Objective: The purpose of this module is to introduce you to the many types of collections of images available in Google Earth Engine. These include sets of individual satellite images, pre-made composites (which merge multiple individual satellite images into one composite image), classified land use and land cover (LULC) maps, weather data, and other types of datasets.
Learning Outcomes
- Accessing and viewing sets of images in Earth Engine.
- Extracting single scenes from collections of images.
- Applying visualization parameters in Earth Engine to visualize an image.
Through the class, you have already been introduced to imagery, one of the core building blocks of remotely sensed imagery in Earth Engine. In this module, we will expand on this concept of images by introducing ImageCollection . Image collections in Earth Engine organize many different images into one larger data storage structure. Image collections include information about the location, date collected, and other properties of each image, allowing you to sift through the ImageCollection for the exact image characteristics needed for your analysis. GEE image collections are available from a wide range of sources, including Landsat, Sentinel-2, MODIS, NASA Global Imagery Browse Services (GIBS), and DigitalGlobe. In addition to the pre-defined image collections, users can also create custom image collections by combining multiple image collections into a single collection. This can be useful for monitoring land cover or land use in a specific region.
In simplest terms, An ImageCollection is a stack or sequence of images. An ImageCollection can be loaded by pasting an Earth Engine asset ID into the ImageCollection constructor. You can find ImageCollection IDs in the data catalog.