37 Remote Sensing Applications and Uses

37 Remote Sensing Applications and Uses

 

1. Determining soil moisture content using active and passive sensors from space

To understand earth science, contribution of soil moisture is so much. For example, it explains Earth’s water cycle, weather forecasting, drought and floods. But did you know there are two ways to derive soil moisture from space? First, it uses passive and active sensors. Active sensors like Sentinel-1, Radarsat-2 illuminate their target and measures backscatter. In turn, this results in high spatial resolution but low accuracy. Second, passive sensors like SMOS measures naturally emitted microwave radiation. Unlike active sensors, it gives highly accurate but poor spatial resolution. How can we get the best of both worlds? This is what NASA’s Soil Moisture Active Passive (SMAP) Mission strives to achieve.

 

2.  Mapping with laser precision using Light Detection and Ranging technology

LiDAR measures the distance from the airborne platform to Earths surface using laser beams. This is how LiDAR got its name – “Light Detection and Ranging”. What makes LiDAR so special is its densely sampled points at laser accuracy. LiDAR generates point clouds for digital surface models, digital elevation models and light intensity models.

3. Flood Monitoring According to Sentinel-1 Radar Imagery

Monitoring flooded areas and tracking the water levels in reservoirs are very important, due to their potential impacts. Tracking this can be easier using remote sensing, i.e. space images made by both optical and radar scanners. Unfortunately, in bad weather conditions, the monitoring process can be impeded by dense clouds as they greatly reduce the value of the optical images. In such case, radar imagery becomes more useful than optical. Radar works by sending out a signal and it reflects back to the satellite from the Earth, so it does not depend on cloudiness or lighting.

4. Crop production forecasting

Remote sensing is used to forecast the expected crop production and yield over a given area and determine how much of the crop will be harvested under specific conditions. Researchers can be able to predict the quantity of crop that will be produced in a given farmland over a given period of time.

5. Crop type classification

Remote sensing technology can be used to prepare maps of crop type and delineating their extent. Traditional methods of obtaining this information are census and ground surveying. The use of satellites is advantageous as it can generate a systematic and repetitive coverage of a large area and provide information about the health of the vegetation. The data of crop is needed for agricultural agencies to prepare an inventory of what was grown in certain areas and when. This information serves to predict grain crop yield, collecting crop production statistics, facilitating crop rotation records, mapping soil productivity, identification of factors influencing crop stress, assessment of crop damage and monitoring farming activity.

6. Soil mapping:

Soil mapping is one of the most common yet most important uses of remote sensing. Through soil mapping, farmers are able to tell what soils are ideal for which crops and what soil require irrigation and which ones do not. This information helps in precision agriculture.

7. Land cover mapping

Land cover mapping is one of the most important and typical applications of remote sensing data. Land cover corresponds to the physical condition of the ground surface, for example, forest, grassland, concrete pavement etc., while land use reflects human activities such as the use of the land, for example, industrial zones, residential zones, agricultural fields etc Initially the land cover classification system should be established, which is usually defined as levels and classes. The level and class should be designed in consideration of the purpose of use (national, regional or local), the spatial and spectral resolution of the remote sensing data, user's request and so on.

Land cover change detection is necessary for updating land cover maps and the management of natural resources. The change is usually detected by comparison between two multi-date images, or sometimes between an old map and an updated remote sensing image.seasonal change:agricultural lands and deciduous forests change seasonally

§       annual change: land cover or land use changes, which are real changes, for example deforested areas or newly built towns.

Information on land cover and changing land cover patterns is directly useful for determining and implementing environment policy and can be used with other data to make complex assessments (e.g. mapping erosion risks).

8. Weather forecasting:

Remote sensing technology is ideal for collection and storing of past and current weather data which can be used for future decision making and prediction.

9. Air moisture estimation: 

Remote sensing technology is used in the estimation of air moisture which determines the humidity of the area. The level of humidity determines the type of crops to be grown within the area.

10. Air Quality monitoring:

Some cities are so polluted that it’s the equivalent of smoking a package of cigarettes each day. 80% of these over-polluted cities are in China. One of the major pollutants is carbon monoxide. Carbon monoxide is colorless to the human eye but not for MOPITT (Measurements of Pollution in the Troposphere) on NASA’s Terra satellite. MOPITT uses a spectrometer to measure upwelling infrared radiation in the lower atmosphere.

11. Studying glacier melts and effects on sea levels

Glaciers hold the largest freshwater reservoir on Earth. You can find 99% of glaciers in the Polar Regions. NASA’s GRACE satellite showed that the Alaskan glaciers were losing mass at about 20.6 gigatonnes per year. But the scary takeaway is the rapid melting ice and its profound effects on sea levels.

12. Observing the flow of ocean currents and circulation

Water covers 71% of the Earth with most of it in oceans. And ocean currents connect all oceans mainly driven by winds at the surface. But deep below the surface, salinity and temperature control currents. Satellites can achieve an enormous wealth of information on ocean currents and circulation. Ocean Surface Current Analyses – Real Time (OSCAR) is a near real-time global ocean circulation data set based on NOAA and NASA’s sea level altimetry, surface winds and sea surface temperature.

13. Crop conditions monitoring through NDVI (Normalized Difference Vegetation Index)

Satellite imagery help us to monitoring the global food supply and the Normalized Difference Vegetation Index (NDVI). Near-infrared radiation is being used to detect healthy vegetation in agriculture. Healthy vegetation absorbs red and blue light and reflects green light. The green light that our eyes see is chlorophyll created by plants during photosynthesis. Chlorophyll will reflect more light in the green and near infrared spectrum compared to other wavelengths. This is why near infrared radiation in combination with NDVI is one of the primary remote sensing applications in agriculture and the environment.

14. Preventing the loss of wetland ecosystems and degradation

Once seen as a nuisance in agriculture, wetlands are being drained and lost. Suddenly, they have become a rare precious resource. Wetlands serve many purposes. They help purify water, control flooding and improve shoreline stability. This is why remote sensing applications to inventory wetlands have grown so much over the years.

15. Measuring gravity with the GRACE satellites

This may be one of the neatest remote sensing applications on the list – measuring gravity. NASA’s Gravity Recovery and Climate Experiment (GRACE)consists of two satellites in the same orbit approximately 220 kilometers apart. When the leading satellite increases speed, this means there is a greater gravitational pull. If the leading satellite slows down, this means there is less gravitational pull. These pulls in gravity are measured using microwave pulses from one satellite to the other. The end result is the most accurate measurements of gravity to this date.

16. Comparing the past and present with human impact change

The Landsat missions are the longest-running Earth observation missions ever. Its digital records date back to the 1970s. If we want to understand landscape change, the Landsat missions give us a snapshot back in time. We can learn from the past for future generations. Oil spills, deforestation, wars, chemical spills, dead zones, smog are unnatural, man-made disasters. All are preventable and can be viewed from space. 

17. Planning an optimal telecom network capacity

87% of the world population now use mobile devices. The astounding rate of growth in this industry requires extensive planning for optimal network capacity. Telecommunications companies are using remote sensing as a cost-effective way to optimize capacity requirements. Radio frequency coverage can be augmented with the appropriate antenna type, location and direction. Satellite-derived terrain, land use and other environmental factors can be modeled to achieve optimal network capacity.

18. Helping provide clean drinking water with base maps

Water is life’s most basic need. But nearly 1 billion people live without clean drinking water. The first step in solving this problem is identifying areas that are in need of water. High spatial resolution satellite imagery can really differentiate where water shortages exist. This is the starting point to an action plan. Simple remote sensing applications like base maps can positively affect the lives of millions by establishing where and who is in need of essential resources like water.

19. Monitoring active volcanoes using thermal remote sensing

There are over 600 active volcanoes on Earth. Volcanoes form when hot molten rock from the upper mantle finds its way to the surface. Eruptions are dangerous to humans and the surrounding environment. Volcanoes are often inaccessible (unless you are Mario or Luigi, Mario and Luigi are two fictional characters from Nintendo's Mario video game franchise) making remote sensing applications like thermal and mid-infrared clear solutions for understanding volcano activity. AVHRR and MODIS are prime candidates for volcano monitoring.

20. Inventorying potential landslides with interferometry

Landslides are often under-represented for hazard research. But every year in the INDIA, landslides cause loss of life and billions of dollars in damage. The major landslide prone areas in India include the Western Ghats and Konkan Hills (Tamil Nadu, Kerala, Karnataka, Goa and Maharashtra), Eastern Ghats (Arakuregion in Andhra Pradesh), North-East Himalayas (Darjeeling and Sikkim) and North West Himalayas (Uttarakhand, Himachal Pradesh, Jammu and Kashmir).

The first step in inventorying potential landslides is using stereo and optical images with slope. Slope instability triggers can be a number of things – earthquakes, erosion, poor drainage and more. InSAR can provide early warning signs for landslides because how well it measures ground surface displacements.

21. Catching fish and improving long-term fisheries sustainability

There are plenty of fish in the sea from a satellites viewpoint. Satellites monitor sea surface temperature and ocean colors because they are indicative of specific fish species. The top-down view of remotely sensed data can be communicated with local fisherman. Fishermen use this information to save time and fuel in real-time. In terms of remote sensing applications in fisheries and marine environment, algal blooms can be mapped which are harmful to aquaculture. This improves overall long-term sustainability.

22. Tracking the great distances of migratory birds and inspecting their prevalence

Birds travel great distances in search of food, climate and breeding sites. Light-weight GPS telemetry is just one of the tools being used to know where birds migrate. As forests become more limited, migration patterns are important for wildlife managers. Remote sensing applications like LiDAR, multispectral and radar can show forest properties like vertical structure and phenology. Habitat suitability models predict the prevalence of bird species using these forest properties.

23. Obstructing the spread of diseases in epidemiology

The birth of epidemiology came shortly after Jon Snow mapped the spread of cholera from a contaminated pipe in 1854. Ironically, this was also the birth of Geographic Information Systems. There is a clear connection for epidemiology and geography. Some diseases are best-suited for climate, land use and air. Remote sensing applications in health use these remote sensing data and prediction models to understand epidemiological processes.

24. Application of remote sensing data in earthquake monitoring

The result of an earthquake can be catastrophic and at times difficult to assess. But an earthquake assessment is essential for rescue workers. They need to be done quickly and with accuracy. Object-based image classification using change detection (pre- and post-earthquake) is a quick way to get damage assessments. Other remote sensing applications in disaster assessments include casted shadows from buildings and digital surface models.

25. Mapping the mysteries of our ocean floors

In this day and age, we have most of the world mapped. The world is at our fingertips with a wide range of open source mapping applications. The next challenge is mapping the ocean floor. ESA’s CryoSat-2 and NASA’s Jason-1 satellites have pieced together the most complete picture of our ocean floor and subfloor features. The pull of gravity reveals underwater mountains and seafloor topography.

26. Understanding the human rights situation in North Korea

Remote sensing can give an in-depth look at hermit kingdoms like North Korea. Remote sensing enables what some travellers may never get to see in their lifetime. Ostrich farms, breweries, towers – all uniquely North Korean. But satellites also enable to see the darker side of North Korea. For those wanting to escape North Korea, they are sent to prison camps. These camps are clearly seen from the skies.

27. Monitoring the global sex trade situation in remote areas

The global sex trade is a growing international crime where one’s rights are violated through commercial exploitation. Often involuntary, the flow of human trafficking has been tracked using the latest satellite imagery from NASA. The flow of human trafficking often crosses boundaries and done secretively. Remote sensing makes it possible to overcome these barriers and provide evidence for human trafficking globally.

28. Studying geology of the Earth’s surface

Geology is one of the rare things that stays constant in our lives. Every landscape, plant and animal we see today are affected by the rocks, material and nutrients. All have an origin from geology. Some of the remote sensing applications in geology include bedrock, lithological and structural mapping. Multispectral spectral reflectance has provided valuable information on rock composition while radar has also been useful in studying surface roughness.

29. Assessing the environmental change and promoting biodiversity in parks

There’s no kidding around of the importance of parks. Parks provide a home for a large number of animals and species at risk. They often prohibit development and are used for camping and recreation. Parks can be large in scale making them a difficult resource to manage. Remote sensing data gathered over time can show landscape change. Some remote sensing applications in parks include mapping biodiversity, invasive species and forest fire risk.

30. Measuring albedo for Earth’s radiation budget

Albedo measures the percent of reflected sunlight. A darker surface will heat up quickly and absorb sunlight. Brighter surfaces like snow reflect much sunlightback to the atmosphere. Albedo is a key component in the Earth’s radiation budget. In order to calculate total albedo, each land cover type is assigned an albedo value. Multiply albedo with the land cover type and sum to measure total albedo.

31. Locating groundwater activity for wells

Earth is surrounded by water in the form of oceans, rivers and lakes. At the ground below your feet is even more water in the form of groundwater. An aquifer stores groundwater. There are thousands of wells that draw water from aquifers. This water is being used in agriculture, drinking water and more. This is why it’s important to have good spatial knowledge of groundwater. Groundwater activity can be understood by its rock types, soil, land use and rainfall. Remote sensing groundwater prospect zone maps are used to locate well sites.

32. Delineating watersheds using DEMs for hydrologists

A digital elevation model determines where and how water flows in a watershed. Hydrologists are interested in the hydrologic budget when they study watersheds. Inputs are precipitation, surface flow and groundwater flow. Outputs are evapotranspiration, infiltration and surface runoff. Remote sensing contributes to watershed delineation by providing accurate elevation data. Digital elevation models are used to accurately represent stream flow paths and the contributing areas with software systems like HEC and Geo-HMC.

33. Using habitat suitability models to predict the abundance of mosquitoes

Habitat suitability models are making some interesting predictions on the abundance of mosquitoes. Remotely-sensed factors such as greenness, brightness, temperature and especially moisture positively correlate with the over-occurrence of mosquitoes. Knowing the location of high concentrations of mosquitoes can guide risk assessment for disease carrying pathogens and mosquito fogging efforts.

34. Improving efficiency and safety of air traffic control

Air traffic control directs aircrafts from the ground to prevent collision and improve the flow of traffic. Unfortunately, there are excessive dollars and emissions wasted on inefficient routes. The next generation of air traffic moves from ground-based radar to a satellite-based GPS system. The new air traffic control system aims at improving routes, reducing traffic delays and saving money. It also intends to assist planes land faster and help navigate through weather with the use of satellites.

35. Reducing traffic jams using change detection

Our increasing populations and urbanization has led to increasing amounts of traffic in urban centres. Traffic jams mean wasted fuel and time. Ground measuring systems provide extremely precise traffic volumes but it’s limited to selected roadways. Traffic density is being monitored using change detection. Traffic analysts can compare two satellite images with slight lags. This shows traffic movement over a larger picture.

36. Measuring the rise of sea levels

Every year Venice is sinking a little more. Measuring the rise of sea levels is a perfect example of a large-scale application done in a cost-effective manner. There is no need to go on the beach and bring out your measuring stick at sea level all along the coast. In order to understand sea level rise, you need good baseline spatial data. Measuring sea level rise is a function of time with centimetre accuracy measurements using remote sensing data.

37. Exploring, protecting and navigating in the arctic

Things are kind of in flux now for ‘who’ is claiming ‘what’ in the Arctic. The US, Russia, Canada and Danish are all staking their territory. But no one can tap the Arctic until all countries come to an agreement. Mineral extraction, natural gas, as well as potential shortcuts for shipping routes – the Arctic may be one of the last great frontiers for human development. Heavy duty tasks like sea ice monitoring, ship tracking and national defence makes satellites a heaven-sent opportunity for maintaining sovereignty in the North.