Earth is a spherical (not exactly but let’s consider!) surface. This spherical surface is also termed as spheroid or ellipsoid. It has always been a challenging job to specify the location and shape of a particular feature on the earth surface. In order to solve this issues the geographer and cartographer came up with an …
What is a Map Projection? What are different Map Projections used in GIS? Read More »
Background This article is inspired by a book by Gina Clemmer, “The GIS 20 Essential Skills” published by ESRI in 2017. This book offers an activation code for free GIS trail for 180-days, so it’s worth buying this book. First thing first, you need to have basic knowledge on GIS in order to learn these …
Want to become GIS expert: Master these 20 Essential GIS Skills. Read More »
It has always been a popular question – What are the differences between shapefile and feature class? Here, are differences and similarities between Shapefiles and Feature class. What are feature classes? A feature class is a collection of geographic features that share the same geometry type (such as point, line, or polygon) and the same …
What are the similarities and differences between Shapefile and Feature Class? Read More »
Definition Shapefiles are spaghetti data models containing a features class composed of points, lines, or polygons, but never a mixture. The attributes are stored in dBase file. Shapefiles can store multipart features, in which a single feature includes multiple objects. Shapefile components and file extensions Shapefiles are stored in three or more files that all …
Definition A feature class is a collection of geographic features that share the same geometry type (such as point, line, or polygon) and the same attribute fields for a common area. Examples: streets, well points, parcels, soil types, and census tracts etc. A feature class can contain only one kind of geometry—point, line, or polygon …
What is an Atmospheric Correction? As name suggest, atmospheric correction is the process of removing the effects of the atmosphere on the reflectance values of remotely sensed images. The atmospheric effects may be referred to as presence of gas absorption, molecule and aerosol scattering that can influence incident and reflected radiation the atmosphere can have …
What is an Atmospheric Correction and why is it necessary? Read More »
Forewords As a researcher, it is always troublesome to find right datasets for right projects. It could be more infuriating when you lose the websites that you’ve been downloading the data from. The best idea is to bookmark the important websites so that you will never loose them. Check these websites to “Download GIS Data by …
Important Sites to Download Freely Available GIS Datasets – In the USA Read More »
As a researcher, it is always troublesome to find right datasets for right projects. It could be more infuriating when you lose the websites that you’ve been downloading the data from. The best idea is to bookmark the important websites so that you will never loose them. Check these websites to “Download GIS Data- Global” …
Important Sites to Download Freely Available GIS Data-sets Across the World! Read More »
Remote Sensing and GIS are two different terms however, people seem to have used them interchangeably. Remote Sensing is a field which deals with acquiring, interpreting, and analyzing remotely sensed imagery particularly Landsat, MODIS, Sentinel, or even Lidar data whereas GIS is a tool that helps in this process. Before learning the importance of GIS …
What is the importance of GIS (Geographic Information Science) in Remote Sensing? Read More »
Before we jump into the differences between Geographic and Projected Coordinate Systems, let’s learn about coordinate systems. Coordinate System In general term, A coordinate system is a method for identifying the location of a point on the earth. The coordinate systems use two numbers— (x and y) or (latitude and longitude) commonly known as a …
What are the differences between Geographic and Projected Coordinate Systems? Read More »