PRISM

JavaScript code to download PRISM data

// First, import ImageCollection ID: “OREGONSTATE/PRISM/AN81d”, PRISM Daily Spatial Climate Dataset AN81d

// Load a Fusion Table from the ID using the FeatureCollection constructor.

var ballpark = ee.FeatureCollection(“ft:1EXApOoxEgJUFlbMjUodfxBSWlRvgQNpABeddHqiN”);

var usa = ee.FeatureCollection(“ft:1ksBc_-cWnek37HFTMr0FXfBtOETBeYYbB1YeSg”);

// Load PRISM input imagery.
var tmax = ee.ImageCollection(PRISM)
.filterDate(‘2015-04-01’, ‘2018-10-31’)
.select(‘tmax’);

var tmin = ee.ImageCollection(PRISM)
.filterDate(‘2015-04-01’, ‘2018-10-31’)
.select(‘tmin’);

var tdmean = ee.ImageCollection(PRISM)
.filterDate(‘2015-04-01’, ‘2018-10-31’)
.select(‘tdmean’);

/////////////////////////////////////////////////////////

//Create a collection of triplets, {imageID, ballpark, first}:

var triplets = tdmean.map(function(image) {
return image.select(‘tdmean’).reduceRegions({
collection: ballpark.select([‘Team Name’]),
reducer: ee.Reducer.first(),
scale: 1000
}).filter(ee.Filter.neq(‘first’, null))
.map(function(f) {
return f.set(‘imageId’, image.id());
});
}).flatten();

print(triplets.first()); //properties: ballpark, imageId, first

//////////////////////////////////////////////////////////////////////////

// Format a table of triplets into a 2D table of rowId x colId.
var format = function(table, rowId, colId) {
// Get a FeatureCollection with unique row IDs.
var rows = table.distinct(rowId);
// Join the table to the unique IDs to get a collection in which
// each feature stores a list of all features having a common row ID.
var joined = ee.Join.saveAll(‘matches’).apply({
primary: rows,
secondary: table,
condition: ee.Filter.equals({
leftField: rowId,
rightField: rowId
})
});

return joined.map(function(row) {
// Get the list of all features with a unique row ID.
var values = ee.List(row.get(‘matches’))
// Map a function over the list of rows to return a list of
// column ID and value.
.map(function(feature) {
feature = ee.Feature(feature);
return [feature.get(colId), feature.get(‘first’)];
});
// Return the row with its ID property and properties for
// all matching columns IDs storing the output of the reducer.
// The Dictionary constructor is using a list of key, value pairs.
return row.select([rowId]).set(ee.Dictionary(values.flatten()));
});
};

var table1 = format(triplets, ‘Team Name’, ‘imageId’);
var desc2 = ‘tdmean’;

Export.table.toDrive({
collection: table1,
description: desc2,
fileNamePrefix: desc2,
fileFormat: ‘CSV’
});

Map code

var prism = ee.ImageCollection(‘OREGONSTATE/PRISM/AN81d’)
.filter(ee.Filter.date(‘2018-07-05’, ‘2018-07-06’));
var tmaxMap = prism.select(‘tmax’);
var tmaxVis = {
min: 20.0,
max: 45.0,
palette: [‘yellow’, ‘orange’, ‘red’],
};
Map.setCenter(-100.55, 40.71, 4);
Map.addLayer(tmaxMap, tmaxVis, ‘tmax’);