- Particle-based-cloud-modelling

Scientific Programmer role at MPI-M: ICON+Cleo super droplets
by Sylwester Arabas 01 Sep '26

01 Sep '26

https://jobs.mpimet.mpg.de/jobposting/72be010753c41cc0615eee73abe68c4d1da9f… Contact: clara.bayley(a)mpimet.mpg.de, daniel.klocke(a)mpimet.mpg.de Deadline: September 15, 2026 The MPI-M is seeking to appoint a Scientific Programmer (W-0066 | all genders) for a fixed term of three years in the Scientific Computing Laboratory. The successful applicant will become a member of the scientific computing group, led by Dr. Daniel Klocke, and with co-supervision by Dr. Clara Bayley. RESPONSIBILITIES: - Contribute to enabling large-scale ICON simulations coupled with the super-droplet model Cleo for cloud microphysics - Generalise Cleo and its coupling to ICON for a broader range of particle-based use-cases - Collaborate with European partners in the EU funded Lighthouse Code project, PHOENIX (Performance and Heterogeneous Optimised Earth-system modeling with Next-generation ICON eXecution) - Support the model evaluation and development of ICON and Cleo PROFILE: - A degree in computer science, software engineering, physics, or related fields - Excellent programming skills, evidence of collaborative coding and ideally experience with C++ and Kokkos - Experience in high-performance computing - The ability to work independently as well as collaboratively - Interest in working with particle methods and km-scale climate models - Proficiency in English, German language skills are welcome but not required ... -> https://jobs.mpimet.mpg.de/jobposting/72be010753c41cc0615eee73abe68c4d1da9f…

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Fwd: Two postdoc positions on particle-based cloud modeling at Univ of Hyogo (Moonshot and UAEREP)
by Sylwester Arabas 09 Oct '25

09 Oct '25

-------- Forwarded Message -------- Subject: Two postdoc positions on particle-based cloud modeling at Univ of Hyogo (Moonshot and UAEREP) Date: Wed, 8 Oct 2025 16:36:45 +0900 From: Shin-ichiro Shima <s_shima(a)gsis.u-hyogo.ac.jp> Dear colleagues, Univ of Hyogo (Kobe, Japan) is hiring two project researchers on particle-based cloud modeling: - Moonshot Goal 8 (1.25-6.25 years) https://s-shima-lab.sakura.ne.jp/jobs/postdoc-250527 - UAEREP (2 years) https://s-shima-lab.sakura.ne.jp/jobs/postdoc-250725 The application deadline is October 28th 2025 I am sorry for the short notice, but I would really appreciate it if you could forward these opportunities to anyone who might be interested. Thank you! Best regards, Shin-ichiro -- ---------------------------------------------------------- Shin-ichiro Shima/島伸一郎 (Professor) Graduate School of Information Science, University of Hyogo, Kobe, Japan. Web: https://s-shima-lab.sakura.ne.jp Tel,FAX: 078-303-1995 E-mail : s_shima(at.mark)gsis.u-hyogo.ac.jp ----------------------------------------------------------

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Fwd: Ph.D. Position in Cloud Physics at the Free University of Berlin, Germany
by Sylwester Arabas 29 Jul '25

29 Jul '25

-------- Forwarded Message -------- Date: Fri, 25 Jul 2025 21:45:30 +0200 From: "Hoffmann, Fabian" <f.hoffmann(a)fu-berlin.de> Subject: Ph.D. Position in Cloud Physics at the Free University of Berlin, Germany Hello Everyone, We seek a motivated research assistant (Ph.D. student) to support our ongoing research on mixed-phase clouds in our newly established group at the Free University of Berlin, Germany. Particularly, we would like to address mixed-phase processes in deep convective clouds to understand how these clouds interact with aerosol. Accordingly, certain aspects of our group's Lagrangian cloud microphysical model require further development or adaptation. Within this general setting, the research assistant has the opportunity to address their own topics. Beyond research, the research assistant is expected to support teaching at the Institute of Meteorology (e.g., by teaching exercises and tutorials, and supervising Bachelor?s and Master's students). For more information, please check the official announcement: https://www.fu-berlin.de/universitaet/beruf-karriere/jobs/english/GW-WiMi-_… Best, Fabian Hoffmann ------------------------------------------ Dr. Fabian Hoffmann Free University of Berlin Institute of Meteorology Carl-Heinrich-Becker-Weg 6-10 12165 Berlin, Germany ------------------------------------------

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super-droplets and beyond AMS session in Houston, Jan 2026
by Sylwester Arabas 30 Jun '25

30 Jun '25

Dear Aerosol & Cloud Modellers, We are pleased to announce the call for abstracts for an AMS Annual Meeting session on **Advances in numerical modeling of aerosol-cloud interactions: moment-, bin- and particle-resolved methods and beyond**. The session is organised jointly between the 18th Symposium on Aerosol Cloud Climate Interactions, the Third Symposium on Cloud Physics and the Fifth Symposium of Community Modeling and Innovation. Please mark in your calendars: - abstract submission deadline: 14 Aug 2025 - meeting in Houston: 25-29 Jan 2026 Session description is provided at: https://ams.confex.com/ams/106ANNUAL/meetingapp.cgi/Session/72794 Abstract submission system is open at: https://ams.confex.com/ams/106ANNUAL/cfp.cgi Looking forward to meeting you in Houston or online (hybrid format). Please forward this message to your collaborators and networks. Sylwester Arabas @agh.edu.pl Emily de Jong @llnl.gov Nicole Riemer @illinois.edu Lin Lin @llnl.gov Adele Igel @ucdavis.edu P.S. we're using the particle-based-cloud-modelling(a)mail.agh.edu.pl mailing list for relevant announcements, to subscribe (if not already subscribed), visit: https://particle-based-cloud-modelling.github.io/ -- Environmental Physics Group, AGH University of Kraków, Poland sylwester.arabas(a)agh.edu.pl | +48502254779 | https://zfs.agh.edu.pl/

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Fwd: Postdoc position at Notre Dame in air-sea interaction and droplet microphysics
by Sylwester Arabas 21 May '25

21 May '25

-------- Forwarded Message -------- Subject: Postdoc position at Notre Dame in air-sea interaction and droplet microphysics Date: Tue, 20 May 2025 20:44:41 -0400 From: David Richter <David.Richter.26(a)nd.edu> Dear colleagues, I am hiring a postdoctoral researcher at the broad intersection of air-sea interaction, wave-induced turbulence, and spray/marine aerosol/cloud microphysics. The specific goals and scientific questions will depend on the expertise of the candidate, but the idea is to use LES and Lagrangian droplet modeling to investigate process-level questions in the areas of fluxes, droplet-turbulence interaction, and wave influences on surface layer turbulence and droplet/aerosol transport. I have attached an advertisement here, and I would greatly appreciate it if you could forward this to or recommend anyone you know who might be eligible and interested. Many thanks, -- David Richter Professor Department of Civil and Environmental Engineering and Earth Sciences University of Notre Dame 120A Cushing Hall Office: 574-631-4839 Email: David.Richter.26(a)nd.edu <mailto:David.Richter.26@nd.edu> Website: http://nd.edu/~drichte2 <http://nd.edu/~drichte2>

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Axel Seifert's webinar on May 21-st 4 pm CET (@uni-mainz.de)
by Sylwester Arabas 19 May '25

19 May '25

-------- Forwarded Message -------- Subject: [EXT] Seminar mathematics and atmospheric physics on May 21 Date: Mon, 19 May 2025 09:17:06 +0200 From: Peter Spichtinger <spichtin(a)uni-mainz.de> Dear all, this is a kind reminder for the next talk in our monthly seminar on mathematics and atmospheric physics. On Wednesday, May 21, Axel Seifert (German Weather Service) will talk about Ice microphysics in higher dimensions: super-particles and the geometry of snowflakes Abstract: Understanding snowflake formation requires modeling the interplay between complex microphysical processes and environmental conditions. In this talk, I will present ice microphysics in a higher-dimensional phase space using a stochastic super-particle approach, where each numerical particle represents an ensemble of real ice crystals. Building on the McSnow modeling framework—which includes detailed habit prediction for ice particles—we extend the representation of snowflake geometry to more realistically capture particle growth and aggregation. In the first part of the talk, I introduce an ML-based coarse-graining method that enables the derivation of a multi-moment, P3-like bulk microphysics scheme directly from super-particle simulations—providing a systematic link between Lagrangian and Eulerian modeling frameworks. In the second part, the focus shifts to the variability in the geometry of aggregate snowflakes. We show that the maximum dimension of aggregates — given fixed mass and monomer count — follows a lognormal distribution, revealing the stochastic nature of the aggregation process. This rigorous treatment offers new insights into the morphological diversity of snowflakes and contributes to improved representations of ice particles in weather and climate models. And even if it doesn’t make the forecasts any better—or solve the problem of climate change—we gain a deeper understanding of clouds, and have some fun doing applied math along the way. The seminar will start at 16:00 local time (i.e. 14 UTC). The zoom link is provided below (starting already at 15:45 local time). The next dates for the seminar are as follows June 4 Jana de Wiljes, TU Ilmenau Please also check the homepage of the seminar: https://www.staff.uni-mainz.de/spichtin/seminar.html Best, Peter PS: Please feel free to distribute the announcement to others Reminder: The registration and abstract submission for the SCALES conference https://model.uni-mainz.de/scales-conference-2025/ are still open ... ----------------------- Peter Spichtinger is inviting you to a scheduled Zoom meeting. Topic: Seminar Mathematics and Atmospheric Physics Time: May 21, 2025 03:45 PM Amsterdam, Berlin, Rome, Stockholm, Vienna Join Zoom Meeting https://uni-mainz-de.zoom.us/j/68522641413?pwd=SX2azpaqe4yBP0Cy907rvhVk27Ky… Meeting ID: 685 2264 1413 Passcode: 293629 --- One tap mobile +496950500952,,68522641413#,,,,*293629# Germany -- ---------------------------------------------------------------- Prof. Dr. Peter Spichtinger Theoretical cloud physics Institute for Atmospheric Physics (IPA) Johannes Gutenberg University Mainz J.-J.-Becherweg 21, 55128 Mainz, Germany Office: 05-163 Phone: +49 (0) 6131 39 - 23157 Fax: +49 (0) 6131 39 - 23532 email:spichtin@uni-mainz.de https://www.staff.uni-mainz.de/spichtin/ https://theoryofclouds.ipa.uni-mainz.de/ https://binary.uni-mainz.de/ https://model.uni-mainz.de/ ----------------------------------------------------------------

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Fwd: [IGF] webinar 2025-05-16 13:15 CET ... online via Zoom (Emma Ware)
by Sylwester Arabas 14 May '25

14 May '25

Univ. Warsaw webinar by Emma Ware (UCDavis & agh.edu.pl) Fri May 16 at 1:15 pm CET (8:15 pm in Japan, 7:15 am East Coast) title: Adaptive Time-Stepping within the Super-Droplet Method Monte-Carlo Coagulation Scheme zoom link: https://uw-edu-pl.zoom.us/j/92869816385?pwd=OGGyBBxKufiLUNw1jbRmriWoWGKYQE.1 (Meeting ID: 928 6981 6385 Passcode: 447840) -------- Forwarded Message -------- Subject: [IGF] Seminarium, 2025-05-16 13:15, [...] and online via Zoom Date: Wed, 14 May 2025 08:00:06 -0000 To: zfa_seminarium(a)fuw.edu.pl *Adaptive Time-Stepping within the Super-Droplet Method Monte-Carlo Coagulation Scheme* https://www.igf.fuw.edu.pl/pl/seminars/presentation/adaptive-time-stepping-… Emma Ware Akademia Górniczo-Hutnicza We are presenting an analysis on an adaptive time-stepping scheme for the Super-Droplet Method (SDM) introduced in prior work to improve the efficiency and accuracy of probabilistic droplet coalescence in cloud microphysics. Superdroplets are computational particles that represent weighted ensembles of real cloud droplets, enabling high-fidelity representations of microphysical processes like collision–coalescence. SDM, first introduced by Shima et al. (2009), is a Monte Carlo algorithm that selects superdroplet pairs linearly within each timestep and simulation volume to test for collisions. The algorithm also includes logic that allows multiple collisions between the same candidate pair, accounting for the likelihood of repeated interactions within a single timestep. Adaptive time-stepping dynamically adjusts simulation time steps to control the coalescence deficit: a quantifiable error that arises when the available droplet population within superdroplet candidate pairs is not large enough to undergo the expected collision events. While SDM exhibits inherent statistical spread due to its probabilistic nature, the deficit represents a systemic underestimation bias of collision events. To validate the adaptive scheme, we implement it independently in two open-source models, PySDM and Droplets.jl. The results demonstrate consistency across platforms. Using the classical Golovin test case, we compare SDM and adaptive SDM scheme in terms of convergence, computational cost, and fidelity. We also draw conceptual parallels to the Weighted Flow Algorithm (WFA) Monte Carlo algorithm employed in PyPartMC, which employs analogous adaptive logic for eliminating the deficit within a different coalescence framework. Our convergence analysis spans a range of timesteps, superdroplet counts, and initialization methods, examining how the deficit scales and exploring the trade-off between efficiency and error mitigation when adaptive time-stepping is implemented. We show that the substepping procedure maintains a computational cost similar to that of the original SDM using the “parent” timestep, while achieving accuracy comparable to smaller fixed timesteps. Overall, our results demonstrate that adaptive time stepping provides a more efficient path to reducing coalescence error than uniformly decreasing the timestep, with implications for large-scale cloud and precipitation modeling. While we focus on warm-phase microphysics, the results are also applicable to cold and mixed-phase systems, as well as other coagulation problems outside atmospheric science. Join Zoom Meeting https://uw-edu-pl.zoom.us/j/92869816385?pwd=OGGyBBxKufiLUNw1jbRmriWoWGKYQE.1 <https://www.google.com/url?q=https://uw-edu-pl.zoom.us/j/92869816385?pwd%3D…> Meeting ID: 928 6981 6385 Passcode: 447840 /Koordynator seminarium: / /prof. dr hab. Hanna Pawłowska/ /e-mail: hanna.pawlowska(a)igf.fuw.edu.pl/ /telefon: +48 22 55 32 035/ Wysłano dnia: 14-05-2025 10:00 (c) 2025 UW, WF, Instytut Geofizyki, www.igf.fuw.edu.pl /This email has been sent automatically, please do not reply./ /If you see an error or if you are not the correct recipient, please contact: sekretariat.IGF(a)fuw.edu.pl/

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NCAR webinar on Mar 20th (2 pm MDT, 9 pm CET): S-I Shima: "20th anniversary of the super-droplet method"
by Sylwester Arabas 12 Mar '25

12 Mar '25

https://www.mmm.ucar.edu/events/seminar/2025/dr-shin-ichiro-shima-133397 title: "20th anniversary of the super-droplet method" speaker: Dr. Shin-ichiro Shima, University of Hyogo, Kobe, Japan Mar. 20, 2025, 2:00 pm MDT (9 pm CET) This seminar will be hybrid, you may attend in-person or watch the live webcast: https://sundog.ucar.edu/public/page/MMM Participants watching the live webcast may ask questions during the seminar via Slido. Abstract (https://www.mmm.ucar.edu/sites/default/files/2025-03/Shin-ichiro%20Shima_Ma…) The super-droplet method (SDM) is a Lagrangian particle-based numerical algorithm designed to model cloud microphysics and its coupling with cloud dynamics. It was 2005 when I joined Dr. Kanya Kusano’s group at the Earth Simulator Center, JAMSTEC, Japan. With an eye on the future of supercomputers, we worked on creating novel numerical algorithms for multiscale-multiphysics phenomena. SDM was one of the significant outcomes of our efforts. In Shima et al. (2009), we discussed the general framework of SDM and key algorithms required for its numerical implementation. Instead of applying Eulerian mixing ratios for various predefined cloud condensate and precipitation categories (cloud water, rain, cloud ice, snow, graupel, hail), SDM applies point particles, referred to as super-droplets or super-particles, to represent the enormous number of aerosol, cloud, and precipitation particles present inside the simulated domain of a cloud model. The super-particles are traced in physical space using the model-predicted flow field, and they grow or shrink as they move with the flow. The treatment of particle collision-coalescence was challenging, so we constructed an efficient Monte Carlo algorithm to address it. In SDM, the fundamental process rate equations are directly solved, allowing us to seamlessly simulate various cloud related phenomena from the aerosol scale to convective scale. SDM offers significant advantages over Eulerian approaches typically used in cloud models, but it took a long time for the idea to gain acceptance within the atmospheric science community. Today, Lagrangian particle-based cloud models are being used widely for various applications, and SDM has become synonymous with them. In this talk, I will present an overview of recent advances and applications of the Lagrangian particle-based cloud models. Those include applications to warm-rain development studies, inclusion of habit prediction and proper representation of various ice growth mechanisms, and refinement of the numerical algorithms. -- Environmental Physics Group, AGH University of Kraków, Poland sylwester.arabas(a)agh.edu.pl | +48502254779 | https://zfs.agh.edu.pl/

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Summer School "Complex Particles in Complex Flows with Environmental Applications" in La londe les Maures, France, June 15-20 2025
by Sylwester Arabas 12 Feb '25

12 Feb '25

https://sites.google.com/view/copartcoflow/copartcoflow Toipic: Complex particle transport in complex flows with environmental applications Location: La londe les Maures, France - June 15th-20th 2025 Application deadline: February 28th, 2025 Objectives: This summer school aims to gather a combination of junior and senior scientists with research interests in the fate and transport of complex particles in complex flows with diverse applications such as plastics pollution in the natural environment. Lecturers: - Enrico Calzavarini, Université de Lille - Michelle DiBenedetto, University of Washington - Giuseppe Suaria, CNR-ISMAR - Jean-Luc Thiffeault, University of Wisconsin-Madison - Erik van Sebille, Utrecht University ... The registration fee will not exceed 600€ (without tax) with the final price to be communicated after the application deadline. The registration fee includes the housing and all meals, but not travel to the venue.

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hybrid course in Udine, Sep 8-12: "Lagrangian Approaches to Multiphysics Two-phase Flows"
by Sylwester Arabas 12 Feb '25

12 Feb '25

https://cism.it/en/activities/courses/C2512/ ... The course will focus on Lagrangian approaches. They are often methods of choice to treat the particulate phase transport and polydispersity; they may also be used, in terms of so-called particle-based methods, for the macroscopic description of fluid motion. Looked at from this perspective, the course should nicely complement a typical curriculum on fluid dynamics and CFD modelling to provide a broader view, next-to (but not off) the beaten track, especially valuable for PhD candidates. ... ... Invited lectures: - Mickael Bourgoin (Ecole Normale de Lyon, France) - Jochen Froehlich (TU Dresden, Germany) - Alessandra S. Lanotte (CNR Institute of Nanotechnology, Lecce, Italy) - Alex Liberzon (Tel Aviv University, Israel) - Jacek Pozorski (IMP, PAN, Gdansk, Poland) - Alfredo Soldati (Vienna University of Technology, Austria) ... The course is offered in a hybrid format, allowing participants the flexibility to attend either in person or remotely via the Microsoft Teams platform. ... Registration fees: - Early Bird On-Site Participation: €650.00+VAT* Deadline: July 8, 2025 - Late On-Site Participation: €800.00+VAT* Deadline: August 26, 2025 - Live Streaming Online Participation: €250.00+VAT* Deadline: August 26, 2025 -- Environmental Physics Group, AGH University of Kraków, Poland sylwester.arabas(a)agh.edu.pl | +48502254779 | https://zfs.agh.edu.pl/

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