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I am a beginner in GEE.

The area of interest is already imported and visualized on the map.

Is it possible for the precipitation, to create a histogram or another diagram out of the available weather data, for the selected area and time frame?

The level of precipitation has to be compared with another time steps, therefore, I need to have a table with the amount of precipitation.

Is it possible to visualize precipitation at the map and creating a layer of precipitation?

An example of my code:

var imageCollection = ee.ImageCollection("OREGONSTATE/PRISM/AN81m");
//Import Fusion Table - for study area    
var study_area = ee.FeatureCollection('ft:1QDQ2uqIShT65d4uKcq1DJpjVne_jgnBRgDzN-RaY');

//Add study_area to the map    
 Map.addLayer(study_area, {color:'green'}, 'study_area');

//To center the map at the study_area    
Map.centerObject(study_area, 6 );

//To spatially filter the weather data for the study_area    
 var spatialFiltered = imageCollection.filterBounds(study_area);   
print('spatialFiltered', spatialFiltered);

//To temporarily filter the weather data for the study_area    
var temporalFiltered = spatialFiltered.filterDate('1899-01-01', '1904-12-31');    
print('temporalFiltered', temporalFiltered);

Here is the link with the weather data:

https://explorer.earthengine.google.com/#detail/OREGONSTATE%2FPRISM%2FAN81m

closed as too broad by PolyGeo Mar 1 at 21:10

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  • You will need to change the permissions on the fusion table to make it public. – svangordon Sep 10 '18 at 16:04
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You can create charts in Earth Engine using the ui.Chart methods. You can change the chart type by using different chart methods or setting the chart type with .setChartType. You can turn the collection of PRISM images into a single image for visualization using the .reduce method. Here's code that does both using an arbitrary geometry as the study area:

// Import Fusion Table - for study area    
// var study_area = ee.FeatureCollection('ft:1QDQ2uqIShT65d4uKcq1DJpjVne_jgnBRgDzN-RaY');

var study_area = /* color: #d63000 */ee.Geometry.Polygon(
        [[[-123.83038412388669, 38.476017204621904],
          [-123.03936836339949, 36.38243915984227],
          [-121.45733686974188, 36.6649580095569],
          [-122.16046197392444, 38.33827226006227]]]);

var imageCollection = ee.ImageCollection("OREGONSTATE/PRISM/AN81m");

//Add study_area to the map    
 Map.addLayer(study_area, {color:'green'}, 'study_area');

//To center the map at the study_area    
Map.centerObject(study_area, 6 );

// Spatially filtering the images has no effect
// //To spatially filter the weather data for the study_area    
// var spatialFiltered = imageCollection.filterBounds(study_area);   
// print('spatialFiltered', spatialFiltered);

//To temporarily filter the weather data for the study_area    
var temporalFiltered = imageCollection.filterDate('1899-01-01', '1904-12-31')
  .select('ppt');    
print('temporalFiltered', temporalFiltered);


// Create a chart with time series percipitation
var chart = ui.Chart.image.series(temporalFiltered, study_area)
print(chart)

// Create an image representing mean percipitation
var meanPercipitation = temporalFiltered.reduce(ee.Reducer.mean())
Map.addLayer(meanPercipitation, {min:0, max: 200}, 'percipitation')

https://code.earthengine.google.com/8729727fbbc991c4b5c718351ae6c2bb

It's worth noting that filtering an image collection like PRISM, where each image covers the entire spatial domain, will have no effect.

  • Thank you!! I decided to use another dataset ('var imageCollection = ee.ImageCollection("UCSB-CHG/CHIRPS/DAILY");') for my area of investigation because it is located in Africa. I still have an issue creating an image representing the mean precipitation. A new layer is been added and created but the image is just black. Is there a way to have somehow the data from the chart into table? – gispaew Sep 11 '18 at 15:11
  • @gispaew I'm also using CHIRPS in Africa. Your image is all black because you're not setting the visualization parameters. You can use the inspector to find a reasonable max parameter for Map.addLayer. – svangordon Sep 12 '18 at 2:11

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