Percentages of dissolved oxygen saturation (DO_sat) are plotted against percentages of pCO₂ saturation (A). Crossbar represents 100% saturation levels of pCO₂ and DO; it divides the figure into four quadrants. Of these, Quadrant I (upper left; excess DO, depleted pCO₂) suggests net photosynthesis, Quadrant III (lower right; depleted DO and excess pCO₂) suggests net respiration, and Quadrant IV (lower left, undersaturated DO and pCO₂) suggests cooling. The modeled effects of photosynthesis (PQ, green curve) and photosynthesis plus warming (PQ + Warming, blue curve) on Winter Water (WW) endmember (pink) are plotted over the observations. The subset of observations from near the DIS are also shown (lower right) along with the mCDW endmember. Inset upper right shows the data distribution following a 56 µatm adjustment in pCO₂ from sea ice alkalinity contributions. Spatial distribution of data are shown by quadrant, where Quadrant I is red, III is purple, and IV is black (B). Bathymetry, coasts, and sea ice edge are the same as in Figure 3.