# Building high-resolution transport matrices from ACCESS-OM2 outputs **URL:** \ **Category:** Ocean\ **Created:** [24 October 2025 03:20 UTC](https://forum.access-hive.org.au/t/building-high-resolution-transport-matrices-from-access-om2-outputs/5431 "2025-10-24T03:20:44Z")\ **Posts on this page:** 1\ **Showing post:** 9
**Author:** ![Benoit](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.access-hive.org.au/benoit/32/3115_2.png) [@Benoit](https://forum.access-hive.org.au/u/Benoit)\ **Post date:** [20 November 2025 23:58 UTC](https://forum.access-hive.org.au/t/building-high-resolution-transport-matrices-from-access-om2-outputs/5431/9 "2025-11-20T23:58:24Z")
#### Did something change between cycles 3 and 4 for the OM2-01 IAF runs? I noticed a substantial “jump” in the deep circulation between `01deg_jra55v140_iaf_cycle3` and `01deg_jra55v140_iaf_cycle4` and I’d like to understand what drove this jump. If you look at the MOC streamfunctions averaged over each cycle, you can see that the bottom cell extends much further to the north in cycle 4 (4th panel in image below): ![image](https://us1.discourse-cdn.com/flex020/uploads/access1/original/2X/4/47451fb9039a5778982dd020d0ca50cf09af7c75.jpeg) Comparing the time series of AABW transport at 40°S (taken as minus the minimum of the streamfunction at 40°S below 1036 kg m⁻³; top panel in image below) shows some change between cycles but nothing suspicious. However, at 20°N (bottom panel), the difference is striking: ![image](https://us1.discourse-cdn.com/flex020/uploads/access1/original/2X/2/2c201cd8e19330c48ef3c5f17c9b672288514200.jpeg) Could this is related to the reproducibility issues / bugs about these runs discussed [on the Hive](https://forum.access-hive.org.au/t/inconsistent-ocean-and-sea-ice-in-final-7-5yr-of-0-1-iaf-cycle-4/1492/1) and [on GitHub](https://github.com/COSIMA/access-om2/issues/266)? cc @aekiss @LaurieM --- _[View the full topic](https://forum.access-hive.org.au/t/building-high-resolution-transport-matrices-from-access-om2-outputs/5431)._