Journal ArticleDOI
Methodology for the estimation of terrestrial net primary production from remotely sensed data
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TLDR
In this paper, the authors used the remote sensing of crop growth to estimate continental net primary productivity (NPP) as well as its seasonal and spatial variations, assuming a decomposition of NPP into independent parameters such as incident solar radiation, radiation absorption efficiency by canopies, and conversion efficiency of absorbed radiation into organic dry matter.Abstract:
Kumar and Monteith's (1981) model for the remote sensing of crop growth has been used to estimate continental net primary productivity (NPP) as well as its seasonal and spatial variations. The model assumes a decomposition of NPP into independent parameters such as incident solar radiation (S0), radiation absorption efficiency by canopies (ƒ), and conversion efficiency of absorbed radiation into organic dry matter (e). The precision on some of the input parameters has been improved, compared to previous uses of this model at a global scale: remote sensing data used to derive ƒ have been calibrated, corrected of some atmospheric effects, and filtered; e has been considered as biome-dependent and derived from literature data. The resulting global NPP (approximatively 60 GtC per year) is within the range of values given in the literature. However, mean NPP estimates per biome do not agree with the literature (in particular, the estimation for tropical rain forests NPP is much lower and for cultivations much higher than field estimates), which results in zonal and seasonal variations of continental NPP giving more weight to the temperate northern hemisphere than to the equatorial zone.read more
Citations
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Journal ArticleDOI
Primary Production of the Biosphere: Integrating Terrestrial and Oceanic Components
TL;DR: Integrating conceptually similar models of the growth of marine and terrestrial primary producers yielded an estimated global net primary production of 104.9 petagrams of carbon per year, with roughly equal contributions from land and oceans.
Journal ArticleDOI
TIMESAT - a program for analyzing time-series of satellite sensor data
Per Jönsson,Lars Eklundh +1 more
TL;DR: In this article, three different least-squares methods for processing time-series of satellite sensor data are presented, one of which uses local polynomial functions and can be classified as an adaptive Savitzky-Golay filter.
Journal ArticleDOI
Improvements of the MODIS terrestrial gross and net primary production global data set
TL;DR: In this article, a reprocessing key inputs to MODIS primary vegetation productivity algorithm, resulting in improved Collection5-MOD17 (here denoted as C5 MOD17) estimates.
Book Chapter
The Carbon Cycle and Atmospheric Carbon Dioxide
Iain Colin Prentice,Graham D. Farquhar,Mjr Fasham,Michael L. Goulden,Martin Heimann,VJ Jaramillo,Haroon S. Kheshgi,C. Le Quéré,Robert J. Scholes,D. W. R. Wallace +9 more
TL;DR: Contributing Authors D.R.A. Archer, M.M.P. Keeling, D.D.F. Weirig, T. Whorf, A.C. Sitch, R.J. Rayner, S.Q. Tans, H. Yool.
Journal ArticleDOI
Direct and Indirect Estimation of Leaf Area Index, fAPAR, and Net Primary Production of Terrestrial Ecosystems
TL;DR: In this paper, a review of direct and indirect methods used to estimate leaf area index (L), fraction of absorbed photosynthetically active radiation (fAPAR), and net primary production (NPP) from remotely sensed products is presented.
References
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Climate and the efficiency of crop production in Britain
TL;DR: The efficiency of crop production is defined in thermodynamic terms as the ratio of energy output (carbohydrate) to energy input (solar radiation). Temperature and water supply are the main climatic constraints on efficiency as mentioned in this paper.
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Characteristics of maximum-value composite images from temporal AVHRR data
TL;DR: In this paper, satellite data from the Advanced Very High Resolution Radiometer sensor have been processed over several days and combined to produce spatially continuous cloud-free imagery over large areas with sufficient temporal resolution to study green-vegetation dynamics.
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Solar radiation and productivity in tropical ecosystems
TL;DR: Conventional estimates of efficiency in terms of the amount of solar radiation incident at the earth's surface provide ecologists and agronomists with a method for comparing plant productivity under different systems of land use and management and in different * Opening paper read at IBP/UNESCO Meeting on Productivity of Tropical Ecosystems.
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Canopy reflectance, photosynthesis and transpiration
TL;DR: In this paper, a two-stream approximation model of radiative transfer was used to calculate values of hemispheric canopy reflectance in the visible and near-infrared wavelength intervals.
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Observational contrains on the global atmospheric co2 budget.
TL;DR: The observed differences between the partial pressure of CO2 in the surface waters of the Northern Hemisphere and the atmosphere are too small for the oceans to be the major sink of fossil fuel CO2, and a large amount of the CO2 is apparently absorbed on the continents by terrestrial ecosystems.