9:40

Tropical-to-Polar Teleconnections: Does E3SM produce verifiable teleconnections in ice sheet and sea ice mass balance, or our best representation of them, in both hemispheres?

Carolyn Begeman Shixuan Zhang

10 min intro + 10 min discussion

• Present SORRM teleconnections analysis and discussion questions

• Angles to explore:

  • Impact of regional refinement on teleconnection representation

  • Connection with ozone changes

• Teleconnections to explore:

  • IPO and connection with atmospheric rivers

    • Renu brought up ARPA project on atmospheric rivers that we could connect with to see how they relate to Arctic teleconnections

    • CMIP models generally do not represent IPO phase well. E3SM may have an advantage there

  • Arctic polar vortex, stratospheric conditions impact on the jet stream

    • Wieslaw suggested working with HiLAT RASM folks (Hilong Wang). Possibility of attending the HiLAT Phase 3 meeting in September (contact Wieslaw if interested)

    • Connect with wildfire researchers on the E3SM team that are looking at the relationship with Arctic sea ice

• Ensemble design:

  • Some modes of variability may require 100s of ensemble members to characterize (e.g., 200 ensemble members for some Arctic teleconnections)

  • However, the number of ensemble members needed is in relation to our particular configuration’s signal to noise ratio. Thus, the prior estimates may not be a good indication for E3SM. Contact Wieslaw for more details about his work in prep.

• Other considerations:

  • v3 appears to have higher fidelity tropical modes of variability but v2 appears to have better tropical to South Polar teleconnections

  • Renu also indicated that there will be more teleconnections-related projects down the line but they are not funded yet

10:00

Exclusion Experiments: Can we devise a series of physics exclusion experiments to help pinpoint relevant problems to polar bias and skill?

Exclusion experiments test the response of the system to changes in inputs. Examples include:

A. Starting from a spun up state, and then: 1) turning off all fluxes  in individual components (flywheel isolation),  2) turning off the sun (system spin down),   3) turning off individual incoming fluxes for the ocean, sea ice, land etc (component spin down).

B. Starting from rest: 1) Running the whole model without solar input (system stay-at-rest), 2) Running with all component fluxes turned off (component stay-at-rest type 1), 3) Running individual components with no flux input (component stay-at-rest type 2).

Andrew Roberts Wuyin Lin

10 min intro + 10 min discussion

10:20

Infrastructure Needs: What infrastructure improvements, including changes to model output, coupled testing, are needed to help reach our science objectives?

Alice Barthel Xylar Asay-Davis

10 min intro + 10 min discussion

• On polar campaign needs from Omega:

  • Xylar: we may need GM in polar regions even at ~2-5 km resolution Omega

  • Luke: we do plan to add GM and other eddy parameterizations in 2026

  • There is a need for more conversation between polar group and Omega to ensure effective transition from MPAS-Ocean

• On model output needs:

  • Luke: don’t cut polar output too much because the “light“ I/O configuration may become standard

  • Elizabeth: we don’t need more sea ice output, just more sea ice analysis in MPAS-Analysis

  • Andrew: consider high-frequency output to understand model behavior better

• On testing:

  • The polar group’s needs should be better represented in E3SM ocean developer’s test suite