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Amazon rainforests green-up with sunlight in dry season

Alfredo R. Huete, Kamel Didan, Yosio E. Shimabukuro, Piyachat Ratana, Scott R. Saleska, Lucy R. Hutyra, Wenze Yang, Ramakrishna R. Nemani, Ranga Myneni
2006 Geophysical Research Letters  
MODIS Enhanced Vegetation Index (EVI, an index of canopy photosynthetic capacity) increased by 25% with sunlight during the dry season across Amazon forests, opposite to ecosystem model predictions that  ...  1] Metabolism and phenology of Amazon rainforests significantly influence global dynamics of climate, carbon and water, but remain poorly understood.  ...  We thank Andrew Jacobson with help on CMG analysis and David Fitzjarrald and Ricardo Sakai for the pasture/agriculture site flux tower data.  ... 
doi:10.1029/2005gl025583 fatcat:7ysungallrbkjj37yfklz6sqyq

Climatic factors driving vegetation declines in the 2005 and 2010 Amazon droughts

Wenqian Zhao, Xiang Zhao, Tao Zhou, Donghai Wu, Bijian Tang, Hong Wei, Gil Bohrer
2017 PLoS ONE  
index responses of 0-4, 0-9 and 0-6 months, respectively; (ii) on average, the three climatic factors without time lags explained 27.28±21.73% (mean±1 SD) of vegetation index variation in the Amazon basin  ...  This study aims to explore the climate-driven factors of Amazonian vegetation decline during the extreme droughts using vegetation index, precipitation, temperature and radiation datasets.  ...  Dry season lengths differ greatly across the Amazon, from 0 to 5 months, roughly consistent with the distribution of annual mean rainfall [28] .  ... 
doi:10.1371/journal.pone.0175379 pmid:28426691 pmcid:PMC5398491 fatcat:txe35abheffudgwq6u3wqanpde

Vegetation dynamics and rainfall sensitivity of the Amazon

Thomas Hilker, Alexei I. Lyapustin, Compton J. Tucker, Forrest G. Hall, Ranga B. Myneni, Yujie Wang, Jian Bi, Yhasmin Mendes de Moura, Piers J. Sellers
2014 Proceedings of the National Academy of Sciences of the United States of America  
We show that the vegetation canopy of the Amazon rainforest is highly sensitive to changes in precipitation patterns and that reduction in rainfall since 2000 has diminished vegetation greenness across  ...  Large-scale directional declines in vegetation greenness may indicate decreases in carbon uptake and substantial changes in the energy balance of the Amazon.  ...  This work was supported by the Science of Terra and Aqua Program of NASA (A.I.L. and Y.W.).  ... 
doi:10.1073/pnas.1404870111 pmid:25349419 pmcid:PMC4234539 fatcat:wauxakh3bnfirfzmahl5xe67xq

Widespread decline in greenness of Amazonian vegetation due to the 2010 drought

Liang Xu, Arindam Samanta, Marcos H. Costa, Sangram Ganguly, Ramakrishna R. Nemani, Ranga B. Myneni
2011 Geophysical Research Letters  
The greenness data consisted of Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra satellite  ...  Plant-available soil moisture data across the wide Amazon basin are not available to assess the spatial extent and impacts of droughts here.  ... 
doi:10.1029/2011gl046824 fatcat:d5qhx3p4tfc7xjvqwiryccqznu

Asynchronous Response of Tropical Forest Leaf Phenology to Seasonal and El Niño-Driven Drought

Stephanie Pau, Gregory S. Okin, Thomas W. Gillespie, Jerome Chave
2010 PLoS ONE  
We use satellitederived Normalized Difference Vegetation Index (NDVI) from February 2000-February 2009 to show that rainforests and dry forests in the Hawaiian Islands exhibit asynchronous responses in  ...  The spatial pattern of NDVI response to the NINO 3.4 Sea Surface Temperature (SST) index during [2002][2003] showed that the leeward side exhibited significant negative correlations to increased SSTs,  ...  Author Contributions Conceived and designed the experiments: SP GSO TWG. Performed the experiments: SP GSO TWG. Analyzed the data: SP GSO TWG.  ... 
doi:10.1371/journal.pone.0011325 pmid:20593034 pmcid:PMC2892520 fatcat:d6kccjnkbbhlfaoketykm3ixg4

Regulated large-scale annual shutdown of Amazonian isoprene emissions?

Michael P. Barkley, Paul I. Palmer, Isabelle De Smedt, Thomas Karl, Alex Guenther, Michel Van Roozendael
2009 Geophysical Research Letters  
However, unusually low HCHO columns are consistently observed over the Amazon rainforest during the transition from the wet-to-dry seasons.  ...  We use MODIS leaf area and enhanced vegetation indices, to show variations in vegetation are consistent with the observed decrease in HCHO during this period (correlations of 0.69 and 0.67, respectively  ...  We thank Randall Martin for providing GOME/SCIAMACHY NO 2 data and the ESA portal for the ATSR firecounts.  ... 
doi:10.1029/2008gl036843 fatcat:axe4ggnmknedteoidddkeiurke

Comparison of satellite-derived LAI and precipitation anomalies over Brazil with a thermal infrared-based Evaporative Stress Index for 2003–2013

Martha C. Anderson, Cornelio A. Zolin, Christopher R. Hain, Kathryn Semmens, M. Tugrul Yilmaz, Feng Gao
2015 Journal of Hydrology  
rainforested regions of the Amazon basin which are subject to prolonged periods of cloud cover and episodes of intense biomass burning.  ...  s u m m a r y Shortwave vegetation index (VI) and leaf area index (LAI) remote sensing products yield inconsistent depictions of biophysical response to drought and pluvial events that have occurred in  ...  Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial  ... 
doi:10.1016/j.jhydrol.2015.01.005 fatcat:mqgztz6nvfgddcgcbbxj2vjtim

Effects of Warming and Drought on the Vegetation and Plant Diversity in the Amazon Basin

Ingrid Olivares, Jens-Christian Svenning, Peter M. van Bodegom, Henrik Balslev
2015 The Botanical review  
Climate change is strong in the Amazon basin. Climate models consistently predict widespread warmer and drier conditions by the end of the 21 st century.  ...  We here review current understanding of the impact of climate change on forests' distribution patterns, species diversity and ecosystem functioning of lowland rainforests in the Amazon basin.  ...  One study compared the effect of dry season length by comparing two seasonal forests in the eastern Amazon basin .  ... 
doi:10.1007/s12229-014-9149-8 fatcat:7g5r77avejbsvjdwvs5xr3sfhm

Reassessing climate and pre-Columbian drivers of paleofire activity in the Bolivian Amazon

S. Yoshi Maezumi, Bronwen S. Whitney, Francis E. Mayle, Jonas Gregorio de Souza, Jose Iriarte
2018 Quaternary International  
The simultaneous increase in fire activity with the expansion of the less flammable humid rainforest vegetation suggests human fire management practices.  ...  These data are interpreted as the use of frequent, low severity, human-caused fires to clear the croplands from encroaching rainforest vegetation.  ...  ) from the village of Florida for assistance with coring the site.  ... 
doi:10.1016/j.quaint.2017.11.053 fatcat:gpixcvg3nja2fblrrvbxwifydu

Responses of Amazonian ecosystems to climatic and atmospheric carbon dioxide changes since the last glacial maximum

F. E. Mayle, D. J. Beerling, W. D. Gosling, M. B. Bush
2004 Philosophical Transactions of the Royal Society of London. Biological Sciences  
Cold-adapted Andean taxa mixed with rainforest taxa in central areas, while dry forest species and lianas probably became important in the more seasonal southern Amazon forests and savannahs expanded at  ...  Rainforests expanded once more in the Late Holocene owing to increased precipitation caused by greater austral summer insolation, although some of this forest expansion (e.g. in parts of the Bolivian Beni  ...  Natural 'Noel Kempff Mercado' for logistical field support for F.E.M.; the University of Leicester for a sabbatical for F.E.M. and a PhD studentship for W.D.G.; R.  ... 
doi:10.1098/rstb.2003.1434 pmid:15212099 pmcid:PMC1693334 fatcat:gws4lk7lh5haxj45fp5n7wa3lm

Towards quantifying uncertainty in predictions of Amazon 'dieback'

C. Huntingford, R. A Fisher, L. Mercado, B. B.B Booth, S. Sitch, P. P Harris, P. M Cox, C. D Jones, R. A Betts, Y. Malhi, G. R Harris, M. Collins (+1 others)
2008 Philosophical Transactions of the Royal Society of London. Biological Sciences  
The potential for human-induced climate change to trigger the loss of Amazon rainforest appears robust within the context of the uncertainties explored in this paper.  ...  We find that the loss of Amazonian rainforest is robust across the climate uncertainty explored by perturbed physics simulations covering a wide range of global climate sensitivity.  ...  (including a dynamic global vegetation model (DGVM)) predicts that climate change could cause a major loss of the Amazon rainforest .  ... 
doi:10.1098/rstb.2007.0028 pmid:18267905 pmcid:PMC2374898 fatcat:4hnxtk3f6nef3iybyjam5uetu4

Amazon vegetation greenness as measured by satellite sensors over the last decade

P. M. Atkinson, J. Dash, C. Jeganathan
2011 Geophysical Research Letters  
We analysed 11 years of dry season (July-September) Moderate Resolution Imaging Spectroradiometer (MODIS) enhanced vegetation index (EVI) and normalised difference vegetation index (NDVI) images.  ...  Several studies have claimed the ability to detect the effect of these droughts on Amazon vegetation response, measured through satellite sensor vegetation indices (VIs).  ...  Authors are grateful to Geography and Environment Academic Unit, University of Southampton for funding.  ... 
doi:10.1029/2011gl049118 fatcat:fy5lnoqp2fghrmy62tip4r2bsi

Vegetation and Fire at the Last Glacial Maximum in Tropical South America [chapter]

Francis E. Mayle, Michael J. Burn, Mitchell Power, Dunia H. Urrego
2009 Developments in Paleoenvironmental Research  
rainforest and gallery forest at the Amazon basin margins.  ...  This chapter aims to review current knowledge of the key vegetation types, and their composition, structure, distribution, and fire regime across the South American tropics during the global Last Glacial  ...  Acknowledgments We thank Francoise Vimeux and Florence Sylvestre for kindly inviting us to write this chapter, as well as the authors of all the records discussed here, whose research made this chapter  ... 
doi:10.1007/978-90-481-2672-9_4 fatcat:thvesuxt4ncabhynwntub62piq

Predictability of tropical vegetation greenness using sea surface temperatures

Binyan Yan, Jiafu Mao, Xiaoying Shi, Forrest M Hoffman, Michael Notaro, Tianjun Zhou, Nate McDowell, Robert E Dickinson, Min Xu, Lianhong Gu, Daniel M Ricciuto
2019 Environmental Research Communications  
This study employed fine spatial resolution remotely-sensed Enhanced Vegetation Index (EVI) and SST indices from tropical ocean basins to investigate the predictability of tropical vegetation greenness  ...  These results provide a basis for the prediction of changes in greenness of tropical terrestrial ecosystems at seasonal to intra-seasonal scales.  ...  The percentages for the three rainforests were 59.21% (Amazon), 59.80% (Congo), and 61.45% (Southeast Asia).  ... 
doi:10.1088/2515-7620/ab178a fatcat:43piiodnhrhwjarbclh4vagw4a

Estimation of Evapotranspiration of Amazon Rainforest Using the Maximum Entropy Production Method

Donghui Xu, Elizabeth Agee, Jingfeng Wang, Valeriy Y. Ivanov
2019 Geophysical Research Letters  
Different methodologies have been applied to modeling ET over the Amazon rainforest.  ...  The uncertainty of these variables can be especially large for the Amazon rainforest with high biodiversity, making it challenging to evaluate evapotranspiration in space and time.  ...  Overall, the presented analysis demonstrates the ability of the MEP model to consistently represent ET in the Amazon rainforest.  ... 
doi:10.1029/2018gl080907 fatcat:ldurvtkhjzgptivmkgv6nsnqby
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