• Characteristics of cyclones following different pathways in the Gulf Stream region 

      Tsopouridis, Leonidas; Spensberger, Clemens; Spengler, Thomas (Journal article; Peer reviewed, 2021)
      The Northwest Atlantic is a region of strong temperature gradients and hence is a favourable location for wintertime cyclone intensification co-located with the storm track. The temperature gradient is associated with both ...
    • Complementing Scientific Monsoon Definitions with Social Perception in Bangladesh 

      Reeve, Mathew Alexander; Syed, Mohammed Abu; Spengler, Thomas; Spinney, Jennifer A.; Hossain, Rumana (Peer reviewed; Journal article, 2015-01)
      The monsoon onset is a critical event in the Bangladesh calendar, especially for the domestic agricultural sector. Providing information about the monsoon onset for the past, present, and future has potential benefit for ...
    • The connection between the Southern Annular Mode and a feature-based perspective on Southern Hemisphere mid-latitude winter variability 

      Spensberger, Clemens; Reeder, Michael John; Spengler, Thomas; Patterson, Matthew (Journal article; Peer reviewed, 2020)
      This article provides a reconciling perspective on the two main, but contradictory, interpretations of the southern annular mode (SAM). SAM was originally thought to characterize meridional shifts in the storm track across ...
    • Cyclone Intensification in the Kuroshio Region and its relation to the Sea Surface Temperature Front and Upper‐Level Forcing 

      Tsopouridis, Leonidas; Spensberger, Clemens; Spengler, Thomas (Journal article; Peer reviewed, 2021)
      The Northwest Pacific features strong sea surface temperature (SST) gradients providing favourable conditions for wintertime cyclone intensification in the midlatitudes. To estimate the relative contribution of the SST ...
    • Diabatic Heating as a Pathway for Cyclone Clustering Encompassing the Extreme Storm Dagmar 

      Weijenborg, Christian; Spengler, Thomas (Journal article, 2020)
      Contrary to the general notion that extratropical cyclones reduce baroclinicity, the baroclinicity is found to be enhanced in the wake of the extreme winter storm Dagmar. Thus, individual storms can increase baroclinicity, ...
    • Direct and Indirect Effects of Surface Fluxes on Moist Baroclinic Development in an Idealized Framework 

      Haualand, Kristine Flacké; Spengler, Thomas (Journal article; Peer reviewed, 2020-09)
      The convoluted role of surface sensible and latent heat fluxes on moist baroclinic development demands a better understanding to disentangle their local and remote effects. Including diabatic effects in the Eady model, the ...
    • The Effect of Sea Surface Temperature Fronts on Atmospheric Frontogenesis 

      Reeder, Michael J; Spengler, Thomas; Spensberger, Clemens (Journal article; Peer reviewed, 2021)
      It is thought that the sensible heat fluxes associated with sea surface temperature (SST) fronts can affect the genesis and evolution of atmospheric fronts. An analytic model is developed and used to explore this idea. The ...
    • Factors affecting extreme rainfall events in the South Pacific 

      Pariyar, Sunil Kumar; Keenlyside, Noel; Sorteberg, Asgeir; Spengler, Thomas; Bhatt, Bhuwan Chandra; Ogawa, Fumiaki (Journal article; Peer reviewed, 2020)
      Extreme rainfall events in the South Pacific are widespread and affected by various factors on different time scales. We use daily rainfall data from 20 stations over the South Pacific to investigate the characteristics ...
    • Feature-Based Jet Variability in the Upper Troposphere 

      Spensberger, Clemens; Spengler, Thomas (Journal article; Peer reviewed, 2020)
      Jets in the upper troposphere constitute a cornerstone of both synoptic meteorology and climate dynamics, providing a direct link between weather and midlatitude climate variability. Conventionally, jet variability is often ...
    • FLOHOF 2007: an overview of the mesoscale meteorological field campaign at Hofsjökull, Central Iceland 

      Reuder, Joachim; Ablinger, Markus; Ágústsson, Hálfdán; Brisset, Pascal; Brynjólfsson, Sveinn; Garhammer, Markus; Jóhannesson, Tómas; Jonassen, Marius O.; Kühnel, Rafael; Lämmlein, Stephan; de Lange, Tor; Lindenberg, Christian; Malardel, Sylvie; Mayer, Stephanie; Müller, Martin; Ólafsson, Haraldur; Rögnvaldsson, Ólafur; Schäper, Wolfgang; Spengler, Thomas; Zängl, Günther; Egger, Joseph (Peer reviewed; Journal article, 2012-04)
      The FLOHOF field campaign took place in the period July 21 to August 24, 2007 on and in the surroundings of Hofsjökull glacier in Central Iceland. During the campaign, 18 automatic weather stations (AWS) recording temperature, ...
    • How does latent cooling affect baroclinic development in an idealized framework? 

      Haualand, Kristine Flacké; Spengler, Thomas (Peer reviewed; Journal article, 2019)
      Latent cooling by evaporating or melting hydrometeors has recently been shown to contribute to the positive low-level potential vorticity (PV) anomaly below the layer of latent heating in midlatitude cyclones. While the ...
    • The Iceland Greenland seas project 

      Renfrew, Ian Alasdair; Pickart, RS; Våge, Kjetil; Moore, GWK; Bracegirdle, TJ; Elvidge, AD; Jeansson, Emil; Lachlan-Cope, T; McRaven, LT; Papritz, L; Reuder, Joachim; Sodemann, Harald; Terpstra, Annick; Waterman, S; Valdimarsson, H; Weiss, A; Almansi, M; Bahr, F; Brakstad, Ailin; Barrell, C; Brooke, JK; Brooks, BJ; Brooks, IM; Brooks, ME; Bruvik, Erik Magnus; Duscha, Christiane; Fer, Ilker; Golid, Heidi M.; Hallerstig, Matilda; Hessevik, Idar; Huang, J; Houghton, L; Jonsson, S; Jonassen, Marius Opsanger; Jackson, Kristin; Kvalsund, Karsten; Kolstad, Erik Wilhelm; Konstali, Kjersti; Kristiansen, Jørn; Ladkin, R; Lin, P; MacRander, A; Mitchell, A; Olafsson, H; Pacini, A; Payne, C; Palmason, B; Perez-Hernandez, MD; Peterson, Algot Kristoffer; Petersen, GN; Pisareva, MN; Pope, JO; Seidl, Andrew; Semper, Stefanie; Sergeev, D; Skjelsvik, Silje; Søiland, Henrik; Smith, D; Spall, MA; Spengler, Thomas; Touzeau, Alexandra; Tupper, G; Weng, Yongbiao; Williams, KD; Yang, X; Zhou, Shenjie (Peer reviewed; Journal article, 2019)
      The Iceland Greenland Seas Project (IGP) is a coordinated atmosphere–ocean research program investigating climate processes in the source region of the densest waters of the Atlantic meridional overturning circulation. ...
    • IsoTrotter: Visually Guided Empirical Modelling of Atmospheric Convection 

      Palenik, Juraj; Spengler, Thomas; Hauser, Helwig (Journal article; Peer reviewed, 2020)
      Empirical models, fitted to data from observations, are often used in natural sciences to describe physical behaviour and support discoveries. However, with more complex models, the regression of parameters quickly becomes ...
    • A New Look at Deformation as a Diagnostic for Large-Scale Flow 

      Spensberger, Clemens; Spengler, Thomas (Peer reviewed; Journal article, 2014-11)
      Deformation plays a key role in atmospheric dynamics because it provides a dynamical measure of the interaction between different scales, such as in frontogenesis. A climatology of deformation constructed from Interim ECMWF ...
    • The North Atlantic waveguide and downstream impact experiment 

      Schäfler, Andreas; Craig, George; Wernli, Heini; Arbogast, Philippe; Doyle, James D.; McTaggart-Cowan, Ron; Methven, John; Rivière, Gwendal; Ament, Felix; Boettcher, Maxi; Bramberger, Martina; Cazenave, Quitterie; Cotton, Richard; Crewell, Susannne; Delanoë, Julien; Dörnbrack, Andreas; Ehrlich, André; Ewald, Florian; Fix, Andreas; Grams, Christian M.; Gray, Suzanne L.; Grob, Johannes; Groß, Silke; Hagen, Martin; Harvey, Ben; Hirsch, Lutz; Jacob, Marek; Kölling, Tobias; Konow, Heike; Lemmerz, Christian; Lux, Oliver; Magnusson, Linus; Mayer, Bernhard; Mech, Mario; Moore, Richard; Pelon, Jacques; Quinting, Julian; Rahm, Stephan; Rapp, Markus; Rautenhaus, Marc; Reitebuch, Oliver; Reynolds, Carlolyn A.; Sodemann, Harald; Spengler, Thomas; Vaughan, Geraint; Wendisch, Manfred; Wirth, Martin; Witschas, Benjamin; Wolf, Kevin; Zinner, Tobias (Peer reviewed; Journal article, 2018)
      The North Atlantic Waveguide and Downstream Impact Experiment (NAWDEX) explored the impact of diabatic processes on disturbances of the jet stream and their influence on downstream high-impact weather through the deployment ...
    • On the Influence of Sea Surface Temperature distributions on the Development of Extratropical Cyclones 

      Bui, Hai Hoang; Spengler, Thomas (Journal article; Peer reviewed, 2021)
      The sea surface temperature (SST) distribution can modulate the development of extratropical cyclones through sensible and latent heat fluxes. However, the direct and indirect effects of these surface fluxes, and thus the ...
    • Polar low workshop 

      Heinemann, Günther; Claud, Chantal; Spengler, Thomas (Journal article, 2019)
    • Polar lows – moist-baroclinic cyclones developing in four different vertical wind shear environments 

      Stoll, Patrick; Spengler, Thomas; Terpstra, Annick; Graversen, Rune (Journal article; Peer reviewed, 2021)
      Polar lows are intense mesoscale cyclones that develop in polar marine air masses. Motivated by the large variety of their proposed intensification mechanisms, cloud structure, and ambient sub-synoptic environment, we use ...
    • Prevailing Surface Wind Direction during Air-Sea Heat Exchange 

      Ogawa, Fumiaki; Spengler, Thomas (Peer reviewed; Journal article, 2019)
      While the climatological-mean sensible and latent heat fluxes are remarkably well described using climatological-mean fields in the bulk flux formulas, this study shows that a significant fraction of the climatological-mean ...
    • Relative importance of tropopause structure and diabatic heating for baroclinic instability 

      Haualand, Kristine Flacké; Spengler, Thomas (Journal article; Peer reviewed, 2021)
      Misrepresentations of wind shear and stratification around the tropopause in numerical weather prediction models can lead to errors in potential vorticity gradients with repercussions for Rossby wave propagation and ...