankton growth, affecting marine productivity, ocean colour, and the ocean’s capacity to absorb greenhouse gases, as in the case of atmospheric CO2. Among these nutrients, iron (Fe) availability across large oceanic regions of the Earth is considered the most important limiting factor for phytoplankton growth. Over these open oceanic regions, the main source of iron is the aeolian transported mineral dust, serving as the primary source of nutrients, thereby regulating phytoplankton growth and ocean productivity.

The European Space Agency (ESA) “Ocean Research enhancement through EarthCARE Observations of dust” (OREO) activity aims to leverage on state-of-the-art Earth Cloud Aerosol and Radiation Explorer (EarthCARE) observations and optical products to shed more light on atmospheric dust interaction with the ocean and to improve our understanding on the dust impact on the sustainability of marine ecosystems.

More specifically, to-date, a major open scientific question characterized still by high uncertainties in the dust cycle is the quantification of the actual amount of dust that is deposited into the open ocean. Thus, improving our current state of knowledge on the quantification of atmospheric dust deposition and the corresponding variability across the ocean is essential for addressing unresolved questions related to dust’s biogeochemical impacts on marine ecosystems and climate.

OREO’s challenge is to bring ESA/JAXA EarthCARE observations and optical products together with diverse existing satellite-based Climate Data Records (i.e., ESA-DOMOS and ESA-LIVAS), advanced modelling outcomes (i.e., MONARCH and EC-Earth3), other novel observations (i.e., NASA-EMIT and CALIPSO), and in-situ information. Towards these overarching objectives and capitalizing on the huge EO-based potential offered by EarthCARE capabilities, OREO establish a full four-dimensional (4D) reconstruction of the global atmosphere system relevant to dust aerosol, including quantification of dust deposition along the ocean and the marine ecosystems.

The overarching objective of the activity is to advance our fundamental understanding of the processes governing dust aerosol deposition, by exploiting the above EO-based, modelling, and in-situ datasets in an integrated approach. Through enhancing our understanding on the role of atmospheric-deposited iron-containing mineral dust into the ocean, through comparison with ESA – Climate Change Initiative (CCI) provided Chl-a and POC timeseries, the ESA activity aims to bridge major knowledge gaps in ocean sciences with respect to the complex processes governing the role of the oceans in the Earth and climate system, the marine biology and ecosystems and advance our capacity to better understand and describe complex and poorly understood processes on ocean-land-atmosphere interactions.