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Relation between Seasonally Detrended Shortwave Infrared Reflectance Data and Land Surface Moisture in Semi‑Arid Sahel

Jørgen Olsen, Pietro Ceccato, Simon Proud, Rasmus Fensholt, Manuela Grippa, Eric Mougin, Jonas Ardö, Inge Sandholt
2013 Remote Sensing  
In this study we explored the potential of using reflectance data in the Red, Near Infrared (NIR), and Shortwave Infrared (SWIR) spectral regions for detecting short term variations in land surface moisture  ...  We focused on responses in surface reflectance to soil-and surface moisture for bare soil and early to mid-growing season.  ...  season in semi arid Sahel.  ... 
doi:10.3390/rs5062898 fatcat:3zrbkt7hlndzjidjmb5ghwpp7u

Remote sensing of vegetation in the Sudano-Sahelian zone: A literature review from 1975 to 2014

Martin Karlson, Madelene Ostwald
2016 Journal of Arid Environments  
Scarcity of in situ vegetation data inhibits research and natural resource management in the Sudano-Sahelian zone (SSZ).  ...  changes in vegetation productivity and broad vegetation types, whereas its use for studying interactions between vegetation and environmental factors has been relatively low.  ...  The authors thank Heather Reese, Tina Neset, David Bastviken, Åsa Danielsson and Rasmus Fensholt for valuable input to the manuscript.  ... 
doi:10.1016/j.jaridenv.2015.08.022 fatcat:fvoj6zzmmnehjb6lsxmuzmeuga

Drought impacts on terrestrial primary production underestimated by satellite monitoring

Benjamin D. Stocker, Jakob Zscheischler, Trevor F. Keenan, I. Colin Prentice, Sonia I. Seneviratne, Josep Peñuelas
2019 Nature Geoscience  
Data availability P-model outputs from site-scale and global simulations are available on Zenodo at: https://doi.org/10.5281/zenodo.1423484.  ...  Local effects in semi-arid grasslands and savannahs are larger, reducing mean annual GPP by more than 50%.  ...  To remediate the drought-related bias in GPP estimates, attempts have been made to use remotely sensed surface reflectance data to estimate water availability 39,40 or to directly measure physiological  ... 
doi:10.1038/s41561-019-0318-6 fatcat:4ckwlyghsnfk3gkv34isahdkku

Deriving seasonal dynamics in ecosystem properties of semi-arid savanna grasslands from in situ-based hyperspectral reflectance

T. Tagesson, R. Fensholt, S. Huber, S. Horion, I. Guiro, A. Ehammer, J. Ardö
2015 Biogeosciences  
</strong> This paper investigates how hyperspectral reflectance (between 350 and 1800 nm) can be used to infer ecosystem properties for a semi-arid savanna grassland in West Africa using a unique in situ-based  ...  The wavelengths with the strongest correlation to seasonal dynamics in ecosystem properties were shortwave infrared (biomass), the peak absorption band for chlorophyll <i>a</i> and <i>b</i> (at 682 nm)  ...  This paper was written within the frame of the project entitled Earth Observation based Vegetation productivity and Land Degradation Trends in Global Drylands.  ... 
doi:10.5194/bg-12-4621-2015 fatcat:jvjwablmxfesrbnhz36egq4jrq

Characteristics, drivers and feedbacks of global greening

Shilong Piao, Xuhui Wang, Taejin Park, Chi Chen, Xu Lian, Yue He, Jarle W. Bjerke, Anping Chen, Philippe Ciais, Hans Tømmervik, Ramakrishna R. Nemani, Ranga B. Myneni
2019 Nature Reviews Earth & Environment  
Greening is pronounced over intensively farmed or afforested areas, such as in China and India, reflecting human activities.  ...  Coupling high temporal and fine spatial resolution remotesensing observations with ground measurements, increasing sampling in the tropics and Arctic, and modelling Earth systems in more detail will further  ...  Precipitation-driven greening is most evident in the African Sahel 93,94 and semi-arid ecosystems of southern Africa and Australia 45, 95 (Fig. 4c) .  ... 
doi:10.1038/s43017-019-0001-x fatcat:73r4t4zw4fd7bcr377oagiprmm

Evaluating the strength of the land–atmosphere moisture feedback in earth system models using satellite observation

Paul A. Levine, James T. Randerson, Sean C. Swenson, David M. Lawrence
2016 Hydrology and Earth System Sciences Discussions  
Consistent with previous studies conducted across different spatial and temporal scales, our analysis suggests that models may overestimate the strength of the feedbacks between the land surface and the  ...  In places where moisture availability limits evapotranspiration (ET), variability in TWS has the potential to influence surface energy fluxes and atmospheric conditions.  ...  Regions of strong forcing, in which the TWSA at the beginning of the drawdown interval was related to the subsequent atmospheric state, coincided with the semi-arid zones previously found to be hot spots  ... 
doi:10.5194/hess-2016-206 fatcat:3sfzgsdsmvbr7hava5whlcwjxi

Evaluating the strength of the land–atmosphere moisture feedback in Earth system models using satellite observations

Paul A. Levine, James T. Randerson, Sean C. Swenson, David M. Lawrence
2016 Hydrology and Earth System Sciences  
Consistent with previous studies conducted across different spatial and temporal scales, our analysis suggests that models may overestimate the strength of the feedbacks between the land surface and the  ...  In places where moisture availability limits evapotranspiration (ET), variability in TWS has the potential to influence surface energy fluxes and atmospheric conditions.  ...  Ford and two anonymous referees  ... 
doi:10.5194/hess-20-4837-2016 fatcat:7hvnlzufvvdgtnclx7cblhvnuy

2014 Index IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Vol. 7

2014 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
., and Foerster, S  ...  ., +, JSTARS Oct. 2014 3998-4009 Land surface Estimation of High-Resolution Land Surface Shortwave Albedo From AVIRIS Data.  ...  ., +, JSTARS June 2014 2317-2336 Analysis of the Proportion of Surface Reflected Radiance in Mid-Infrared Absorption Bands.  ... 
doi:10.1109/jstars.2015.2397347 fatcat:ib3tjwsjsnd6ri6kkklq5ov37a

Climate [chapter]

2005 A Climate Modelling Primer  
This global simulation involves a surface albedo change for a group of semi-arid areas. It can be seen that an increase in surface albedo does seem to decrease rainfall.  ...  The sparse vegetation natural to arid and semi-arid areas can be easily removed as a result of relatively minor changes in the climate or by direct influence of human activity such as overgrazing or poor  ...  It is the location of all interactions between the Earth's surface (land, ocean and ice) and the free atmosphere. Bowen ratio. The ratio of sensible heat flux to latent heat flux from a surface. BP.  ... 
doi:10.1002/0470857617.ch1 fatcat:evealdfftfba5oec3bgmjzanaa

State of the Climate in 2010

J. Blunden, D. S. Arndt, M. O. Baringer
2011 Bulletin of The American Meteorological Society - (BAMS)  
The year began and ended with very large soil moisture deficits and drought conditions in several North Island regions, and in parts of the east of the South Island.  ...  In contrast, areas of Northland, Auckland and Waikato, Otago, the Lakes District, and parts of the West Coast and Buller recorded below normal annual rainfall totals (between 50% and 79% of normal).  ...  Specifically, rainfall surpluses ranged between 50 mm and 100 mm across the Sahel in June and moisture was sustained throughout the season, exceeding 150 mm above average in portions of the western Sahel  ... 
doi:10.1175/1520-0477-92.6.s1 fatcat:agnb5qh3uncxnks2eefb7somse

Monsoons: Processes, predictability, and the prospects for prediction

P. J. Webster, V. O. Magaña, T. N. Palmer, J. Shukla, R. A. Tomas, M. Yanai, T. Yasunari
1998 Journal of Geophysical Research  
Precipitation data is a combined product from MSU data and surface precipitation data (D. Lawrence: Program in Atmospheric and Oceanic Sciences, University of Colorado; Boulder.  ...  et al. [1992] studied the seasonal changes in the large-scale circulation, thermal and moisture distributions over the Tibetan Plateau and surrounding areas.  ...  the University of Colorado's Program in Atmospheric and Oceanic Sciences, the Center for Ocean, Land and Atmosphere (COLA), Washington DC, and the European Centre for Medium-Range Weather Forecasts in  ... 
doi:10.1029/97jc02719 fatcat:s4fy5ekkazdnrg4dlm5qltxqo4

Vegetation - albedo - precipitation interactions in North Africa during the Holocene

F. Vamborg
2011
Using different model setups of the MPI-ESM: a land surface with and without dynamic vegetation, and with and without the new albedo scheme, the interactions between vegetation, albedo and precipitation  ...  A new land surface albedo scheme that takes the dynamic behaviour of the surface below the canopy into account, has been implemented into the land surface scheme of the Earth system model of the Max Planck  ...  In arid to semi-arid regions, the land surface albedo varies seasonally, with changes in LAI being one of the main modulators of these changes.  ... 
doi:10.17617/2.1139653 fatcat:vqlgsfj4gveqvl5ayketfp6q3m

Quantification of soil properties for analyzing surface processes using spectroscopy and laser scanning [article]

Sören-Nils Haubrock, Humboldt-Universität Zu Berlin, Humboldt-Universität Zu Berlin
2017
Soil processes taking place in the context of erosion and land degradation are highly dependent on the properties of the surface.  ...  The thesis developed a set of methods and indices that successfully implement the quantification of surface soil moisture and roughness in the field.  ...  Similar results were observed by Lobell and Asner (2002) , who found that reflectance saturated at much lower moisture contents in the visible and nearinfrared (VNIR) spectral region than in the shortwave-infrared  ... 
doi:10.18452/15986 fatcat:gyigvwtof5dynfubtmry6oymmu

The Ecohydrological Impacts of Secondary Precipitation Processes

Francois Ritter
2020
While xeric grasslands receives 1-2 dew events per week independently of air moisture levels, the dew frequency in mesic and tropical grasslands varies from 15% to 95% of dewfall per night depending on  ...  Mean annual precipitation is a major driver of terrestrial primary productivity and has exhibited long-term stationary behavior over land areas.  ...  We would like to thank Josh Roberti and Morgan Jones for providing the meta-data of the sites.  ... 
doi:10.25417/uic.13475334.v1 fatcat:utm6vtvb3zhzjetez22xs25ddi

Final Draft Chapter 3 IPCC WG1 Fourth Assessment Report Chapter 3: Observations: Surface and Atmospheric Climate Change 1 2 Coordinating Lead Authors: 3 4 6 7

Kevin Trenberth, Philip Jones, Peter Ambenje, Roxana Bojariu, David Easterling, Albert Klein Tank, David, James Parker, Fatemeh Renwick, Matilde Rahimzadeh, Brian Rusticucci, Mao Soden (+71 others)
unpublished
Acknowledgements 41 The authors would gratefully acknowledge the valuable assistance of Sara Veasey (NCDC, Asheville) and  ...  regime over the frontier across the54 semi-arid region of the La Plata Basin.  ...  The second is the availability of surface moisture, 21 which is not an issue over oceans, but which is related to soil moisture amounts over land.  ... 
fatcat:nxcpxczih5dmdde663jw56maaq
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