Format the region reduction into a table (server-side Earth Engine).Reduce the data region by a statistic (server-side Earth Engine).Filter the dataset (server-side Earth Engine).Preparation of every dataset for visualization follows the same basic steps: The vegetation grades from mostly ponderosa pine and Douglas-fir at low elevations on the western side, to pines and Sierra juniper on the eastern side, and to fir and other conifers at higher elevations. The region of interest for these examples is the Sierra Nevada ecoregion of California. To analyze even larger datasets, you may need to modify the workflow to export FeatureCollection results from Earth Engine as static assets and then use the static assets to perform the subsequent steps involving Earth Engine table formatting, conversion to pandas DataFrame, and charting with Altair. Note: This notebook demonstrates an analysis template and interactive workflow that is appropriate for a certain size of dataset, but there are limitations to interactive computation time and server-to-client data transfer size imposed by Colab and Earth Engine.
Earth Engine is used to access, clean, and reduce large amounts of spatiotemporal data, pandas is used to analyze and organize the results, and Altair is used to visualize the results.
It combines a series of technologies, each best suited to a particular task in the data reduction process. ContextĪt the heart of this tutorial is the notion of data reduction and the need to transform data into insights to help inform our understanding of Earth processes and human's role in them. Note that this tutorial uses the Earth Engine Python API in a Colab notebook. Data representation with various Altair chart types.Converting an Earth Engine table to a pandas DataFrame.Transferring an Earth Engine table to a Colab Python kernel.Time series region reduction in Earth Engine.This tutorial provides methods for generating time series data in Earth Engine and visualizing it with the Altair library using drought and vegetation response as an example.