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How are projections determined in Google Earth Engine?
Projections (left side of flow chart) of each operation are determined from the output. Curved lines indicate the flow of information to the reprojection: specifically, the output projection and scale. In Earth Engine, projections are specified by a Coordinate Reference System (CRS or the crs parameter of many methods).
How does a Coordinate Reference System ( CRS ) work?
A coordinate reference system (CRS) then defines, with the help of coordinates, how the two-dimensional, projected map in your GIS is related to real places on the earth.
Which is map projection and coordinate reference system to use?
The decision as to which map projection and coordinate reference system to use, depends on the regional extent of the area you want to work in, on the analysis you want to do and often on the availability of data. A traditional method of representing the earth’s shape is the use of globes.
Where to find on the fly projection in QGIS?
This is because QGIS has a feature called On-the-fly CRS transformation. The projection text at the bottom-right of QGIS now has the words OTF next the EPSG:4326`. To learn more, let’s explore the CRS option in QGIS. Go to Settings ‣ Options….
Why is my projection invalid in Earth Engine?
If you try to use an image like this in a computation, you may see an error like: The default WGS84 projection is invalid for aggregations. Specify a scale or crs & crs_transform. Generally, an aggregation at 1-degree scale is not desired or intended, so Earth Engine gives this friendly reminder to provide a complete specification for the output.
Why is feature collection not possible in Google Earth Engine?
No data was found in classifier training input. Why is this possible for images but not for feature collections on Google Earth Engine? Here is how I tried reducing it to an image, which also did not work so far:
What is the native resolution of Google Earth?
The native resolution is the nominal pixel scale in meters of the lowest level of the image pyramid. Because each band of an image can have a different scale and/or projection, if you call projection () on an image with at least one band that doesn’t have the same projection as the others, you may see an error like: