Metrics of scale in remote sensing and GIS

doi:10.1016/S0303-2434(01)85002-9

International Journal of Applied Earth Observation and Geoinformation

Volume 3, Issue 2, 2001, Pages 114-120

https://doi.org/10.1016/S0303-2434(01)85002-9 Get rights and content

Abstract

The term scale has many meanings, some of which survive the transition from analog to digital representations of information better than others. Specifically, the primary metric of scale in traditional cartography, the representative fraction, has no well-defined meaning for digital data. Spatial extent and spatial resolution are both meaningful for digital data, and their ratio, symbolized as L/S, is dimensionless. L/S appears confined in practice to a narrow range. The implications of this observation are explored in the context of Digital Earth, a vision for an integrated geographic information system. It is shown that despite the very large data volumes potentially involved, Digital Earth is nevertheless technically feasible with today's technology.

Résumé

Le terme échelle a plusieurs significations, dont certaines survivent la transition de représentations de l’information de l’analogique vers le numérique mieux que d’autres. En particulier, le premier système métrique d’échelle en cartographie traditionnelle, à savoir la fraction représentative n’a pas un sens bien défini pour des données numériques. Une dimension spatiale et une résolution spatiale sont toutes deux pleines de signification pour des données numériques et leur rapport, représenté par le symbole L/S, est sans dimension. En pratique L/S parait confiné dans une étendue étroite. Les implications de cette observation sont explorées dans le contexte de “Terre Numérique”, une vision pour un système d’information géographique intégré. Il est montré qu’en dépit des très grands volumes des données potentiellement concernées, une “Terre Numérique” est techniquement réalisable avec la technologie d’aujourd’hui.

Resumen

El término escala tiene muchos significados, de los cuales algunos sobreviven mejor que otros la transición entre las representaciones análogas de la información y las digitales. Específicamente, la métrica primária de la escala en cartografía tradicional, la fracción representativa, no tiene significado bien definido en el caso de datos digitales. Extensión espacial y resolución espacial tienen sentido para datos digitales, y su relación simbolizada como L/S no tiene dimensión. La relación L/S parece ser confinada en la práctica a un rango estrecho. Se exploran las implicaciones de esta observación en el contexto de Tierra Digital, una visión para un sistema integrado de información geográfica. Se muestra que, a pesar de los amplios volúmenes de datos potencialmente involucrados, Tierra Digital es tecnicamente factible con la tecnología actual.

References (6)

P.M. Atkinson
Geographical information science: Geocomputation and non-stationarity
Progress in Physical Geography
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M.F. Goodchild
Communicating geographic information in a digital age
Annals of the Association of American Geographers
(2000)
M.F. Goodchild et al.
Scale in a digital geographic world
Geographical and Environmental Modelling
(1997)

There are more references available in the full text version of this article.

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A scene can therefore be segmented at a variety of scale levels, ideally emulating the scale levels of geographical features distinguishable in that scene (Costa et al., 2018). However, the scale of segmentation outputs depends on the scale characteristics of the input imagery, namely spatial resolution and spatial extent as the most important components of the geospatial data (Goodchild, 2001). While the relationship between segmentation scale and spatial resolution has been relatively well addressed, the impact of spatial extent on segmentation results has been basically ignored.
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Metrics of scale in remote sensing and GIS

Abstract

Résumé

Resumen

Geographical information science: Geocomputation and non-stationarity

Progress in Physical Geography

Communicating geographic information in a digital age

Annals of the Association of American Geographers

Scale in a digital geographic world

Geographical and Environmental Modelling