Copernicus Global Land Service - Land Cover 100m

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