Let us get started.

Adds a band containing image date as years since 2000.
function createTimeBand(img) {
var year = ee.Date(img.get('system:time_start')).get('year').subtract(2000);
return ee.Image(year).byte().addBands(img);
}
var collection = ee.ImageCollection("MODIS/006/MOD13A2")
.select('EVI')
.map(createTimeBand);
var linearFit = collection.select(['year', 'EVI'])
.reduce(ee.Reducer.linearFit());
// Compute a linear fit over the series of values at each pixel, visualizing
// the y-intercept in green, and positive/negative slopes as red/blue.
Map.addLayer(
collection.reduce(ee.Reducer.linearFit()),
{min: 0, max: [50.0, 1500, -50.0], bands: ['scale', 'offset', 'scale']},
'EVI trend');
Map.addLayer(collection.reduce(ee.Reducer.linearFit()), imageVisParam, 'EVI SLope')

Play around with the Layers.

In this sort course, i will show you how to filter an image collection with google earth engine. This includes setting up the date and time of your AOI(Area of interest).

Lets begin.

// Imports
var L8 = ee.ImageCollection("LANDSAT/LC08/C01/T1_TOA"),
region =
/* color: #98ff00 */
/* shown: false */
/* displayProperties: [
{
"type": "rectangle"
}
] */
ee.Geometry.Polygon(
[[[35.91227604954444, 32.064377236024306],
[35.91227604954444, 30.657243564613967],
[38.16447331516944, 30.657243564613967],
[38.16447331516944, 32.064377236024306]]], null, false),
imageVisParam = {"opacity":1,"bands":["B5","B2","B3"],"min":-0.11627322919749453,"max":0.5422723495038532,"gamma":1};
//print(L8.size());var filtered_region = L8.filterBounds(region);
print(filtered_region.size());
Map.addLayer(filtered_region)
var filtered_region_date = filtered_region.filterDate('2020-01-01', '2020-07-01');
print(filtered_region_date.size());
var region_fin = L8.filterBounds(region)
.filterDate('2020-01-01', '2020-07-01');
print(region_fin.size());
var Median_Image = region_fin.median();
Map.addLayer(Median_Image, imageVisParam, 'Study_Area');

This should be the outcome.

Revisiting The Tigray War Using Geospatial Technology.

It is sad that i have to revisit this topic again, if you are aware, i wrote about it a month ago hoping things would have improved in the near future. Unfortunately, things have gone from bad to worse, with signs of imminent…

According to Crunchbase, Geo AI startup’s are getting alot of attention from Venture Capitalist,these innovative company’s raised around 200 million usd in 2019 from venture backers, up from 80 million in 2016. This figure is projected to hit 400 million in 2023.

Here are some startup’s to watch plus how…

On 19 September 2021, the Cumbre Vieja went up in flames as it erupted, resulting to lava and a cloud of ash spreading around the island of La Palma. The eruption led to the evacuation of more than 5,000 people, and the lava flow has destroyed more than 450 buildings so far.
Satellite imagery can help you understand the effects of this volcanic eruption, flow of the lava, damaged caused and to what extent.
SOME SATELLITE IMAGERY
Lets look at some satellite imagery.

Stephen Chege-Tierra Insights

Providing Geospatial data related content for Humanitarian, Defense, Development and Agriculture organisations. For more visit https://tierrainsights.com/blog/

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