The following points highlight the nine main applications of remote sensing. The applications are: 1. Uses of Remote Sensing at Farm 2. Agricultural Applications of Remote Sensing 3. Forestry Applications of Remote Sensing 4. Geological Applications of Remote Sensing 5. Hydrological Applications of Remote Sensing 6. Sea Ice Applications of Remote Sensing and Few Others.

Remote sensing refers to the process of sensing and measuring objects from distance without directly coming physically in to contact with them. When farmers or ranchers observe their fields or pastures to assess their condition without physically touching them, it is a form of remote sensing.

Observing the colours of leaves or the overall appearances of plants can determine the plant’s condition. Remotely sensed images taken from satellites and aircraft provide a means to assess field conditions without physically touching them from a point of view high above the field.

It is the use of magnetic radiation sensors for making the images of environment, whose analysis is utilized for useful information. This is being used in environmental science, geography, geology, botany, civil engineering, agriculture, forestry, meteorology and oceanography.

Most remote sensors see the same visible wavelengths of light that are seen by the human eye, although in most cases remote sensors can also detect energy from wavelengths that are undetectable to the human eye.

The remote view of the sensor and the ability to store, analyze, and display the sensed data on field maps are what make remote sensing a potentially important tool for agricultural producers. Agricultural remote sensing is not new and dates back to the 1950s, but recent technological advances have made the benefits of remote sensing accessible to most agricultural producers.

1. Uses of Remote Sensing at Farm:

Remotely sensed images can be used to identify nutrient deficiencies, diseases, water deficiency or surplus, weed infestations, insect damage, hail damage, wind damage, herbicide damage, and plant populations.

Information from remote sensing can be used as base maps in variable rate applications of fertilizers and pesticides. Information from remotely sensed images allows farmers to treat only affected areas of a field. Problems within a field may be identified remotely before they can be visually identified.

Ranchers use remote sensing to identify prime grazing areas, overgrazed areas or areas of weed infestations. Lending institutions use remote sensing data to evaluate the relative values of land by comparing archived images with those of surrounding fields.

2. Agricultural Applications of Remote Sensing:

Agriculture plays a dominant role in economies of both developed and undeveloped countries. Satellite and airborne images are used as mapping tools to classify crops, examine their health and viability, and monitor farming practices.

Agricultural applications of remote sensing include the following:

i. Crop type classification

ii. Crop condition assessment

iii. Crop yield estimation

iv. Mapping of soil characteristics

v. Mapping of soil management practices

vi. Compliance monitoring (farming practices)

3. Forestry Applications of Remote Sensing:

Forests are a valuable resource providing food, shelter, wildlife habitat, fuel, and daily supplies such as medicinal ingredients and paper. Forests play an important role in balancing the Earth’s CO2 supply and exchange, acting as a key link between the atmosphere, geosphere, and hydrosphere.

Forestry applications of remote sensing include the following:

i. Reconnaissance Mapping:

Objectives to be met by national forest/environment agencies include forest cover updating, depletion monitoring, and measuring biophysical properties of forest stands.

ii. Commercial Forestry:

Of importance to commercial forestry companies and to resource management agencies are inventory and mapping applications: collecting harvest information, updating of inventory information for timber supply, broad forest type, vegetation density, and biomass measurements.

iii. Environmental Monitoring:

Conservation authorities are concerned with monitoring the quantity, health, and diversity of the Earth’s forests.

4. Geological Applications of Remote Sensing:

Geology involves the study of landforms, structures, and the subsurface, to understand physical processes creating and modifying the earth’s crust. It is most commonly understood as the exploration and exploitation of mineral and hydrocarbon resources, generally to improve the conditions and standard of living in society.

Geological applications of remote sensing include the following:

i. Surface deposit/bedrock mapping

ii. Lithological mapping

iii. Structural mapping

iv. Sand and gravel (aggregate) exploration/exploitation

v. Mineral exploration

vi. Hydrocarbon exploration

vii. Environmental geology

viii. Geobotany

ix. Baseline infrastructure

x. Sedimentation mapping and monitoring

xi. Event mapping and monitoring

xii. Geo-hazard mapping

xiii. Planetary mapping

5. Hydrological Applications of Remote Sensing:

Hydrology is the study of water on the Earth’s surface, whether flowing above ground, frozen in ice or snow, or retained by soil.

Examples of hydrological applications include:

i. Wetlands mapping and monitoring,

ii. Soil moisture estimation,

iii. Snow pack monitoring/delineation of extent,

iv. Measuring snow thickness,

v. Determining snow-water equivalent,

vi. River and lake ice monitoring,

vii. Flood mapping and monitoring,

viii. Glacier dynamics monitoring (surges, ablation)

ix. River/delta change detection

x. Drainage basin mapping and watershed modelling

xi. Irrigation canal leakage detection

xii. Irrigation scheduling

6. Sea Ice Applications of Remote Sensing:

Ice covers a substantial part of the Earth’s surface and is a major factor in commercial shipping and fishing industries, Coast Guard and construction operations, and global climate change studies.

Examples of sea ice information and applications include:

i. Ice concentration

ii. Ice type/age/motion

iii. Iceberg detection and tracking

iv. Surface topography

v. Tactical identification of leads: navigation: safe shipping routes/rescue

vi. Ice condition (state of decay)

vii. Historical ice and iceberg conditions and dynamics for planning purposes

viii. Wildlife habitat

ix. Pollution monitoring

x. Meteorological/global change research

7. Land Use Applications of Remote Sensing:

Although the terms land cover and land use is often used interchangeably, their actual meanings are quite distinct. Land cover refers to the surface cover on the ground, while land use refers to the purpose the land serves. The properties measured with remote sensing techniques relate to land cover, from which lend use can be inferred, particularly with ancillary data or a priori knowledge.

Land use applications of remote sensing include the following:

i. Natural resource management

ii. Wildlife habitat protection

iii. Baseline mapping for GIS input

iv. Urban expansion/encroachment

v. Routing and logistics planning for seismic/exploration/resource extraction activities

vi. Damage delineation (tornadoes, flooding, volcanic, seismic, fire)

vii. Legal boundaries for tax and property evaluation

viii. Target detection – identification of landing strips, roads, clearings, bridges, land/water interface

8. Mapping Applications of Remote Sensing:

Mapping constitutes an integral component of the process of managing land resources, and mapped information is the common product of analysis of remotely sensed data.

Mapping applications of remote sensing include the following:

i. Planimetry:

Land surveying techniques accompanied by the use of a GPS can be used to meet high accuracy requirements, but limitations include cost effectiveness, and difficulties in attempting to map large, or remote areas. Remote sensing provides a means of identifying and presenting planimetric data in convenient media and efficient manner.

Imagery is available in varying scales to meet the requirements of many different users. Defence applications typify the scope of planimetry applications – extracting transportation route information, building and facilities locations, urban infrastructure, and general land cover.

ii. Digital Elevation Models (DEM’s):

Generating DEMs from remotely sensed data can be cost effective and efficient. A variety of sensors and methodologies to generate such models are available and proven for mapping applications.

Two primary methods if generating elevation data are:

1. Stereogrammetry techniques using airphotos (photogrammetry), VIR imagery, or radar data (radargrammetry), and

2. Radar interferometry.

iii. Baseline Thematic Mapping/Topographic Mapping:

As a base map, imagery provides ancillary information to the extracted planimetric or thematic detail. Sensitivity to surface expression makes radar a useful tool for creating base maps and providing reconnaissance abilities for hydrocarbon and mineralogical companies involved in exploration activities.

This is particularly true in remote northern regions, where vegetation cover does not mask the microtopography and generally, information may be sparse. Multispectral imagery is excellent for providing ancillary land cover information, such as forest cover. Supplementing the optical data with the topographic relief and textural nuance inherent in radar imagery can create an extremely useful image composite product for interpretation.

9. Ocean Applications of Remote Sensing:

The oceans not only provide valuable food and biophysical resources, they also serve as transportation routes, are crucially important in weather system formation and CO2 storage, and are an important link in the earth’s hydrological balance.

Coastlines are environmentally sensitive interfaces between the ocean and land and respond to changes brought about by economic development and changing land-use patterns. Often coastlines are also biologically diverse inter-tidal zones, and can also be highly urbanized.

Ocean applications of remote sensing include the following:

i. Ocean pattern identification

ii. Currents, regional circulation patterns, shears

iii. Frontal zones, internal waves, gravity waves, eddies, upwelling zones, shallow water bathymetry

iv. Storm forecasting

v. Wind and wave retrieval

vi. Fish stock and marine mammal assessment

vii. Water temperature monitoring

viii. Water quality

ix. Ocean productivity, phytoplankton concentration and drift

x. Aquaculture inventory and monitoring

xi. Oil spill

xii. Mapping and predicting oil spill extent and drift

xiii. Strategic support for oil spill emergency response decisions

xiv. Identification of natural oil seepage areas for exploration

xv. Shipping

xvi. Navigation routing

xvii. Traffic density studies

xviii. Operational fisheries surveillance

xix. Near-shore bathymetry mapping

xx. Intertidal zone

xxi. Tidal and storm effects

xxii. Delineation of the land/water interface

xxiii. Mapping shoreline features/beach dynamics

xxiv. Coastal vegetation mapping

xxv. Human activity/impact