Matches in SemOpenAlex for { <https://semopenalex.org/work/W2055754058> ?p ?o ?g. }
- W2055754058 abstract "[1] Reflectance measurements from the spaceborne Polarization and Directionality of Earth Reflectances (POLDER) instrument are used to analyze the so-called hot spot directional signature in the backscattering direction. The hot spot is measured with an angular resolution better than half a degree using the directional capabilities of the radiometer, with some assumptions on the spatial homogeneity of the surface. The analysis yields the first quantitative observation of the hot spot signature of vegetated surfaces, with such angular resolution. The measurements show that the hot spot reflectance is a function of the phase angle ξ rather than a function of a parameter Δ, often used in hot spot modeling, that quantifies the horizontal distance between Sun and view directions. The observed directional signature is very accurately fitted by a linear ratio of the phase angle, as predicted by a simple theory of radiative transfer within the canopy foliage. Most of the measured hot spot half widths are between 1° and 2°. Some dispersion occurs for the cases belonging to the forest and desert International Geosphere-Biosphere Program (IGBP) classes, in the range 1° to 5°. Theory predicts that the width is independent of wavelength. Our measurements indicate that the widths at 670 and 865 nm are very close, but with a significant scatter in regards to the rather small variability. The distribution of the width as a function of the IGBP surface classification shows a variability within the classes that is larger than between the classes, except for the “evergreen broadleaf” class. The hot spot reflectance amplitude is generally on the order of 0.10–0.20 at 865 nm and 0.03–0.18 at 670 nm, although the full range of values is wider. For thick canopies, it may be interpreted in terms of foliage element (leaf) reflectance. Retrieved values are on the order of 0.4 in the near infrared and in the range 0.05–0.20 at 670 nm. At 440 nm, the amplitude of the signature is very small, as is expected from the small surface reflectance. This confirms that the atmospheric contribution to the reflectance increase at the backscattering direction is negligible." @default.
- W2055754058 created "2016-06-24" @default.
- W2055754058 creator A5057569278 @default.
- W2055754058 date "2002-01-01" @default.
- W2055754058 modified "2023-10-15" @default.
- W2055754058 title "Analysis of hot spot directional signatures measured from space" @default.
- W2055754058 cites W1546062067 @default.
- W2055754058 cites W1967150870 @default.
- W2055754058 cites W1974175105 @default.
- W2055754058 cites W1974423938 @default.
- W2055754058 cites W1977079104 @default.
- W2055754058 cites W1983142039 @default.
- W2055754058 cites W2009867302 @default.
- W2055754058 cites W2036421234 @default.
- W2055754058 cites W2044135054 @default.
- W2055754058 cites W2047068281 @default.
- W2055754058 cites W2048366450 @default.
- W2055754058 cites W2056078108 @default.
- W2055754058 cites W2056230898 @default.
- W2055754058 cites W2060827275 @default.
- W2055754058 cites W2066612219 @default.
- W2055754058 cites W2068799738 @default.
- W2055754058 cites W2071187938 @default.
- W2055754058 cites W2080110125 @default.
- W2055754058 cites W2102970817 @default.
- W2055754058 cites W2118279913 @default.
- W2055754058 cites W2125763679 @default.
- W2055754058 cites W2131669269 @default.
- W2055754058 cites W2132926714 @default.
- W2055754058 cites W2150021548 @default.
- W2055754058 cites W2152424523 @default.
- W2055754058 cites W2170494824 @default.
- W2055754058 cites W2175780936 @default.
- W2055754058 doi "https://doi.org/10.1029/2001jd001094" @default.
- W2055754058 hasPublicationYear "2002" @default.
- W2055754058 type Work @default.
- W2055754058 sameAs 2055754058 @default.
- W2055754058 citedByCount "88" @default.
- W2055754058 countsByYear W20557540582012 @default.
- W2055754058 countsByYear W20557540582013 @default.
- W2055754058 countsByYear W20557540582014 @default.
- W2055754058 countsByYear W20557540582015 @default.
- W2055754058 countsByYear W20557540582016 @default.
- W2055754058 countsByYear W20557540582017 @default.
- W2055754058 countsByYear W20557540582018 @default.
- W2055754058 countsByYear W20557540582019 @default.
- W2055754058 countsByYear W20557540582020 @default.
- W2055754058 countsByYear W20557540582021 @default.
- W2055754058 countsByYear W20557540582022 @default.
- W2055754058 countsByYear W20557540582023 @default.
- W2055754058 crossrefType "journal-article" @default.
- W2055754058 hasAuthorship W2055754058A5057569278 @default.
- W2055754058 hasBestOaLocation W20557540581 @default.
- W2055754058 hasConcept C105795698 @default.
- W2055754058 hasConcept C108597893 @default.
- W2055754058 hasConcept C111919701 @default.
- W2055754058 hasConcept C120189094 @default.
- W2055754058 hasConcept C120665830 @default.
- W2055754058 hasConcept C121332964 @default.
- W2055754058 hasConcept C127313418 @default.
- W2055754058 hasConcept C142259097 @default.
- W2055754058 hasConcept C151596937 @default.
- W2055754058 hasConcept C180205008 @default.
- W2055754058 hasConcept C199390426 @default.
- W2055754058 hasConcept C199672914 @default.
- W2055754058 hasConcept C205372480 @default.
- W2055754058 hasConcept C30475298 @default.
- W2055754058 hasConcept C33923547 @default.
- W2055754058 hasConcept C39432304 @default.
- W2055754058 hasConcept C41008148 @default.
- W2055754058 hasConcept C6260449 @default.
- W2055754058 hasConcept C62649853 @default.
- W2055754058 hasConcept C74902906 @default.
- W2055754058 hasConceptScore W2055754058C105795698 @default.
- W2055754058 hasConceptScore W2055754058C108597893 @default.
- W2055754058 hasConceptScore W2055754058C111919701 @default.
- W2055754058 hasConceptScore W2055754058C120189094 @default.
- W2055754058 hasConceptScore W2055754058C120665830 @default.
- W2055754058 hasConceptScore W2055754058C121332964 @default.
- W2055754058 hasConceptScore W2055754058C127313418 @default.
- W2055754058 hasConceptScore W2055754058C142259097 @default.
- W2055754058 hasConceptScore W2055754058C151596937 @default.
- W2055754058 hasConceptScore W2055754058C180205008 @default.
- W2055754058 hasConceptScore W2055754058C199390426 @default.
- W2055754058 hasConceptScore W2055754058C199672914 @default.
- W2055754058 hasConceptScore W2055754058C205372480 @default.
- W2055754058 hasConceptScore W2055754058C30475298 @default.
- W2055754058 hasConceptScore W2055754058C33923547 @default.
- W2055754058 hasConceptScore W2055754058C39432304 @default.
- W2055754058 hasConceptScore W2055754058C41008148 @default.
- W2055754058 hasConceptScore W2055754058C6260449 @default.
- W2055754058 hasConceptScore W2055754058C62649853 @default.
- W2055754058 hasConceptScore W2055754058C74902906 @default.
- W2055754058 hasIssue "D16" @default.
- W2055754058 hasLocation W20557540581 @default.
- W2055754058 hasLocation W20557540582 @default.
- W2055754058 hasLocation W20557540583 @default.
- W2055754058 hasLocation W20557540584 @default.
- W2055754058 hasOpenAccess W2055754058 @default.
- W2055754058 hasPrimaryLocation W20557540581 @default.