| Summary: | We compiled a time series spanning the period from 1996 to 2019 of the seawater hydrographic variables conservative temperature ( o C), absolute salinity (g kg –1 ) and dissolved oxygen (μmol kg –1 ), and the macronutrients DIN (nitrate +nitrite +ammonium), phosphate, and silicic acid (μmol kg –1 ). The study area covered the northern Antarctic Peninsula regions including the Gerlache Straitand the western, central, and eastern basins of Bransfield Strait. Most data (~90%) were obtained from the Brazilian High Latitude Oceanography Group (GOAL; http://goal.furg.br/) from austral summer field campaigns (January-March). In some years (1996, 2005, 2006, 2010, 2011) we used hydrographic and macronutrient data from GLODAP 2020 (Olsen et al., 2020) along the NAP and exceptionally for 1996 we used data available from December 1995 to February 1996 (the FRUELA cruises, García et al., 2022; Álvarez et al., 2002).Details on the sampling and analysis of macronutrient data obtained from GLODAP dataset can be accessed on the OCADS platform ( https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system-portal/ ). About 97% of the DIN data were composed of nitrate, followed by ammonium (2%) and nitrite (1%). Therefore, in some cases (11% of all data), we considered DIN as the nitrate concentration, when no nitrite and/or ammonium data were available. Discrete seawater samples were collected at irregular depth intervals from surface (5 m) to deep waters (at approximately 15 m from the bottom). We averaged the parameters for each region at regular depth intervals from the surface to the bottom (i.e., 0, 25, 50, 75, 100, 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2500 m) to obtain an averaged summer profile for each year. All sampling and analyses informationof the hydrographic and macronutrientsare detailed in Kerr et al.(2018), Mata et al.(2018), Dotto et al.(2021)and Costa et al. (2020), and references therein. The BGQ_NAPv1.0. binned data set was created by the Brazilian High Latitude Oceanography Group ...
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