Course Handout Remote Sensing and GIS : For the students of the 3rd Year Bachelor's Degree in Ecology and Environment

Abstract

Remote Sensing and Geographic Information Systems (GIS) are transformative technologies that have revolutionized the way we collect, analyze, and interpret spatial and environmental data. These tools are fundamental in understanding Earth's physical features, processes, and the impact of human activities. Remote sensing refers to the acquisition of data about an object or phenomenon without making physical contact, often through satellites or airborne sensors. It enables the observation of large and inaccessible areas, providing valuable insights into land use, vegetation, urban planning, and environmental monitoring. Remote sensing originated from the merging of two ancient inventions: the hot air balloon (the first aerial observation platform) and photography. In reality, modern remote sensing emerged from aerial photography, which saw significant development during the 20th century, especially during World War II. The year that symbolizes the entry of remote sensing into the modern era is 1957 with the launch of Sputnik, the first artificial satellite placed in orbit around the Earth. Since then, many countries, including the USA, Canada, France, the former USSR (now Russia), China, Japan, and India, have developed their own remote sensing programs. Today, dozens of Earth observation satellites are in orbit, continu0ously providing thousands of images for civil applications. A satellite observes a region of the Earth in a very different way. It does not have a camera on board, but instruments that are 'sensitive' to visible light, as well as other parts of the 'electromagnetic spectrum' such as infrared, ultraviolet, or microwaves. These instruments (scanners) scan the Earth's surface and record measurements of 'light,' which are then used by computer programs to create images. Geographic Information Systems (GIS), on the other hand, are powerful platforms for storing, managing, and analyzing spatial data. GIS integrates various data types—such as maps, satellite images, and sensor data—allowing users to visualize, interpret, and analyze patterns and trends within a geographic context. Through GIS, complex spatial relationships can be explored, leading to more informed decision-making in areas like urban planning, disaster management, agriculture, and natural resource management.