Comparing Global Population Trends with GeoBoundaries and Landscan¶

Introduction¶

This tutorial demonstrates how to use GeoBoundaries and the Landscan Population Dataset to compare population data for different Admin1 regions using Earth Engine. You will learn how to load admin boundaries, filter a population dataset by date range, extract resolution information, and create a time-series chart comparing population data.

To view the complete code for this tutorial, click here.

Section 1: Load Admin Boundaries (GeoBoundaries) and Select Regions¶

Use the ee.FeatureCollection method to load the admin boundaries dataset from GeoBoundaries.

var admin0 = ee.FeatureCollection("projects/sat-io/open-datasets/geoboundaries/CGAZ_ADM0");

Select two Admin1 regions to compare: Japan and Mexico.

var region1 = 'Japan';
var region2 = 'Mexico';

Use the filter method to select the desired regions from the admin boundaries dataset.

var selectedRegions = admin0.filter(ee.Filter.inList('shapeName', [region1, region2]));
print('Filtered Admin1 collection', selectedRegions);

Section 2: Load Landscan Population Dataset¶

Use the ee.ImageCollection method to load the Landscan population dataset.

var landscan = ee.ImageCollection("projects/sat-io/open-datasets/ORNL/LANDSCAN_GLOBAL");
var band = 'b1';

Set the date range for the population data using ee.Date.fromYMD.

var startYear = 2000;
var endYear = 2020;

var startDate = ee.Date.fromYMD(startYear, 1, 1);
var endDate = ee.Date.fromYMD(endYear + 1, 1, 1);

Use the filter method to filter the population dataset by date range.

var populationFiltered = landscan.filter(ee.Filter.date(startDate, endDate)).select(band);
print('Filtered Population Collection', populationFiltered);

Section 3: Extract Resolution of Landscan Dataset¶

Get the resolution of the population dataset using projection.nominalScale.

var projection = populationFiltered.first().projection();
var resolution = projection.nominalScale();
print('Landscan Global Resolution', resolution);

Section 4: Create Time-Series Chart Comparing Population¶

Create a time-series chart comparing the population data for the selected regions.

var chartOptions = {
    title: 'Population Time Series',
    vAxis: {
        title: 'Population',
      },
      hAxis: {
        title: '',
        format: 'YYYY',
        gridlines: {color: 'transparent'}

      },
  }

var chart = ui.Chart.image.seriesByRegion({
  imageCollection: populationFiltered,
  regions: selectedRegions,
  reducer: ee.Reducer.sum(),
  scale: resolution,
  seriesProperty: 'shapeName'
}).setChartType('ColumnChart')
  .setOptions(chartOptions);
print(chart);

Keywords: GeoBoundaries, Landscan Population Dataset, Earth Engine, Admin1 regions, Population data

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