Category: Geographic Information System
-
Components of GIS
A Geographic Information System (GIS) is a computer-based system used for capturing, storing, analysing and displaying spatial and non-spatial data. For the effective functioning of a GIS, several components work together to process and manage geographic information. The major components of GIS include computer hardware, software, data, people and methods.…
-
How to Add Google Earth Imagery in QGIS (Satellite & Hybrid)
High-resolution background imagery is essential for creating professional maps. While QGIS comes with OpenStreetMap by default, most users prefer Google Earth Satellite imagery for its detail and clarity. Here is the quickest way to add it using XYZ Tiles (no plugins required). 1. The Magic URLs To stream Google Maps…
-
How to Calculate NDWI & MNDWI in QGIS
If you are mapping water bodies, NDWI (Normalized Difference Water Index) and MNDWI (Modified NDWI) are the two most essential indices. While NDWI is great for general water detection, it often mistakes buildings for water. MNDWI fixes this by using Shortwave Infrared (SWIR) to suppress noise from built-up areas. 1.…
-
How to Calculate NDVI in QGIS Using Landsat Data
Normalized Difference Vegetation Index (NDVI) is the go-to metric for analyzing vegetation health. It uses the difference between Near-Infrared (NIR) and Red light to quantify greenery. If you are using Landsat data in QGIS, here is the fastest way to calculate it. The Formula The general formula for NDVI is:…
-
How to Create Composite Bands (TCC & FCC) in QGIS
Satellite imagery often comes in separate grayscale bands. To visualize them in color or highlight features like vegetation, you need to combine them into composites. Here is the quick workflow for Landsat 8 data in QGIS. The Basics Step 1: Stack the Bands Instead of working with separate files, merge…
-
How to Download Landsat Satellite Data from USGS Earth Explorer
Remote sensing has transformed the way we observe our planet, and one of the most valuable sources of open satellite imagery is the Landsat program. Managed jointly by NASA and USGS, Landsat has been capturing Earth’s surface since 1972, making it the longest continuous Earth observation program in history. Each…
-
Calculate Land Surface Temperature (LST) in QGIS
One of the common applications of thermal RS is estimation of land surface temperature (LST). LST is the radiative temperature of the earth surface, i.e., land derived from solar radiation. When land interact with incoming solar radiation, the ground is heated, and eventually radiate/emit EMR. LST measures the emission of…
-
How to Download SRTM Digital Elevation Model (DEM)
A Digital Elevation Model (DEM) is a 3D representation of a terrain’s surface created from elevation data. DEMs are widely used in hydrology, geomorphology, disaster management, watershed analysis, 3D visualization, relief mapping, and surface modeling. Shuttle Radar Topography Mission (SRTM) DEM data, produced by NASA and USGS, provides high-resolution global…
-
Difference Between Remote Sensing and GIS
Are you curious about the fascinating world of geospatial technology but find yourself puzzled by terms like Remote Sensing and GIS? Don’t worry, you’re not alone! In this blog post, we’ll unravel the fundamental differences between Remote Sensing and GIS in simple terms, helping you understand how these two technologies…