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Storing, Finding and Accessing Earth System Modeling Data: Insights and Challenges from WarmWorld-Easier
No full textImprovements in computational speed lead to better resolutions in Earth System Models (ESM) allowing them to resolve scales of a few kilometers. The volume of the resulting data greatly increases with the improvements in resolution and introduces a challenge to processing and storing these results. While modern HPC systems provide petabyte-scale capacity for file storage, analyzing such data on local user systems can become a prohibitive bottleneck. Beyond the sheer demands on processing high-volume ESM data, there is also increasing demand to make them FAIR and in particular findable. The goal of the “Easier” module of the Warmworld project aims to simplify the access to ESM data from different HPC centers, in particular the German Climate Computing Center (DKRZ) and the Jülich Supercomputing Centre (JSC). One aspect is the creation of a joint catalog following the SpatioTemporal Asset Catalogs (STAC) specification. This enhances the findability for data available at both centers. The accessibility is provided by links in the catalog to access the data, either directly on disk, as a download or, as a mid term goal, through streaming of data on demand with zarr over http. The explicit implementation of the required REST-APIs depends on the infrastructure, hardware and software, of the data centers as well as the organization of the stored data. As the first data backend at JSC, we set up a Fields DataBase (FDB), developed by European Centre for Medium-Range Weather Forecasts (ECMWF), to store the ESM results as multi-dimensional data cubes. For data retrieval, we provide a download service. Data are identified within the FDB by their metadata according to the Meteorological Archival and Retrieval System (MARS), developed by ECMWF. The automated access to HPC system is achived with the UNiform Interface to COmputing REsources (UNICORE). The download service integrates HelmholtzID, the Helmholtz authentication and authorization infrastructure. This will allow a large number of institutions to access these services with the possibility to control access and resource use. ƒOur poster will illustrate the combination of these various tools and services for creating the envisoned services for the infrastructure at JSC as well as our federated STAC catalog. We wish to close our presentation with an overview on further challenges related to ESM data addressing aspects of data management and data access
AirFloX: Bridging Scales for SIF Calibration and Validation in Support of FLEX
No full textThe upcoming FLuorescence EXplorer (FLEX) mission of the European Space Agency (ESA) will provide global, high-resolution maps of sun-induced chlorophyll fluorescence (SIF), enhancing the monitoring of photosynthetic activity. Accurate calibration and validation (Cal/Val) of FLEX products through independent in-situ measurements is essential to ensure reliable SIF estimates. While tower-based systems offer unattended, continuous measurements, they are not suitable for spatially heterogeneous landscapes. Airborne systems offer broad spatial coverage and capture spatial heterogeneity, but they are costly and have limited temporal resolution. Unmanned aerial systems (UAS) are a lower-cost alternative, with the potential to bridge the spatial and temporal gap between ground-based and satellite observations. In this context, we present AirFloX: a novel, modular, spectroscopy system deployable on UAS or helicopters capable of measuring SIF and high-resolution reflectance. AirFloX is a non-imaging spectroscopy system consisting of two point spectrometers (Ocean Insight, USA) connected to bifurcated fibre optics switching between the downwelling irradiance and upwelling radiance. The two spectrometers complement each other having different spectral range and resolution for measuring both SIF and reflectance. The 4 kg payload can be mounted on commercial UAS platforms, and a dedicated graphical user interface allows to customize the acquisition. AirFloX was extensively tested during two ESA-funded field campaigns in May and June 2025 in agricultural and forested areas in Tuscany, Italy. The campaigns aimed to evaluate different strategies for the validation of the SIF products of the upcoming FLEX mission. To this end, we implemented sampling schemes based on optimisation methods designed to find the optimal locations of the sampling points maximising their spatial representativeness. Multi-scale SIF measurements were collected using ground-based systems (FloX) and airborne systems (AirFloX) mounted on two UAS and a helicopter (HELiPOD system), enabling to cross-compare the results at different scales. In this contribution we present the first results of these campaigns, discuss associated challenges, and outline implications for the Cal/Val of SIF satellite products
Comparison of single and combined salt and cold stress effects and their challenges for hyperspectral measurements of different Capsicum species
No full textGiant orbital Zeeman effects in a magnetic topological van der Waals interphase
No full textVan der Waals (vdW) heterostructures allow the engineering of electronic and magnetic properties by the stacking different two-dimensional vdW materials. For example, orbital hybridisation and charge transfer at a vdW interface may result in electric fields across the interface that give rise to Rashba spin-orbit coupling. In magnetic vdW heterostructures, this in turn can drive the Dzyaloshinskii-Moriya interaction which leads to a canting of local magnetic moments at the vdW interface and may thus stabilise novel 2D magnetic phases. While such emergent magnetic 'interphases' offer a promising platform for spin-based electronics, direct spectroscopic evidence for them is still lacking. Here, we report Zeeman effects with Landé -factors up to at the interface of graphene and the vdW ferromagnet FeGeTe. They arise from a magnetic interphase in which local-moment canting and itinerant orbital moments generated by the non-trivial band topology of FeGeTe conspire to cause a giant asymmetric level splitting when a magnetic field is applied. Exploiting the inelastic phonon gap of graphene, we can directly access the buried vdW interface to the FeGeTe by scanning tunnelling spectroscopy. Systematically analyzing the Faraday-like screening of the tip electric field by the graphene, we demonstrate the tunability of the constitutional interface dipole, as well as the Zeeman effect, by tip gating. Our findings are supported by density functional theory and electrostatic modelling
Enabling full localization of qubits and gates with a multi-mode coupler
No full textTunable couplers are a key building block of superconducting quantum processors, enabling high on-off ratios for two-qubit entangling interactions. While crosstalk can be mitigated in idle mode, conventional single-mode couplers lack independent control over interactions in the one- and two-excitation manifolds, leading to unitary errors such as leakage during gate operations. Moreover, even at the nominal decoupled point, residual wavefunction delocalization persists, causing unintended qubit-qubit coupling. Here we propose a multi-mode tunable coupler that enables nonlinear control of interactions across excitation manifolds, achieving a high on-off ratio in the one-excitation manifold while suppressing coupling in the two-excitation manifold. The proposed design also realizes complete localization between qubits, providing perfect isolation at the decoupled point and opening new possibilities for scalable, high-fidelity quantum gates
