// Load the terrain data
var terrain = ee.Image('USGS/SRTMGL1_003');

// Select an area of interest
var aoi = ee.Geometry.Rectangle([lon1, lat1, lon2, lat2]);

// Clip the terrain data to the area of interest
var clippedTerrain = terrain.clip(aoi);

// Define the visualization parameters for the elevation data
var visParams = {
  min: 0,
  max: 4000,
  palette: ['blue', 'green', 'yellow', 'red']
};

// Display the clipped elevation data on the map
Map.addLayer(clippedTerrain, visParams, 'Elevation');

// Export the clipped terrain data as a GeoTIFF image
Export.image.toDrive({
  image: clippedTerrain,
  description: 'elevation_data',
  scale: 30,
  region: aoi
});