Articles | Volume 15, issue 3
https://doi.org/10.5194/gmd-15-1079-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-15-1079-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Methods for assessment of models
| 
04 Feb 2022
Methods for assessment of models |
| 04 Feb 2022
| 04 Feb 2022
Integration-based extraction and visualization of jet stream cores
Lukas Bösiger
Department of Computer Science, ETH Zurich, Zurich, Switzerland
Michael Sprenger
Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland
Maxi Boettcher
Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland
Hanna Joos
Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland
Department of Computer Science, FAU Erlangen-Nürnberg, Erlangen, Germany
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Jacopo Riboldi, Robin Noyelle, Ellina Agayar, Hanin Binder, Marc Federer, Katharina Hartmuth, Michael Sprenger, Iris Thurnherr, and Selvakumar Vishnupriya
EGUsphere, https://doi.org/10.5194/egusphere-2025-3599, https://doi.org/10.5194/egusphere-2025-3599, 2025
This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
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Storm Boris hit central Europe in September 2024 with extreme precipitation and impacts: this work introduces a methodology to strengthen our comprehension of how global warming affects similar events, based on the incorporation of event-specific meteorological information. Furthermore, it contextualizes how the answer to the question "How will Boris-like storms change in a warmer climate?" depends on explicit and implicit methodological choices, with the aim to inform future research.
Huw Davies and Michael Sprenger
EGUsphere, https://doi.org/10.5194/egusphere-2025-3017, https://doi.org/10.5194/egusphere-2025-3017, 2025
This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
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The Stratospheric Polar Vortex (SPV) with its accompanying strong circumpolar jet is a dominant feature of the wintertime stratosphere. Evidence is presented that the SPV’s periphery often possesses distinctive sub-planetary scale features. The scale and dynamics of the features are linked to the break-up of an annular band of strong vorticity at the SPV’s periphery, and the latter’s aggregation into one or two vortices due to forcing from below bears comparison to Sudden Stratospheric Warming.
Killian P. Brennan, Michael Sprenger, André Walser, Marco Arpagaus, and Heini Wernli
Weather Clim. Dynam., 6, 645–668, https://doi.org/10.5194/wcd-6-645-2025, https://doi.org/10.5194/wcd-6-645-2025, 2025
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We studied severe hailstorms that occurred in Switzerland on 28 June 2021 using a weather prediction model to understand how they evolved. We found that the storms moved toward areas with more storm energy. Hailfall was quickly followed by heavy rain. Just before the storms died out, the air feeding them stopped coming from near the ground. We also observed a delay between different types of precipitation forming in the incoming air.
Ming Hon Franco Lee and Michael Sprenger
EGUsphere, https://doi.org/10.5194/egusphere-2025-1949, https://doi.org/10.5194/egusphere-2025-1949, 2025
This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
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Turbulence can occur in clear-air conditions at cruising altitude. From around 5000 clear-air turbulence events identified using aircraft measurements, nonlinear breaking of large-scale waves and rapidly ascending airstreams associated with cyclones are found concurrent with 40 % and 30 % of them respectively. The results further show that these weather systems may trigger turbulence by generating highly deformed flow or flow instability, improving our understanding of clear-air turbulence.
Selvakumar Vishnupriya, Michael Sprenger, Hanna Joos, and Heini Wernli
EGUsphere, https://doi.org/10.5194/egusphere-2025-1731, https://doi.org/10.5194/egusphere-2025-1731, 2025
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Extratropical cyclones feature rapidly ascending airstreams known as warm conveyor belts, which influence upper-level flow dynamics. This study classifies interactions of warm conveyor belts with the jet stream into four types: no interactions, ridges, blocks, and tropospheric cutoffs. We use reanalysis data to show that the interaction type depends more on the structure of the ambient flow than on the WCB properties, which improves the understanding of extratropical flow variability.
Nicolai Krieger, Heini Wernli, Michael Sprenger, and Christian Kühnlein
Weather Clim. Dynam., 6, 447–469, https://doi.org/10.5194/wcd-6-447-2025, https://doi.org/10.5194/wcd-6-447-2025, 2025
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This study investigates the Laseyer, a local windstorm in a narrow Swiss valley characterized by strong southeasterly winds during northwesterly ambient flow. Using large-eddy simulations (LESs) with 30 m grid spacing, this is the first study to reveal that the extreme gusts in the valley are caused by an amplifying interplay of two recirculation regions. Modifying terrain and ambient wind conditions affects the windstorm's intensity and highlights the importance of topographic details in LES.
Alexander Pietak, Langwen Huang, Luigi Fusco, Michael Sprenger, Sebastian Schemm, and Torsten Hoefler
EGUsphere, https://doi.org/10.5194/egusphere-2025-793, https://doi.org/10.5194/egusphere-2025-793, 2025
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
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As meteorological models grow in complexity, the volume of output data increases, making compression increasingly desirable. However, no specialized methods currently exist for compressing data in the Lagrangian frame. To address this gap, we developed psit, a pipeline for the lossy compression of Lagrangian flow data. In most cases, psit achieves performance that is equivalent or superior to non specialized alternatives, with compression errors behaving similar to measurement inaccuracies.
Killian P. Brennan, Iris Thurnherr, Michael Sprenger, and Heini Wernli
EGUsphere, https://doi.org/10.5194/egusphere-2025-918, https://doi.org/10.5194/egusphere-2025-918, 2025
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Hailstorms can cause severe damage to homes, crops, and infrastructure. Using high-resolution climate simulations, we tracked thousands of hailstorms across Europe to study future changes. Large hail will become more frequent, hail-covered areas will expand, and extreme hail combined with heavy rain will double. These shifts could increase risks for communities and businesses, highlighting the need for better preparedness and adaptation.
Marc Federer, Lukas Papritz, Michael Sprenger, and Christian M. Grams
Weather Clim. Dynam., 6, 211–230, https://doi.org/10.5194/wcd-6-211-2025, https://doi.org/10.5194/wcd-6-211-2025, 2025
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Although extratropical cyclones in the North Atlantic are among the most impactful midlatitude weather systems, their intensification is not entirely understood. Here, we explore how individual cyclones convert available potential energy (APE) into kinetic energy and relate these conversions to the synoptic development of the cyclones. By combining potential vorticity thinking with a local APE framework, we offer a novel perspective on established concepts in dynamic meteorology.
Philip Rupp, Jonas Spaeth, Hilla Afargan-Gerstman, Dominik Büeler, Michael Sprenger, and Thomas Birner
Weather Clim. Dynam., 5, 1287–1298, https://doi.org/10.5194/wcd-5-1287-2024, https://doi.org/10.5194/wcd-5-1287-2024, 2024
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We quantify the occurrence of strong synoptic storms as contributing about 20 % to the uncertainty of subseasonal geopotential height forecasts over northern Europe. We further show that North Atlantic storms are less frequent, weaker and shifted southward following sudden stratospheric warming events, leading to a reduction in northern European forecast uncertainty.
Emmanouil Flaounas, Stavros Dafis, Silvio Davolio, Davide Faranda, Christian Ferrarin, Katharina Hartmuth, Assaf Hochman, Aristeidis Koutroulis, Samira Khodayar, Mario Marcello Miglietta, Florian Pantillon, Platon Patlakas, Michael Sprenger, and Iris Thurnherr
EGUsphere, https://doi.org/10.5194/egusphere-2024-2809, https://doi.org/10.5194/egusphere-2024-2809, 2024
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Storm Daniel (2023) is one of the most catastrophic ones ever documented in the Mediterranean. Our results highlight the different dynamics and therefore the different predictability skill of precipitation, its extremes and impacts that have been produced in Greece and Libya, the two most affected countries. Our approach concerns a holistic analysis of the storm by articulating dynamics, weather prediction, hydrological and oceanographic implications, climate extremes and attribution theory.
Katharina Heitmann, Michael Sprenger, Hanin Binder, Heini Wernli, and Hanna Joos
Weather Clim. Dynam., 5, 537–557, https://doi.org/10.5194/wcd-5-537-2024, https://doi.org/10.5194/wcd-5-537-2024, 2024
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Warm conveyor belts (WCBs) are coherently ascending air streams that occur in extratropical cyclones where they form precipitation and often affect the large-scale flow. We quantified the key characteristics and impacts of WCBs and linked them to different phases in the cyclone life cycle and to different WCB branches. A climatology of these metrics revealed that WCBs are most intense during cyclone intensification and that the cyclonic and anticyclonic WCB branches show distinct differences.
Lukas Jansing, Lukas Papritz, and Michael Sprenger
Weather Clim. Dynam., 5, 463–489, https://doi.org/10.5194/wcd-5-463-2024, https://doi.org/10.5194/wcd-5-463-2024, 2024
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Using an innovative approach, the descent of foehn is diagnosed from a Lagrangian perspective based on 15 kilometer-scale simulations combined with online trajectories. The descent is confined to distinct hotspots in the immediate lee of local mountain peaks and chains. Two detailed case studies reveal a varying wave regime to be associated with the descent. Furthermore, additional controlling factors, such as the diurnal cycle, likewise influence the descent activity.
Hilla Afargan-Gerstman, Dominik Büeler, C. Ole Wulff, Michael Sprenger, and Daniela I. V. Domeisen
Weather Clim. Dynam., 5, 231–249, https://doi.org/10.5194/wcd-5-231-2024, https://doi.org/10.5194/wcd-5-231-2024, 2024
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The stratosphere is a layer of Earth's atmosphere found above the weather systems. Changes in the stratosphere can affect the winds and the storm tracks in the North Atlantic region for a relatively long time, lasting for several weeks and even months. We show that the stratosphere can be important for weather forecasts beyond 1 week, but more work is needed to improve the accuracy of these forecasts for 3–4 weeks.
Yonatan Givon, Or Hess, Emmanouil Flaounas, Jennifer Louise Catto, Michael Sprenger, and Shira Raveh-Rubin
Weather Clim. Dynam., 5, 133–162, https://doi.org/10.5194/wcd-5-133-2024, https://doi.org/10.5194/wcd-5-133-2024, 2024
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A novel classification of Mediterranean cyclones is presented, enabling a separation between storms driven by different atmospheric processes. The surface impact of each cyclone class differs greatly by precipitation, winds, and temperatures, providing an invaluable tool to study the climatology of different types of Mediterranean storms and enhancing the understanding of their predictability, on both weather and climate scales.
Stefania Gilardoni, Dominic Heslin-Rees, Mauro Mazzola, Vito Vitale, Michael Sprenger, and Radovan Krejci
Atmos. Chem. Phys., 23, 15589–15607, https://doi.org/10.5194/acp-23-15589-2023, https://doi.org/10.5194/acp-23-15589-2023, 2023
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Models still fail in reproducing black carbon (BC) temporal variability in the Arctic. Analysis of equivalent BC concentrations in the European Arctic shows that BC seasonal variability is modulated by the efficiency of removal by precipitation during transport towards high latitudes. Short-term variability is controlled by synoptic-scale circulation patterns. The advection of warm air from lower latitudes is an effective pollution transport pathway during summer.
Thomas Trickl, Martin Adelwart, Dina Khordakova, Ludwig Ries, Christian Rolf, Michael Sprenger, Wolfgang Steinbrecht, and Hannes Vogelmann
Atmos. Meas. Tech., 16, 5145–5165, https://doi.org/10.5194/amt-16-5145-2023, https://doi.org/10.5194/amt-16-5145-2023, 2023
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Tropospheric ozone have been measured for more than a century. Highly quantitative ozone measurements have been made at monitoring stations. However, deficits have been reported for vertical sounding systems. Here, we report a thorough intercomparison effort between a differential-absorption lidar system and two types of balloon-borne ozone sondes, also using ozone sensors at nearby mountain sites as references. The sondes agree very well with the lidar after offset corrections.
Melanie Lauer, Annette Rinke, Irina Gorodetskaya, Michael Sprenger, Mario Mech, and Susanne Crewell
Atmos. Chem. Phys., 23, 8705–8726, https://doi.org/10.5194/acp-23-8705-2023, https://doi.org/10.5194/acp-23-8705-2023, 2023
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We present a new method to analyse the influence of atmospheric rivers (ARs), cyclones, and fronts on the precipitation in the Arctic, based on two campaigns: ACLOUD (early summer 2017) and AFLUX (early spring 2019). There are differences between both campaign periods: in early summer, the precipitation is mostly related to ARs and fronts, especially when they are co-located, while in early spring, cyclones isolated from ARs and fronts contributed most to the precipitation.
Emmanouil Flaounas, Leonardo Aragão, Lisa Bernini, Stavros Dafis, Benjamin Doiteau, Helena Flocas, Suzanne L. Gray, Alexia Karwat, John Kouroutzoglou, Piero Lionello, Mario Marcello Miglietta, Florian Pantillon, Claudia Pasquero, Platon Patlakas, María Ángeles Picornell, Federico Porcù, Matthew D. K. Priestley, Marco Reale, Malcolm J. Roberts, Hadas Saaroni, Dor Sandler, Enrico Scoccimarro, Michael Sprenger, and Baruch Ziv
Weather Clim. Dynam., 4, 639–661, https://doi.org/10.5194/wcd-4-639-2023, https://doi.org/10.5194/wcd-4-639-2023, 2023
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Cyclone detection and tracking methods (CDTMs) have different approaches in defining and tracking cyclone centers. This leads to disagreements on extratropical cyclone climatologies. We present a new approach that combines tracks from individual CDTMs to produce new composite tracks. These new tracks are shown to correspond to physically meaningful systems with distinctive life stages.
Hanna Joos, Michael Sprenger, Hanin Binder, Urs Beyerle, and Heini Wernli
Weather Clim. Dynam., 4, 133–155, https://doi.org/10.5194/wcd-4-133-2023, https://doi.org/10.5194/wcd-4-133-2023, 2023
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Warm conveyor belts (WCBs) are strongly ascending, cloud- and precipitation-forming airstreams in extratropical cyclones. In this study we assess their representation in a climate simulation and their changes under global warming. They become moister, become more intense, and reach higher altitudes in a future climate, implying that they potentially have an increased impact on the mid-latitude flow.
Andreas Schäfler, Michael Sprenger, Heini Wernli, Andreas Fix, and Martin Wirth
Atmos. Chem. Phys., 23, 999–1018, https://doi.org/10.5194/acp-23-999-2023, https://doi.org/10.5194/acp-23-999-2023, 2023
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In this study, airborne lidar profile measurements of H2O and O3 across a midlatitude jet stream are combined with analyses in tracer–trace space and backward trajectories. We highlight that transport and mixing processes in the history of the observed air masses are governed by interacting tropospheric weather systems on synoptic timescales. We show that these weather systems play a key role in the high variability of the paired H2O and O3 distributions near the tropopause.
Hanin Binder, Hanna Joos, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 4, 19–37, https://doi.org/10.5194/wcd-4-19-2023, https://doi.org/10.5194/wcd-4-19-2023, 2023
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Warm conveyor belts (WCBs) are the main cloud- and precipitation-producing airstreams in extratropical cyclones. The latent heat release that occurs during cloud formation often contributes to the intensification of the associated cyclone. Based on the Community Earth System Model Large Ensemble coupled climate simulations, we show that WCBs and associated latent heating will become stronger in a future climate and be even more important for explosive cyclone intensification than in the present.
Michael A. Barnes, Thando Ndarana, Michael Sprenger, and Willem A. Landman
Weather Clim. Dynam., 3, 1291–1309, https://doi.org/10.5194/wcd-3-1291-2022, https://doi.org/10.5194/wcd-3-1291-2022, 2022
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Stratospheric air can intrude into the troposphere and is associated with cyclonic development throughout the atmosphere. Through a highly idealized systematic approach, the effect that different intrusion characteristics have on surface cyclogenetic forcing is investigated. The proximity of stratospheric intrusions to the surface is shown to be the main factor in surface cyclogenetic forcing, whilst its width is an additional contributing factor.
Lukas Jansing, Lukas Papritz, Bruno Dürr, Daniel Gerstgrasser, and Michael Sprenger
Weather Clim. Dynam., 3, 1113–1138, https://doi.org/10.5194/wcd-3-1113-2022, https://doi.org/10.5194/wcd-3-1113-2022, 2022
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This study presents a 5-year climatology of three main foehn types and three deep-foehn subtypes. The main types differ in their large-scale and Alpine-scale weather conditions and the subtypes in terms of the amount and extent of precipitation on the Alpine south side. The different types of foehn are found to strongly affect the local meteorological conditions at Altdorf. The study concludes by setting the new classification into a historic context.
Jan Clemens, Felix Ploeger, Paul Konopka, Raphael Portmann, Michael Sprenger, and Heini Wernli
Atmos. Chem. Phys., 22, 3841–3860, https://doi.org/10.5194/acp-22-3841-2022, https://doi.org/10.5194/acp-22-3841-2022, 2022
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Highly polluted air flows from the surface to higher levels of the atmosphere during the Asian summer monsoon. At high levels, the air is trapped within eddies. Here, we study how air masses can leave the eddy within its cutoff, how they distribute, and how their chemical composition changes. We found evidence for transport from the eddy to higher latitudes over the North Pacific and even Alaska. During transport, trace gas concentrations within cutoffs changed gradually, showing steady mixing.
Jörg Wieder, Claudia Mignani, Mario Schär, Lucie Roth, Michael Sprenger, Jan Henneberger, Ulrike Lohmann, Cyril Brunner, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 3111–3130, https://doi.org/10.5194/acp-22-3111-2022, https://doi.org/10.5194/acp-22-3111-2022, 2022
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We investigate the variation in ice-nucleating particles (INPs) relevant for primary ice formation in mixed-phased clouds over the Alps based on simultaneous in situ observations at a mountaintop and a nearby high valley (1060 m height difference). In most cases, advection from the surrounding lower regions was responsible for changes in INP concentration, causing a diurnal cycle at the mountaintop. Our study underlines the importance of the planetary boundary layer as an INP reserve.
Katharina Hartmuth, Maxi Boettcher, Heini Wernli, and Lukas Papritz
Weather Clim. Dynam., 3, 89–111, https://doi.org/10.5194/wcd-3-89-2022, https://doi.org/10.5194/wcd-3-89-2022, 2022
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In this study, we introduce a novel method to objectively define and identify extreme Arctic seasons based on different surface variables. We find that such seasons are resulting from various combinations of unusual seasonal conditions. The occurrence or absence of different atmospheric processes strongly affects the character of extreme Arctic seasons. Further, changes in sea ice and sea surface temperature can strongly influence the formation of such a season in distinct regions.
Leonie Villiger, Heini Wernli, Maxi Boettcher, Martin Hagen, and Franziska Aemisegger
Weather Clim. Dynam., 3, 59–88, https://doi.org/10.5194/wcd-3-59-2022, https://doi.org/10.5194/wcd-3-59-2022, 2022
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The coupling between the large-scale atmospheric circulation and the clouds in the trade-wind region is complex and not yet fully understood. In this study, the formation pathway of two anomalous cloud layers over Barbados during the field campaign EUREC4A is described. The two case studies highlight the influence of remote weather systems on the local environmental conditions in Barbados.
Roman Attinger, Elisa Spreitzer, Maxi Boettcher, Heini Wernli, and Hanna Joos
Weather Clim. Dynam., 2, 1073–1091, https://doi.org/10.5194/wcd-2-1073-2021, https://doi.org/10.5194/wcd-2-1073-2021, 2021
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Diabatic processes affect the development of extratropical cyclones. This work provides a systematic assessment of the diabatic processes that modify potential vorticity (PV) in model simulations. PV is primarily produced by condensation and convection. Given favorable environmental conditions, long-wave radiative cooling and turbulence become the primary process at the cold and warm fronts, respectively. Turbulence and long-wave radiative heating produce negative PV anomalies at the fronts.
Philippe Besson, Luise J. Fischer, Sebastian Schemm, and Michael Sprenger
Weather Clim. Dynam., 2, 991–1009, https://doi.org/10.5194/wcd-2-991-2021, https://doi.org/10.5194/wcd-2-991-2021, 2021
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The strongest cyclone intensification is associated with a strong dry-dynamical forcing. Moreover, strong forcing and strong intensification correspond to a tendency for poleward cyclone propagation, which occurs in distinct regions in the Northern Hemisphere. There is a clear spatial pattern in the occurrence of certain forcing combinations. This implies a fundamental relationship between dry-dynamical processes and the intensification as well as the propagation of extratropical cyclones.
Raphael Portmann, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 2, 507–534, https://doi.org/10.5194/wcd-2-507-2021, https://doi.org/10.5194/wcd-2-507-2021, 2021
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We explore the three-dimensional life cycle of cyclonic structures
(so-called PV cutoffs) near the tropopause. PV cutoffs are frequent weather systems in the extratropics that lead to high-impact weather. However, many unknowns exist regarding their evolution. We present a new method to track PV cutoffs as 3D objects in reanalysis data by following air parcels along the flow. We study the climatological life cycles of PV cutoffs in detail and propose a classification into three types.
Iris Thurnherr, Katharina Hartmuth, Lukas Jansing, Josué Gehring, Maxi Boettcher, Irina Gorodetskaya, Martin Werner, Heini Wernli, and Franziska Aemisegger
Weather Clim. Dynam., 2, 331–357, https://doi.org/10.5194/wcd-2-331-2021, https://doi.org/10.5194/wcd-2-331-2021, 2021
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Extratropical cyclones are important for the transport of moisture from low to high latitudes. In this study, we investigate how the isotopic composition of water vapour is affected by horizontal temperature advection associated with extratropical cyclones using measurements and modelling. It is shown that air–sea moisture fluxes induced by this horizontal temperature advection lead to the strong variability observed in the isotopic composition of water vapour in the marine boundary layer.
Maxi Boettcher, Andreas Schäfler, Michael Sprenger, Harald Sodemann, Stefan Kaufmann, Christiane Voigt, Hans Schlager, Donato Summa, Paolo Di Girolamo, Daniele Nerini, Urs Germann, and Heini Wernli
Atmos. Chem. Phys., 21, 5477–5498, https://doi.org/10.5194/acp-21-5477-2021, https://doi.org/10.5194/acp-21-5477-2021, 2021
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Warm conveyor belts (WCBs) are important airstreams in extratropical cyclones, often leading to the formation of intense precipitation. We present a case study that involves aircraft, lidar and radar observations of water and clouds in a WCB ascending from western Europe across the Alps towards the Baltic Sea during the field campaigns HyMeX and T-NAWDEX-Falcon in October 2012. A probabilistic trajectory measure and an airborne tracer experiment were used to confirm the long pathway of the WCB.
Melissa L. Breeden, Amy H. Butler, John R. Albers, Michael Sprenger, and Andrew O'Neil Langford
Atmos. Chem. Phys., 21, 2781–2794, https://doi.org/10.5194/acp-21-2781-2021, https://doi.org/10.5194/acp-21-2781-2021, 2021
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Prior research has found a maximum in deep stratosphere-to-troposphere mass/ozone transport over the western United States in boreal spring, which can enhance surface ozone concentrations, reducing air quality. We find that the winter-to-summer evolution of the north Pacific jet increases the frequency of stratospheric intrusions that drive transport, helping explain the observed maximum. The El Niño–Southern Oscillation affects the timing of the spring jet transition and therefore transport.
Annika Oertel, Michael Sprenger, Hanna Joos, Maxi Boettcher, Heike Konow, Martin Hagen, and Heini Wernli
Weather Clim. Dynam., 2, 89–110, https://doi.org/10.5194/wcd-2-89-2021, https://doi.org/10.5194/wcd-2-89-2021, 2021
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Convection embedded in the stratiform cloud band of strongly ascending airstreams in extratropical cyclones (so-called warm conveyor belts) can influence not only surface precipitation but also the
upper-tropospheric potential vorticity (PV) and waveguide. The comparison of intense vs. moderate embedded convection shows that its strength alone is not a reliable measure for upper-tropospheric PV modification. Instead, characteristics of the ambient flow co-determine its dynamical significance.
Emmanouil Flaounas, Matthias Röthlisberger, Maxi Boettcher, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 2, 71–88, https://doi.org/10.5194/wcd-2-71-2021, https://doi.org/10.5194/wcd-2-71-2021, 2021
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In this study we identify the wettest seasons globally and address their meteorological characteristics. We show that in different regions the wettest seasons occur in different times of the year and result from either unusually high frequencies of wet days and/or daily extremes. These high frequencies can be largely attributed to four specific weather systems, especially cyclones. Our analysis uses a thoroughly explained, novel methodology that could also be applied to climate models.
Claudia Mignani, Jörg Wieder, Michael A. Sprenger, Zamin A. Kanji, Jan Henneberger, Christine Alewell, and Franz Conen
Atmos. Chem. Phys., 21, 657–664, https://doi.org/10.5194/acp-21-657-2021, https://doi.org/10.5194/acp-21-657-2021, 2021
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Most precipitation above land starts with ice in clouds. It is promoted by extremely rare particles. Some ice-nucleating particles (INPs) cause cloud droplets to already freeze above −15°C, a temperature at which many clouds begin to snow. We found that the abundance of such INPs among other particles of similar size is highest in precipitating air masses and lowest when air carries desert dust. This brings us closer to understanding the interactions between land, clouds, and precipitation.
Stefan Rüdisühli, Michael Sprenger, David Leutwyler, Christoph Schär, and Heini Wernli
Weather Clim. Dynam., 1, 675–699, https://doi.org/10.5194/wcd-1-675-2020, https://doi.org/10.5194/wcd-1-675-2020, 2020
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Most precipitation over Europe is linked to low-pressure systems, cold fronts, warm fronts, or high-pressure systems. Based on a massive computer simulation able to resolve thunderstorms, we quantify in detail how much precipitation these weather systems produced during 2000–2008. We find distinct seasonal and regional differences, such as fronts precipitating a lot in fall and winter over the North Atlantic but high-pressure systems mostly in summer over the continent by way of thunderstorms.
Raphael Portmann, Juan Jesús González-Alemán, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 1, 597–615, https://doi.org/10.5194/wcd-1-597-2020, https://doi.org/10.5194/wcd-1-597-2020, 2020
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In September 2018 an intense Mediterranean cyclone with structural similarities to a hurricane, a so-called medicane, caused severe damage in Greece. Its development was uncertain, even just a few days in advance. The reason for this was uncertainties in the jet stream over the North Atlantic 3 d prior to cyclogenesis that propagated into the Mediterranean. They led to an uncertain position of the upper-level disturbance and, as a result, of the position and thermal structure of the cyclone.
Hanin Binder, Maxi Boettcher, Hanna Joos, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 1, 577–595, https://doi.org/10.5194/wcd-1-577-2020, https://doi.org/10.5194/wcd-1-577-2020, 2020
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Warm conveyor belts (WCBs) are important cloud- and
precipitation-producing airstreams in extratropical cyclones. By combining satellite observations with model data from a new reanalysis dataset, this study provides detailed observational insight into the vertical cloud structure of WCBs. We find that the reanalyses essentially capture the observed cloud pattern, but the observations reveal mesoscale structures not resolved by the temporally and spatially much coarser-resolution model data.
Sebastian Schemm, Stefan Rüdisühli, and Michael Sprenger
Weather Clim. Dynam., 1, 459–479, https://doi.org/10.5194/wcd-1-459-2020, https://doi.org/10.5194/wcd-1-459-2020, 2020
Short summary
Short summary
Troughs and ridges are ubiquitous flow features in the upper troposphere and are centerpiece elements of weather and climate research. A novel method is introduced to identify and track the life cycle of troughs and ridges and their orientation. The aim is to close the existing gap between methods that detect the initiation phase and methods that detect the decaying phase of Rossby wave development. Global climatologies, the influence of ENSO and Lagrangian characteristics are discussed.
Cited articles
Akritidis, D., Pozzer, A., Zanis, P., Tyrlis, E., Škerlak, B., Sprenger, M., and Lelieveld, J.: On the role of tropopause folds in summertime tropospheric ozone over the eastern Mediterranean and the Middle East, Atmos. Chem. Phys., 16, 14025–14039, https://doi.org/10.5194/acp-16-14025-2016, 2016. a
Archer, C. L. and Caldeira, K.: Historical trends in the jet streams,
Geophys. Res. Lett., 35, https://doi.org/10.1029/2008GL033614, 2008. a
Bader, R., Sprenger, M., Ban, N., Rüdisühli, S., Schär, C., and
Günther, T.: Extraction and Visual Analysis of Potential Vorticity Banners
around the Alps, IEEE T. Vis. Comput. Gr., 26, 259–269, https://doi.org/10.1109/TVCG.2019.2934310, 2020. a, b
Banks, D. and Singer, B.: Vortex tubes in turbulent flows: identification,
representation, reconstruction, in: Proceedings Visualization '94, IEEE Computer Society, Los Alamitos, CA, USA, 21 October 1994, 132–139,
https://doi.org/10.1109/VISUAL.1994.346327, 1994. a, b, c, d
Barton, N. P. and Ellis, A. W.: Variability in wintertime position and strength
of the North Pacific jet stream as represented by re-analysis data,
Int. J. Climatol., 29, 851–862, https://doi.org/10.1002/joc.1750,
2009. a
Binder, H., Boettcher, M., Joos, H., and Wernli, H.: The Role of Warm Conveyor
Belts for the Intensification of Extratropical Cyclones in Northern
Hemisphere Winter, J. Atmos. Sci., 73, 3997–4020,
https://doi.org/10.1175/JAS-D-15-0302.1, 2016. a
Blanchard, N., Pantillon, F., Chaboureau, J.-P., and Delanoë, J.: Mid-level convection in a warm conveyor belt accelerates the jet stream, Weather Clim. Dynam., 2, 37–53, https://doi.org/10.5194/wcd-2-37-2021, 2021. a, b
Blanco, J. L. and Rai, P. K.: nanoflann: a C
Bösiger, L., Sprenger, M., Boettcher, M., Joos, H., and Günther, T.: Integration-based Extraction and Visualization of Jet Stream Cores – Demo Data, Zenodo [data set], https://doi.org/10.5281/zenodo.5567866, 2021a. a
Bösiger, L., Sprenger, M., Boettcher, M., Joos, H., and Günther, T.: Integration-based Extraction and Visualization of Jet Stream Cores – Source Code, Zenodo [code], https://doi.org/10.5281/zenodo.5567863, 2021b. a
Bösiger, L., Sprenger, M., Boettcher, M., Joos, H., and Günther, T.: Integration-based Extraction and Visualization of Jet Stream Cores – Supplemental Video, Zenodo, https://doi.org/10.5281/zenodo.5722311, 2021c. a
Breeden, M. L., Butler, A. H., Albers, J. R., Sprenger, M., and Langford, A. O.: The spring transition of the North Pacific jet and its relation to deep stratosphere-to-troposphere mass transport over western North America, Atmos. Chem. Phys., 21, 2781–2794, https://doi.org/10.5194/acp-21-2781-2021, 2021. a
Cunningham, P. and Keyser, D.: Jet streaks, in: Encyclopedia of Atmospheric
Sciences, second edn., edited by: North, G. R., Pyle, J., and Zhang, F., Academic Press, Oxford, UK, 359–369, https://doi.org/10.1016/B978-0-12-382225-3.00187-0, 2015. a
Dameris, M.: Stratosphere/Troposphere exchange and structure | Tropopause, in:
Encyclopedia of Atmospheric Sciences, second edn., edited by: North,
G. R., Pyle, J., and Zhang, F., Academic Press, Oxford, UK, 269–272, https://doi.org/10.1016/B978-0-12-382225-3.00418-7, 2015. a, b
Danielsen, E. F.: Stratospheric-Tropospheric Exchange Based on Radioactivity,
Ozone and Potential Vorticity, J. Atmos. Sci., 25, 502–518,
https://doi.org/10.1175/1520-0469(1968)025<0502:STEBOR>2.0.CO;2, 1968. a
Davies, H. C.: Weather chains during the 2013/2014 winter and their
significance for seasonal prediction, Nat. Geosci., 8, 833–837, 2015. a
Eberly, D.: Ridges in Image and Data Analysis, Computational Imaging and
Vision, Springer Netherlands, Dordrecht, The Netherlands, https://doi.org/10.1007/978-94-015-8765-5, 1996. a
Eckermann, S.: Hybrid σ–p Coordinate Choices for a Global Model,
Mon. Weather Rev., 137, 224–245, https://doi.org/10.1175/2008MWR2537.1, 2009. a
Eckhardt, S., Stohl, A., Wernli, H., James, P., Forster, C., and Spichtinger,
N.: A 15-Year Climatology of Warm Conveyor Belts, J. Climate, 17,
218–237, https://doi.org/10.1175/1520-0442(2004)017<0218:AYCOWC>2.0.CO;2, 2004. a, b, c, d
Grams, C. M., Wernli, H., Böttcher, M., Ĉampa, J., Corsmeier, U., Jones,
S. C., Keller, J. H., Lenz, C.-J., and Wiegand, L.: The key role of diabatic
processes in modifying the upper-tropospheric wave guide: a North Atlantic
case-study, Q. J. Roy. Meteor. Soc., 137,
2174–2193, https://doi.org/10.1002/qj.891, 2011. a, b, c
Grams, C. M., Magnusson, L., and Madonna, E.: An atmospheric dynamics
perspective on the amplification and propagation of forecast error in
numerical weather prediction models: A case study, Q. J. Roy. Meteor. Soc., 144, 2577–2591,
https://doi.org/10.1002/qj.3353, 2018. a
Günther, T. and Theisel, H.: The State of the Art in Vortex Extraction,
Comput. Graph. Forum, 37, 149–173,
https://doi.org/10.1111/cgf.13319, 2018. a
Harnik, N., Garfinkel, C. I., and Lachmy, O.: The influence of jet stream
regime on extreme weather events, in: Dynamics and Predictability of Large-Scale, High-Impact Weather and Climate Events, 2, 79–94,
https://doi.org/10.1017/CBO9781107775541.007, 2016. a, b, c
Hersbach, H., Bell, B., Berrisford, P., Biavati, G., Horányi, A., Muñoz Sabater, J., Nicolas, J., Peubey, C., Radu, R., Rozum, I., Schepers, D., Simmons, A., Soci, C., Dee, D., and Thépaut, J.-N.: ERA5 hourly data on pressure levels from 1979 to present, Copernicus Climate Change Service [data set], https://doi.org/10.24381/cds.bd0915c6, 2018. a
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A.,
Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons,
A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati,
G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D.,
Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer,
A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M.,
Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P.,
Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global
reanalysis, Q. J. Roy. Meteor. Soc., 146,
1999–2049, https://doi.org/10.1002/qj.3803, 2020. a
Highwood, E. J., Hoskins, B. J., and Berrisford, P.: Properties of the arctic
tropopause, Q. J. Roy. Meteor. Soc., 126,
1515–1532, https://doi.org/10.1002/qj.49712656515, 2000. a, b
Holton, J. R., Haynes, P. H., McIntyre, M. E., Douglass, A. R., Rood, R. B.,
and Pfister, L.: Stratosphere-troposphere exchange, Rev. Geophys.,
33, 403–439, https://doi.org/10.1029/95RG02097, 1995. a
Hoskins, B. J., McIntyre, M. E., and Robertson, A. W.: On the use and
significance of isentropic potential vorticity maps, Q. J. Roy. Meteor. Soc., 111, 877–946, https://doi.org/10.1002/qj.49711147002, 1985. a
Joos, H. and Forbes, R. M.: Impact of different IFS microphysics on a warm
conveyor belt and the downstream flow evolution, Q. J. Roy. Meteor. Soc., 142, 2727–2739,
https://doi.org/10.1002/qj.2863, 2016. a
Kern, M. and Westermann, R.: Clustering Ensembles of 3D Jet-Stream Core
Lines, in: Vision, Modeling and Visualization, edited by: Schulz, H.-J.,
Teschner, M., and Wimmer, M., The Eurographics Association,
https://doi.org/10.2312/vmv.20191321, 2019. a, b
Kunz, A., Konopka, P., Müller, R., and Pan, L. L.: Dynamical tropopause based
on isentropic potential vorticity gradients, J. Geophys. Res.-Atmos., 116, D01110, https://doi.org/10.1029/2010JD014343, 2011. a, b
Lee, S. and Kim, H.-k.: The Dynamical Relationship between Subtropical and
Eddy-Driven Jets, J. Atmos. Sci., 60, 1490–1503,
https://doi.org/10.1175/1520-0469(2003)060<1490:TDRBSA>2.0.CO;2, 2003. a
Li, S., Jaroszynski, S., Pearse, S., Orf, L., and Clyne, J.: VAPOR: A
Visualization Package Tailored to Analyze Simulation Data in Earth System
Science, Atmosphere, 10, 488, https://doi.org/10.3390/atmos10090488, 2019. a
Lillo, S. P., Cavallo, S. M., Parsons, D. B., and Riedel, C.: The Role of a
Tropopause Polar Vortex in the Generation of the January 2019 Extreme Arctic
Outbreak, J. Atmos. Sci., 78, 2801–2821,
https://doi.org/10.1175/JAS-D-20-0285.1, 2021. a, b
Limbach, S., Schömer, E., and Wernli, H.: Detection, tracking and event localization of jet stream features in 4-D atmospheric data, Geosci. Model Dev., 5, 457–470, https://doi.org/10.5194/gmd-5-457-2012, 2012. a
Ljung, P. and Ynnerman, A.: Extraction of intersection curves from iso-surfaces
on co-located 3d grids, in: The Annual SIGRAD Conference. Special
Theme-Real-Time Simulations, Conference Proceedings from SIGRAD2003, Umeå, Sweden, 20–21 November 2003, 23–28, https://ep.liu.se/ecp/010/006/ecp01006.pdf (last access: 23 November 2022), 2003. a
Manney, G. L. and Hegglin, M. I.: Seasonal and Regional Variations of Long-Term
Changes in Upper-Tropospheric Jets from Reanalyses, J. Climate, 31,
423–448, https://doi.org/10.1175/JCLI-D-17-0303.1, 2018. a, b, c
Manney, G. L., Hegglin, M. I., Daffer, W. H., Santee, M. L., Ray, E. A., Pawson, S., Schwartz, M. J., Boone, C. D., Froidevaux, L., Livesey, N. J., Read, W. G., and Walker, K. A.: Jet characterization in the upper troposphere/lower stratosphere (UTLS): applications to climatology and transport studies, Atmos. Chem. Phys., 11, 6115–6137, https://doi.org/10.5194/acp-11-6115-2011, 2011. a, b, c
Manney, G. L., Hegglin, M. I., and Lawrence, Z. D.: Seasonal and regional
signatures of ENSO in upper tropospheric jet characteristics from reanalyses,
J. Climate, 34, 9181–9200, https://doi.org/10.1175/JCLI-D-20-0947.1, 2021. a
Martius, O.: A Lagrangian Analysis of the Northern Hemisphere Subtropical
Jet, J. Atmos. Sci., 71, 2354–2369,
https://doi.org/10.1175/JAS-D-13-0329.1, 2014. a
Martius, O., Schwierz, C., and Davies, H. C.: Tropopause-Level Waveguides,
J. Atmos. Sci., 67, 866–879,
https://doi.org/10.1175/2009JAS2995.1, 2010. a
Nielsen-Gammon, J. W.: A Visualization of the Global Dynamic Tropopause,
B. Am. Meteorol. Soc., 82, 1151–1168,
https://doi.org/10.1175/1520-0477(2001)082<1151:AVOTGD>2.3.CO;2, 2001. a, b, c
Oertel, A., Boettcher, M., Joos, H., Sprenger, M., Konow, H., Hagen, M., and
Wernli, H.: Convective activity in an extratropical cyclone and its warm
conveyor belt – a case-study combining observations and a
convection-permitting model simulation, Q. J. Roy. Meteor. Soc., 145, 1406–1426, https://doi.org/10.1002/qj.3500, 2019. a
Oertel, A., Boettcher, M., Joos, H., Sprenger, M., and Wernli, H.: Potential vorticity structure of embedded convection in a warm conveyor belt and its relevance for large-scale dynamics, Weather Clim. Dynam., 1, 127–153, https://doi.org/10.5194/wcd-1-127-2020, 2020. a, b
Peikert, R. and Roth, M.: The “Parallel Vectors” operator – a vector field
visualization primitive, in: Proceedings Visualization '99 (Cat.
No.99CB37067), San Francisco, CA, USA, 24–29 October 1999, 263–532, https://doi.org/10.1109/VISUAL.1999.809896, 1999. a, b, c, d
Pena-Ortiz, C., Gallego, D., Ribera, P., Ordonez, P., and Alvarez-Castro, M.
D. C.: Observed trends in the global jet stream characteristics during the
second half of the 20th century, J. Geophys. Res.-Atmos., 118, 2702–2713, https://doi.org/10.1002/jgrd.50305, 2013. a
Rautenhaus, M., Grams, C. M., Schäfler, A., and Westermann, R.: Three-dimensional visualization of ensemble weather forecasts – Part 2: Forecasting warm conveyor belt situations for aircraft-based field campaigns, Geosci. Model Dev., 8, 2355–2377, https://doi.org/10.5194/gmd-8-2355-2015, 2015a. a, b
Rautenhaus, M., Kern, M., Schäfler, A., and Westermann, R.: Three-dimensional visualization of ensemble weather forecasts – Part 1: The visualization tool Met.3D (version 1.0), Geosci. Model Dev., 8, 2329–2353, https://doi.org/10.5194/gmd-8-2329-2015, 2015b. a, b
Rautenhaus, M., Böttinger, M., Siemen, S., Hoffman, R., Kirby,
R. M., Mirzargar, M., Röber, N., and Westermann, R.: Visualization in
Meteorology - A Survey of Techniques and Tools for Data Analysis Tasks, IEEE T. Vis. Comput. Gr., 24, 3268–3296,
https://doi.org/10.1109/TVCG.2017.2779501, 2018. a, b
Raveh-Rubin, S.: Dry Intrusions: Lagrangian Climatology and Dynamical Impact on
the Planetary Boundary Layer, J. Climate, 30, 6661–6682,
https://doi.org/10.1175/JCLI-D-16-0782.1, 2017. a
Reiter, E. R. and Nania, A.: Jet-stream structure and clear-air turbulence
(CAT), J. Appl. Meteorol. Clim., 3, 247–260, 1964. a
Rodwell, M., Forbes, R., and Wernli, H.: Why warm conveyor belts matter in NWP, ECMWF newsletter, 21–28, https://doi.org/10.21957/mr20vg, 2018. a, b
Rodwell, M. J., Magnusson, L., Bauer, P., Bechtold, P., Bonavita, M.,
Cardinali, C., Diamantakis, M., Earnshaw, P., García-Méndez, A.,
Isaksen, L., Källén, E., Klocke, D., Lopez, P., McNally, T., Persson,
A., Prates, F., and Wedi, N.: Characteristics of occasional poor medium-range
weather forecasts for Europe, B. Am. Meteorol. Soc., 94, 1393–1405, 2013. a
Saffin, L., Methven, J., Bland, J., Harvey, B., and Sanchez, C.: Circulation
conservation in the outflow of warm conveyor belts and consequences for
Rossby wave evolution, Q. J. Roy. Meteor. Soc., 147, 3587–3610, https://doi.org/10.1002/qj.4143, 2021. a
Schiemann, R., Lüthi, D., and Schär, C.: Seasonality and Interannual
Variability of the Westerly Jet in the Tibetan Plateau Region, J. Climate, 22, 2940–2957, https://doi.org/10.1175/2008JCLI2625.1, 2009. a, b, c
Schoeberl, M. R.: Extratropical stratosphere-troposphere mass exchange, J. Geophys. Res.-Atmos., 109, D13303,
https://doi.org/10.1029/2004JD004525, 2004. a, b, c
Schroeder, W. J., Martin, K., and Lorensen, W. E.: The visualization toolkit,
4. edn., Kitware, Clifton Park, N.Y., 528 pp., ISBN 978 1930934191, 2006. a
Schultz, D. M., Bosart, L. F., Colle, B. A., Davies, H. C., Dearden, C.,
Keyser, D., Martius, O., Roebber, P. J., Steenburgh, W. J., Volkert, H., and
Winters, A. C.: Extratropical Cyclones: A Century of Research on
Meteorology's Centerpiece, Meteor. Mon., 59, 16.1–16.56,
https://doi.org/10.1175/AMSMONOGRAPHS-D-18-0015.1, 2019. a
Schäfler, A., Craig, G., Wernli, H., Arbogast, P., Doyle, J. D.,
McTaggart-Cowan, R., Methven, J., Rivière, G., Ament, F., Boettcher, M.,
Bramberger, M., Cazenave, Q., Cotton, R., Crewell, S., Delanoë, J.,
Dörnbrack, A., Ehrlich, A., Ewald, F., Fix, A., Grams, C. M., Gray, S. L.,
Grob, H., Groß, S., Hagen, M., Harvey, B., Hirsch, L., Jacob, M., Kölling,
T., Konow, H., Lemmerz, C., Lux, O., Magnusson, L., Mayer, B., Mech, M.,
Moore, R., Pelon, J., Quinting, J., Rahm, S., Rapp, M., Rautenhaus, M.,
Reitebuch, O., Reynolds, C. A., Sodemann, H., Spengler, T., Vaughan, G.,
Wendisch, M., Wirth, M., Witschas, B., Wolf, K., and Zinner, T.: The North
Atlantic Waveguide and Downstream Impact Experiment, B. Am. Meteorol. Soc., 99, 1607–1637, https://doi.org/10.1175/BAMS-D-17-0003.1, 2018. a
Shapiro, M. A.: Turbulent Mixing within Tropopause Folds as a Mechanism for the
Exchange of Chemical Constituents between the Stratosphere and Troposphere,
J. Atmos. Sci., 37, 994–1004,
https://doi.org/10.1175/1520-0469(1980)037<0994:TMWTFA>2.0.CO;2, 1980. a
Shapiro, M. A. and Keyser, D.: Fronts, jet streams and the tropopause, in:
Extratropical cyclones, American Meteorological Society, Boston, MA, USA, 167–191,
https://doi.org/10.1007/978-1-944970-33-8_10, 1990. a
Škerlak, B., Sprenger, M., Pfahl, S., Tyrlis, E., and Wernli, H.:
Tropopause folds in ERA-Interim: Global climatology and relation to extreme
weather events, J. Geophys. Res.-Atmos., 120,
4860–4877, https://doi.org/10.1002/2014JD022787, 2015. a, b
Spensberger, C. and Spengler, T.: Feature-Based Jet Variability in the Upper
Troposphere, J. Climate, 33, 6849–6871,
https://doi.org/10.1175/JCLI-D-19-0715.1, 2020. a
Spensberger, C., Spengler, T., and Li, C.: Upper-tropospheric jet axis
detection and application to the boreal winter 2013/14, Mon. Weather
Rev., 145, 2363–2374, 2017. a
Spreitzer, E. J.: Diabatic processes in mid-latitude weather systems – a study with the ECMWF model, Ph.D. thesis, ETH Zurich,
https://doi.org/10.3929/ethz-b-000438728, 2020. a
Sprenger, M., Croci Maspoli, M., and Wernli, H.: Tropopause folds and
cross-tropopause exchange: A global investigation based upon ECMWF analyses
for the time period March 2000 to February 2001, J. Geophys. Res.-Atmos., 108, 8518, https://doi.org/10.1029/2002JD002587, 2003.
a
Steinfeld, D., Boettcher, M., Forbes, R., and Pfahl, S.: The sensitivity of atmospheric blocking to upstream latent heating – numerical experiments, Weather Clim. Dynam., 1, 405–426, https://doi.org/10.5194/wcd-1-405-2020, 2020. a
Stohl, A., Bonasoni, P., Cristofanelli, P., Collins, W., Feichter, J., Frank,
A., Forster, C., Gerasopoulos, E., Gäggeler, H., James, P., Kentarchos, T.,
Kromp-Kolb, H., Krüger, B., Land, C., Meloen, J., Papayannis, A., Priller,
A., Seibert, P., Sprenger, M., Roelofs, G. J., Scheel, H. E., Schnabel, C.,
Siegmund, P., Tobler, L., Trickl, T., Wernli, H., Wirth, V., Zanis, P., and
Zerefos, C.: Stratosphere-troposphere exchange: A review, and what we have
learned from STACCATO, J. Geophys. Res.-Atmos., 108, 8516,
https://doi.org/10.1029/2002JD002490, 2003. a
Van Gelder, A. and Pang, A.: Using PVsolve to Analyze and Locate
Positions of Parallel Vectors, IEEE T. Vis. Comput. Gr., 15, 682–695, https://doi.org/10.1109/TVCG.2009.11, 2009. a
Weinkauf, T., Theisel, H., Van Gelder, A., and Pang, A.: Stable Feature
Flow Fields, IEEE T. Vis. Comput. Gr., 17, 770–780, https://doi.org/10.1109/TVCG.2010.93, 2011. a
Wernli, H.: A lagrangian-based analysis of extratropical cyclones. II: A
detailed case-study, Q. J. Roy. Meteor. Soc.,
123, 1677–1706, https://doi.org/10.1002/qj.49712354211, 1997. a, b
Wernli, H. and Schwierz, C.: Surface Cyclones in the ERA-40 Dataset
(1958–2001). Part I: Novel Identification Method and Global Climatology,
J. Atmos. Sci., 63, 2486–2507, https://doi.org/10.1175/JAS3766.1, 2006. a
Witschi, R. and Günther, T.: Implicit Ray Casting of the Parallel Vectors
Operator, in: IEEE Visualization – Short Papers, 25–30 October 2020, Salt Lake City, UT, USA, 31–35, https://doi.org/10.1109/VIS47514.2020.00013, 2020. a
Short summary
Jet streams are coherent air flows that interact with atmospheric structures such as warm conveyor belts (WCBs) and the tropopause. Individually, these structures have a significant impact on the weather evolution. A first step towards a deeper understanding of the meteorological processes is to extract jet stream core lines, for which we develop a novel feature extraction algorithm. Based on the line geometry, we automatically detect and visualize potential interactions between WCBs and jets.
Jet streams are coherent air flows that interact with atmospheric structures such as warm...
