Remote sensing involves obtaining information about an object or area through analysis of data from a device not in direct contact. It uses electromagnetic radiation and various sensors to capture images. Atmospheric factors like absorption and scattering can influence images. Images have spatial, spectral, and radiometric resolution as well as temporal resolution. Interpretation examines shape, size, patterns, tones, textures, and shadows. Applications include land use mapping, geology, agriculture, forestry, wetlands, archaeology, and more. Remote sensing provides improved perspectives, permanent records, and access to inaccessible areas to assess natural resources.

1. INTRODUCTION
TO
REMOTE SENSING

2. Remote sensing is the science and art
of obtaining information about an
object, area, or phenomenon through
the analysis of data acquired by a
device that is not in contact with the
object, area or phenomenon under
investigation.

3. Electro Magnetic Radiation
Q = h f = h c/λ ( The energy of a quantum )
M = σ T4 ( Stefan-Boltzman law )
λm = A/T ( Wien’s displacement law )

4. Atmospheric Influences
Absorption
Scattering
Rayleigh scatter
Mie scatter
Nonselective scatter

7. Image Acquisition
Photographic Sensors
Digital Data
Earth Resource Satellites

8. Image Resolution
Spatial resolution
Spectral resolution
Radiometric resolution
Temporal resolution

9. Image Interpretation
Shape
Size
Pattern
Tone (Hue)
Texture
Shadows
Site
Association

10. Applications
Land Use/Land Cover Mapping
Geologic and Soil Mapping
Agricultural Applications
Forestry Applications
Rangeland Applications
Urban and Regional Planning Applications
Wetland Mapping
Wildlife Ecology Applications
Archaeological applications
Environmental Assessment
Oil Exploration
Mineral Exploration
Landforms Identification and Evaluation
Water Resource Applications etc.

11. Conclusions
A picture is worth a thousand words, because pictures concisely convey
information about positions, size, and interrelationships between objects.
The basic advantages of images over the ground observation are i)
Improved vantage point, ii) Capability to stop action, iii) Permanent
recording, iv) Broadened spectral sensitivity, v) Increased spatial resolution
and geometric fidelity, vi) providing data for inaccessible regions etc.
Remote sensing will continue to play an increasingly broad and important
role in natural resources management. The technical capabilities of sensors,
space platforms, data communication systems, GPSs, digital image
processing systems, and GISs are improving on almost a daily basis. At the
same time, we are witnessing an evolution of various remote sensing
procedures from being purely research activities to being commercially
available services. Most importantly, we are becoming increasingly aware
of how interrelated and fragile the elements of our global resource base
really are and of the role remote sensing can play in inventorying,
monitoring, and managing earth resources and in modeling and helping us
understand the global ecosystem.