The effects of wind forcing and Earth's rotation on the transport processes in Lake Garda (Italy) are investigated for the first time under different thermal stratification conditions and typical diurnal wind cycles. Numerical simulations are performed by means of a modeling chain composed of a meteorological (WRF) and a hydrodynamic (Delft3D) model. Transport processes are studied through the combined analysis of the residual (time averaged) flow field and the trajectories of Lagrangian particles. Results show that strong currents develop in winter under the forcing of synoptic northerly Him winds, especially in the elongated northern region, where winds are channeled by the steep orography. Significant water volumes are displaced laterally by Ekman transport, producing intense downwelling and upwelling along the steep shores. Instead summer patterns are controlled by the diurnal cycle of local breezes, alternately blowing along the main axis of the lake. The resulting circulation reveals counterclockwise gyres in the northern part, driven by the alternating wind direction and affected by Coriolis force. The analysis suggests that complex circulations can develop in lakes with relatively simple geometries, like the narrow trunk region of Lake Garda, where the effect of Earth's rotation unexpectedly influences the transport patterns.

Wind variability and Earth’s rotation as drivers of transport in a deep, elongated subalpine lake: The case of Lake Garda / Amadori, Marina; Piccolroaz, Sebastiano; Giovannini, Lorenzo; Zardi, Dino; Toffolon, Marco. - In: JOURNAL OF LIMNOLOGY. - ISSN 1129-5767. - 77:3(2018), pp. 505-521. [10.4081/jlimnol.2018.1814]

Wind variability and Earth’s rotation as drivers of transport in a deep, elongated subalpine lake: The case of Lake Garda

Amadori, Marina;Piccolroaz, Sebastiano;Giovannini, Lorenzo;Zardi, Dino;Toffolon, Marco
2018-01-01

Abstract

The effects of wind forcing and Earth's rotation on the transport processes in Lake Garda (Italy) are investigated for the first time under different thermal stratification conditions and typical diurnal wind cycles. Numerical simulations are performed by means of a modeling chain composed of a meteorological (WRF) and a hydrodynamic (Delft3D) model. Transport processes are studied through the combined analysis of the residual (time averaged) flow field and the trajectories of Lagrangian particles. Results show that strong currents develop in winter under the forcing of synoptic northerly Him winds, especially in the elongated northern region, where winds are channeled by the steep orography. Significant water volumes are displaced laterally by Ekman transport, producing intense downwelling and upwelling along the steep shores. Instead summer patterns are controlled by the diurnal cycle of local breezes, alternately blowing along the main axis of the lake. The resulting circulation reveals counterclockwise gyres in the northern part, driven by the alternating wind direction and affected by Coriolis force. The analysis suggests that complex circulations can develop in lakes with relatively simple geometries, like the narrow trunk region of Lake Garda, where the effect of Earth's rotation unexpectedly influences the transport patterns.
2018
3
Amadori, Marina; Piccolroaz, Sebastiano; Giovannini, Lorenzo; Zardi, Dino; Toffolon, Marco
Wind variability and Earth’s rotation as drivers of transport in a deep, elongated subalpine lake: The case of Lake Garda / Amadori, Marina; Piccolroaz, Sebastiano; Giovannini, Lorenzo; Zardi, Dino; Toffolon, Marco. - In: JOURNAL OF LIMNOLOGY. - ISSN 1129-5767. - 77:3(2018), pp. 505-521. [10.4081/jlimnol.2018.1814]
File in questo prodotto:
File Dimensione Formato  
Amadori_etal_JL2018.pdf

accesso aperto

Tipologia: Versione editoriale (Publisher’s layout)
Licenza: Creative commons
Dimensione 3.63 MB
Formato Adobe PDF
3.63 MB Adobe PDF Visualizza/Apri
Amadori_etal_JL2018-SI.pdf

accesso aperto

Descrizione: Supplementary material
Tipologia: Altro materiale allegato (Other attachments)
Licenza: Creative commons
Dimensione 3.67 MB
Formato Adobe PDF
3.67 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/226182
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 19
  • ???jsp.display-item.citation.isi??? 19
social impact