Search Results

You are looking at 1 - 5 of 5 items for :

  • Weather modification x
  • Predictability and Dynamics of Weather Systems in the Atlantic-European Sector (PANDOWAE) x
  • Waves to Weather (W2W) x
  • All content x
Clear All
Julia H. Keller, Christian M. Grams, Michael Riemer, Heather M. Archambault, Lance Bosart, James D. Doyle, Jenni L. Evans, Thomas J. Galarneau Jr., Kyle Griffin, Patrick A. Harr, Naoko Kitabatake, Ron McTaggart-Cowan, Florian Pantillon, Julian F. Quinting, Carolyn A. Reynolds, Elizabeth A. Ritchie, Ryan D. Torn, and Fuqing Zhang

amplification of the ridge–trough couplet directly downstream of ET. More recent work has investigated the processes that determine downstream development following the onset of ET beyond one wavelength [see Fig. 2 and blue labels for orientation; section 3a(1) ] and identified a climatological signal of RWP development downstream of ET [ section 3a(2) ]. Furthermore, the development of high-impact weather in regions downstream of ET has been investigated more recently ( section 3b ). a. Modification of

Open access
Volkmar Wirth, Michael Riemer, Edmund K. M. Chang, and Olivia Martius

addressed the following important questions: Do these local modifications exhibit a downstream impact (i.e., do they modify the propagation of RWPs)? And how important are modifications by latent heat release compared to dry dynamics? Early studies demonstrated a clear impact of latent heat release on individual weather events in the downstream region [e.g., a cyclone as in Hoskins and Berrisford (1988) , or heavy precipitation as in Massacand et al. (2001) ]. More recent studies interpreted the

Open access
Hilke S. Lentink, Christian M. Grams, Michael Riemer, and Sarah C. Jones

1. Introduction The extratropical transition (ET) of tropical cyclones (TCs) is associated with high-impact weather, both locally and in downstream regions ( Jones et al. 2003 ; Evans et al. 2017 ). The local direct impact is mainly caused by strong wind gusts and excessive precipitation. These are not always well forecasted because a numerical weather prediction model is prone to small errors that evolve during the complex interaction between a poleward-moving TC and its environment. The

Full access
Gabriel Wolf and Volkmar Wirth

1. Introduction Midlatitude weather is dominated by a succession of synoptic-scale cyclones and anticyclones. These, in turn, are often accompanied by longer-lived and larger-scale Rossby wave packets (RWPs) in the upper troposphere ( Chang 2005 ; Wirth and Eichhorn 2014 ). This suggests that the dynamics of such RWPs play an important role for the prediction of midlatitude cyclones and the associated weather, which arguably explains the recent interest in upper-tropospheric wave packets. An

Full access
Marlene Baumgart, Michael Riemer, Volkmar Wirth, Franziska Teubler, and Simon T. K. Lang

1. Introduction Numerical weather prediction has improved remarkably over the last decades (e.g., Bauer et al. 2015 ). Occasionally, however, very poor medium-range forecasts do still occur ( Rodwell et al. 2013 ). Forecast errors arise due to errors in the initial conditions and due to model deficiencies (e.g., Palmer and Hagedorn 2006 ). After 1–2 forecast days, localized errors may form that start to affect the synoptic-scale flow (e.g., Davies and Didone 2013 ; Martínez-Alvarado et al

Open access