Obtain monthly and yearly average values of EVI using MODIS data on Google Earth Engine

Here’s a more human-sounding version of the blog post:

Google Earth Engine: Your Go-To for EVI Analysis with MODIS Data

Ever wonder how scientists keep tabs on the health of our planet’s vegetation? Well, the Enhanced Vegetation Index (EVI) is one of their secret weapons. Think of it as a vital sign for plants, giving us clues about everything from ecosystem shifts to how well crops are growing, and even the effects of climate change. And guess what? Google Earth Engine (GEE) makes crunching this data easier than ever!

EVI is pretty smart. Unlike some other indices, it cuts through the noise – literally. It uses red, near-infrared, and blue light to correct for atmospheric fuzz and background clutter, giving you a much clearer picture of how green things really are.

Now, let’s talk about MODIS. These instruments are like the eyes in the sky, riding on NASA’s Terra and Aqua satellites. They constantly scan the Earth, gathering data in a whopping 36 different bands! The MOD13Q1 product is particularly useful, giving us EVI data every 16 days at a pretty fine resolution (250 meters). Perfect for tracking vegetation changes!

Okay, ready to get your hands dirty? First, you’ll need a Google Earth Engine account and a little familiarity with the JavaScript API. Fire up the GEE code editor in your browser, and let’s get started.

First things first: accessing the MODIS data. Think of GEE as a giant library – you just need to know how to ask for the right book. Use the ee.ImageCollection function to grab the MOD13Q1 EVI dataset. Next, narrow things down. Tell GEE what area you’re interested in and what time period you want to analyze.

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