1. Proposed 5 sections for model, observed data plot 4 of 5 section followed Monique Messié’s vertical_sections1.ppt. One section added following Francisco’s recommendation. Section 1 horizontal, section 3,4,5 all parallel to each other. Section 2’s angle is somewhere between. If have more definitive location, please modified it.

3. Terminology MLD: Mixed layer depth, increase of potential density 0.1 kg/m^3. PYC: pycnocline depth, 25.5 sigma_theta depth MDD: maximum density gradient depth. M25: Mixed layer depth, increase of potential density 0.25 kg/m^3. M50: Mixed layer depth, increase of potential density 0.50 kg/m^3.

4. Pycnocline 25.5 kg/m^3 defined pycnocline quickly decreases in winter cooling process, and eventually potential density in the water column > than 25.5 kg/m^3. 26.0 km/m^3 depth is deeper, but similar flaw in winter time. PYC is very good indicator of the bottom of pycnocline at least locally, if without flaw. How about maximum density gradient depth (MDD). Or 0.5 kg/m^3 difference (M50)?

5. Maximum density gradient depth Patchy. Smoothed by calculating MDD after interpolating density to a finer resolution vertically. Both essentially the same. MDD value is very close to M50, especially in summer. MLD, M25, M50 all show a very similar spatial pattern.

6. Upwelling velocity Upwelling velocity will have directly output from model. Only need one more interpolation to a particular depth.