Dataset: CTD seawater bottle data collected from the R/V Kilo Moana cruises KM2113 and KM2212 in the North Pacific Ocean in 2021 and 2022

Data were collected on the R/V Kilo Moana from August 26 to September 26, 2021 on cruise KM2113 and from September 9 to October 22, 2022 on cruise KM2212.

Conductivity, temperature, and depth (CTD) profiles and discrete seawater samples were collected near each seamount using a shipboard Seabird Electronic SBE25 profiler with salinity, temperature, depth, and dissolved oxygen sensors attached to a 24 12-liter (L) Niskin bottle rosette. Discrete seawater samples from Niskin bottles were collected at 19 different depths ranging from 10 meters (m) to 2448 m. Consistent discrete sample depths were maintained across all sites and both cruises. Discrete sample depths were selected to minimize uncertainty associated with profile calculations and were as follows: near bottom (~5 m from bottom), 1000, 950, 900, 850, 800, 750, 700, 650, 600, 550, 500, 450, 400, 300, 200, 100, 50, 10 m. For sites with bottom depth deeper than ~1500 m, additional depths were sampled every ~250 m to get a more comprehensive profile. CTD cast samples characterized the open ocean water column approximately 1-10 kilometers from each seamount summit. The distance from the seamount wall depended on the seamount slope steepness and sea state conditions. Discrete water samples collected from CTD casts 1-10 km from seamounts will be referred to as CTD samples.