Articles | Volume 2, issue 3
https://doi.org/10.5194/wcd-2-609-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wcd-2-609-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Large-scale drivers of the mistral wind: link to Rossby wave life cycles and seasonal variability
Yonatan Givon
CORRESPONDING AUTHOR
Department of Earth and Planetary Sciences, Weizmann
Institute of Science, Rehovot, Israel
Douglas Keller Jr.
Laboratoire de Météorologie Dynamique
– IPSL, École Polytechnique, Institut Polytechnique
de Paris, ENS, PSL Research University, Sorbonne
Université, CNRS, Palaiseau, France
Vered Silverman
Department of Earth and Planetary Sciences, Weizmann
Institute of Science, Rehovot, Israel
Romain Pennel
Laboratoire de Météorologie Dynamique
– IPSL, École Polytechnique, Institut Polytechnique
de Paris, ENS, PSL Research University, Sorbonne
Université, CNRS, Palaiseau, France
Philippe Drobinski
Laboratoire de Météorologie Dynamique
– IPSL, École Polytechnique, Institut Polytechnique
de Paris, ENS, PSL Research University, Sorbonne
Université, CNRS, Palaiseau, France
Shira Raveh-Rubin
Department of Earth and Planetary Sciences, Weizmann
Institute of Science, Rehovot, Israel
Related authors
Douglas Keller Jr., Yonatan Givon, Romain Pennel, Shira Raveh-Rubin, and Philippe Drobinski
Ocean Sci., 18, 483–510, https://doi.org/10.5194/os-18-483-2022, https://doi.org/10.5194/os-18-483-2022, 2022
Short summary
Short summary
The mistral winds are believed to be the primary source of cooling of the Gulf of Lion, leading to deep convection in the region, a process that mixes the ocean column from the seafloor to the sea surface. However, we have found that seasonal atmospheric changes also significantly cool the Gulf of Lion waters to cause deep convection, rather than mistral winds being the sole source, contributing roughly two-thirds of the required cooling, with the mistral winds contributing the final third.
Sylvain Mailler, Romain Pennel, Laurent Menut, and Arineh Cholakian
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2023-78, https://doi.org/10.5194/gmd-2023-78, 2023
Preprint under review for GMD
Short summary
Short summary
We show that a new advection scheme named PPM+W ("Piecewise Parabolic Method + Walcek") offers geoscientific modellers an alternative, high-performance scheme designed for Cartesian-grid advection, with improved performance over the classical PPM scheme. The computational cost of PPM+W is not higher than that of PPM. With improved accuracy and controlled computational cost, this new scheme may find applications in chemistry-transport models, ocean models or atmospheric circulation models.
Laurent Menut, Arineh Cholakian, Guillaume Siour, Remy Lapere, Romain Pennel, Sylvain Mailler, and Bertrand Bessagnet
EGUsphere, https://doi.org/10.5194/egusphere-2023-421, https://doi.org/10.5194/egusphere-2023-421, 2023
Short summary
Short summary
This study is about the wildfires occuring in France during the summer 2022. We study the forest fires that took place in the Landes during the summer of 2022. We show the direct impact of these fires on the air quality, especially downstream of the smoke plume towards the Paris region. We quantify the impact of these fires on the pollutants peak concentrations and the possible exceedance of thresholds.
Sylvain Mailler, Laurent Menut, Arineh Cholakian, and Romain Pennel
Geosci. Model Dev., 16, 1119–1127, https://doi.org/10.5194/gmd-16-1119-2023, https://doi.org/10.5194/gmd-16-1119-2023, 2023
Short summary
Short summary
Large or even
giantparticles of mineral dust exist in the atmosphere but, so far, solving an non-linear equation was needed to calculate the speed at which they fall in the atmosphere. The model we present, AerSett v1.0 (AERosol SETTling version 1.0), provides a new and simple way of calculating their free-fall velocity in the atmosphere, which will be useful to anyone trying to understand and represent adequately the transport of giant dust particles by the wind.
Théo Le Guenedal, Philippe Drobinski, and Peter Tankov
Geosci. Model Dev., 15, 8001–8039, https://doi.org/10.5194/gmd-15-8001-2022, https://doi.org/10.5194/gmd-15-8001-2022, 2022
Short summary
Short summary
The CATHERINA model produces simulations of cyclone-related annualized damage costs at a country level from climate data and open-source socioeconomic indicators. The framework couples statistical and physical modeling of tropical cyclones to bridge the gap between general circulation and integrated assessment models providing a precise description of tropical-cyclone-related damages.
Daniel A. Knopf, Joseph C. Charnawskas, Peiwen Wang, Benny Wong, Jay M. Tomlin, Kevin A. Jankowski, Matthew Fraund, Daniel P. Veghte, Swarup China, Alexander Laskin, Ryan C. Moffet, Mary K. Gilles, Josephine Y. Aller, Matthew A. Marcus, Shira Raveh-Rubin, and Jian Wang
Atmos. Chem. Phys., 22, 5377–5398, https://doi.org/10.5194/acp-22-5377-2022, https://doi.org/10.5194/acp-22-5377-2022, 2022
Short summary
Short summary
Marine boundary layer aerosols collected in the remote region of the eastern North Atlantic induce immersion freezing and deposition ice nucleation under typical mixed-phase and cirrus cloud conditions. Corresponding ice nucleation parameterizations for model applications have been derived. Chemical imaging of ambient aerosol and ice-nucleating particles demonstrates that the latter is dominated by sea salt and organics while also representing a major particle type in the particle population.
Assaf Hochman, Francesco Marra, Gabriele Messori, Joaquim G. Pinto, Shira Raveh-Rubin, Yizhak Yosef, and Georgios Zittis
Earth Syst. Dynam., 13, 749–777, https://doi.org/10.5194/esd-13-749-2022, https://doi.org/10.5194/esd-13-749-2022, 2022
Short summary
Short summary
Gaining a complete understanding of extreme weather, from its physical drivers to its impacts on society, is important in supporting future risk reduction and adaptation measures. Here, we provide a review of the available scientific literature, knowledge gaps and key open questions in the study of extreme weather events over the vulnerable eastern Mediterranean region.
Douglas Keller Jr., Yonatan Givon, Romain Pennel, Shira Raveh-Rubin, and Philippe Drobinski
Ocean Sci., 18, 483–510, https://doi.org/10.5194/os-18-483-2022, https://doi.org/10.5194/os-18-483-2022, 2022
Short summary
Short summary
The mistral winds are believed to be the primary source of cooling of the Gulf of Lion, leading to deep convection in the region, a process that mixes the ocean column from the seafloor to the sea surface. However, we have found that seasonal atmospheric changes also significantly cool the Gulf of Lion waters to cause deep convection, rather than mistral winds being the sole source, contributing roughly two-thirds of the required cooling, with the mistral winds contributing the final third.
Emmanouil Flaounas, Silvio Davolio, Shira Raveh-Rubin, Florian Pantillon, Mario Marcello Miglietta, Miguel Angel Gaertner, Maria Hatzaki, Victor Homar, Samira Khodayar, Gerasimos Korres, Vassiliki Kotroni, Jonilda Kushta, Marco Reale, and Didier Ricard
Weather Clim. Dynam., 3, 173–208, https://doi.org/10.5194/wcd-3-173-2022, https://doi.org/10.5194/wcd-3-173-2022, 2022
Short summary
Short summary
This is a collective effort to describe the state of the art in Mediterranean cyclone dynamics, climatology, prediction (weather and climate scales) and impacts. More than that, the paper focuses on the future directions of research that would advance the broader field of Mediterranean cyclones as a whole. Thereby, we propose interdisciplinary cooperation and additional modelling and forecasting strategies, and we highlight the need for new impact-oriented approaches to climate prediction.
Jay M. Tomlin, Kevin A. Jankowski, Daniel P. Veghte, Swarup China, Peiwen Wang, Matthew Fraund, Johannes Weis, Guangjie Zheng, Yang Wang, Felipe Rivera-Adorno, Shira Raveh-Rubin, Daniel A. Knopf, Jian Wang, Mary K. Gilles, Ryan C. Moffet, and Alexander Laskin
Atmos. Chem. Phys., 21, 18123–18146, https://doi.org/10.5194/acp-21-18123-2021, https://doi.org/10.5194/acp-21-18123-2021, 2021
Short summary
Short summary
Analysis of individual atmospheric particles shows that aerosol transported from North America during meteorological dry intrusion episodes may have a substantial impact on the mixing state and particle-type population over the mid-Atlantic, as organic contribution and particle-type diversity are significantly enhanced during these periods. These observations need to be considered in current atmospheric models.
Laurent Menut, Bertrand Bessagnet, Régis Briant, Arineh Cholakian, Florian Couvidat, Sylvain Mailler, Romain Pennel, Guillaume Siour, Paolo Tuccella, Solène Turquety, and Myrto Valari
Geosci. Model Dev., 14, 6781–6811, https://doi.org/10.5194/gmd-14-6781-2021, https://doi.org/10.5194/gmd-14-6781-2021, 2021
Short summary
Short summary
The CHIMERE chemistry-transport model is presented in its new version, V2020r1. Many changes are proposed compared to the previous version. These include online modeling, new parameterizations for aerosols, new emissions schemes, a new parameter file format, the subgrid-scale variability of urban concentrations and new transport schemes.
Sylvain Mailler, Romain Pennel, Laurent Menut, and Mathieu Lachâtre
Geosci. Model Dev., 14, 2221–2233, https://doi.org/10.5194/gmd-14-2221-2021, https://doi.org/10.5194/gmd-14-2221-2021, 2021
Short summary
Short summary
Representing the advection of thin polluted plumes in numerical models is a challenging task since these models usually tend to excessively diffuse these plumes in the vertical direction. This numerical diffusion process is the cause of major difficulties in representing such dense and thin polluted plumes in numerical models. We propose here, and test in an academic framework, a novel method to solve this problem through the use of an antidiffusive advection scheme in the vertical direction.
Naama Reicher, Carsten Budke, Lukas Eickhoff, Shira Raveh-Rubin, Ifat Kaplan-Ashiri, Thomas Koop, and Yinon Rudich
Atmos. Chem. Phys., 19, 11143–11158, https://doi.org/10.5194/acp-19-11143-2019, https://doi.org/10.5194/acp-19-11143-2019, 2019
Short summary
Short summary
We characterized size-segregated airborne ice-nucleating particles (INPs) during dust storm events in the eastern Mediterranean. We found that particle size can predict its activity, and in general, larger particles are better INPs. The activity of supermicron particles dominated by desert mineral dust was similar between the different dust events regardless of the high variability of the geographic source desert and atmospheric journey.
Aurore Dupré, Philippe Drobinski, Jordi Badosa, Christian Briard, and Riwal Plougonven
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2019-88, https://doi.org/10.5194/angeo-2019-88, 2019
Manuscript not accepted for further review
Short summary
Short summary
In a context of climate change, the wind energy sector has seen a very sharp growth requiring accurate forecasts. Air density is a key variable in the wind energy modeling as it can make the power output varies by almost 20 %. In this paper, a numerically low-cost method is evaluated. This method improves the wind energy modeling by more than 15 % and by almost 40 % when the atmospheric conditions are far from the standards atmospheric conditions used to produce the wind turbine power curve.
Sophie Bastin, Philippe Drobinski, Marjolaine Chiriaco, Olivier Bock, Romain Roehrig, Clemente Gallardo, Dario Conte, Marta Domínguez Alonso, Laurent Li, Piero Lionello, and Ana C. Parracho
Atmos. Chem. Phys., 19, 1471–1490, https://doi.org/10.5194/acp-19-1471-2019, https://doi.org/10.5194/acp-19-1471-2019, 2019
Short summary
Short summary
This paper uses colocated observations of temperature, precipitation and humidity to investigate the triggering of precipitation. It shows that there is a critical value of humidity above which precipitation picks up. This critical value depends on T and varies spatially. It also analyses how this dependency is reproduced in regional climate simulations over Europe. Models with too little and too light precipitation have both lower critical value of humidity and higher probability to exceed it.
Nicolas Da Silva, Sylvain Mailler, and Philippe Drobinski
Ann. Geophys., 36, 321–335, https://doi.org/10.5194/angeo-36-321-2018, https://doi.org/10.5194/angeo-36-321-2018, 2018
Short summary
Short summary
Aerosols affect atmospheric dynamics because they absorb radiations (direct effects) and because they act as cloud condensation nuclei (indirect effects). The present study shows that aerosol indirect effects reduce summer precipitation in the Euro-Mediterranean region through reduction of the radiative heating of the surface and corresponding reductions of surface temperature, resulting in increased atmospheric stability in the presence of high aerosol loads.
Bénédicte Jourdier and Philippe Drobinski
Ann. Geophys., 35, 691–700, https://doi.org/10.5194/angeo-35-691-2017, https://doi.org/10.5194/angeo-35-691-2017, 2017
Short summary
Short summary
Wind resource assessments often rely on models of wind-speed statistics using a Weibull distribution. This study shows how its use impacts the prediction of the wind energy content and the power output. Three methods for fitting the Weibull distribution are tested (maximum likelihood, moments and WAsP). The first two methods overestimate the production up to 5 %. The WAsP method always produces errors lower than 2 %. A Rayleigh–Rice distribution is also tested and shows even better skill.
C. Hernandez, C. Keribin, P. Drobinski, and S. Turquety
Ann. Geophys., 33, 1495–1506, https://doi.org/10.5194/angeo-33-1495-2015, https://doi.org/10.5194/angeo-33-1495-2015, 2015
C. Hernandez, P. Drobinski, and S. Turquety
Ann. Geophys., 33, 931–939, https://doi.org/10.5194/angeo-33-931-2015, https://doi.org/10.5194/angeo-33-931-2015, 2015
C. Hernandez, P. Drobinski, S. Turquety, and J.-L. Dupuy
Nat. Hazards Earth Syst. Sci., 15, 1331–1341, https://doi.org/10.5194/nhess-15-1331-2015, https://doi.org/10.5194/nhess-15-1331-2015, 2015
Related subject area
Dynamical processes in midlatitudes
What distinguishes 100-year precipitation extremes over central European river catchments from more moderate extreme events?
Towards a holistic understanding of blocked regime dynamics through a combination of complementary diagnostic perspectives
Moist available potential energy of the mean state of the atmosphere and the thermodynamic potential for warm conveyor belts and convection
Large spread in the representation of compound long-duration dry and hot spells over Europe in CMIP5
Similarity and variability of blocked weather-regime dynamics in the Atlantic–European region
Anomalous subtropical zonal winds drive decreases in southern Australian frontal rain
Origin of low-tropospheric potential vorticity in Mediterranean cyclones
Robust poleward jet shifts in idealised baroclinic-wave life-cycle experiments with noisy initial conditions
Revisiting the wintertime emergent constraint of the southern hemispheric midlatitude jet response to global warming
The global atmospheric energy transport analysed by a wavelength-based scale separation
Thunderstorm Types in Europe
European heatwaves in present and future climate simulations: a Lagrangian analysis
Signatures of Eurasian heat waves in global Rossby wave spectra
Impact of grid spacing, convective parameterization and cloud microphysics in ICON simulations of a warm conveyor belt
Recurrent Rossby waves and south-eastern Australian heatwaves
Identification of high-wind features within extratropical cyclones using a probabilistic random forest – Part 1: Method and case studies
Classification of Alpine south foehn based on 5 years of kilometre-scale analysis data
Meridional-energy-transport extremes and the general circulation of Northern Hemisphere mid-latitudes: dominant weather regimes and preferred zonal wavenumbers
Summertime Rossby waves in climate models: substantial biases in surface imprint associated with small biases in upper-level circulation
Diabatic processes modulating the vertical structure of the jet stream above the cold front of an extratropical cyclone: sensitivity to deep convection schemes
The role of cyclones and potential vorticity cutoffs for the occurrence of unusually long wet spells in Europe
Orographic resolution driving the improvements associated with horizontal resolution increase in the Northern Hemisphere winter mid-latitudes
Quantifying climate model representation of the wintertime Euro-Atlantic circulation using geopotential-jet regimes
Circumglobal Rossby wave patterns during boreal winter highlighted by space–time spectral analysis
How intense daily precipitation depends on temperature and the occurrence of specific weather systems – an investigation with ERA5 reanalyses in the extratropical Northern Hemisphere
Differentiating lightning in winter and summer with characteristics of the wind field and mass field
Future changes in the extratropical storm tracks and cyclone intensity, wind speed, and structure
Atmospheric blocking and weather extremes over the Euro-Atlantic sector – a review
Is it north or west foehn? A Lagrangian analysis of Penetration and Interruption of Alpine Foehn intensive observation period 1 (PIANO IOP 1)
Past evolution of western Europe large-scale circulation and link to precipitation trend in the northern French Alps
How well is Rossby wave activity represented in the PRIMAVERA coupled simulations?
Mediterranean cyclones: current knowledge and open questions on dynamics, prediction, climatology and impacts
Automated detection and classification of synoptic-scale fronts from atmospheric data grids
Multi-day hail clusters and isolated hail days in Switzerland – large-scale flow conditions and precursors
Characteristics of extratropical cyclones and precursors to windstorms in northern Europe
Systematic assessment of the diabatic processes that modify low-level potential vorticity in extratropical cyclones
The impact of deep convection representation in a global atmospheric model on the warm conveyor belt and jet stream during NAWDEX IOP6
A global analysis of the dry-dynamic forcing during cyclone growth and propagation
Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatology
Occurrence and transition probabilities of omega and high-over-low blocking in the Euro-Atlantic region
Oceanic moisture sources contributing to wintertime Euro-Atlantic blocking
Reconstructing winter climate anomalies in the Euro-Atlantic sector using circulation patterns
Linking air stagnation in Europe with the synoptic- to large-scale atmospheric circulation
Relative importance of tropopause structure and diabatic heating for baroclinic instability
On the occurrence of strong vertical wind shear in the tropopause region: a 10-year ERA5 northern hemispheric study
An unsupervised learning approach to identifying blocking events: the case of European summer
Potential-vorticity dynamics of troughs and ridges within Rossby wave packets during a 40-year reanalysis period
The three-dimensional life cycles of potential vorticity cutoffs: a global and selected regional climatologies in ERA-Interim (1979–2018)
Influence of ENSO on North American subseasonal surface air temperature variability
A process-based anatomy of Mediterranean cyclones: from baroclinic lows to tropical-like systems
Florian Ruff and Stephan Pfahl
Weather Clim. Dynam., 4, 427–447, https://doi.org/10.5194/wcd-4-427-2023, https://doi.org/10.5194/wcd-4-427-2023, 2023
Short summary
Short summary
In this study, we analyse the generic atmospheric processes of very extreme, 100-year precipitation events in large central European river catchments and the corresponding differences to less extreme events, based on a large time series (~1200 years) of simulated but realistic daily precipitation events from the ECMWF. Depending on the catchment, either dynamical mechanisms or thermodynamic conditions or a combination of both distinguish 100-year events from less extreme precipitation events.
Seraphine Hauser, Franziska Teubler, Michael Riemer, Peter Knippertz, and Christian M. Grams
Weather Clim. Dynam., 4, 399–425, https://doi.org/10.5194/wcd-4-399-2023, https://doi.org/10.5194/wcd-4-399-2023, 2023
Short summary
Short summary
Blocking describes a flow configuration in the midlatitudes where stationary high-pressure systems block the propagation of weather systems. This study combines three individual perspectives that capture the dynamics and importance of various processes in the formation of a major blocking in 2016 from a weather regime perspective. In future work, this framework will enable a holistic view of the dynamics and the role of moist processes in different life cycle stages of blocked weather regimes.
Charles G. Gertler, Paul A. O'Gorman, and Stephan Pfahl
Weather Clim. Dynam., 4, 361–379, https://doi.org/10.5194/wcd-4-361-2023, https://doi.org/10.5194/wcd-4-361-2023, 2023
Short summary
Short summary
The relationship between the time-mean state of the atmosphere and aspects of atmospheric circulation drives general understanding of the atmospheric circulation. Here, we present new techniques to calculate local properties of the time-mean atmosphere and relate those properties to aspects of extratropical circulation with important implications for weather. This relationship should help connect changes to the atmosphere, such as under global warming, to changes in midlatitude weather.
Colin Manning, Martin Widmann, Douglas Maraun, Anne F. Van Loon, and Emanuele Bevacqua
Weather Clim. Dynam., 4, 309–329, https://doi.org/10.5194/wcd-4-309-2023, https://doi.org/10.5194/wcd-4-309-2023, 2023
Short summary
Short summary
Climate models differ in their representation of dry spells and high temperatures, linked to errors in the simulation of persistent large-scale anticyclones. Models that simulate more persistent anticyclones simulate longer and hotter dry spells, and vice versa. This information is important to consider when assessing the likelihood of such events in current and future climate simulations so that we can assess the plausibility of their future projections.
Franziska Teubler, Michael Riemer, Christopher Polster, Christian M. Grams, Seraphine Hauser, and Volkmar Wirth
Weather Clim. Dynam., 4, 265–285, https://doi.org/10.5194/wcd-4-265-2023, https://doi.org/10.5194/wcd-4-265-2023, 2023
Short summary
Short summary
Weather regimes govern an important part of the sub-seasonal variability of the mid-latitude circulation. The year-round dynamics of blocked regimes in the Atlantic European region are investigated in over 40 years of data. We show that the dynamics between the regimes are on average very similar. Within the regimes, the main variability – starting from the characteristics of dynamical processes alone – dominates and transcends the variability in season and types of transitions.
Acacia S. Pepler and Irina Rudeva
Weather Clim. Dynam., 4, 175–188, https://doi.org/10.5194/wcd-4-175-2023, https://doi.org/10.5194/wcd-4-175-2023, 2023
Short summary
Short summary
In recent decades, cold fronts have rained less often in southeast Australia, which contributes to decreasing cool season rainfall. The largest changes in front dynamics are found to the north of the area where rain changes. Wet fronts have strong westerly winds that reach much further north than dry fronts do, and these fronts are becoming less common, linked to weakening subtropical winds and changes in the Southern Hemisphere circulation.
Alexander Scherrmann, Heini Wernli, and Emmanouil Flaounas
Weather Clim. Dynam., 4, 157–173, https://doi.org/10.5194/wcd-4-157-2023, https://doi.org/10.5194/wcd-4-157-2023, 2023
Short summary
Short summary
We investigate the dynamical origin of the lower-atmospheric potential vorticity (PV; linked to the intensity of cyclones) in Mediterranean cyclones. We quantify the contribution of the cyclone and the environment by tracing PV backward in time and space and linking it to the track of the cyclone. We find that the lower-tropospheric PV is produced shortly before the cyclone's stage of highest intensity. We investigate the driving processes and use a global dataset and a process-resolving one.
Felix Jäger, Philip Rupp, and Thomas Birner
Weather Clim. Dynam., 4, 49–60, https://doi.org/10.5194/wcd-4-49-2023, https://doi.org/10.5194/wcd-4-49-2023, 2023
Short summary
Short summary
Mid-latitude weather is dominated by the growth, breaking and decay of baroclinic waves and associated jet shifts. A way to study this process is via idealised life-cycle simulations, which are often classified as LC1 (anticyclonic breaking, poleward shift) or LC2 (cyclonic breaking, equatorward shift), depending on details of the initial state. We show that all systems exhibit predominantly anticyclonic character and poleward net shifts if multiple wave modes are allowed to grow simultaneously.
Philipp Breul, Paulo Ceppi, and Theodore G. Shepherd
Weather Clim. Dynam., 4, 39–47, https://doi.org/10.5194/wcd-4-39-2023, https://doi.org/10.5194/wcd-4-39-2023, 2023
Short summary
Short summary
Accurately predicting the response of the midlatitude jet stream to climate change is very important, but models show a variety of possible scenarios. Previous work identified a relationship between climatological jet latitude and future jet shift in the southern hemispheric winter. We show that the relationship does not hold in separate sectors and propose that zonal asymmetries are the ultimate cause in the zonal mean. This questions the usefulness of the relationship.
Patrick Johannes Stoll, Rune Grand Graversen, and Gabriele Messori
Weather Clim. Dynam., 4, 1–17, https://doi.org/10.5194/wcd-4-1-2023, https://doi.org/10.5194/wcd-4-1-2023, 2023
Short summary
Short summary
The atmosphere is in motion and hereby transporting warm, cold, moist, and dry air to different climate zones. In this study, we investigate how this transport of energy organises in different manners. Outside the tropics, atmospheric waves of sizes between 2000 and 8000 km, which we perceive as cyclones from the surface, transport most of the energy and moisture poleward. In the winter, large-scale weather situations become very important for transporting energy into the polar regions.
Deborah Morgenstern, Isabell Stucke, Georg J. Mayr, Achim Zeileis, and Thorsten Simon
EGUsphere, https://doi.org/10.5194/egusphere-2022-1453, https://doi.org/10.5194/egusphere-2022-1453, 2023
Short summary
Short summary
Thunderstorms in Europe are described by two types. Mass-field thunderstorms that occur mostly in summer, over the mainland, and under similar meteorological conditions and wind-field thunderstorms that occur mostly in winter, over the sea, and under more diverse meteorological conditions. Our descriptions are independent of static thresholds and help to understand why thunderstorms in unfavorable seasons for lightning are a particular risk for tall infrastructure such as wind turbines.
Lisa Schielicke and Stephan Pfahl
Weather Clim. Dynam., 3, 1439–1459, https://doi.org/10.5194/wcd-3-1439-2022, https://doi.org/10.5194/wcd-3-1439-2022, 2022
Short summary
Short summary
Projected future heatwaves in many European regions will be even warmer than the mean increase in summer temperature suggests. To identify the underlying thermodynamic and dynamic processes, we compare Lagrangian backward trajectories of airstreams associated with heatwaves in two time slices (1991–2000 and 2091–2100) in a large single-model ensemble (CEMS-LE). We find stronger future descent associated with adiabatic warming in some regions and increased future diabatic heating in most regions.
Iana Strigunova, Richard Blender, Frank Lunkeit, and Nedjeljka Žagar
Weather Clim. Dynam., 3, 1399–1414, https://doi.org/10.5194/wcd-3-1399-2022, https://doi.org/10.5194/wcd-3-1399-2022, 2022
Short summary
Short summary
We show that the Eurasian heat waves (HWs) have signatures in the global circulation. We present changes in the probability density functions (PDFs) of energy anomalies in the zonal-mean state and in the Rossby waves at different zonal scales in relation to the changes in intramonthly variability. The skewness of the PDF of planetary-scale Rossby waves is shown to increase during HWs, while their intramonthly variability is reduced, a process referred to as blocking.
Anubhav Choudhary and Aiko Voigt
Weather Clim. Dynam., 3, 1199–1214, https://doi.org/10.5194/wcd-3-1199-2022, https://doi.org/10.5194/wcd-3-1199-2022, 2022
Short summary
Short summary
The warm conveyor belt (WCB), which is a stream of coherently rising air parcels, is an important feature of extratropical cyclones. This work presents the impact of model grid spacing on simulation of cloud diabatic processes in the WCB of a North Atlantic cyclone. We find that the refinement of the model grid systematically enhances the dynamical properties and heat releasing processes within the WCB. However, this pattern does not have a strong impact on the strength of associated cyclones.
S. Mubashshir Ali, Matthias Röthlisberger, Tess Parker, Kai Kornhuber, and Olivia Martius
Weather Clim. Dynam., 3, 1139–1156, https://doi.org/10.5194/wcd-3-1139-2022, https://doi.org/10.5194/wcd-3-1139-2022, 2022
Short summary
Short summary
Persistent weather can lead to extreme weather conditions. One such atmospheric flow pattern, termed recurrent Rossby wave packets (RRWPs), has been shown to increase persistent weather in the Northern Hemisphere. Here, we show that RRWPs are also an important feature in the Southern Hemisphere. We evaluate the role of RRWPs during south-eastern Australian heatwaves and find that they help to persist the heatwaves by forming upper-level high-pressure systems over south-eastern Australia.
Lea Eisenstein, Benedikt Schulz, Ghulam A. Qadir, Joaquim G. Pinto, and Peter Knippertz
Weather Clim. Dynam., 3, 1157–1182, https://doi.org/10.5194/wcd-3-1157-2022, https://doi.org/10.5194/wcd-3-1157-2022, 2022
Short summary
Short summary
Mesoscale high-wind features within extratropical cyclones can cause immense damage. Here, we present RAMEFI, a novel approach to objectively identify the wind features based on a probabilistic random forest. RAMEFI enables a wide range of applications such as probabilistic predictions for the occurrence or a multi-decadal climatology of these features, which will be the focus of Part 2 of the study, with the goal of improving wind and, specifically, wind gust forecasts in the long run.
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
Short summary
Short summary
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.
Valerio Lembo, Federico Fabiano, Vera Melinda Galfi, Rune Grand Graversen, Valerio Lucarini, and Gabriele Messori
Weather Clim. Dynam., 3, 1037–1062, https://doi.org/10.5194/wcd-3-1037-2022, https://doi.org/10.5194/wcd-3-1037-2022, 2022
Short summary
Short summary
Eddies in mid-latitudes characterize the exchange of heat between the tropics and the poles. This exchange is largely uneven, with a few extreme events bearing most of the heat transported across latitudes in a season. It is thus important to understand what the dynamical mechanisms are behind these events. Here, we identify recurrent weather regime patterns associated with extreme transports, and we identify scales of mid-latitudinal eddies that are mostly responsible for the transport.
Fei Luo, Frank Selten, Kathrin Wehrli, Kai Kornhuber, Philippe Le Sager, Wilhelm May, Thomas Reerink, Sonia I. Seneviratne, Hideo Shiogama, Daisuke Tokuda, Hyungjun Kim, and Dim Coumou
Weather Clim. Dynam., 3, 905–935, https://doi.org/10.5194/wcd-3-905-2022, https://doi.org/10.5194/wcd-3-905-2022, 2022
Short summary
Short summary
Recent studies have identified the weather systems in observational data, where wave patterns with high-magnitude values that circle around the whole globe in either wavenumber 5 or wavenumber 7 are responsible for the extreme events. In conclusion, we find that the climate models are able to reproduce the large-scale atmospheric circulation patterns as well as their associated surface variables such as temperature, precipitation, and sea level pressure.
Meryl Wimmer, Gwendal Rivière, Philippe Arbogast, Jean-Marcel Piriou, Julien Delanoë, Carole Labadie, Quitterie Cazenave, and Jacques Pelon
Weather Clim. Dynam., 3, 863–882, https://doi.org/10.5194/wcd-3-863-2022, https://doi.org/10.5194/wcd-3-863-2022, 2022
Short summary
Short summary
The effect of deep convection representation on the jet stream above the cold front of an extratropical cyclone is investigated in the global numerical weather prediction model ARPEGE. Two simulations using different deep convection schemes are compared with (re)analysis datasets and NAWDEX airborne observations. A deeper jet stream is observed with the less active scheme. The diabatic origin of this difference is interpreted by backward Lagrangian trajectories and potential vorticity budgets.
Matthias Röthlisberger, Barbara Scherrer, Andries Jan de Vries, and Raphael Portmann
Weather Clim. Dynam., 3, 733–754, https://doi.org/10.5194/wcd-3-733-2022, https://doi.org/10.5194/wcd-3-733-2022, 2022
Short summary
Short summary
We examine the palette of synoptic storylines accompanying unusually long wet spells in Europe. Thereby, we identify a hitherto not documented mechanism for generating long wet spells which involves recurrent Rossby wave breaking and subsequent cutoff replenishment. Understanding the synoptic processes behind long wet spells is relevant in light of projected changes in wet spell characteristics as it is a prerequisite for evaluating climate models with regard to such events.
Paolo Davini, Federico Fabiano, and Irina Sandu
Weather Clim. Dynam., 3, 535–553, https://doi.org/10.5194/wcd-3-535-2022, https://doi.org/10.5194/wcd-3-535-2022, 2022
Short summary
Short summary
In climate models, improvements obtained in the winter mid-latitude circulation following horizontal resolution increase are mainly caused by the more detailed representation of the mean orography. A high-resolution climate model with low-resolution orography might underperform compared to a low-resolution model with low-resolution orography. The absence of proper model tuning at high resolution is considered the potential reason behind such lack of improvements.
Joshua Dorrington, Kristian Strommen, and Federico Fabiano
Weather Clim. Dynam., 3, 505–533, https://doi.org/10.5194/wcd-3-505-2022, https://doi.org/10.5194/wcd-3-505-2022, 2022
Short summary
Short summary
We investigate how well current state-of-the-art climate models reproduce the wintertime weather of the North Atlantic and western Europe by studying how well different "regimes" of weather are captured. Historically, models have struggled to capture these regimes, making it hard to predict future changes in wintertime extreme weather. We show models can capture regimes if the right method is used, but they show biases, partially as a result of biases in jet speed and eddy strength.
Jacopo Riboldi, Efi Rousi, Fabio D'Andrea, Gwendal Rivière, and François Lott
Weather Clim. Dynam., 3, 449–469, https://doi.org/10.5194/wcd-3-449-2022, https://doi.org/10.5194/wcd-3-449-2022, 2022
Short summary
Short summary
A revisited space and time spectral decomposition allows us to determine which harmonics dominate the upper-tropospheric flow evolution over a given time period as well as their propagation. This approach is used to identify Rossby wave patterns with a circumglobal extent, affecting weather evolution over different Northern Hemisphere regions. The results cast light on the processes originating and supporting these wave patterns, advocating at the same time for the usefulness of the technique.
Philipp Zschenderlein and Heini Wernli
Weather Clim. Dynam., 3, 391–411, https://doi.org/10.5194/wcd-3-391-2022, https://doi.org/10.5194/wcd-3-391-2022, 2022
Short summary
Short summary
Precipitation and temperature are two of the most important variables describing our weather and climate. The relationship between these variables has been studied extensively; however, the role of specific weather systems in shaping this relationship has not been analysed yet. We therefore analyse whether intense precipitation occurs on warmer or on colder days and identify the relevant weather systems. In general, weather systems strongly influence this relationship, especially in winter.
Deborah Morgenstern, Isabell Stucke, Thorsten Simon, Georg J. Mayr, and Achim Zeileis
Weather Clim. Dynam., 3, 361–375, https://doi.org/10.5194/wcd-3-361-2022, https://doi.org/10.5194/wcd-3-361-2022, 2022
Short summary
Short summary
Wintertime lightning in central Europe is rare but has a large damage potential for tall structures such as wind turbines. We use a data-driven approach to explain why it even occurs when the meteorological processes causing thunderstorms in summer are absent. In summer, with strong solar input, thunderclouds have a large vertical extent, whereas in winter, thunderclouds are shallower in the vertical but tilted and elongated in the horizontal by strong winds that increase with altitude.
Matthew D. K. Priestley and Jennifer L. Catto
Weather Clim. Dynam., 3, 337–360, https://doi.org/10.5194/wcd-3-337-2022, https://doi.org/10.5194/wcd-3-337-2022, 2022
Short summary
Short summary
We use the newest set of climate model experiments from CMIP6 to investigate changes to mid-latitude storm tracks and cyclones from global warming. The overall number of cyclones will decrease. However in winter there will be more of the most intense cyclones, and these intense cyclones are likely to be stronger. Cyclone wind speeds will increase in winter, and as a result the area of strongest wind speeds will increase. By 2100 the area of strong wind speeds may increase by over 30 %.
Lisa-Ann Kautz, Olivia Martius, Stephan Pfahl, Joaquim G. Pinto, Alexandre M. Ramos, Pedro M. Sousa, and Tim Woollings
Weather Clim. Dynam., 3, 305–336, https://doi.org/10.5194/wcd-3-305-2022, https://doi.org/10.5194/wcd-3-305-2022, 2022
Short summary
Short summary
Atmospheric blocking is associated with stationary, self-sustaining and long-lasting high-pressure systems. They can cause or at least influence surface weather extremes, such as heat waves, cold spells, heavy precipitation events, droughts or wind extremes. The location of the blocking determines where and what type of extreme event will occur. These relationships are also important for weather prediction and may change due to global warming.
Manuel Saigger and Alexander Gohm
Weather Clim. Dynam., 3, 279–303, https://doi.org/10.5194/wcd-3-279-2022, https://doi.org/10.5194/wcd-3-279-2022, 2022
Short summary
Short summary
In this work a special form of a foehn wind in an Alpine valley with a large-scale northwesterly flow is investigated. The study clarifies the origin of the air mass and the mechanisms by which this air enters the valley. A trajectory analysis shows that the location where the main airstream passes the crest line is more suitable for a foehn classification than the local or large-scale wind direction. Mountain waves and a lee rotor were crucial for importing air into the valley.
Antoine Blanc, Juliette Blanchet, and Jean-Dominique Creutin
Weather Clim. Dynam., 3, 231–250, https://doi.org/10.5194/wcd-3-231-2022, https://doi.org/10.5194/wcd-3-231-2022, 2022
Short summary
Short summary
Precipitation variability and extremes in the northern French Alps are governed by the atmospheric circulation over western Europe. In this work, we study the past evolution of western Europe large-scale circulation using atmospheric descriptors. We show some discrepancies in the trends obtained from different reanalyses before 1950. After 1950, we find trends in Mediterranean circulations that appear to be linked with trends in seasonal and extreme precipitation in the northern French Alps.
Paolo Ghinassi, Federico Fabiano, and Susanna Corti
Weather Clim. Dynam., 3, 209–230, https://doi.org/10.5194/wcd-3-209-2022, https://doi.org/10.5194/wcd-3-209-2022, 2022
Short summary
Short summary
In this work we examine the ability of global climate models in representing the atmospheric circulation in the upper troposphere, focusing on the eventual benefits of an increased horizontal resolution. Our results confirm that a higher horizontal resolution has a positive impact, especially in those models in which the resolution is increased in both the atmosphere and the ocean, whereas when the resolution is increased only in the atmosphere no substantial improvements are found.
Emmanouil Flaounas, Silvio Davolio, Shira Raveh-Rubin, Florian Pantillon, Mario Marcello Miglietta, Miguel Angel Gaertner, Maria Hatzaki, Victor Homar, Samira Khodayar, Gerasimos Korres, Vassiliki Kotroni, Jonilda Kushta, Marco Reale, and Didier Ricard
Weather Clim. Dynam., 3, 173–208, https://doi.org/10.5194/wcd-3-173-2022, https://doi.org/10.5194/wcd-3-173-2022, 2022
Short summary
Short summary
This is a collective effort to describe the state of the art in Mediterranean cyclone dynamics, climatology, prediction (weather and climate scales) and impacts. More than that, the paper focuses on the future directions of research that would advance the broader field of Mediterranean cyclones as a whole. Thereby, we propose interdisciplinary cooperation and additional modelling and forecasting strategies, and we highlight the need for new impact-oriented approaches to climate prediction.
Stefan Niebler, Annette Miltenberger, Bertil Schmidt, and Peter Spichtinger
Weather Clim. Dynam., 3, 113–137, https://doi.org/10.5194/wcd-3-113-2022, https://doi.org/10.5194/wcd-3-113-2022, 2022
Short summary
Short summary
We use machine learning to create a network that detects and classifies four types of synoptic-scale weather fronts from ERA5 atmospheric reanalysis data. We present an application of our method, showing its use case in a scientific context. Additionally, our results show that multiple sources of training data are necessary to perform well on different regions, implying differences within those regions. Qualitative evaluation shows that the results are physically plausible.
Hélène Barras, Olivia Martius, Luca Nisi, Katharina Schroeer, Alessandro Hering, and Urs Germann
Weather Clim. Dynam., 2, 1167–1185, https://doi.org/10.5194/wcd-2-1167-2021, https://doi.org/10.5194/wcd-2-1167-2021, 2021
Short summary
Short summary
In Switzerland hail may occur several days in a row. Such multi-day hail events may cause significant damage, and understanding and forecasting these events is important. Using reanalysis data we show that weather systems over Europe move slower before and during multi-day hail events compared to single hail days. Surface temperatures are typically warmer and the air more humid over Switzerland and winds are slower on multi-day hail clusters. These results may be used for hail forecasting.
Terhi K. Laurila, Hilppa Gregow, Joona Cornér, and Victoria A. Sinclair
Weather Clim. Dynam., 2, 1111–1130, https://doi.org/10.5194/wcd-2-1111-2021, https://doi.org/10.5194/wcd-2-1111-2021, 2021
Short summary
Short summary
We create a climatology of mid-latitude cyclones and windstorms in northern Europe and investigate how sensitive the minimum pressure and maximum gust of windstorms are to four precursors. Windstorms are more common in the cold season than the warm season, whereas the number of mid-latitude cyclones has no annual cycle. The low-level temperature gradient has the strongest impact of all considered precursors on the intensity of windstorms in terms of both the minimum pressure and maximum gust.
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
Short summary
Short summary
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.
Gwendal Rivière, Meryl Wimmer, Philippe Arbogast, Jean-Marcel Piriou, Julien Delanoë, Carole Labadie, Quitterie Cazenave, and Jacques Pelon
Weather Clim. Dynam., 2, 1011–1031, https://doi.org/10.5194/wcd-2-1011-2021, https://doi.org/10.5194/wcd-2-1011-2021, 2021
Short summary
Short summary
Inacurracies in representing processes occurring at spatial scales smaller than the grid scales of the weather forecast models are important sources of forecast errors. This is the case of deep convection representation in models with 10 km grid spacing. We performed simulations of a real extratropical cyclone using a model with different representations of deep convection. These forecasts lead to different behaviors in the ascending air masses of the cyclone and the jet stream aloft.
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
Short summary
Short summary
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.
Leonidas Tsopouridis, Thomas Spengler, and Clemens Spensberger
Weather Clim. Dynam., 2, 953–970, https://doi.org/10.5194/wcd-2-953-2021, https://doi.org/10.5194/wcd-2-953-2021, 2021
Short summary
Short summary
Comparing simulations with realistic and smoothed SSTs, we find that the intensification of individual cyclones in the Gulf Stream and Kuroshio regions is only marginally affected by reducing the SST gradient. In contrast, we observe a reduced cyclone activity and a shift in storm tracks. Considering differences of the variables occurring within/outside of a radius of any cyclone, we find cyclones to play only a secondary role in explaining the mean states differences among the SST experiments.
Carola Detring, Annette Müller, Lisa Schielicke, Peter Névir, and Henning W. Rust
Weather Clim. Dynam., 2, 927–952, https://doi.org/10.5194/wcd-2-927-2021, https://doi.org/10.5194/wcd-2-927-2021, 2021
Short summary
Short summary
Stationary, long-lasting blocked weather patterns can lead to extreme conditions. Within this study the temporal evolution of the occurrence probability is analyzed, and the onset, decay and transition probabilities of blocking within the past 30 years are modeled. Using Markov models combined with logistic regression, we found large changes in summer, where the probability of transitions to so-called Omega blocks increases strongly, while the unblocked state becomes less probable.
Ayako Yamamoto, Masami Nonaka, Patrick Martineau, Akira Yamazaki, Young-Oh Kwon, Hisashi Nakamura, and Bunmei Taguchi
Weather Clim. Dynam., 2, 819–840, https://doi.org/10.5194/wcd-2-819-2021, https://doi.org/10.5194/wcd-2-819-2021, 2021
Short summary
Short summary
While the key role of moist processes in blocking has recently been highlighted, their moisture sources remain unknown. Here, we investigate moisture sources for wintertime Euro-Atlantic blocks using a Lagrangian method. We show that the Gulf Stream, Kuroshio, and their extensions, along with the northeast of Hawaii, act as the primary moisture sources and springboards for particle ascent. We find that the evolution of the particle properties is sensitive to the moisture sources.
Erica Madonna, David S. Battisti, Camille Li, and Rachel H. White
Weather Clim. Dynam., 2, 777–794, https://doi.org/10.5194/wcd-2-777-2021, https://doi.org/10.5194/wcd-2-777-2021, 2021
Short summary
Short summary
The amount of precipitation over Europe varies substantially from year to year, with impacts on crop yields and energy production. In this study, we show that it is possible to infer much of the winter precipitation and temperature signal over Europe by knowing only the frequency of occurrence of certain atmospheric circulation patterns. The results highlight the importance of (daily) weather for understanding and interpreting seasonal signals.
Jacob W. Maddison, Marta Abalos, David Barriopedro, Ricardo García-Herrera, Jose M. Garrido-Perez, and Carlos Ordóñez
Weather Clim. Dynam., 2, 675–694, https://doi.org/10.5194/wcd-2-675-2021, https://doi.org/10.5194/wcd-2-675-2021, 2021
Short summary
Short summary
Air stagnation occurs when an air mass becomes settled over a region and precipitation is suppressed. Pollutant levels can rise during stagnation. The synoptic- to large-scale influence on European air stagnation and pollution is explored here. We show that around 60 % of the monthly variability in air stagnation and pollutants can be explained by dynamical indices describing the atmospheric circulation. The weather systems most related to stagnation are different for regions across Europe.
Kristine Flacké Haualand and Thomas Spengler
Weather Clim. Dynam., 2, 695–712, https://doi.org/10.5194/wcd-2-695-2021, https://doi.org/10.5194/wcd-2-695-2021, 2021
Short summary
Short summary
Given the recent focus on the influence of upper tropospheric structure in wind and temperature on midlatitude weather, we use an idealised model to investigate how structural modifications impact cyclone development. We find that cyclone intensification is less sensitive to these modifications than to changes in the amount of cloud condensation, suggesting that an accurate representation of the upper-level troposphere is less important for midlatitude weather than previously anticipated.
Thorsten Kaluza, Daniel Kunkel, and Peter Hoor
Weather Clim. Dynam., 2, 631–651, https://doi.org/10.5194/wcd-2-631-2021, https://doi.org/10.5194/wcd-2-631-2021, 2021
Short summary
Short summary
We present a 10-year analysis on the occurrence of strong wind shear in the Northern Hemisphere, focusing on the region around the transport barrier that separates the first two layers of the atmosphere. The major result of our analysis is that strong wind shear above a certain threshold occurs frequently and nearly exclusively in this region, which, as an indicator for turbulent mixing, might have major implications concerning the separation efficiency of the transport barrier.
Carl Thomas, Apostolos Voulgarakis, Gerald Lim, Joanna Haigh, and Peer Nowack
Weather Clim. Dynam., 2, 581–608, https://doi.org/10.5194/wcd-2-581-2021, https://doi.org/10.5194/wcd-2-581-2021, 2021
Short summary
Short summary
Atmospheric blocking events are complex large-scale weather patterns which block the path of the jet stream. They are associated with heat waves in summer and cold snaps in winter. Blocking is poorly understood, and the effect of climate change is not clear. Here, we present a new method to study blocking using unsupervised machine learning. We show that this method performs better than previous methods used. These results show the potential for unsupervised learning in atmospheric science.
Franziska Teubler and Michael Riemer
Weather Clim. Dynam., 2, 535–559, https://doi.org/10.5194/wcd-2-535-2021, https://doi.org/10.5194/wcd-2-535-2021, 2021
Short summary
Short summary
Rossby wave packets impact all aspects of midlatitude weather systems, from their climatological distribution to predictability. Case studies suggest an important role of latent heat release in clouds. We investigate thousands of wave packets with a novel diagnostic. We demonstrate that, on average, the impact of moist processes is substantially different between troughs and ridges and that dry conceptual models of wave packet dynamics should be extended.
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
Short summary
Short summary
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.
Patrick Martineau, Hisashi Nakamura, and Yu Kosaka
Weather Clim. Dynam., 2, 395–412, https://doi.org/10.5194/wcd-2-395-2021, https://doi.org/10.5194/wcd-2-395-2021, 2021
Short summary
Short summary
To better understand the factors that impact the weather in North America, this study explores the influence of the El Niño–Southern Oscillation on wintertime surface air temperature variability using reanalysis data. Results show that La Niña enhances subseasonal variability over western North America by amplifying the baroclinic conversion of energy from the winter-mean circulation to subseasonal eddies. Changes in the structural properties of eddies are crucial for this amplification.
Emmanouil Flaounas, Suzanne L. Gray, and Franziska Teubler
Weather Clim. Dynam., 2, 255–279, https://doi.org/10.5194/wcd-2-255-2021, https://doi.org/10.5194/wcd-2-255-2021, 2021
Short summary
Short summary
In this study, we quantify the relative contribution of different atmospheric processes to the development of 100 intense Mediterranean cyclones and show that both upper tropospheric systems and diabatic processes contribute to cyclone development. However, these contributions are complex and present high variability among the cases. For this reason, we analyse several exemplary cases in more detail, including 10 systems that have been identified in the past as tropical-like cyclones.
Cited articles
Aebischer, U. and Schär C.: Low-level potential vorticity and
cyclogenesis to the lee of the Alps, J. Atmos. Sci., 55, 186–207,
https://doi.org/10.1175/1520-0469(1998)055<0186:LLPVAC>2.0.CO;2, 1998.
Berthou, S., Mailler, S., Drobinski, P., Arsouze, T., Bastin, S.,
Béranger, K., and Lebeaupin-Brossier, C.: Prior history of mistral and
tramontane winds modulates heavy precipitation events in southern
France, Tellus A, 66, 24064, https://doi.org/10.3402/tellusa.v66.24064,
2014.
Berthou, S., Mailler, S., Drobinski, P., Arsouze, T., Bastin, S.
Béranger, K., and Brossier, C. L.: Lagged effects of the Mistral wind on
heavy precipitation through ocean-atmosphere coupling in the region of
Valencia (Spain), Clim. Dynam., 51, 969–983,
https://doi.org/10.1007/s00382-016-3153-0, 2018.
Bouin, M.-N. and Lebeaupin Brossier, C.: Surface processes in the 7 November 2014 medicane from air–sea coupled high-resolution numerical modelling, Atmos. Chem. Phys., 20, 6861–6881, https://doi.org/10.5194/acp-20-6861-2020, 2020.
Burlando, M.: The synoptic-scale surface wind climate regimes of the
Mediterranean Sea according to the cluster analysis of ERA-40 wind
fields, Theor. Appl. Climatol., 96, 69–83,
https://doi.org/10.1007/s00704-008-0033-5, 2009.
Buzzi, A. and Speranza, A.: A theory of deep cyclogenesis in the lee of the
Alps. Part II: Effects of finite topographic slope and height, J. Atmos.
Sci., 43, 2826–2837,
https://doi.org/10.1175/1520-0469(1986)043<2826:ATODCI>2.0.CO;2, 1986.
Buzzi, A. and Tibaldi, S.: Cyclogenesis in the lee of the Alps: A case study, Q. J. Roy. Meteor. Soc., 104, 271–287, https://doi.org/10.1002/qj.49710444004, 1978.
Buzzi, A., D'Isidoro, M., and Davolio, S.: A case-study of an orographic
cyclone south of the Alps during the MAP SOP, Q. J. Roy. Meteor.
Soc., 129, 1795–1818, https://doi.org/10.1256/qj.02.112, 2003.
Buzzi, A., Davolio, S., and Fantini, M.: Cyclogenesis in the lee of the Alps:
a review of theories, B. Atmos. Sci. Technol., 1, 433–457,
https://doi.org/10.1007/s42865-020-00021-6, 2020.
Čampa, J. and Wernli, H.: A PV perspective on the vertical structure of
mature midlatitude cyclones in the Northern Hemisphere, J. Atmos. Sci.,
69, 725–740, https://doi.org/10.1175/JAS-D-11-050.1, 2012.
Campins, J., Genovés, A., Picornell, M. A., and Jansà, A.:
Climatology of Mediterranean cyclones using the ERA-40 dataset, Int. J.
Climatol., 31, 1596–1614, https://doi.org/10.1002/joc.2183, 2011.
Cassano, E. N., Lynch, A. H., Cassano, J. J., and Koslow, M. R.:
Classification of synoptic patterns in the western Arctic associated with
extreme events at Barrow, Alaska, USA, Clim. Res., 30, 83–97,
https://doi.org/10.3354/cr030083, 2006.
Cioni, G., Cerrai, D., and Klocke, D.: Investigating the predictability of a
Mediterranean tropical-like cyclone using a storm-resolving model, Q. J.
Roy. Meteor. Soc., 144, 1598–1610, https://doi.org/10.1002/qj.3322,
2018.
Dafis, S., Rysman, J. F., Claud, C., and Flaounas, E.: Remote sensing of deep
convection within a tropical-like cyclone over the Mediterranean Sea, Atmos.
Sci. Lett., 19, e823, https://doi.org/10.1002/asl.823, 2018.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P.,
Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P.,
Bechtold, P., Beljaars, A. C. M., van de Berg, L., Bidlot, .J, Bormann, .N,
Delsol, C., Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy, S.
B., Hersbach, H., Holm, E. V., Isaksen, L. K., allberg P. K., Ohler, M.,
Matricardi. M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J. J., Park,
B. K., Peubey, C., de Rosnay, P., Tavolato, C., Thepaut, J. N., and Vitart, F.:
The ERA-Interim reanalysis: configuration and performance of the data
assimilation system, Q. J. Roy. Meteor. Soc., 137, 553–597,
https://doi.org/10.1002/qj.828, 2011.
Drobinski, P., Flamant, C., Dusek, J., Flamant, P. H., and Pelon,
J.: Observational evidence and modelling of an internal hydraulic jump at
the atmospheric boundary-layer top during a tramontane event, Bound.-Lay. Meteorol., 98, 497–515, https://doi.org/10.1023/A:1018751311924, 2001a.
Drobinski, P., Dusek, J., and Flamant, C.: Diagnostics of hydraulic jump and
gap flow in stratified flows over topography, Bound.-Lay. Meteorol., 98,
475–495, https://doi.org/10.1023/A:1018703428762, 2001b.
Drobinski, P., Bastin, S., Guénard, V., Caccia, J. L., Dabas, A. M.,
Delville, P., Protat, A., Reitebuch, O., and Werner, C.: Summer mistral at
the exit of the Rhône valley, Q. J. Roy. Meteor. Soc., 131,
353–375, https://doi.org/10.1256/qj.04.63, 2005.
Drobinski, P., Anav, A., Lebeaupin-Brossier, C., Samson, G., Stéfanon, M.,
Bastin, S., Baklouti, M., Béranger, K., Beuvier, J., Bourdallé-Badie, R.,
Coquart, L., D'Andrea, F., de Noblet-Ducoudré, N., Diaz, F., Dutay, J. C.,
Ethe, C., Foujols, M. A., Khvorostyanov, D., Madec, G., Mancip, M., Masson, S.,
Menut, L., Palmieri, J., Polcher, J., Turquety, S., Valcke, S., and Viovy, N.: Model
of the regional coupled earth system (MORCE): application to process and
climate studies in vulnerable regions, Environ. Model Softw., 35, 1–18,
https://doi.org/10.1016/j.envsoft.2012.01.017, 2012.
Drobinski, P., Ducrocq, V., Alpert, P., Anagnostou, E., Béranger, K., Borga,
M., Braud, I., Chanzy, A., Davolio, S., Delrieu, G., Estournel, C., Boubrahmi, N.
F., Font, J., Grubisic, V., Gualdi, S., Homar, V., Ivancan-Picek, B., Kottmeier,
C., Kotroni, V., Lagouvardos, K., Lionello, P., Llasat, M., Ludwig, W., Lutoff,
C., Mariotti, A., Richard, E., Romero, R., Rotunno, R., Roussot, O., Ruin, I.,
Somot, S., Taupier-Letage, I., Tintore, J., Uijlenhoet, R., and Wernli, H.: HyMeX, a
10-year multidisciplinary program on the Mediterranean water cycle, B. Am.
Meteorol. Soc., 95, 1063–1082, https://doi.org/10.1175/BAMS-D-12-00242.1, 2014.
Drobinski, P., Alonzo, B., Basdevant, C., Cocquerez, P., Doerenbecher, A.,
Fourrié, N., and Nuret, M.: Lagrangian dynamics of the mistral during
the HyMeX SOP2, J Geophys. Res.-Atmos., 122, 1387–1402,
https://doi.org/10.1002/2016JD025530, 2017.
Drobinski, P., Bastin, S., Arsouze, T., Beranger, K., Flaounas, E., and
Stefanon, M.: North-western Mediterranean sea-breeze circulation in a
regional climate system model, Clim. Dynam., 51, 1077–1093,
https://doi.org/10.1007/s00382-017-3595-z , 2018.
ECMWF: ERA-INTERIM datasets, available at:
https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era-interim, last access: 15 July 2021.
Espinoza, J. C., Lengaigne, M., Ronchail, J., and Janicot, S.: Large-scale
circulation patterns and related rainfall in the Amazon Basin: a neuronal
networks approach, Clim. Dynam., 38, 121–140,
https://doi.org/10.1007/s00382-011-1010-8, 2012.
Ernst, J. A. and Matson, M.: A Mediterranean tropical storm?, Weather,
38, 332–337, https://doi.org/10.1002/j.1477-8696.1983.tb04818.x, 1983.
Flamant, C.: Alpine lee cyclogenesis influence on air-sea heat exchanges and
marine atmospheric boundary layer thermodynamics over the western
Mediterranean during a Tramontane/Mistral event, J. Geophys. Res.-Oceans,
108, 8057, https://doi.org/10.1029/2001JC001040, 2003.
Flaounas, E., Raveh-Rubin, S., Wernli, H., Drobinski, P., and Bastin, S.:
The dynamical structure of intense Mediterranean cyclones, Clim.
Dynam., 44, 2411–2427, https://doi.org/10.1007/s00382-014-2330-2,
2015.
Guenard, V., Drobinski, P., Caccia, J. L., Campistron, B., and Bench, B.: An
observational study of the mesoscale mistral dynamics, Bound.-Lay.
Meteorol., 115, 263–288, https://doi.org/10.1007/s10546-004-3406-z, 2005.
Guion, A., Turquety, S., Polcher, J., Pennel, R., Bastin, S., and Arsouze, T.:
Droughts and heatwaves in the Western Mediterranean: impact on vegetation
and wildfires using the coupled WRF-ORCHIDEE regional model (RegIPSL), Clim. Dynam., in review, 2021.
Huang, W., Chen, R., Wang, B., Wright, J. S., Yang, Z., and Ma, W.:
Potential vorticity regimes over East Asia during winter, J. Geophys.
Res.-Atmos., 122, 1524–1544, https://doi.org/10.1002/2016JD025893, 2017.
Jain, A. K. and Dubes, R. C.: Algorithms for clustering data, River, NJ, United States, 1988.
Jiang, Q., Smith, R. B., and Doyle, J.: The nature of the mistral:
Observations and modelling of two MAP events, Q. J. Roy. Meteor.
Soc., 129, 857–875, https://doi.org/10.1256/qj.02.21, 2003.
Johnson, N. C., Feldstein, S. B., and Tremblay, B.: The continuum of
Northern Hemisphere teleconnection patterns and a description of the NAO
shift with the use of self-organizing maps, J. Climate, 21, 6354–6371,
https://doi.org/10.1175/2008JCLI2380.1, 2008.
Kaskaoutis, D. G., Kambezidis, H. D., Nastos, P. T., and Kosmopoulos, P.
G.: Study on an intense dust storm over Greece, Atmos. Environ.,
42, 6884–6896, https://doi.org/10.1016/j.atmosenv.2008.05.017, 2008.
Kiviluoto, K.: Topology preservation in self-organizing maps. Proceedings of
International Conference on Neural Networks (ICNN'96), 1, 294–299,
https://doi.org/10.1109/ICNN.1996.548907, 1996.
Lebeaupin-Brossier, C. and Drobinski, P.: Numerical high-resolution air-sea
coupling over the GOL during two tramontane/mistral events, J. Geophys.
Res.-Atmos., 114, D10110, https://doi.org/10.1029/2008JD011601, 2009.
Lebeaupin-Brossier, C., Drobinski, P., Béranger, K., Bastin, S., and
Orain, F.: Ocean memory effect on the dynamics of coastal heavy
precipitation preceded by a mistral event in the northwestern
Mediterranean, Q. J. Roy. Meteor. Soc., 139, 1583–1597,
https://doi.org/10.1002/qj.2049, 2013.
Li, L., Bozec, A., Somot, S., Béranger, K., Bouruet-Aubertot, P.,
Sevault, F., and Crepon, M.: Regional atmospheric, marine processes and
climate modelling, Developments in Earth and Environmental Sciences,
4, 373–397, https://doi.org/10.1016/S1571-9197(06)80010-8,
2006.
Liu, Y., Weisberg, R. H., and J. I. Mwasiagi (Eds.):. A review of
self-organizing map applications in meteorology and
oceanography, Self-Organizing Maps: Applications and Novel Algorithm Design,
InTech publications, Rijeka, Croatia, 2011.
Mattocks, C. and Bleck, R.: Jet streak dynamics and geostrophic adjustment
processes during the initial stages of lee cyclogenesis, Mon. Weather
Rev., 114, 2033–2056,
https://doi.org/10.1175/1520-0493(1986)114<2033:JSDAGA>2.0.CO;2, 1986.
Millot, C.: Wind induced upwellings in the GOL, Oceanol. Acta, 2,
261–274, https://archimer.ifremer.fr/doc/00122/23335/ (last access: 15 July 2021), 1979.
Moscatello, A., Marcello Miglietta, M., and Rotunno, R.: Observational
analysis of a Mediterranean “hurricane” over south-eastern Italy, Weather,
63, 306, https://doi.org/10.1002/wea.231,
2008.
Obermann, A., Bastin, S., Belamari, S., Conte, D., Gaertner, M. A., Li, L.,
and Ahrens, B.: Mistral and Tramontane wind speed and wind direction
patterns in regional climate simulations, Clim. Dynam., 51, 1059–1076,
https://doi.org/10.1007/s00382-016-3053-3, 2018.
Plačko-Vršnak, D., Mahović, N. S., and Drvar, D.: Case study on
Genoa cyclone with mistral 13–15 February 2005, available at:
http://www.umr-cnrm.fr/icam2007/ICAM2007/extended/manuscript_180.pdf (last access: 15 July 2021), 2005.
Pytharoulis, I., Craig, G. C., and Ballard, S. P.: Study of the Hurricane-like
Mediterranean Cyclone of January 1995, Phys. Chem. Earth. Elsevier B.V., 24, 627–632,
https://doi.org/10.1016/S1464-1909(99)00056-8, 1999.
Rainaud, R, Lebeaupin-Brossier C, Ducrocq V, Giordani H, Nuret M, Fourrié
N, Bouin M-N, Taupier-Letage I, and Legain D.: Characterisation of air–sea
exchanges over the Western Mediterranean Sea during the HyMeX SOP1 using the
AROME-WMED model, Q. J. Roy. Meteor. Soc., 142, 173–187,
https://doi.org/10.1002/qj.2480, 2016.
Rainaud, R., Lebeaupin-Brossier, C. L., Ducrocq, V., and Giordani, H.:
High-resolution air–sea coupling impact on two heavy precipitation events
in the Western Mediterranean, Q. J. Roy. Meteor. Soc., 143,
2448–2462, https://doi.org/10.1002/qj.3098, 2017.
Raveh-Rubin, S. and Flaounas, E.: A dynamical link between deep Atlantic
extratropical cyclones and intense Mediterranean cyclones, Atmos. Sci.
Lett., 18, 215–221,
https://doi.org/10.1002/asl.745, 2017.
Raveh-Rubin, S. and Wernli, H.: Large-scale wind and precipitation extremes
in the Mediterranean: a climatological analysis for 1979–2012, Q. J. Roy.
Meteor. Soc., 141, 2404–2417, https://doi.org/10.1002/qj.2531, 2015.
Raveh-Rubin, S. and Wernli, H.: Large-scale wind and precipitation extremes
in the Mediterranean: dynamical aspects of five selected cyclone events, Q.
J. Roy. Meteor. Soc., 142, 3097–3114,
https://doi.org/10.1002/qj.2891, 2016.
Ricchi, A., Miglietta, M. M., Barbariol, F., Benetazzo, A., Bergamasco, A.,
Bonaldo, D., Cassardo, C., Falcieri, F. M., Modugno, G., Russo, A., Sclavo,
M., and Carniel, S.: Sensitivity of a Mediterranean Tropical-Like Cyclone to
Different Model Configurations and Coupling Strategies, Atmosphere-Basel, 8, 92, https://doi.org/10.3390/atmos8050092,
2017.
Rossa, A. M., Wernli, H., and Davies, H. C.: Growth and decay of an
extra-tropical cyclone's PV-tower, Meteorol. Atmos. Phys., 73, 139–156,
https://doi.org/10.1007/s007030050070, 2000.
Ruffault, J., Moron, V., Trigo, R. M., and Curt, T.: Daily synoptic
conditions associated with large fire occurrence in Mediterranean France:
evidence for a wind-driven fire regime, Int. J. Climatol., 37, 524–533,
https://doi.org/10.1002/joc.4680, 2017.
Ruti, P., Somot, S., Giorgi, F., Dubois, C., Flaounas, E., Obermann, A.,
Dell'Aquila, A., Pisacane, G., Harzallah, A., Lombardi, E., Ahrens, B., Akhtar,
N., Alias, A., Arsouze, T., Raznar, R., Bastin, S., Bartholy, J., Béranger,
K., Beuvier, J., Bouffies-Cloche, S., Brauch, J., Cabos, W., Calmanti, S., Calvet, J., Carillo, A., Conte, D., Coppola, E., Djurdjevic, V., Drobinski, P., Elizalde, A., Gaertner, M., Galan, P., Gallardo, C., Gualdi, S., Goncalves, M., Jorba, O.,
Jorda, G., Lheveder, B., Lebeaupin-Brossier, C., Li, L., Liguori, G., Lionello,
P., Macias-Moy, D., Onol, B., Rajkovic, B., Ramage, K., Sevault, F., Sannino, G.,
Struglia, M., Sanna, A., Torma, C., and Vervatis, V.: MED-CORDEX initiative for
Mediterranean Climate studies, B. Am. Meteor. Soc., 97, 1187–1208,
https://doi.org/10.1175/BAMS-D-14-00176.1, 2016.
Schott, F., Visbeck, M., Send, U., Fischer, J., Stramma, L., and Desaubies,
Y.: Observations of deep convection in the GOL, northern Mediterranean,
during the winter of 1991/92, J. Phys. Oceanogr., 26, 505–524,
https://doi.org/10.1175/1520-0485(1996)026<0505:OODCIT>2.0.CO;2, 1996.
Scorer, R. S.: Mountain-gap winds; a study of surface wind at Gibraltar, Q.
J. Roy. Meteor. Soc., 78, 53–61,
https://doi.org/10.1002/qj.49707833507, 1952.
Sheridan, S. C. and Lee, C. C.: The self-organizing map in synoptic
climatological research, Prog. Phys. Geog., 35, 109–119,
https://doi.org/10.1177/0309133310397582, 2011.
Smith, R. B.: Further development of a theory of lee cyclogenesis, J.
Atmos. Sci., 43, 1582–1602, 1986.
Speranza, A., Buzzi, A., Trevisan, A., and Malguzzi, P.: A theory of deep
cyclogenesis in the lee of the Alps. Part I: Modifications of baroclinic
instability by localized topography, J. Atmos. Sci., 42, 1521–1535,
https://doi.org/10.1175/1520-0469(1985)042<1521:ATODCI>2.0.CO;2, 1985.
Tafferner, A.: Lee cyclogenesis resulting from the combined outbreak of cold
air and potential vorticity against the Alps, Meteorol. Atmos. Phys., 43,
31–47,
https://doi.org/10.1007/BF01028107, 1990.
Thorncroft, C. D., Hoskins, B. J., and McIntyre, M. E.: Two paradigms of
baroclinic-wave life-cycle behaviour, Q. J. Roy. Meteor. Soc., 119,
17–55, https://doi.org/10.1002/qj.49711950903, 1993.
Tous, M. and Romero, R.: Meteorological environments associated with
medicane development, Int. J. Climatol., 33, 1–14,
https://doi.org/10.1002/joc.3428, 2013.
Tsidulko, M. and Alpert, P.: Synergism of upper-level potential vorticity
and mountains in Genoa lee cyclogenesis–a numerical study, Meteorol. Atmos.
Phys., 78, 261–285, https://doi.org/10.1007/s703-001-8178-8, 2001.
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.
Wernli, H. and Sprenger, M.: Identification and ERA-15 climatology of
potential vorticity streamers and cutoffs near the extratropical
tropopause, J. Atmos. Sci., 64, 1569–1586,
https://doi.org/10.1175/JAS3912.1, 2007.
Wilks, D.: “The stippling shows statistically significant grid points”:
How research results are routinely overstated and overinterpreted, and what
to do about it, B. Am. Meteorol. Soc., 97, 2263–2273,
https://doi.org/10.1175/BAMS-D-15-00267.1, 2016.
Short summary
Mistral wind is a renowned phenomenon in the Mediterranean, yet its large-scale controlling mechanisms have not been systematically mapped. Here, using a new mistral database for 1981–2016, the upper-tropospheric flow patterns are classified by a self-organizing map algorithm, resulting in 16 distinct patterns related to Rossby wave life cycles. Each pattern has unique surface impact, having implications to understanding mistral predictability, air–sea interaction and their future projections.
Mistral wind is a renowned phenomenon in the Mediterranean, yet its large-scale controlling...