Articles | Volume 1, issue 2
08 Jul 2020
Research article | 08 Jul 2020
Atmospheric blocking in an aquaplanet and the impact of orography
Veeshan Narinesingh et al.
No articles found.
Katherine L. Towey, James F. Booth, Alejandra Rodriguez Enriquez, and Thomas Wahl
Nat. Hazards Earth Syst. Sci., 22, 1287–1300,Short summary
Coastal flooding due to storm surge from tropical cyclones is a significant hazard. The influence of tropical cyclone characteristics, including its proximity, intensity, path angle, and speed, on the magnitude of storm surge is examined along the eastern United States. No individual characteristic was found to be strongly related to how much surge occurred at a site, though there is an increased likelihood of high surge occurring when tropical cyclones are both strong and close to a location.
Zhen Liu, Yi Ming, Chun Zhao, Ngar Cheung Lau, Jianping Guo, Massimo Bollasina, and Steve Hung Lam Yim
Atmos. Chem. Phys., 20, 223–241,Short summary
OH and HO2 radicals are important trace constituents of the atmosphere that are closely coupled via several types of reaction. This paper describes a new laboratory method to simultaneously determine OH kinetics and HO2 yields from chemical processes. The instrument also provides some time resolution on HO2 detection allowing one to separate HO2 produced from the target reaction from HO2 arising from secondary chemistry. Examples of applications are presented.
Yuxuan Wang, Yuanyu Xie, Wenhao Dong, Yi Ming, Jun Wang, and Lu Shen
Atmos. Chem. Phys., 17, 12827–12843,Short summary
Besides the well-known large impact on agriculture and water resources, drought is associated with significant adverse effects on air quality. Drought-induced degradation of air quality is largely due to natural processes, offsetting the effort of anthropogenic emission reduction during the past decades. Such adverse impacts should be included in modeling processes under current and future climate for mitigation policy.
Related subject area
Dynamical processes in midlatitudesCircumglobal Rossby wave patterns during boreal winter highlighted by space–time spectral analysisHow intense daily precipitation depends on temperature and the occurrence of specific weather systems – an investigation with ERA5 reanalyses in the extratropical Northern HemisphereDifferentiating lightning in winter and summer with characteristics of the wind field and mass fieldFuture changes in the extratropical storm tracks and cyclone intensity, wind speed, and structureAtmospheric blocking and weather extremes over the Euro-Atlantic sector – a reviewIs 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 AlpsHow well is Rossby wave activity represented in the PRIMAVERA coupled simulations?Mediterranean cyclones: current knowledge and open questions on dynamics, prediction, climatology and impactsAutomated detection and classification of synoptic-scale fronts from atmospheric data gridsMulti-day hail clusters and isolated hail days in Switzerland – large-scale flow conditions and precursorsCharacteristics of extratropical cyclones and precursors to windstorms in northern EuropeSystematic assessment of the diabatic processes that modify low-level potential vorticity in extratropical cyclonesThe impact of deep convection representation in a global atmospheric model on the warm conveyor belt and jet stream during NAWDEX IOP6A global analysis of the dry-dynamic forcing during cyclone growth and propagationHow well does CMIP6 capture the dynamics of Euro-Atlantic weather regimes, and why?Smoother versus sharper Gulf Stream and Kuroshio sea surface temperature fronts: effects on cyclones and climatologyOccurrence and transition probabilities of omega and high-over-low blocking in the Euro-Atlantic regionOceanic moisture sources contributing to wintertime Euro-Atlantic blockingReconstructing winter climate anomalies in the Euro-Atlantic sector using circulation patternsLinking air stagnation in Europe with the synoptic- to large-scale atmospheric circulationRelative importance of tropopause structure and diabatic heating for baroclinic instabilityOn the occurrence of strong vertical wind shear in the tropopause region: a 10-year ERA5 northern hemispheric studyLarge-scale drivers of the mistral wind: link to Rossby wave life cycles and seasonal variabilityAn unsupervised learning approach to identifying blocking events: the case of European summerPotential-vorticity dynamics of troughs and ridges within Rossby wave packets during a 40-year reanalysis periodThe 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 variabilityA process-based anatomy of Mediterranean cyclones: from baroclinic lows to tropical-like systemsRepresentation by two climate models of the dynamical and diabatic processes involved in the development of an explosively deepening cyclone during NAWDEXA regime view of future atmospheric circulation changes in northern mid-latitudesA global climatological perspective on the importance of Rossby wave breaking and intense moisture transport for extreme precipitation eventsObservations and simulation of intense convection embedded in a warm conveyor belt – how ambient vertical wind shear determines the dynamical impactThe storm-track suppression over the western North Pacific from a cyclone life-cycle perspectiveMid-level convection in a warm conveyor belt accelerates the jet streamThe role of heat-flux–temperature covariance in the evolution of weather systemsOrganization of convective ascents in a warm conveyor beltVertical cloud structure of warm conveyor belts – a comparison and evaluation of ERA5 reanalysis, CloudSat and CALIPSO dataTropopause-level planetary wave source and its role in two-way troposphere–stratosphere couplingThe life cycle of upper-level troughs and ridges: a novel detection method, climatologies and Lagrangian characteristicsThe sensitivity of atmospheric blocking to upstream latent heating – numerical experimentsThe role of large-scale dynamics in an exceptional sequence of severe thunderstorms in Europe May–June 2018Northern Hemisphere blocking simulation in current climate models: evaluating progress from the Climate Model Intercomparison Project Phase 5 to 6 and sensitivity to resolutionA Lagrangian analysis of upper-tropospheric anticyclones associated with heat waves in EuropeFront–orography interactions during landfall of the 1992 New Year's Day StormPotential vorticity structure of embedded convection in a warm conveyor belt and its relevance for large-scale dynamicsWaveguidability of idealized midlatitude jets and the limitations of ray tracing theoryIdealised simulations of cyclones with robust symmetrically unstable sting jetsThe characteristics and structure of extra-tropical cyclones in a warmer climate
Jacopo Riboldi, Efi Rousi, Fabio D'Andrea, Gwendal Rivière, and François Lott
Weather Clim. Dynam., 3, 449–469,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,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,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,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,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,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,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,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,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,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,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,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,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,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,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.
Joshua Dorrington, Kristian Strommen, and Federico Fabiano
Weather Clim. Dynam. Discuss.,
Revised manuscript accepted for WCDShort 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.
Leonidas Tsopouridis, Thomas Spengler, and Clemens Spensberger
Weather Clim. Dynam., 2, 953–970,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,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,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,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,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,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,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.
Yonatan Givon, Douglas Keller Jr., Vered Silverman, Romain Pennel, Philippe Drobinski, and Shira Raveh-Rubin
Weather Clim. Dynam., 2, 609–630,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.
Carl Thomas, Apostolos Voulgarakis, Gerald Lim, Joanna Haigh, and Peer Nowack
Weather Clim. Dynam., 2, 581–608,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,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,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,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,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.
David L. A. Flack, Gwendal Rivière, Ionela Musat, Romain Roehrig, Sandrine Bony, Julien Delanoë, Quitterie Cazenave, and Jacques Pelon
Weather Clim. Dynam., 2, 233–253,Short summary
The representation of an extratropical cyclone in simulations of two climate models is studied by comparing them to observations of the international field campaign NAWDEX. We show that the current resolution used to run climate model projections (more than 100 km) is not enough to represent the life cycle accurately, but the use of 50 km resolution is good enough. Despite these encouraging results, cloud properties (partitioning liquid and solid) are found to be far from the observations.
Federico Fabiano, Virna L. Meccia, Paolo Davini, Paolo Ghinassi, and Susanna Corti
Weather Clim. Dynam., 2, 163–180,Short summary
Global warming not only affects the mean state of the climate (i.e. a warmer world) but also its variability. Here we analyze a set of future climate scenarios and show how some configurations of the wintertime atmospheric flow will become more frequent and persistent under continued greenhouse forcing. For example, over Europe, models predict an increase in the NAO+ regime which drives intense precipitation in northern Europe and the British Isles and dry conditions over the Mediterranean.
Andries Jan de Vries
Weather Clim. Dynam., 2, 129–161,Short summary
Heavy rainfall can cause dramatic societal impacts. This paper presents the first global study on the role of Rossby wave breaking and intense moisture transport for extreme precipitation events. Several catastrophic flood events demonstrate the importance of these two processes, complemented by a detailed climatological analysis. These findings present a new perspective on the meteorology of extreme precipitation events with implications for their prediction and studies on their future changes.
Annika Oertel, Michael Sprenger, Hanna Joos, Maxi Boettcher, Heike Konow, Martin Hagen, and Heini Wernli
Weather Clim. Dynam., 2, 89–110,Short summary
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.
Sebastian Schemm, Heini Wernli, and Hanin Binder
Weather Clim. Dynam., 2, 55–69,Short summary
North Pacific cyclone intensities are reduced in winter, which is in contrast to North Atlantic cyclones and unexpected from the high available growth potential in winter. We investigate this intensity suppression from a cyclone life-cycle perspective and show that in winter Kuroshio cyclones propagate away from the region where they can grow more quickly, East China Sea cyclones are not relevant before spring, and Kamchatka cyclones grow in a region of reduced growth potential.
Nicolas Blanchard, Florian Pantillon, Jean-Pierre Chaboureau, and Julien Delanoë
Weather Clim. Dynam., 2, 37–53,Short summary
Rare aircraft observations in the warm conveyor belt outflow associated with an extratropical cyclone are complemented with convection-permitting simulations. They reveal a complex tropopause structure with two jet stream cores, from which one is reinforced by bands of negative potential vorticity. They show that negative potential vorticity takes its origin in mid-level convection, which indirectly accelerates the jet stream and, thus, may influence the downstream large-scale circulation.
Andrea Marcheggiani and Maarten H. P. Ambaum
Weather Clim. Dynam., 1, 701–713,Short summary
In this paper, we investigate air–sea interaction by looking at the relationship between spatial variability in surface heat flux and air temperature. We observe that their interaction characterises different stages of storm evolution, thus providing a new perspective on the role played by air–sea heat exchange.
Nicolas Blanchard, Florian Pantillon, Jean-Pierre Chaboureau, and Julien Delanoë
Weather Clim. Dynam., 1, 617–634,Short summary
The study presents the first results from the airborne RASTA observations measured during the North Atlantic Waveguide and Downstream Impact Experiment (NAWDEX). Our combined Eulerian–Lagrangian analysis found three types of organized convection (frontal, banded and mid-level) in the warm conveyor belt (WCB) of the Stalactite cyclone. The results emphasize that convection embedded in WCBs occurs in a coherent and organized manner rather than as isolated cells.
Hanin Binder, Maxi Boettcher, Hanna Joos, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 1, 577–595,Short summary
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.
Lina Boljka and Thomas Birner
Weather Clim. Dynam., 1, 555–575,Short summary
This study addresses the origin and impacts of a source of large-scale atmospheric waves in the lower stratosphere, which have not been examined before. This wave source is caused by interactions of waves of smaller scales. Here we show that as it lies in the lower stratosphere, this wave source can precede extreme events in the stratosphere and that such events can then lead to a response of the tropospheric weather patterns several weeks later (potential for long-term forecasting).
Sebastian Schemm, Stefan Rüdisühli, and Michael Sprenger
Weather Clim. Dynam., 1, 459–479,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.
Daniel Steinfeld, Maxi Boettcher, Richard Forbes, and Stephan Pfahl
Weather Clim. Dynam., 1, 405–426,Short summary
The effect of latent heating on atmospheric blocking is investigated using numerical sensitivity experiments. The modification of latent heating in the upstream cyclone has substantial effects on the upper-tropospheric circulation, demonstrating that some blocking systems do not develop at all without upstream latent heating. The results highlight the importance of moist-diabatic processes for the dynamics of prolonged anticyclonic circulation anomalies.
Susanna Mohr, Jannik Wilhelm, Jan Wandel, Michael Kunz, Raphael Portmann, Heinz Jürgen Punge, Manuel Schmidberger, Julian F. Quinting, and Christian M. Grams
Weather Clim. Dynam., 1, 325–348,Short summary
We investigated an exceptional thunderstorm episode in 2018, in which atmospheric blocking provided large-scale environmental conditions favouring convection. Furthermore, blocking was accompanied by a high cut-off frequency on its upstream side, which together with filaments of high PV provided the mesoscale setting for deep moist convection. The exceptional persistence of low stability combined with weak wind speed in the mid-troposphere over more than 3 weeks has never been observed before.
Reinhard Schiemann, Panos Athanasiadis, David Barriopedro, Francisco Doblas-Reyes, Katja Lohmann, Malcolm J. Roberts, Dmitry V. Sein, Christopher D. Roberts, Laurent Terray, and Pier Luigi Vidale
Weather Clim. Dynam., 1, 277–292,Short summary
In blocking situations the westerly atmospheric flow in the midlatitudes is blocked by near-stationary high-pressure systems. Blocking can be associated with extremes such as cold spells and heat waves. Climate models are known to underestimate blocking occurrence. Here, we assess the latest generation of models and find improvements in simulated blocking, partly due to increases in model resolution. These new models are therefore more suitable for studying climate extremes related to blocking.
Philipp Zschenderlein, Stephan Pfahl, Heini Wernli, and Andreas H. Fink
Weather Clim. Dynam., 1, 191–206,Short summary
We analyse the formation of upper-tropospheric anticyclones connected to European surface heat waves. Tracing air masses backwards from these anticyclones, we found that trajectories are diabatically heated in two branches, either by North Atlantic cyclones or by convection closer to the heat wave anticyclone. The first branch primarily affects the onset of the anticyclone, while the second branch is more relevant for the maintenance. Our results are relevant for heat wave predictions.
Clemens Spensberger and Sebastian Schemm
Weather Clim. Dynam., 1, 175–189,Short summary
In this paper, we take a second look at the development of an intense storm that made landfall in Norway a few hours into the new year of 1992, focussing on the effect of the Scandinavian mountains on the storm. We find that the cyclone core evolves largely unaffected, although both the warm and the cold fronts decay rapidly while passing over the mountains. This result suggests that the fronts of a cyclone can become detached from their cyclone core as part of the cyclone’s occlusion process.
Annika Oertel, Maxi Boettcher, Hanna Joos, Michael Sprenger, and Heini Wernli
Weather Clim. Dynam., 1, 127–153,Short summary
Warm conveyor belts (WCBs) are important, mainly stratiform cloud forming airstreams in extratropical cyclones that can include embedded convection. This WCB case study systematically compares the characteristics of convective vs. slantwise ascent of the WCB. We find that embedded convection leads to regions of significantly stronger precipitation. Moreover, it strongly modifies the potential vorticity distribution in the lower and upper troposphere, where its also influences the waveguide.
Weather Clim. Dynam., 1, 111–125,Short summary
This paper investigates the waveguidability of midlatitude jets, i.e., their ability to duct Rossby waves in the zonal direction. Waveguidability is quantified in the framework of an idealized numerical model and compared with the predictions from two complementary theoretical concepts. It is found that the concept of ray tracing, which has been used extensively in the past, does not provide a satisfactory explanation for the numerical results. Further analysis uncovers the underlying reasons.
Ambrogio Volonté, Peter A. Clark, and Suzanne L. Gray
Weather Clim. Dynam., 1, 63–91,Short summary
Sting jets (SJs) can lead to strong surface winds by descending into the frontal-fracture region of intense extratropical cyclones. In this study we look at idealised simulations of SJ-containing cyclones produced using an improved initial state and a wide set of sensitivity experiments. The results clarify the role of dry instabilities in SJ dynamics and evolution, supporting a recent conceptual model. The simulations also highlight the robustness of SJ occurrence in these intense cyclones.
Victoria A. Sinclair, Mika Rantanen, Päivi Haapanala, Jouni Räisänen, and Heikki Järvinen
Weather Clim. Dynam., 1, 1–25,Short summary
We studied how mid-latitude cyclones are likely to change in the future. We used a state-of-the-art numerical model and performed a control and a
warmexperiment. The total number of cyclones did not change with warming and neither did the average strength, but there were more stronger and more weaker storms in the warm experiment. Precipitation associated with the most extreme mid-latitude cyclones increased by up to 50 % and occurred in a more poleward location in the warmer experiment.
Abatzoglou, J. T. and Magnusdottir, G.: Planetary Wave Breaking and Nonlinear Reflection, J. Climate, 19, 6139–6152, https://doi.org/10.1175/JCLI3968.1, 2006.
Barnes, E., Slingo, J., and Woollings, T.: A methodology for the comparison of blocking climatologies across indices, models and climate scenarios, Clim. Dynam., 38, 2467–2481, https://doi.org/10.1007/s00382-011-1243-6, 2012.
Barriopedro, D., García-Herrera, R., and Trigo, R.: Application of blocking diagnosis methods to General Circulation Models. Part I: a novel detection scheme, Clim. Dynam., 35, 1373–1391, https://doi.org/10.1007/s00382-010-0767-5, 2010.
Berggren, R., Bolin, B., and Rossby, C.-G.: An Aerological Study of Zonal Motion, its Perturbations and Break-down, Tellus, 1, 14–37, https://doi.org/10.3402/tellusa.v1i2.8501, 1949.
Berrisford, P., Hoskins, B. J., and Tyrlis, E.: Blocking and Rossby Wave Breaking on the Dynamical Tropopause in the Southern Hemisphere, J. Atmos. Sci., 64, 2881–2898, https://doi.org/10.1175/JAS3984.1, 2007.
Booth, J. F., Dunn-Sigouin, E., and Pfahl, S.: The Relationship Between Extratropical Cyclone Steering and Blocking Along the North American East Coast, Geophys Res. Lett., 44, 11976–11984, https://doi.org/10.1002/2017GL075941, 2017a.
Booth, J. F., Kwon, Y.-K., Ko, S., Small, J., and Madsek, R.: Spatial Patterns and Intensity of the Surface Storm Tracks in CMIP5 Models J. Climate, 30, 4965–4981, 2017b.
Bowley, K. A., Gyakum, J. R., and Atallah, E. H.: A New Perspective toward Cataloging Northern Hemisphere Rossby Wave Breaking on the Dynamic Tropopause, Mon. Weather Rev., 147, 409–431, https://doi.org/10.1175/MWR-D-18-0131.1, 2019.
Brayshaw, D. J., Hoskins, B., and Blackburn, M.: The Basic Ingredients of the North Atlantic Storm Track. Part I: Land–Sea Contrast and Orography, J. Atmos. Sci., 66, 2539–2558, https://doi.org/10.1175/2009JAS3078.1, 2009.
Brunner, L. and Steiner, A.: A global perspective on atmospheric blocking using GPS radio occultation – one decade of observations, Atmos. Meas. Tech., 10, 4727–4745, https://doi.org/10.5194/amt-10-4727-2017, 2017.
Brunner, L., Schaller, N., Anstey, J., Sillmann, J., and Steiner, A.: Dependence of Present and Future European Temperature Extremes on the Location of Atmospheric Blocking, Geophys. Res. Lett., 45, 6311–6320, https://doi.org/10.1029/2018GL077837, 2018.
Cassou, C., Terray, L., and Phillips, A. S.: Tropical Atlantic Influence on European Heat Waves, J. Climate, 18, 2805–2811, https://doi.org/10.1175/JCLI3506.1, 2005.
Chang, E. K. M., Lee, S., and Swanson, K. L.: Storm Track Dynamics, J. Climate, 15, 2163–2183, https://doi.org/10.1175/1520-0442(2002)015<02163:STD>2.0.CO;2, 2002.
Charney, J. G. and DeVore, J. G.: Multiple Flow Equilibria in the Atmosphere and Blocking, J. Atmos. Sci., 36, 1205–1216, https://doi.org/10.1175/1520-0469(1979)036<1205:MFEITA>2.0.CO;2, 1979.
Clark, S. K., Ming, Y., Held, I. M., and Phillips, P. J.: The Role of the Water Vapor Feedback in the ITCZ Response to Hemispherically Asymmetric Forcings, J. Climate, 31, 3659–3678, https://doi.org/10.1175/JCLI-D-17-0723.1, 2018.
Clark, S. K., Ming, Y., and Adames, Á. F.: Monsoon low pressure system like variability in an idealized moist model, J. Climate, 33, 2051–2074, https://doi.org/10.1175/JCLI-D-19-0289.1, 2019.
Colucci, S. J.: Explosive Cyclogenesis and Large-Scale Circulation Changes: Implications for Atmospheric Blocking, J. Atmos. Sci., 42, 2701–2717, https://doi.org/10.1175/1520-0469(1985)042<2701:ECALSC>2.0.CO;2, 1985.
Cook, K. and Held, I. M.: The Stationary Response to Large-Scale Orography in a General Circulation Model and a Linear Model, J. Atmos. Sci., 49, 525–539, https://doi.org/10.1175/1520-0469(1992)049<0525:TSRTLS>2.0.CO;2, 1992.
Croci-Maspoli, M., Schwierz, C., and Davies, H. C.: A Multifaceted Climatology of Atmospheric Blocking and Its Recent Linear Trend, J. Climate, 20, 633–649, https://doi.org/10.1175/JCLI4029.1, 2007.
D'Andrea, F., Tibaldi, S., Blackburn, M., Boer, G., Déqué, M., Dix, M. R., Dugas, B., Ferranti, L., Iwasaki, T., Kitoh, A., Pope, V., Randall, D., Roeckner, E., Strauss, D., Stern, H., Van den Dool, W., and Williamson, D.: Northern Hemisphere atmospheric blocking as simulated by 15 atmospheric general circulation models in the period 1979–1988, Clim. Dynam., 14, 385–407, https://doi.org/10.1007/s003820050230, 1998.
Danielson, R. E., Gyakum, J. R., and Straub, D. N.: A Case Study of Downstream Baroclinic Development over the North Pacific Ocean. Part II: Diagnoses of Eddy Energy and Wave Activity, Mon. Weather Rev., 134, 1549–1567, https://doi.org/10.1175/MWR3173.1, 2006.
Davini, P., Cagnazzo, C., Gualdi, S., and Navarra, A.: Bidimensional Diagnostics, Variability, and Trends of Northern Hemisphere Blocking, J. Climate, 25, 6496–6509, https://doi.org/10.1175/JCLI-D-12-00032.1, 2012.
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., Hólm, E. V., Isaksen, L., Kållberg, P., Köhler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J., Park, B., Peubey, C., de Rosnay, P., Tavolato, C., Thépaut, J., and Vitart, F.: The ERA-Interim reanalysis: configuration and performance of the data assimilation system, Q. J. Roy. Meteorol. Soc., 137, 553–597, https://doi.org/10.1002/qj.828, 2011 (data available at: https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era-interim/, last access: 1 July 2020).
Dole, R., Hoerling, M., Perlwitz, J., Eischeid, J., Pegion, P., Zhang, T., Quan, X., Xu, T., and Murray, D.: Was there a basis for anticipating the 2010 Russian heat wave?, Geophys. Res. Lett., 38, L06702, https://doi.org/10.1029/2010GL046582, 2011.
Dong, L., Mitra, C., Greer, S., and Burt, E.: The Dynamical Linkage of Atmospheric Blocking to Drought, Heatwave and Urban Heat Island in Southeastern US: A Multi-Scale Case Study, Atmosphere, 9, 33, https://doi.org/10.3390/atmos9010033, 2018.
Dunn-Sigouin, E. and Son, S.: Northern Hemisphere blocking frequency and duration in the CMIP5 models, J. Geophys. Res.-Atmos., 118, 1179–1188, https://doi.org/10.1002/jgrd.50143, 2013.
Egger, J.: Dynamics of Blocking Highs, J. Atmos. Sci., 35, 1788–1801, https://doi.org/10.1175/1520-0469(1978)035<1788:DOBH>2.0.CO;2, 1978.
Frierson, D. M. W.: The Dynamics of Idealized Convection Schemes and Their Effect on the Zonally Averaged Tropical Circulation, J. Atmos. Sci., 64, 1959–1976, https://doi.org/10.1175/JAS3935.1, 2007.
Frierson, D. M. W., Held, I. M., and Zurita-Gotor, P.: A Gray-Radiation Aquaplanet Moist GCM. Part I: Static Stability and Eddy Scale, J. Atmos. Sci., 63, 2548–2566, https://doi.org/10.1175/JAS3753.1, 2006.
Frierson, D. M. W., Held, I. M., and Zurita-Gotor, P.: A Gray-Radiation Aquaplanet Moist GCM. Part II: Energy Transports in Altered Climates, J. Atmos. Sci., 64, 1680–1693, https://doi.org/10.1175/JAS3913.1, 2007.
Geen, R., Lambert, F. H., and Vallis, G. K.: Regime Change Behavior during Asian Monsoon Onset, J. Climate, 31, 3327–3348, https://doi.org/10.1175/JCLI-D-17-0118.1, 2018.
Grose, W. L. and Hoskins, B. J.: On the Influence of Orography on Large-Scale Atmospheric Flow, J. Atmos. Sci., 36, 223–234, https://doi.org/10.1175/1520-0469(1979)036<0223:OTIOOO>2.0.CO;2, 1979.
Guo, Y., Chang, E. K. M., and Leroy, S. S.: How strong are the Southern Hemisphere storm tracks?, Geophys. Res. Lett., 36, L22806, https://doi.org/10.1029/2009GL040733, 2009.
Hassanzadeh, P., Kuang, Z., and Farrell, B. F.: Responses of midlatitude blocks and wave amplitude to changes in the meridional temperature gradient in an idealized dry GCM, Geophys. Res. Lett., 41, 5223–5232, https://doi.org/10.1002/2014GL060764, 2014.
Held, I. M., Ting, M., and Wang, H.: Northern Winter Stationary Waves, J. Climate, 15, 2125–2144, https://doi.org/10.1175/1520-0442(2002)015<2125:NWSWTA>2.0.CO;2, 2002.
Hodges, K. I., Lee, R. W., and Bengtsson, L.: A Comparison of Extratropical Cyclones in Recent Reanalyses ERA-Interim, NASA MERRA, NCEP CFSR, and JRA-25, J. Climate, 24, 4888–4906, https://doi.org/10.1175/2011JCLI4097.1, 2011.
Hu, Y., Yang, D., and Yang, J.: Blocking systems over an aqua planet, Geophys. Res. Lett., 35, L19818, https://doi.org/10.1029/2008GL035351, 2008.
Luo, D.: A Barotropic Envelope Rossby Soliton Model for Block–Eddy Interaction. Part I: Effect of Topography, J. Atmos. Sci., 62, 5–21, https://doi.org/10.1175/1186.1, 2005.
Lutsko, N. J. and Held, I. M.: The Response of an Idealized Atmosphere to Orographic Forcing: Zonal versus Meridional Propagation, J. Atmos. Sci., 73, 3701–3718, https://doi.org/10.1175/JAS-D-16-0021.1, 2016.
Manabe, S. and Terpstra, T. B.: The Effects of Mountains on the General Circulation of the Atmosphere as Identified by Numerical Experiments, J. Atmos. Sci., 31, 3–42, https://doi.org/10.1175/1520-0469(1974)031<0003:TEOMOT>2.0.CO;2, 1974.
Masato, G., Hoskins, B. J., and Woollings, T. J.: Wave-breaking characteristics of midlatitude blocking, Q. J. Roy. Meteorol. Soc., 138, 1285–1296, https://doi.org/10.1002/qj.990, 2012.
Matsueda, M., Mizuta, R., and Kusunoki, S.: Future change in wintertime atmospheric blocking simulated using a 20-km-mesh atmospheric global circulation model, J. Geophys. Res.-Atmos., 114, D12114, https://doi.org/10.1029/2009JD011919, 2009.
Mattingly, K. S., McLeod, J. T., Knox, J. A., Shepherd, J. M., and Mote, T. L.: A climatological assessment of Greenland blocking conditions associated with the track of Hurricane Sandy and historical North Atlantic hurricanes, Int. J. Climatol., 35, 746–760, https://doi.org/10.1002/joc.4018, 2015.
Nabizadeh, E., Hassanzadeh, P., Yang, D., and Barnes, E. A.: Size of the Atmospheric Blocking Events: Scaling Law and Response to Climate Change, Geophys. Res. Lett., 46, 13488–13499, https://doi.org/10.1029/2019GL084863, 2019.
Nakamura, H., Nakamura, M., and Anderson, J. L.: The Role of High- and Low-Frequency Dynamics in Blocking Formation, Mon. Weather Rev., 125, 2074–2093, https://doi.org/10.1175/1520-0493(1997)125<2074:TROHAL>2.0.CO;2, 1997.
Nakamura, H. and Shimpo, A.: Seasonal Variations in the Southern Hemisphere Storm Tracks and Jet Streams as Revealed in a Reanalysis Dataset, J. Climate, 17, 1828–1844, https://doi.org/10.1175/1520-0442(2004)017<1828:SVITSH>2.0.CO;2, 2004.
Nakamura, N. and Huang, C. S. Y.: Atmospheric blocking as a traffic jam in the jet stream, Science, 361, 42–47, https://doi.org/10.1126/science.aat0721, 2018.
O'Gorman, P. A. and Schneider, T.: The Hydrological Cycle over a Wide Range of Climates Simulated with an Idealized GCM, J. Climate, 21, 3815–3832, https://doi.org/10.1175/2007JCLI2065.1, 2008.
Parsons, S., Renwick, J. A., and McDonald, A. J.: An Assessment of Future Southern Hemisphere Blocking Using CMIP5 Projections from Four GCMs, J. Climate, 29, 7599–7611, https://doi.org/10.1175/JCLI-D-15-0754.1, 2016.
Pelly, J. L. and Hoskins, B. J.: A New Perspective on Blocking, J. Atmos. Sci., 60, 743–755, https://doi.org/10.1175/1520-0469(2003)060<0743:ANPOB>2.0.CO;2, 2003.
Pfahl, S. and Wernli, H.: Quantifying the relevance of atmospheric blocking for co-located temperature extremes in the Northern Hemisphere on (sub-)daily time scales, Geophys. Res. Lett., 39, L12807, https://doi.org/10.1029/2012GL052261, 2012.
Pithan, F., Shepherd, T. G., Zappa, G., and Sandu, I.: Climate model biases in jet streams, blocking and storm tracks resulting from missing orographic drag, Geophys. Res. Lett., 43, 7231–7240, https://doi.org/10.1002/2016GL069551, 2016.
Quintanar, A. I. and Mechoso, C. R.: Quasi-Stationary Waves in the Southern Hemisphere. Part I: Observational Data, J. Climate, 8, 2659–2672, https://doi.org/10.1175/1520-0442(1995)008<2659:QSWITS>2.0.CO;2, 1995.
Renwick, J. A.: Persistent Positive Anomalies in the Southern Hemisphere Circulation, Mon. Weather Rev., 133, 977–988, https://doi.org/10.1175/MWR2900.1, 2005.
Rex, D. F.: Blocking Action in the Middle Troposphere and its Effect upon Regional Climate, Tellus, 2, 196–211, https://doi.org/10.3402/tellusa.v2i3.8546, 1950.
Sausen, R., König, W., and Sielmann, F.: Analysis of blocking events from observations and ECHAM model simulations, Tellus A, 47, 421–438, https://doi.org/10.3402/tellusa.v47i4.11526, 1995.
Shutts, G. J.: The propagation of eddies in diffluent jetstreams: Eddy vorticity forcing of `blocking' flow fields, Q. J. Roy. Meteorol. Soc., 109, 737–761, https://doi.org/10.1002/qj.49710946204, 1983.
Sillmann, J., Croci-Maspoli, M., Kallache, M., and Katz, R. W.: Extreme Cold Winter Temperatures in Europe under the Influence of North Atlantic Atmospheric Blocking, J. Climate, 24, 5899–5913, https://doi.org/10.1175/2011JCLI4075.1, 2011.
Takaya, K. and Nakamura, H.: A Formulation of a Phase-Independent Wave-Activity Flux for Stationary and Migratory Quasigeostrophic Eddies on a Zonally Varying Basic Flow, J. Atmos. Sci., 58, 608–627, https://doi.org/10.1175/1520-0469(2001)058<0608:AFOAPI>2.0.CO;2, 2001.
Tibaldi, S., Tosi, E., Navarra, A., and Pedulli, L.: Northern and Southern Hemisphere Seasonal Variability of Blocking Frequency and Predictability. Mon. Weather Rev., 122, 1971–2003, https://doi.org/10.1175/1520-0493(1994)122<1971:NASHSV>2.0.CO;2, 1994.
Troen, I. B. and Mahrt, L.: A simple model of the atmospheric boundary layer; sensitivity to surface evaporation, Bound.-Lay. Meteorol., 37, 129–148, https://doi.org/10.1007/BF00122760, 1986.
Tung, K. K. and Lindzen, R. S.: A Theory of Stationary Long Waves. Part I: A Simple Theory of Blocking, Mon. Weather Rev., 107, 714–734, https://doi.org/10.1175/1520-0493(1979)107<0714:ATOSLW>2.0.CO;2, 1979.
Valdes, P. J. and Hoskins, B. J.: Nonlinear Orographically Forced Planetary Waves, J. Atmos. Sci., 48, 2089–2106, https://doi.org/10.1175/1520-0469(1991)048<2089:NOFPW>2.0.CO;2, 1991.
Vallis, G. K., Colyer, G., Geen, R., Gerber, E., Jucker, M., Maher, P., Paterson, A., Pietschnig, M., Penn, J., and Thomson, S. I.: Isca, v1.0: a framework for the global modelling of the atmospheres of Earth and other planets at varying levels of complexity, Geosci. Model Dev., 11, 843–859, https://doi.org/10.5194/gmd-11-843-2018, 2018.
Wallace, J. M., Lim, G., and Blackmon, M. L.: Relationship between Cyclone Tracks, Anticyclone Tracks and Baroclinic Waveguides, J. Atmos. Sci., 45, 439–462, https://doi.org/10.1175/1520-0469(1988)045<0439:RBCTAT>2.0.CO;2, 1988.
Wang, L. and Kuang, Z.: Evidence against a general positive eddy feedback in atmospheric blocking, arXiv preprint: arXiv:1907.00999, 2019.
White, R. H., Battisti, D. S., and Roe, G. H.: Mongolian Mountains Matter Most: Impacts of the Latitude and Height of Asian Orography on Pacific Wintertime Atmospheric Circulation, J. Climate, 30, 4065–4082, https://doi.org/10.1175/JCLI-D-16-0401.1, 2017.
Wiedenmann, J. M., Lupo, A. R., Mokhov, I. I., and Tikhonova, E. A.: The Climatology of Blocking Anticyclones for the Northern and Southern Hemispheres: Block Intensity as a Diagnostic, J. Climate, 15, 3459–3473, https://doi.org/10.1175/1520-0442(2002)015<3459:TCOBAF>2.0.CO;2, 2002.
Wirth, V., Riemer, M., Chang, E. K. M., and Martius, O.: Rossby Wave Packets on the Midlatitude Waveguide – A Review, Mon. Weather Rev., 146, 1965–2001, https://doi.org/10.1175/MWR-D-16-0483.1, 2018.
Woollings, T., Barriopedro, D., Methven, J., Son, S., Martius, O., Harvey, B., Sillmann, J., Lupo, A., and Seneviratne, S.: Blocking and its Response to Climate Change, Curr. Clim. Change Rep., 4, 287–300, https://doi.org/10.1007/s40641-018-0108-z, 2018.
Yamazaki, A. and Itoh, H.: Vortex–Vortex Interactions for the Maintenance of Blocking. Part I: The Selective Absorption Mechanism and a Case Study, J. Atmos. Sci., 70, 725–742, https://doi.org/10.1175/JAS-D-11-0295.1, 2013.
This work investigates the influence of orography on atmospheric blocking dynamics, spatial frequency, and duration. Using an idealized model, a landless integration and integrations with mountains are analyzed. The dynamical evolution of blocking in the idealized model is found to be similar to reanalysis. Orography is found to significantly increase blocking and anchors where blocks most likely occur (i.e., just upstream from mountains and near storm track exits).
This work investigates the influence of orography on atmospheric blocking dynamics, spatial...