David Sandwell (University of California San Diego, United States); Martin Hawks (University of California San Diego, United States); Sarah Gille (University of California San Diego, United States)

Two years of SWOT data enable the construction of marine gravity fields at an 8-km spatial resolution, allowing for the detection of small seamounts approximately 1 km in height at a typical ocean depth of 4 km. These seamounts, formed by off-ridge volcanism, often exhibit a Gaussian circular shape with a characteristic height-to-radius ratio of 0.25. Using vertical gravity gradient (VGG) maps derived from SWOT’s two-year ocean height observations, we present an updated global seamount catalogue, identifying approximately 14,000 previously uncharted ones (with counting still ongoing), expanding upon the previously published catalogue of ~43,000 seamounts. Beyond their tectonic importance, seamounts also act as biodiversity hotspots, where ocean currents trap nutrients and larvae. We report observations of localized sub-mesoscale ocean dynamics adjacent to seamounts, including features consistent with Taylor columns, lee waves, and wake formations.