Near-Global Forest Canopy Heights GLAD: Difference between revisions

From Wiki-WindPRO
Jump to navigation Jump to search
Line 15: Line 15:


=== Usage Notes ===
=== Usage Notes ===
# Point 1
# Canopy heights above 30m height is underestimated as the model used saturated above 30 m: The height og the tallest trees are not adequately represented
# Point 2
# Map is still condisidered as a protopype - altorithms and data are being improved.
# GEDI data overestimate forest height on slopes within temperate and subtropical mountain grasslands
# Tree height over cities and suburbs may be confounded with building height
# Geolocation precision and land surface height estimation may be responsible for some map errors


== Availability from within WindPRO ==
== Availability from within WindPRO ==

Revision as of 13:19, 8 September 2020

GlobalGLAD Forest Map – Site Near Ouésso, Republic of the Congo.

Introduction

The Near Global Forest Canopy Height (GLAD, 2019) is a dataset developed from a fusion of GEDI lidar data (Global Ecosystem Dynamics Investigation Lidar) and Landsat imagery data.

This dataset has a near global spatial coverage ranging from latitudes 52.6S to 52.6N.

Currently (2020) it is to be considered as a prototype map as both machine learning algorithms and available data are still being being improved.

The dataset was developed by the Global Land Analysis and Discovery (GLAD) laboratory in the Department of Geographical Sciences at the University of Maryland.

The data reflects the 95% relative height of the canopy. In the current version, tree heights beyond 30m are saturated by the model used.

Usage Notes

  1. Canopy heights above 30m height is underestimated as the model used saturated above 30 m: The height og the tallest trees are not adequately represented
  2. Map is still condisidered as a protopype - altorithms and data are being improved.
  3. GEDI data overestimate forest height on slopes within temperate and subtropical mountain grasslands
  4. Tree height over cities and suburbs may be confounded with building height
  5. Geolocation precision and land surface height estimation may be responsible for some map errors

Availability from within WindPRO

The forest height data is available directly from within windPRO in 30 meter resolution. The data can be accessed from the online-services in the 'Elevation Grid Object' in the following way.

  1. Open the 'Elevation Grid Object'.
  2. Select ‘Data type’ to ‘Heights above terrain (a.g.l) for “elements”.
  3. Click ‘Add Layer from Online Data‘.

Data Type and Use in windPRO

Coverage

This dataset nearly covers the world, ranging from latitudes 52.6S to 52.6N


License and Acknowledgement

The map is in the public domain. The Global Land Analysis and Discovery laboratory in the Department of Geographical Sciences at the University of Maryland has made the data available free of charge.

We recommend using the following attribution when using the data:

Source:

Global forest height data from the Global Land Analysis and Discovery laboratory in the Department of Geographical Sciences at the University of Maryland. Processing and distribution through EMD and windPRO. Public Domain.

References:

P. Potapov, X. Li, A. Hernandez-Serna, A. Tyukavina, M.C. Hansen, A. Kommareddy, A. Pickens, S. Turubanova, H. Tang, C. E. Silva, J. Armston, R. Dubayah, J. B. Blair, M. Hofton (2020): Global Forest Canopy Height (2019), https://glad.earthengine.app/view/global-forest-canopy-height-2019

External Links

  1. https://glad.umd.edu/dataset/gedi/
  2. https://glad.earthengine.app/view/global-forest-canopy-height-2019
  3. https://gedi.umd.edu/instrument/instrument-overview/
  4. https://svs.gsfc.nasa.gov/13090