Geography of Flood Plain.

A floodplain is a flat or gently sloping area of land adjacent to a river, stream, or other water body that is prone to flooding. Floodplains are created by the natural process of erosion and deposition of sediments carried by water over time. They are an important part of a river's ecosystem and are home to a variety of plant and animal species that have adapted to the regular flooding.

Floodplains are characterized by their relatively flat topography and are often covered with fertile soils that are ideal for agriculture. As a result, many floodplains are heavily populated and developed with homes, businesses, and infrastructure such as roads and bridges.

However, floodplains are also highly susceptible to flooding, which can cause extensive damage to property and infrastructure, as well as endanger human lives. Floods occur when water levels in rivers and streams rise above their normal levels, and this can happen due to heavy rainfall, snowmelt, or other factors.

To minimize the risk of flooding and its associated hazards, floodplain management is an important aspect of land use planning. This includes measures such as building levees and floodwalls, zoning regulations, and land use restrictions that limit development in flood-prone areas. Additionally, some communities have implemented flood warning systems and emergency response plans to help protect residents and property during a flood event.

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Quantitative Revolution in Geography

The Quantitative Revolution was a major change in Geography during the 1950s and 1960s. It introduced mathematical, statistical and scientific methods to understand geographical phenomena. Before this revolution, geographers mainly described places, regions, landscapes and differences between areas. After the revolution, they increasingly used numerical data, statistical analysis, mathematical models and theories to explain why geographical patterns occur and how they may change. For example: Traditional approach: Describe the distribution of population in different regions. Quantitative approach: Use statistical methods to identify population patterns, explain the factors influencing population distribution and predict future population growth. The revolution helped establish Geography as a spatial science, focusing on the location, distribution, relati...

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Spectral Signature vs. Spectral Reflectance Curve

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RADIOMETRIC CORRECTION

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Geometric Correction

When satellite or aerial images are captured, they often contain distortions (errors in shape, scale, or position) caused by many factors — like Earth's curvature, satellite motion, terrain height (relief), or the Earth's rotation . These distortions make the image not properly aligned with real-world coordinates (latitude and longitude). 👉 Geometric correction is the process of removing these distortions so that every pixel in the image correctly represents its location on the Earth's surface. After geometric correction, the image becomes geographically referenced and can be used with maps and GIS data. Types 1. Systematic Correction Systematic errors are predictable and can be modeled mathematically. They occur due to the geometry and movement of the satellite sensor or the Earth. Common systematic distortions: Scan skew – due to the motion of the sensor as it scans the Earth. Mirror velocity variation – scanning mirror moves at a va...

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