Abstract:
The Zonal Mean over a given area is the sequence of data generated by taking the average over a range of longitudes for each latitude.
Input parameters: * data parameter values - examples are atmospheric chemical species concentrations from a given pressure layer;
* user-selected geographic coordinates;
* user-selected temporal range (
Begin and
End values).
... Output Description:
* PNG image of Zonal Mean values for the user-selected area
* Corresponding HDF data file array with Zonal Mean values
Output Parameters:
Same as input
File Type:
Input: HDF4 Output: HDF4, PNG image
Sub-definitions:
- Grid: a two-dimensional data structure
- Latitude: vertical dimension of grid
- Longitude: horizontal dimension of grid
- Pixel: grid element containing data value
- Subset: a section of the grid reduced in the vertical or
horizontal dimension, or both
Service Description:
The Zonal Mean calculation only works with data in a single atmospheric layer (defined by pressure in hPA), such as 300 hPA as an example. The zonal mean cannot be calculated for a pressure range, i.e., for the range 300-400 hPA.
The zonal mean operation works by exporting the data from the dataset and then averaging along the longitude axis for each latitude point. The extent of the range of longitudes averaged, and the latitudes considered, is limited by the edges of the bounding box selected by the user.
Origin/Software:
Utilizes PyGrADS