Universal differential equations for glacier ice flow modelling Geoscientific Model Development DOI 10.5194/gmd-16-6671-2023 15 November 2023 We developed a new modelling framework combining numerical methods with machine learning. Using this approach, we focused on understanding how ice moves within glaciers, and we successfully learnt a prescribed law describing ice movement for 17 glaciers worldwide as a proof of concept. Our framework has the potential to discover important laws governing glacier processes, aiding our understanding of glacier physics and their contribution to water resources and sea-level rise. Read more
Machine learning for numerical weather and climate modelling: a review Geoscientific Model Development DOI 10.5194/gmd-16-6433-2023 13 November 2023 Machine learning (ML) is an increasingly popular tool in the field of weather and climate modelling. While ML has been used in this space for a long time, it is only recently that ML approaches have become competitive with more traditional methods. In this review, we have summarized the use of ML in weather and climate modelling over time; provided an overview of key ML concepts, methodologies, and terms; and suggested promising avenues for further research. Read more
Emulating lateral gravity wave propagation in a global chemistry–climate model (EMAC v2.55.2) through horizontal flux redistribution Geoscientific Model Development DOI 10.5194/gmd-16-5561-2023 27 September 2023 The columnar approach of gravity wave (GW) schemes results in dynamical model biases, but parallel decomposition makes horizontal GW propagation computationally unfeasible. In the global model EMAC, we approximate it by GW redistribution at one altitude using tailor-made redistribution maps generated with a ray tracer. More spread-out GW drag helps reconcile the model with observations and close the 60°S GW gap. Polar vortex dynamics are improved, enhancing climate model credibility. EMAC v2.55.2) through horizontal flux redistribution">Read more
The three-dimensional structure of fronts in mid-latitude weather systems in numerical weather prediction models Geoscientific Model Development DOI 10.5194/gmd-16-4427-2023 7 August 2023 We investigate the benefit of objective 3-D front detection with modern interactive visual analysis techniques for case studies of extra-tropical cyclones and comparisons of frontal structures between different numerical weather prediction models. The 3-D frontal structures show agreement with 2-D fronts from surface analysis charts and augment them in the vertical dimension. We see great potential for more complex studies of atmospheric dynamics and for operational weather forecasting. Read more
DSCIM-Coastal v1.1: an open-source modeling platform for global impacts of sea level rise Geoscientific Model Development DOI 10.5194/gmd-16-4331-2023 4 August 2023 This work presents a novel open-source modelling platform for evaluating future sea level rise (SLR) impacts. Using nearly 10 000 discrete coastline segments around the world, we estimate 21st-century costs for 230 SLR and socioeconomic scenarios. We find that annual end-of-century costs range from USD 100 billion under a 2 °C warming scenario with proactive adaptation to 7 trillion under a 4 °C warming scenario with minimal adaptation, illustrating the cost-effectiveness of coastal adaptation. DSCIM-Coastal v1.1: an open-source modeling platform for global impacts of sea level rise">Read more
Pace v0.2: a Python-based performance-portable atmospheric model Geoscientific Model Development DOI 10.5194/gmd-16-2719-2023 14 June 2023 It is hard for scientists to write code which is efficient on different kinds of supercomputers. Python is popular for its user-friendliness. We converted a Fortran code, simulating Earth’s atmosphere, into Python. This new code auto-converts to a faster language for processors or graphic cards. Our code runs 3.5–4 times faster on graphic cards than the original on processors in a specific supercomputer system. Read more
Causal deep learning models for studying the Earth system Geoscientific Model Development DOI 10.5194/gmd-16-2149-2023 12 May 2023 A recent statistical approach for studying relations in the Earth system is to train deep learning (DL) models to predict Earth system variables given one or several others and use interpretable DL to analyse the relations learned by the models. Here, we propose to combine the approach with a theorem from causality research to ensure that the deep learning model learns causal rather than spurious relations. As an example, we apply the method to study soil-moisture–precipitation coupling. Read more
Porting the WAVEWATCH III (v6.07) wave action source terms to GPU Geoscientific Model Development DOI 10.5194/gmd-16-1445-2023 3 May 2023 Wind-generated waves play an important role in modifying physical processes at the air–sea interface, but they have been traditionally excluded from climate models due to the high computational cost of running spectral wave models for climate simulations. To address this, our work identified and accelerated the computationally intensive section of WAVEWATCH III on GPU using OpenACC. This allows for high-resolution modelling of atmosphere–wave–ocean feedbacks in century-scale climate integrations. WAVEWATCH III (v6.07) wave action source terms to GPU">Read more
Reproducible and relocatable regional ocean modelling: fundamentals and practices Geoscientific Model Development DOI 10.5194/gmd-16-1481-2023 10 April 2023 The aim is to increase the capacity of the modelling community to respond to societally important questions that require ocean modelling. The concept of reproducibility for regional ocean modelling is developed: advocating methods for reproducible workflows and standardised methods of assessment. Then, targeting the NEMO framework, we give practical advice and worked examples, highlighting key considerations that will the expedite development cycle and upskill the user community. Read more
Introducing CRYOWRF v1.0: multiscale atmospheric flow simulations with advanced snow cover modelling Geoscientific Model Development DOI 10.5194/gmd-16-719-2023 10 March 2023 Most current generation climate and weather models have a relatively simplistic description of snow and snow–atmosphere interaction. One reason for this is the belief that including an advanced snow model would make the simulations too computationally demanding. In this study, we bring together two state-of-the-art models for atmosphere (WRF) and snow cover (SNOWPACK) and highlight both the feasibility and necessity of such coupled models to explore underexplored phenomena in the cryosphere. CRYOWRF v1.0: multiscale atmospheric flow simulations with advanced snow cover modelling">Read more