Using PyWAsP for resource assessment means working with different kinds of wind climate objects. In this glossary we try to clarify the distinctions between them.
- Observed Wind Climate
A wind climate “observed” at a specific position, from a meteorogogical mast or a grid point in a weather model. Can be represented either by a multidimensional histogram (binned) or sectorwise weibull parameters (weibull).
- Generalized Wind Climate
A wind climate that has been “generalized”, using a flow model, to “remove” local effects caused by the local terrain characteristics, making it “representative” of a larger geographical area, assuming a constant surface roughness in that area. In WAsP, a generalized wind climate is most often represented as sectorwise weibull parameters for a number of generalized surface roughness classes and heights above ground.
- Predicted Wind Climate
A “Predicted” wind climate is similar to a observed wind climate, in that it represents the local wind climate at a specific location in space. In WAsP, it is used to describe wind climates that have been modelled from a generalized wind climate to a new location (from where the original wind climate was observed). A predicted wind climate is most often represented as sectorwise weibull parameters but can also be histograms.
- Binned Wind Climate
A binned wind climate refers to wind climate represented as multidimensional histogram, of “counts” or “frequency”. Binned wind climates most often takes the form of counts of occurances in 12 sector bins each representing a 30 degree wind direction bin and 30 or more wind speed bins, typically 1 m/s in width, going from 0.0 and up.
- Histogram Wind Climate
A histogram wind climate is the same as a binned wind climate.
- Weibull Wind Climate
A weibull wind climate is a wind climate where the wind speed distributions are represented by Weibull distribution parameters. Typically these are two-parameter distributions with a shape and scale parameter, typically called “k” and “A”. Most often, Weibull wind climates have 12 sectors with an “k” and “A” value per sector.
Observed, Generalized, and predicted wind climates can each be both binned or weibull-based wind climates, but, historically, observed wind climates have most often been represented as binned wind climates, while weibull fits have been used for generalized and predicted wind climates.
The subtle differences between “topograhy”, “terrain”, “orography”, and other words describing the world we try to model, can be confusing, and are often used interchangingly, and perhaps inconsistently, including by us in this user-guide. However, this is the terminology we try to adhere to:
Topography refers to the detailed description and mapping of the surface features of a particular area, including the shape and elevation of the land and the location of natural and man-made features.
Terrain refers to the physical features of a piece of land, such as hills, valleys, and bodies of water.
Orography refers to the study of mountains and mountain ranges, including their formation, structure, and distribution.
Elevation refers to the height of a point or object above a reference level, such as sea level.
- Surface roughness
Surface roughness is the variations in the surface of the earth that affect the flow of wind, including natural features such as hills, valleys, and vegetation, as well as man-made features such as buildings and structures.
- Land use
Land use refers to the way in which a particular piece of land is used, such as for agriculture, residential, commercial, or industrial purposes.
- Land cover
The land cover is the physical material that covers a piece of land, such as grass, trees, water, or pavement. This can also include human-made structures such as buildings and roads. Land cover can affect the flow of wind, and can be used to identify areas that may be more suitable for wind energy development.
- Vector map
A vector map is a type of map that uses points, lines, and polygons to represent geographical information. Vector maps are made up of discrete geographic features, such as roads, rivers, and land cover types, rather than continuous data like raster maps. Vector maps are useful for representing discrete features, such as buildings, roads, and other infrastructure, with precision and accuracy. They are also useful for storing and manipulating data in a geographic information system (GIS) and they are often used for wind resource assessment analysis.
- Raster map
Raster maps are maps that uses a grid of cells or pixels to represent geographical information. Each cell or pixel has a specific value or color that corresponds to a particular feature or attribute of the area being mapped. Raster maps are often used for displaying satellite imagery, digital elevation models, and other types of data that vary continuously across a landscape.
- WAsP Method
The process of generalizing a observed wind climate and downscaling to new locations using the WAsP flow model
- WAsP Model
A flow model utilizing a collection of fast linearized submodels to capture effects on the wind due to orograhy, surface roughness, and the atmospheric stability conditions
- WAsP Program
A Windows GUI program interfacing to the WAsP core library, including the WAsP flow model
- WAsP Bundle
A collection of WAsP related software programs, including “WAsP”, “WAsP Enegineering”, “Terrain Editor”, “Wind Analysis Tool”, and more.
- WAsP Enegineering
A WAsP Program for site assessment.
- WAsP CFD
A RANS-based method using EllipSys3D in combination with the WAsP method for improved accuracy in complex terrain
- LINCOM Model
LINCOM stands for …