Observed shifts in land surface conditions during the North American Monsoon: Implications for a vegetation–rainfall feedback mechanism

The North American Monsoon (NAM) is characterized by seasonal precipitation pulses which produce a considerable impact on land surface conditions. Changes in land surface processes have received less attention among the factors that concurrently influence the NAM. In this study, we utilize remotely-...

Full description

Saved in:
Bibliographic Details
Published in:Journal of arid environments 2010-05, Vol.74 (5), p.549-555
Main Authors: Méndez-Barroso, Luis A., Vivoni, Enrique R.
Format: Article
Language:English
Subjects:
Albedo
albedo (reflectance)
arid lands
Atmospherics
Ecohydrology
Feedback
Land
Land surface temperature
Marine
Monsoons
North American Monsoon
Precipitation
rain
Remote sensing
Semiarid ecosystems
semiarid zones
shrublands
Sonoran desert
spatial variation
Spatiotemporal variability
temporal variation
Vegetation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The North American Monsoon (NAM) is characterized by seasonal precipitation pulses which produce a considerable impact on land surface conditions. Changes in land surface processes have received less attention among the factors that concurrently influence the NAM. In this study, we utilize remotely-sensed and ground-based measurements to infer land surface changes that can influence the NAM through a vegetation–rainfall feedback mechanism. Our study is focused over the period 2004–2007 in northwest Mexico. Results from the analysis of remote sensing data indicate that the ground observations at an eddy covariance tower are representative of the land surface dynamics in subtropical scrublands. The extensive subtropical scrubland region exhibits a high seasonality in vegetation greenness, albedo and land surface temperature. Given the site representativeness, an analysis of land–atmosphere observations prior to and during the NAM is used to infer the necessary conditions for a vegetation–rainfall feedback mechanism in subtropical scrublands. We find that precipitation during the monsoon onset leads to changes in vegetation that impact land surface states and fluxes. For sunny days, the land surface conditions support the existence of a positive vegetation–rainfall feedback. Persistent cloudiness arising from prior storm events, however, can weaken the feedback mechanism. The land-based inferences on the vegetation–rainfall feedback presented here need to be corroborated with regional atmospheric measurements and modeling.
ISSN:0140-1963
1095-922X
DOI:10.1016/j.jaridenv.2009.09.026