Levante supercomputer at the German Climate Computing Center (Credit: DKRZ)
SUBTOPIC

Long-term Projections

Running the climate system forward a century at a time, without the model drifting off course.

Image: DKRZ

Stability Over Speed

A century-scale climate projection is not simply a longer weather forecast — it is a fundamentally different computational problem. Where NWP optimizes for wall-clock turnaround, ESM optimizes for bit-for-bit numerical stability across billions of timesteps, ensuring that small floating-point errors never accumulate into a spurious climate trend. Malgukke architectures pair CPU-dense nodes for the coupled ocean-atmosphere-ice solvers with a storage fabric built to hold the resulting archive for decades.

HPC Solution Architecture: Model Spin-up to Century Archive

A coupled Earth System Model pipeline, as run on DKRZ's Levante for the ICON model:

Spin-up Pre-industrial equilibrium state Coupled Core (ICON) CPU Nodes Atmosphere-Ocean-Ice GPU Nodes Km-scale downscaling Drift Check Conservation of energy & mass CMIP Ensemble Scenario runs, multi-model harmony Century Archive Tiered storage, decades of access Archived runs seed the next generation's spin-up state

Running on the TOP500: Levante

TOP500 — NOVEMBER 2025 LIST

Levante — German Climate Computing Center (DKRZ), Hamburg

Levante is ranked No. 164 on the November 2025 TOP500 list and is the dedicated Earth system research machine for Germany's climate community. Built on Atos BullSequana XH2000 technology with roughly 390,000 processor cores, Levante is the only European system that has run the fully coupled, GPU-accelerated ICON Earth system model at a global 1.2 km resolution — the resolution needed to represent convective clouds directly rather than through parameterization.

Yes — this is a real, currently operating TOP500-ranked system, directly used by MPI-M and DKRZ for the ICON simulations described on this page.

#164
Global TOP500 Rank
390K+
Processor Cores

Voices from the Field

Researchers using Levante and Earth system models for century-scale projections:

Jochem Marotzke

Director, Max Planck Institute for Meteorology

On simulating the global climate system at 1 km resolution for the first time — made possible only by Levante.

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Daniela Matei

Senior Research Scientist, Max Planck Institute for Meteorology

On decadal-to-interannual climate predictability and the role of ocean circulation in shaping long-term projections.

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