Fig. 3. Differences in latent and sensible heat fluxes under 548 vs. 363 µmol mol^-1 CO₂ with (a) 35 g N m^-2 and (b) 7 g N m^-2 fertilization measured (symbols) and simulated (lines) from 6 to 10 Mar. 1996 (DOY 66–70). Positive values represent reductions in upward fluxes under 548 vs. 363 µmol mol^-1 CO₂