![]() Accurate geographic location of data is maintained. hard copy maps, is in vector form no data conversion is required. Graphic output is usually more aesthetically pleasing (traditional cartographic representation) since most data, e.g. The features of the real world are depicted in vector data layers as points, lines, and polygons, and in the raster database as cells or zones of cells.Īdvantages:Data can be represented at its original resolution and form without generalization. Being able to move back and forth smoothly between raster and vector representations of data is an important feature of spatial hydrology.Ī well-constructed geospatial database for hydrology incorporates both vector and raster data in a tightly connected raster-vector data model, as illustrated in the graphic below. Moreover, precipitation, evaporation, and other climatic variables are defined continuously through space and measured at particular points where there are climate stations. However, the watershed areas draining to those points are best derived from Digital Elevation Models (DEM), which are raster representations of land surface terrain elevation considered as a continuous surface. Rivers are best represented as lines, and gaging stations and other control points on rivers like water right locations are best represented as points. Therefore, the connection between raster and vector data is critical in spatial hydrology, perhaps more so than in other applications of GIS. However, most spatial data sources are in vector data format, which also provides unique visualization and geographic analysis benefits. Those functions are usually offered by raster data models. Spatial hydrology involves both spatial data development and hydrologic modeling, both of which require intensive computational functions. Continuous surfaces can be represented using the grid or raster data Model in which a mesh of square cells is laid over the landscape and the value of the variable defined for each cell. INTRODUCTION:Continuous surfaces can be represented using the grid or raster data Model in which a mesh of square cells is laid over the landscape and the value of the variable defined for each cell.
0 Comments
Leave a Reply. |