MODIS VCF: Difference between revisions
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The Modis VCF (Vegetation Continuous Fields) data holds a global 500 x 500 m resolution dataset on the vegetation cover. The dataset consists of three files: Percent trees, bare ground and herbaceous vegetation. The WindPRO online data service converts these three files into a roughness classification legend. The Modis VCF is an annual representation of the period November 2000 to November 2001. | The Modis VCF (Vegetation Continuous Fields) data holds a global 500 x 500 m resolution dataset on the vegetation cover. The dataset consists of three files: Percent trees, bare ground and herbaceous vegetation. The WindPRO online data service converts these three files into a roughness classification legend. The Modis VCF is an annual representation of the period November 2000 to November 2001. | ||
== Coverage == | == Coverage == | ||
The coverage is near global. Only Antarctica and the polar region above 80 degrees north is missing. Please note that this roughness classification is based on a vegetation index only. | The coverage is near global. Only Antarctica and the polar region above 80 degrees north is missing. Please note that this roughness classification is based on a vegetation index only. Hence, urban areas must be added manually. In addition, the conversion from vegetation cover to roughness classification is still experimental only. | ||
== EMD Processing == | == EMD Processing == | ||
An overview is of the EMD legend is shown in the table below. This legend is created by using a simple algorithm for the conversion from canopy cover to roughness class. For now, this algorithm is a simple linear relationship – a function of the canopy cover only. At a later stage, this algorithm may be improved by adding dependencies on herbaceous vegetation and bare ground percentages. | An overview is of the EMD legend is shown in the table below. This legend is created by using a simple algorithm for the conversion from canopy cover to roughness class. For now, this algorithm is a simple linear relationship – a function of the canopy cover only. At a later stage, this algorithm may be improved by adding dependencies on herbaceous vegetation and bare ground percentages. | ||
Revision as of 22:05, 23 May 2013
Introduction
The Modis VCF (Vegetation Continuous Fields) data holds a global 500 x 500 m resolution dataset on the vegetation cover. The dataset consists of three files: Percent trees, bare ground and herbaceous vegetation. The WindPRO online data service converts these three files into a roughness classification legend. The Modis VCF is an annual representation of the period November 2000 to November 2001.
Coverage
The coverage is near global. Only Antarctica and the polar region above 80 degrees north is missing. Please note that this roughness classification is based on a vegetation index only. Hence, urban areas must be added manually. In addition, the conversion from vegetation cover to roughness classification is still experimental only.
EMD Processing
An overview is of the EMD legend is shown in the table below. This legend is created by using a simple algorithm for the conversion from canopy cover to roughness class. For now, this algorithm is a simple linear relationship – a function of the canopy cover only. At a later stage, this algorithm may be improved by adding dependencies on herbaceous vegetation and bare ground percentages.
Acknowledgement
Raw data source for this dataset was the Global Land Cover Facility at http://www.landcover.org