TITLE: UAV - Digital elevation model from Stordalen Mire, north-western Sweden.
SITES STATION: Abisko Scientific Research Station
TIMESTAMP: 2018-07-31 15:30-17:30 (Standard time)
TIME ZONE: UTC +1 
LATITUDE: 68.35531078 
LONGITUDE: 19.0471878 
ALTITUDE: 352 m.a.s.l.
FILE RETRIVED FROM: https://data.fieldsites.se Link to metadata landing page is available in separate file in the downloaded zip.
DATA POLICY: SITES data is licensed under a Creative Commons Attribution 4.0 international license (http://creativecommons.org/licenses/by/4.0/).

PARAMETERS & UNITS: Meters (m)

DESCRIPTION: 
Near-ground digital elevation model generated from an UAV platform, with a RGB camera. Nominal pixel resolution is 5 cm. 
The ecosystem surveyed is a subartic mire located within a discontinuous permafrost zone, adjacent to lake Tornetrsk. A large portion of the mire consists of a slightly elevated drained area (palsas), altered by wetter depressions, which are not affected by the permafrost. The small-scale topography creates patches of different vegetation types. The vegetation in the dry parts consists mainly of mosses, lichens and dwarf shrubs, whereas the wet parts are dominated by sphagnum or tall graminoids.
The survey area is a polygon defined by the coordinates (GCS WGS84): 68.359498, 19.047896; 68.359334, 19.060005; 68.355284, 19.059324; 68.352760, 19.051932; 68.353023, 19.039604; 68.358099, 19.040398.  

FLIGHT PARAMETERS:
75% side and front overlap, nominally. 
Nominal flight height 100 m above ground surface.
Nominal flight speed 8 m/s.

WEATHER CONDITIONS:
Light conditions during the flight were mainly sunny.
Average wind speed during flight was 4 m/s.
 
SENSOR DESCRIPTION:
Data acquired with a Canon 9GX camera, on board of a fixed wing UAV. 

GEOREFERENCING: 
Geometric correction performed with 11 Ground Control Points (geometric model RMSE: 0.19 m)
The orthomosaic projection is SWEREF99_TM (EPSG:3006).

PROCESSING METHODS:
Orthomosaic processed using Metashape 1.6.2. 
Details about processing can be found in the Photoscan report (SITES_UAV-RGB_ANS_STM_20180731.PDF)