MODIS — Daily Satellite Observations¶
Provider
NASA (Terra and Aqua satellites)
Website
GEE | lpdaac.usgs.gov
Access Level
🔵 GEE (best) | 🟡 USGS Earth Data
Resolution
250m, 500m, or 1km depending on product
Revisit Time
Daily (Terra at 10:30am, Aqua at 1:30pm)
Archive
February 2000 to present
Key MODIS Products for India¶
| Product ID | Name | Resolution | Frequency | Use |
|---|---|---|---|---|
MOD13Q1 |
NDVI/EVI | 250m | 16-day | Crop monitoring, phenology |
MOD11A1 |
Land Surface Temperature | 1km | Daily | Heat islands, drought |
MCD64A1 |
Burned Area | 500m | Monthly | Forest fire tracking |
MOD09GA |
Daily Surface Reflectance | 500m | Daily | True colour, indices |
MOD14A1 |
Active Fire/Thermal Anomalies | 1km | Daily | Fire alerts |
MOD16A2 |
Evapotranspiration | 500m | 8-day | Water stress, irrigation |
MOD44W |
Water Mask | 250m | Annual | Permanent water bodies |
MODIS in GEE: Crop Season Detection¶
// GEE: MODIS NDVI Seasonal Profile for Punjab (Double Cropping)
var punjab = ee.Geometry.Rectangle([73.5, 29.5, 77.0, 32.5]);
// Load MOD13Q1 (16-day NDVI) for 2023
var modis = ee.ImageCollection("MODIS/061/MOD13Q1")
.filterBounds(punjab)
.filterDate('2023-01-01', '2023-12-31')
.select('NDVI');
// Scale NDVI (MODIS NDVI is stored *10000)
var scaleNDVI = function(img) {
return img.multiply(0.0001).copyProperties(img, ['system:time_start']);
};
modis = modis.map(scaleNDVI);
// Chart: NDVI over time (shows two crop peaks = wheat + rice)
var chart = ui.Chart.image.series(modis, punjab, ee.Reducer.mean(), 500)
.setOptions({
title: 'MODIS NDVI Seasonal Profile — Punjab 2023\n(Two peaks = Rabi wheat + Kharif rice)',
hAxis: {title: 'Date'},
vAxis: {title: 'NDVI', minValue: 0, maxValue: 0.9},
lineWidth: 2,
colors: ['#228B22']
});
print(chart);
What you'll see: Two NDVI peaks in Punjab — one in ~March (wheat harvest) and one in ~October (rice harvest). This "double-hump" pattern is the signature of India's most productive agricultural system.
MODIS Land Surface Temperature (LST) — Urban Heat Islands¶
// GEE: Urban Heat Island — MODIS LST
var delhi = ee.Geometry.Rectangle([76.8, 28.4, 77.5, 28.9]);
var lst = ee.ImageCollection("MODIS/061/MOD11A1")
.filterBounds(delhi)
.filterDate('2023-05-01', '2023-05-31') // Peak summer
.select('LST_Day_1km')
.mean()
.multiply(0.02).subtract(273.15); // Convert to Celsius
Map.centerObject(delhi, 10);
Map.addLayer(lst, {min: 30, max: 50, palette: ['blue','yellow','orange','red']},
'LST Delhi May 2023 (°C)');
✏️ Practice Exercise¶
Exercise 5.5 — NDVI Seasonal Profile for Your District
Goal: Plot how vegetation greenness changes through the year in your district.
- In GEE, modify the Punjab code above with your district's coordinates
- Run it for 2023 — you'll get a chart showing NDVI month by month
Interpret the chart: - [ ] How many NDVI peaks are there? (1 peak = single crop, 2 peaks = double crop) - [ ] When is the peak NDVI? (corresponds to the main crop season) - [ ] How low does NDVI drop in the dry season? (indicates how barren the land is) - [ ] Compare your district with a neighbouring district that has different agriculture
Continue to Chapter 6: APIs & Web Services →