Amazon_Rainforest_Deforestation

// Load the Amazon region geometry
var amazonRegionGeometry = ee.FeatureCollection("projects/ee-sanjeevanilakade25/assets/amazon_basin").geometry().dissolve({'maxError': 1});
print('Amazon Region Geometry:', amazonRegionGeometry);

// Add the Amazon region geometry to the map for visualization
Map.addLayer(amazonRegionGeometry, {color: 'blue' }, 'Amazon Rainforest Geometry', true, 0.5);

// Load the Hansen Global Forest Change dataset
var forestChangeImage = ee.Image("UMD/hansen/global_forest_change_2022_v1_10").select(['lossyear']).clip(amazonRegionGeometry);
print('Forest Change Image:', forestChangeImage);

// Center the map on the region of interest
Map.centerObject(amazonRegionGeometry, 4);

// Display the forest loss image on the map
Map.addLayer(forestChangeImage, {bands: ['lossyear'], palette: ['FF0000']}, 'Forest Loss');

// Define the years of interest
var yearsOfInterest = ee.List.sequence(0, 22);

// Map over the years and calculate deforestation area
var deforestationAreas = yearsOfInterest.map(function(year) {
  var lossYearMask = forestChangeImage.eq(ee.Number(year)).selfMask();
  var pixelAreaImage = lossYearMask.multiply(ee.Image.pixelArea());
  var areaStats = pixelAreaImage.reduceRegion({
    reducer: ee.Reducer.sum(),
    geometry: amazonRegionGeometry,
    scale: 200,
    maxPixels: 1e14
  });

  // Convert the image value to a Number
  var lossArea = ee.Number(areaStats.get('lossyear'));

  // Multiply pixel area by loss area (assuming 'lossyear' represents loss area)
  var deforestationArea = lossArea.multiply(0.0001);

  return lossYearMask.set('area', deforestationArea)
    .set('year', ee.String(ee.Number(year).add(2000).toInt()));
});

// Create an ImageCollection from the mapped result
var deforestationImageCollection = ee.ImageCollection.fromImages(deforestationAreas);
print('Deforestation Image Collection:', deforestationImageCollection);

// Aggregate the results for charting
var yearsList = deforestationImageCollection.aggregate_array('year');
var deforestationAreasList = deforestationImageCollection.aggregate_array('area');
var deforestationData = ee.Dictionary.fromLists(yearsList, deforestationAreasList);
print('Deforestation Data:', deforestationData);

// Create an area chart for deforestation
var deforestationChart = ui.Chart.array.values({
  array: deforestationData.values(),
  axis: 0,
  xLabels: deforestationData.keys()
}).setChartType('AreaChart').setOptions({
  title: 'Deforestation Over the Years',
  hAxis: {title: 'Year'},
  vAxis: {title: 'Deforestation Area (in hectares)'}
});

// Print the deforestation chart
print('Deforestation Chart:', deforestationChart);

// Function to calculate cumulative sum with modified logic
var cumulativeSum = function(element, accumulator) {
  accumulator = ee.List(accumulator);
  return accumulator.add(ee.Number(element).add(accumulator.get(-1)));
};

// Apply cumulative sum function to the list
var cumulativeDeforestationList = deforestationAreasList.iterate(cumulativeSum, ee.List([0]));
print('Cumulative Deforestation List:', cumulativeDeforestationList);

// Convert the cumulative list to a dictionary with years as keys
var cumulativeDeforestationDict = ee.Dictionary.fromLists(yearsList, ee.List(cumulativeDeforestationList).slice(1));
print('Cumulative Deforestation Dictionary:', cumulativeDeforestationDict);

// Create an area chart for cumulative deforestation
var cumulativeDeforestationChart = ui.Chart.array.values({
  array: cumulativeDeforestationDict.values(),
  axis: 0,
  xLabels: cumulativeDeforestationDict.keys()
}).setChartType('AreaChart').setOptions({
  title: 'Cumulative Deforestation Over the Years',
  hAxis: {title: 'Year'},
  vAxis: {title: 'Cumulative Deforestation Area  (in hectares)'}
});

// Print the cumulative deforestation chart
print('Cumulative Deforestation Chart:', cumulativeDeforestationChart);

// Function to calculate deforestation rate
var calculateDeforestationRate = function(value, accumulator) {
  accumulator = ee.List(accumulator);
  var index = accumulator.size();
  
  // Calculate deforestation rate
  var deforestationRate = ee.Number(value).divide(index);
  
  return accumulator.add(deforestationRate);
};

// Apply the function to cumulativeDeforestationList using iterate
var deforestationRateList = ee.List(ee.List(cumulativeDeforestationList).iterate(calculateDeforestationRate, ee.List([])));

// Print the result
print('Deforestation Rate List:', deforestationRateList);

var deforestationRateDict = ee.Dictionary.fromLists(yearsList, deforestationRateList.slice(1));
print('Cumulative Deforestation Dictionary:', deforestationRateDict);

// Create an area chart for cumulative deforestation
var deforestationRateChart = ui.Chart.array.values({
  array: deforestationRateDict.values(),
  axis: 0,
  xLabels: deforestationRateDict.keys()
}).setChartType('AreaChart').setOptions({
  title: 'Deforestation Rate Chart',
  hAxis: { title: 'Year' },
  vAxis: { title: 'Deforestation Rate (in hectares / year)' },
  pointSize: 5,  
  lineWidth: 2,  
  series: {  
    0: { pointShape: 'circle' }  
  }
});

// Display the chart
print(deforestationRateChart);