TITLE

Interaction between Dynamics and Cloud Microphysics in Orographic Precipitation Enhancement: A High-Resolution Modeling Study of Two North Alpine Heavy-Precipitation Events

AUTHOR(S)
Zängl, Günther
PUB. DATE
August 2007
SOURCE
Monthly Weather Review;Aug2007, Vol. 135 Issue 8, p2817
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Interactions of atmospheric dynamics and cloud microphysics with the Alpine orography are investigated for two north Alpine heavy-precipitation cases (20–22 May 1999 and 22–23 August 2005). Both cases were related to a deep cyclone propagating slowly eastward along the Alps, advecting moist air of Mediterranean origin toward the northern side of the Alps. A validation against high-resolution rain gauge data reveals that the average model bias is below 15% in the region of interest, but there is a tendency to systematically underestimate very heavy precipitation. A scale decomposition of the discrepancies between model and observations reveals that errors on the meso-β-scale contribute at least as much to the total model error as discrepancies on the meso-γ-scale. On the scale of single mountain ridges and valleys, the formation of precipitation maxima at valley locations is investigated, with particular emphasis on a region in which a valley receives systematically more precipitation than the adjacent mountain ridges. It is found that the downstream advection of precipitation hydrometeors generated in an orographic feeder cloud is essential for the development of valley maxima. Strong ambient winds and (due to the fall speed difference between snow/graupel and rain) a low freezing level favor a large distance of the precipitation maximum from the upstream mountain ridge. Under suitable geometrical conditions, downstream advection of hydrometeors can even lead to systematically more precipitation in the valley than over the adjacent ridges. Another mechanism capable of generating a systematic rainfall maximum at valley locations requires a freezing level between valley bottom and crest height and a mountain wave flow penetrating into the valley. Under such conditions, the increase in the fall velocity related to melting of snow or graupel into rain leads to a locally intensified fallout of hydrometeors and thus to a maximum in the precipitation rate.
ACCESSION #
26491063

 

Related Articles

  • Precipitation and microphysical studies with a low cost high resolution X-band radar: an innovative project prospective. Baelen, J. Van; Pointin, Y.; Wobrock, W.; Flossmann, A.; Peters, G.; Tridon, F.; Planche, C. // Advances in Geosciences;2009, Vol. 20, p25 

    This paper describes an innovative project which has just been launched at the "Laboratoire de Météorologie Physique" (LaMP) in Clermont-Ferrand in collaboration with the "Meteorologische Institut" in Hamburg, where a low cost X-band high resolution precipitation radar is combined with...

  • In search for relationships between lightning and rainfall with a rectangular grid-box methodology. Michaelides, S. C.; Savvidou, K.; Nicolaides, K. A.; Charalambous, M. // Advances in Geosciences;2009, Vol. 20, p51 

    The rainfall and lightning activity associated with three depressions which affected the area of Cyprus were studied in order to identify possible relationships between them. The lightning data were provided by the National Observatory of Athens, Greece, and were spatially and statistically...

  • The Varying Response of Microwave Signatures to Different Types of Overland Rainfall Found over the Korean Peninsula. Eun-Kyoung Seo; Guosheng Liu; Myoung-Seok Suh; Byung-Ju Sohn // Journal of Atmospheric & Oceanic Technology;Apr2010, Vol. 27 Issue 4, p785 

    The Tropical Rainfall Measuring Mission (TRMM) precipitation radar and ground rain measurements were used to investigate the performance of the TRMM Microwave Imager (TMI) land algorithm. In particular, data from a dense network of rain gauges being operated over the Korean Peninsula were...

  • The Diurnal Cycle of Rainfall and Convective Intensity according to Three Years of TRMM Measurements. Nesbitt, Stephen W.; Zipser, Edward J. // Journal of Climate;May2003, Vol. 16 Issue 10, p1456 

    The Tropical Rainfall Measuring Mission (TRMM) satellite measurements from the precipitation radar and TRMM microwave imager have been combined to yield a comprehensive 3-yr database of precipitation features (PFs) throughout the global Tropics (±36° latitude). The PFs retrieved using this...

  • Distribuição das chuvas no município de Tangará da Serra, médio norte do Estado de Mato Grosso, Brasil. Dallacort, Rivanildo; Martins^2, Juliano Araujo; Inoue, Miriam Hiroko; Lourenço de Freitas, Paulo Sergio; Coletti, Ademar Junior // Acta Scientiarum: Agronomy;Apr-Jun2011, Vol. 33 Issue 2, p193 

    It is of great importance to know the rain distribution in the region of Tangará da Serra (latitude 14°37′55″S, longitude 57°28′05″W and altitude 488 m), as it is an agricultural region, which makes such information essential for an adequate planning,...

  • Comparison of rain gauge observations with modeled precipitation over Cyprus using Contiguous Rain Area analysis. Tartaglione, N.; Mariani, S.; Accadia, C.; Speranza, A.; Casaioli, M. // Atmospheric Chemistry & Physics;2005, Vol. 5 Issue 10, p2147 

    Verification of modeled rainfall with precipitation observed by a rain gauge network has been performed in a case study over the Cyprus Island. Cyprus has a relatively dense rain gauge network. The applied verification method is the Contiguous Rain Area (CRA) analysis. Some drawbacks of the CRA...

  • Subpixel-Scale Rainfall Variability and the Effects on Separation of Radar and Gauge Rainfall Errors. Zhang, Yu; Adams, Thomas; Bonta, James V. // Journal of Hydrometeorology;Dec2007, Vol. 8 Issue 6, p1348 

    This paper presents an extended error variance separation method (EEVS) that allows explicit partitioning of the variance of the errors in gauge- and radar-based representations of areal rainfall. The implementation of EEVS demonstrated in this study combines a kriging scheme for estimating...

  • Analysis of precipitation characteristics of Poyang Lake Basin. CAO Yanhua; YE Xiaofeng; LV Guanghong // Applied Mechanics & Materials;2014, Issue 630-642, p29 

    This paper was based on the Poyang lake Basin's 55a rainfall data (1959 ∼2014). First, the recursive linear interpolation method was used to complete the daily precipitation observation data of 55a to establish the Poyang lake basin's data. Then the linear regression method was used to...

  • A Method for Evaluating the Accuracy of Quantitative Precipitation Estimates from a Hydrologic Modeling Perspective. Gourley, Jonathan J.; Vieux, Baxter E. // Journal of Hydrometeorology;Apr2005, Vol. 6 Issue 2, p115 

    A major goal in quantitative precipitation estimation and forecasting is the ability to provide accurate initial conditions for the purposes of hydrologic modeling. The accuracy of a streamflow prediction system is dependent upon how well the initial hydrometeorological states are characterized....

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics