Tagging moisture sources with Lagrangian and inertial tracers: application to intense atmospheric river events
Pérez Muñuzuri, Vicente; Eiras Barca, Jorge; Garaboa Paz, Ángel Daniel
- Published
- 2018-06-08
- Publisher
- Copernicus Publications
- Language
- en
Abstract
Two Lagrangian tracer tools are evaluated for studies on atmospheric moisture sources and pathways. In these methods, a moisture volume is assigned to each particle, which is then advected by the wind flow. Usual Lagrangian methods consider this volume to remain constant and the particle to follow flow path lines exactly. In a different approach, the initial moisture volume can be considered to depend on time as it is advected by the flow due to thermodynamic processes. In this case, the tracer volume drag must be taken into account. Equations have been implemented and moisture convection was taken into account for both Lagrangian and inertial models. We apply these methods to evaluate the intense atmospheric rivers that devastated (i) the Pacific Northwest region of the US and (ii) the western Iberian Peninsula with flooding rains and intense winds in early November 2006 and 20 May 1994, respectively. We note that the usual Lagrangian method underestimates moisture availability in the continent, while active tracers achieve more realistic results
Full text
Supplement of Earth Syst. Dynam., 9, 785–795, 2018 https://doi.org/10.5194/esd-9-785-2018-supplement © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. Supplement of Tagging moisture sources with Lagrangian and inertial tracers: application to intense atmospheric river events Vicente Pérez-Muñuzuri et al. Correspondence to: Vicente Pérez-Muñuzuri ([email protected]) The copyright of individual parts of the supplement might differ from the CC BY 4.0 License.
Figures S1 and S2 show the daily mean of the precipitation rate for the 2006 and 1994 events respectively. These figures underscore the fact that the bulk of precipitation is located besides the warm sector of the cyclone, close to the leading edge of the associated AR. Figures S3 and S4 show the daily mean of the 500 hPa geopotential height. These figures underscore the fact that both the deepening of both cyclones are leaded by a low-pressure trough in the upper levels. Figure S1: Surface daily precipitation rate in mm/day for the 2006 event throughout the life of the cyclone until the landfall event. Figure S2: Surface daily precipitation rate in mm/day for the 1994 event throughout the life of the cyclone until the landfall event. 1
Figure S3: 500 hPa geopotential height in m for the 2006 event throughout the life of the cyclone until the landfall event. 2
Figure S4: 500 hPa geopotential height in m for the 1994 event throughout the life of the cyclone until the landfall event. 3
