Copernicus Global Land Service - Land Cover 100m

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Introduction

Example: Alta Wind Energy Center, USA - Roughness Lines in windPRO from CGLS-LC100m 2015
Example: Klosterheden Plantation, Denmark - Roughness Lines in windPRO from CGLS-LC100m 2015
Example: Roughness Lines in windPRO based on CGLS-LC100m (Africa 2015 demo-dataset).

The CGLS-LC100 is a dynamic land cover map at 100m resolution and a part of the product portfolio for the Copernicus Global Land Service (CGLS) see [1]. It has the target to deliver a yearly, global land cover map which primarily will be based on PROBA-V – and later to be merged and replaced by Sentinel-2 satellite sources. Currently (2020), a dataset with near global coverage has been released with a 100m grid resolution. The map represents 2015 land cover and was derived from PROBA-V time series combined with local land cover training datasets as well as ancillary datasets.

Dataset Overview

  • Spatial Coverage: Global
  • Resolution: 100 m.
  • Data Type: Land Cover / Land Use Mapping - with roughness length mapping by EMD (lookup table)
  • Versions:
    • 2015-Global: Current version in windPRO
    • 2015-Africa-Demo: Preliminary demonstration dataset covering Africa (now discontinued in windPRO)
  • Thematic Accuracy: 80.1% +/-0.7% (see User manual, [2])
  • Updates: A yearly release is planned.

Validation

The product user manual in its version 1 from 2017 [3] holds data from the product validation from the Africa demonstration dataset. Here a comparison against other available global land cover maps is reported. Based on data from 3887 reference points, the CGLS-LS100 data come out with the best overall agreement to the ‘ground truth’ data. The overall agreement is as follows:

Table: Validation of CGLS-LS100m.
Dataset Name Overall Agreement
GlobCover 2009 50.8%
LC-CCI 2010 55.5%
MODIS 2010 63.0%
Globeland 2010 57.2%
CGLS-LC100 66.0%

Availability from within windPRO

The data are available directly from within windPRO. The data can be accessed from the online-services in the following objects:

  • Line Object (with purpose set to 'roughness lines') - this is the recommended access method
  • Area Object (with purpose set to 'roughness map based on closed lines')

Please note: Data stored in the 'Area Object' can be (fairly) easily edited by changing the legend / lookup-table definitions - as this data-type preserves the original metadata (land cover groups). This is not possible when loading roughness-lines data directly in the line object.

Usage Notes

  1. Always make a manual evaluation and adjustment of the roughness lengths obtained from this dataset; they are based on a simplified lookup table (as seen below) and you may find that any in-situ values will differ from the model values obtained from the lookup table.
  2. If you want to modify the values obtained: Load the data into a windPRO area object.
  3. We recommend loading the data directly into a line-object (due to better line-merging)
  4. For use with an area-object, please consider to reduce the size to 40kmx40km as data-downloading and processing time otherwise in the order of ~10 minutes.

Legends

The legend is based on the UN LCCS (United Nations Land Cover Classification System).
For the CGLS-LS100 main land cover product, it holds 23 discreete classes, see the table below.

Table: CGLS-LC100 with Roughness Classification Data by EMD
ID Land Cover Type EMD Roughness Length Definition UN LCSS
0 No data z0=NA NA
20 Shrubs z0=0.070 These are woody perennial plants with persistent and woody stems and without any defined main stem being less than 5 m tall. The shrub foliage can be either evergreen or deciduous.
30 Herbaceous vegetation z0=0.050 Plants without persistent stem or shoots above ground and lacking definite firm structure. Tree and shrub cover is less than 10%.
40 Cropland z0=0.100 Lands covered with temporary crops followed by harvest and a bare soil period (e.g., single and multiple cropping systems). Note that perennial woody crops will be classified as the appropriate forest or shrub land cover type.
50 Urban / built up z0=0.400 Land covered by buildings and other man-made structures.
60 Bare/sparse vegetation z0=0.020 Lands with exposed soil, sand, or rocks and never has more than 10% vegetated cover during any time of the year.
70 Snow and ice z0=0.001 Lands under snow or ice cover throughout the year.
80 Water bodies - permanent z0=0.000 Lakes, reservoirs, and rivers. Can be either fresh or salt-water bodies.
90 Wetland - herbaceous z0=0.100 Lands with a permanent mixture of water and herbaceous or woody vegetation. The vegetation can be present in either salt, brackish, or fresh water.
100 Moss and lichen z0=0.0024 Moss and lichen
111 Forest, closed, evergreen needle leaf z0=0.500 Tree canopy >70%, almost all needle leaf trees remain green all year. Canopy is never without green foliage.
112 Forest, closed, evergreen, broad leaf z0=0.500 Tree canopy >70%, almost all broadleaf trees remain green year round. Canopy is never without green foliage.
113 Forest, closed, deciduous, needle leaf z0=0.500 Tree canopy >70%, consists of seasonal needle leaf tree communities with an annual cycle of leaf-on and leaf-off periods
114 Forest, closed, deciduous, broad leaf z0=0.500 Tree canopy >70%, consists of seasonal broadleaf tree communities with an annual cycle of leaf-on and leaf-off periods
115 Closed forest, mixed z0=0.500 Closed forest, mix of types
116 Closed forest, unknown z0=0.500 Closed forest, not matching any of the other definitions
121 Forest, open, evergreen, needle leaf z0=0.400 Top layer- trees 15-70% and second layer- mixed of shrubs and grassland, almost all needle leaf trees remain green all year. Canopy is never without green foliage.
122 Forest, open, evergreen, broad leaf z0=0.400 Top layer- trees 15-70% and second layer- mixed of shrubs and grassland, almost all broadleaf trees remain green year round. Canopy is never without green foliage.
123 Forest, open, deciduous, needle leaf z0=0.400 Top layer- trees 15-70% and second layer- mixed of shrubs and grassland, consists of seasonal needle leaf tree communities with an annual cycle of leaf-on and leaf-off periods.
124 Forest, open, deciduous, broad leaf z0=0.400 Top layer- trees 15-70% and second layer- mixed of shrubs and grassland, consists of seasonal needle leaf tree communities with an annual cycle of leaf-on and leaf-off periods.
125 Open forest, mixed z0=0.400 Open forest, mix of types
126 Open forest, unknown z0=0.400 Open forest, not matching any of the other definition
200 Open Sea z0=0.000 Oceans, seas. Can be either fresh or salt-water bodies.
255 Not classified z0=NA NA

Data License and Credits

Data from the Global Land Service is subjected to the free and open access policy from the European Union’s Copernicus Regulation (see here: https://www.copernicus.eu/en/how/how-access-data). Please make sure to use a proper attribution when using these CGLS-LC100 data, such as:

Source: Contains modified Copernicus Service information [2020]. 
This product was generated by the Global Land Service of Copernicus. It is based on PROBA-V data by ESA and distributed by VITO. 
windPRO distribution and adaption by EMD International A/S.

For a complete acknowledgement and credit, the following statement can be used:

"The product was generated by the Global component of the Land Service of Copernicus, the Earth
Observation programme of the European Commission. The research leading to the current version
of the product has received funding from various European Commission Research and Technical
Development programs. The product is based on PROBA-V data provided by Belgian Science Policy
Office (BELSPO) and distributed by VITO. windPRO distribution and adaption by EMD International A/S."

Acknowledgement

  • The European Commission and the Copernicus team are acknowledged for the development and release of the free and open Copernicus data.
  • Integration of this dataset into EMD services was co-supported through the InnoWind project (www.innowind.dk) which is co-funded by the Danish Innovation Fund

References

  1. Copernicus Global Land Service, available at: https://land.copernicus.eu
  2. Copernicus Global Land Operations “Vegetation and Energy” – Product User Manual – Moderate Dynamic Land Cover 100m, Version I2.10, 2019-05-10 - (pdf)
  3. Copernicus Global Land Operations “Vegetation and Energy” – Product User Manual – Moderate Dynamic Land Cover 100m, Version I1.00, 2017-09-28 - (pdf)
  4. InnoWind project, http://www.innowind.dk