ICON Meeting 2022/2

24 May 2022, ETH Zurich (L 17.1) and via Zoom

Participants

Michael Jähn (MJ), Jonas Jucker (JJ), Annika Lauber (AL), Michael Steiner (MS), Lionel Constantin (LC), Guillaume Bertoli (GB), Stefan Rüdisühli (SR), Stephanie Westerhuis (SW), Brigitta Goger (BG), Nadja Omanovic (NO), Jacopo Canton (JC), Tamara Bandikova (TB), Christina Schnadt Poberaj (CSP), William Sawyer (WS), Andrea Stenke (AS), Sylvaine Ferrachat (SF), Kseniya Ivanova (KI), Anurag Dipankar (AD), Stephan Henne (SH)

Minutes by Annika Lauber

Reports

C2SM (Michael Jähn, Jonas Jucker, Annika Lauber, Tamara Bandikova)

MJ welcomes all participants to the meeting and presents C2SM ICON news together with JJ, AL and TB.

Short presentations from participants

MS from EMPA implemented online emission, online flux ensemble, etc. in ART. A view things have been merged. Has memory allocation problems with boundary conditions that are time-dependent. Occurs for more than 83 time-dependent boundary fields.

LC from EMPA is working on integrating ICON-ART into a framework called CIF (Community Inversion Framework).

SR shows slides about work in Sebastian Schemm’s group . A paper on an aquaplanet study was recently published . A second accepted paper deals with an aquaplanet with high-resolution nests over NH SST front. They have an ongoing project using ML (Machine Learning) on ecRad. The group will ask C2SM/EXCLAIM community for help in coupling python ML tools to Fortran.

GB works on ML emulation on ecRad.

SW informs that MeteoSwiss is currently facing severe problems with ICON not running fast on new machines (seven times slower). MeteoSwiss wants to run ICON operationally next year. SW shows slides about her current work on transparent stratus clouds in ICON . Observations - model comparison shows that ICON is not predicting thick stratus clouds. The predicted clouds mainly cover 60-80% but never 100% as in reality. This has a negative impact on correct radiation prediction with a bias of 100 W/m2. SW tries to motivate Martin to work on this. SW is in contact with Israeli colleagues who have introduced a nonphysical ad-hoc parameter to improve cloud cover in the Mediterranean to deal with this issue. CS asks how often this phenomenon occurs. SW says that is a reoccurring problem but so far the comparison was done for only one case but she is working on a second case.

BG is a new postdoc in EXCLAIM and attends her first ICON user meeting. Her focus will be ICONs turbulence parameterization. SH asks if BG is aware that EMPA, MeteoSwiss, University of Frankfurt currently have a project on that. BG says that she is aware of that.

NO is working with the 2-moment microphysics scheme. There are new updates like the saturation adjustment before calling the microphysics. NO is doing the cloud simulations for the CLOUDLAB project.

JC is working for EXCLAIM now. He is working on parameterizations with grid sizes below 1km.

WS is waiting for ICON-2.6.5., which is the basis for EXCLAIM and should be released within the next few weeks. There is currently a huge clean-up of the ECHAM physics going on, which will be replaced by the AES physics. There is a mass of delays in porting ICON to the LUMI supercomputer. Only the cray compiler is working with AMD-GPUs but is facing issues.

AS is working with ICON-ART on Euler to simulate trace elements. Mainly technical work is going on right now.

SF is doing ICON-HAM global simulations. Elsa Germann solved most bugs in the GPU port of HAM.

SH from EMPA is working on the ICON-ART porting to GPU. Next to that SH is working with the FLEXPART version for ICON. They convert ICON output to COSMO grid. First tests comparing the output give reasonable results. Nothing concrete.

KI from EMPA is working on decoupling FLEXPART in ICON.