An Introduction to the AppEEARS Area Sampler

An Introduction to the AppEEARS Area Sampler. Presented by the Land Processes Distributed Active Archive Center, or LP DAAC. The Application for Extracting and Exploring Analysis Ready Samples, or AppEEARS, provides an easy and quick way to access and transform geospatial data from several federal archives. It allows for spatial, temporal, and band and layer subsetting and provides interactive visualizations for each sample output. Using the AppEEARS Area Sample, users can reproject and reformat the desired data output and associated quality data for user-defined areas of interest. Finally, Summary Statistics, calculated from the extracted data, are also made available to download with the output data files. This video provides a brief overview of how to submit an Area Sample request, visualize the output, and download the data. First, find the AppEEARS landing page using this URL. A NASA Earthdata Login account is required to use AppEEARS. Login with your NASA Earthdata account by clicking on the sign in button. Don’t worry if you do not have an account, they are freely available, and you can create an account using the 'sign in' button, as well. Let's explore the Area Sample feature. In this example, we are going to look at MODIS Land Surface Temperature, Fire, and Vegetation data for all the National Parks in Colorado from January 1, 2015 to December 31, 2017. First, click 'Extract' then 'Area Sample. There are three ways to start a sample. You can either start new request, copy a previous request, or upload a JSON file with request parameters. We are going to submit an AppEEARS area request by clicking 'Start a new request' and filling out the request form from scratch. This is the Area request form. First, we will name the request. Let's name this request Colorado NPS 2015 - 2017. When extracting by area you can either upload a GeoJSON or an ESRI shapefile, which will enable you to extract multiple areas, or you can draw a polygon to extract a single area. Let's start with uploading a shapefile zip folder of the National Parks in Colorado from data.gov. Drag and drop the zipped folder containing the .shp, .dbf, .prj, and .shx files. AppEEARS allows you to subset temporally, meaning you can select the dates or reoccurring date range that you are specifically interested in. I'm going to select January 1st, 2015 to December 31st, 2017. You can also subset the data products by adding only the data layers, or variables, you want. If you want to learn more about a layer you can click on the 'I' icon next to it. If you accidentally added a layer you can remove it by clicking on it under selected layers. Here you can select several layers from several different data products. Now I'm going to search for the rest of the data I want and add the layers I need. Next select your output options. You can choose to receive your data in GeoTIFF or NetCDF-4 file format and you have the option of either leaving your data output in their native projection or reprojecting to one of the projections listed below. When you are satisfied with the variables you've selected you can submit your request. Once your request has been successfully submitted, you will receive an email to confirm that the request has been received and a second email when the request is complete. To see your request, go to the Explore tab. This tab contains all of the requests you've submitted and includes their request details, their status, and links to visualize and download the data. Note that upon request completion, you will have 30 days to view and download your request. After 30 days your request status will change to expired and you will need to reprocess it to view and download the request again. Once you are ready to explore the data, find your request and click on the graph icon to view the contents of this request. AppEEARS allows you the preview and interact with your data values. These graphs are aggregated statistics for your region of interest through time. For Area samples, AppEEARS provides two plot types. A box-and-whisker for variables that contain continuous data values, and stacked bar charts for categorical data values. The box and whisker plot illustrates the central tendency and distribution of the data values extracted for each input feature or area of interest through time. It also allows you to preview the associated quality information as stacked bar charts. These display the pixel counts for each quality category. Once you are done exploring the data, you can download the output files via the dropdown arrow or by returning to the explore tab. In addition to the data extracted for your requests, AppEEARS offers a number of supporting or auxiliary files including: ISO 19115 compliant metadata, a granule list with links to the source data files, a readme for additional request details, a JSON file to share and reproduce requests, and product specific quality lookup tables and aggregated statistics. Finally, the GeoTIFF or netCDF-4 files containing the extracted data values are available to download individually or as a bulk download. So, there you have it, AppEEARS, an intuitive, time-saving application that provides access to geospatial data from a variety of federal data archives all in one place! If at any time you need help while using AppEEARS feel free to click Help. This will provide you with information on how to use AppEEARS and on what data products are available in AppEEARS. You can also always contact the LP DAAC User Services team at lpdaac@usgs.gov. Thank you for watching this video on the AppEEARS Area Sampler presented by the Land Processes Distributed Active Archive Center or LP DAAC.