 |
| Titel |
A statistical study of Weinmannia pollen trajectories across the Andes |
| VerfasserIn |
C. F. Pérez, M. E. Castañeda, M. I. Gassmann, M. M. Bianchi |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7340
|
| Digitales Dokument |
URL |
| Erschienen |
In: 4th EGU Alexander von Humboldt Conference "The Andes: Challenge for Geosciences" ; Nr. 22 (2009-10-13), S.79-84 |
| Datensatznummer |
250014732
|
| Publikation (Nr.) |
 copernicus.org/adgeo-22-79-2009.pdf |
|
|
|
|
|
| Zusammenfassung |
| Recent airborne pollen records data from Northern Patagonia (San Carlos de
Bariloche, Argentina, Lat. 41.1435° S, Long. 71.375° W, 800 m elevation)
suggest that pollen transport takes place from the west to the east slope of
the Andes. However, the atmospheric characteristics responsible of this
transport have not yet been studied. The aim of this paper is to assess
potential source areas and to describe the involved atmospheric mechanisms
of the trans-Andean pollen transport. Methodology relies on the analysis of
backward trajectories of air masses calculated with the HYSPLIT 4.9 regional
model for particular days where airborne pollen of Weinmannia trichosperma Cav. was detected east
of the Andes. This pollen type was selected because it is found regularly at
localities in eastern Patagonia beyond its present-day distribution.
Weinmannia's substantial presence during early Holocene times would also benefit from
better knowledge of its transport mechanisms. Correspondence between
atmospheric trajectories and the position of sources was checked using GIS
maps. Mode T, Principal Component Analysis (PCA) with Varimax rotation was
used to identify the main spatial structure of geopotential height anomalies
producing the calculated trajectories. Eighty-eight cases showed that the
calculated directions of trajectories trended from the Northwest to
Southwest passing over the Chilean region of W. trichosperma distribution. PCs results
showed two patterns of negative anomalies over southern Patagonia. The
prevailing circulation pattern which drives airborne transport is the
presence of a trough located south of 37 to 40° S with its axis over
western Patagonia. The synoptic situations for two cases highly correlated
with principal component scores were described. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|