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<p>Western boundary currents act as transport pathways for nutrient-rich waters from low to high latitudes (nutrient streams) and are responsible for maintaining midlatitude and high-latitude productivity in the North Atlantic and North Pacific. This study investigates the centennial oxygen (<span class="inline-formula">O₂</span>) and nutrient changes over the Northern Hemisphere in the context of the projected warming and general weakening of the Atlantic Meridional Overturning Circulation (AMOC) in a subset of Earth system models included in the CMIP5 catalogue. In all models examined, the Atlantic warms faster than the Pacific Ocean, resulting in a greater basin-scale solubility decrease. However, this thermodynamic tendency is compensated by changes in the biologically driven <span class="inline-formula">O₂</span> consumption which dominates the overall <span class="inline-formula">O₂</span> budget. These changes are linked to the slowdown of the nutrient stream in this basin, in response to the AMOC weakening. The North Atlantic resists the warming-induced deoxygenation due to the weakened biological carbon export and remineralization, leading to higher <span class="inline-formula">O₂</span> levels. Conversely, the projected nutrient stream and macronutrient inventory in the North Pacific remain nearly unchanged.</p>