@Article{BakerGGMBRNAS:2021:SpPaSe,
author = "Baker, Jessica C. A. and Garcia Carreras, Luis and Gloor, Manuel
and Marsham, John H. and Buermann, Wolfgang and Rocha, Humberto R.
da and Nobre, Antonio Donato and Ara{\'u}jo, Alessandro Carioca
de and Spracklen, Dominick V.",
affiliation = "{University of Leeds} and {University of Manchester} and
{University of Leeds} and {University of Leeds} and
{Universit{\"a}t Augsburg} and {Universidade de S{\~a}o Paulo
(USP)} and {Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Empresa Brasileira de Pesquisa Agropecu{\'a}ria (EMBRAPA)} and
{University of Leeds}",
title = "Evapotranspiration in the Amazon: spatial patterns, seasonality,
and recent trends in observations, reanalysis, and climate
models",
journal = "Hydrology and Earth System Sciences",
year = "2021",
volume = "25",
number = "4",
pages = "2279--2300",
month = "Apr.",
abstract = "Water recycled through transpiring forests influences the spatial
distribution of precipitation in the Amazon and has been shown to
play a role in the initiation of the wet season. However, due to
the challenges and costs associated with measuring
evapotranspiration (ET) directly and high uncertainty in
remote-sensing ET retrievals, the spatial and temporal patterns in
Amazon ET remain poorly understood. In this study, we estimated ET
over the Amazon and 10 sub-basins using a catchment-balance
approach, whereby ET is calculated directly as the balance between
precipitation, runoff, and change in groundwater storage. We
compared our results with ET from remote-sensing datasets,
reanalysis, models from Phase 5 and Phase 6 of the Coupled Model
Intercomparison Projects (CMIP5 and CMIP6 respectively), and in
situ flux tower measurements to provide a comprehensive overview
of current understanding. Catchment-balance analysis revealed a
gradient in ET from east to west/southwest across the Amazon
Basin, a strong seasonal cycle in basin-mean ET primarily
controlled by net incoming radiation, and no trend in ET over the
past 2 decades. This approach has a degree of uncertainty, due to
errors in each of the terms of the water budget; therefore, we
conducted an error analysis to identify the range of likely
values. Satellite datasets, reanalysis, and climate models all
tended to overestimate the magnitude of ET relative to
catchment-balance estimates, underestimate seasonal and
interannual variability, and show conflicting positive and
negative trends. Only two out of six satellite and model datasets
analysed reproduced spatial and seasonal variation in Amazon ET,
and captured the same controls on ET as indicated by
catchment-balance analysis. CMIP5 and CMIP6 ET was inconsistent
with catchment-balance estimates over all scales analysed.
Overall, the discrepancies between data products and models
revealed by our analysis demonstrate a need for more ground-based
ET measurements in the Amazon as well as a need to substantially
improve model representation of this fundamental component of the
Amazon hydrological cycle.",
doi = "10.5194/hess-25-2279-2021",
url = "http://dx.doi.org/10.5194/hess-25-2279-2021",
issn = "1027-5606",
language = "en",
targetfile = "baker_evapotranspiration.pdf",
urlaccessdate = "20 maio 2024"
}