As long as the sudden and gradual occurrence of Natural Hazards or disasters have always been one of the humanity’s challenges throughout history and they are so important that have sometimes changed the destiny of many nations, humans have been trying to cope with them by assessing these natural phenomena and reducing their occurrence risks.
Although humans play minor roles in the occurrence or severity of natural phenomena, they can ensure that natural events will not become catastrophic due to human activities. It is noteworthy that human intervention can increase the frequency and severity of natural hazards.
Human intervention can even cause the occurrence of natural hazards that have not existed before. Lack of proper reaction can result in ecosystem changes in an area or in the world. Therefore, if human activities have destructive effects on natural phenomena, it will be necessary to prevent these activities or mitigate their effects. To this end, a wide range of measures is now being undertaken at national and international levels to assess these phenomena and mitigate their occurrence risks.
However various methods and techniques have so far developed to design a comprehensive plan for integrated environmental monitoring of different natural phenomena, extensive progress is still needed in this area.
The following key challenges and questions must is: What types of data should be collected for each of these natural phenomena? What are the data collection methods and tools? How to convert a large amount of data on various phenomena into relevant and analytical information? Finally, how can the results of information processing lead to making the right actual decisions for accurate assessment of these phenomena and mitigate their risk as well as their destructive effects? Answering these questions is one of the fundamental challenges of human beings for preparing themselves to cope with predicted and unpredicted risks of these natural phenomena.
Definition and classification of natural hazards
The term “natural hazards” refers to all atmospheric
and geologic phenomena, especially earthquake and volcanic activity, as well as
rapid and widespread fires that have the potential to affect
structures, humans and their activities due to their location, intensity, and
frequency. The word “natural” refers to the mentioned items and it does refer
to human phenomena such as war, pollution, chemical pollution, contagious
diseases and the like. Table 1 provides a simplified list of natural hazards.
Notwithstanding the term “natural”, a natural
hazard has an element of the human environment. A
natural phenomenon such as a volcanic activity that does not affect human life
is considered as a natural phenomenon but not as a natural hazard. A natural
phenomenon occurring in a crowded area is a dangerous event. A dangerous event can result in unacceptable
deaths, severe injuries, and natural disasters.
In low populated areas, natural phenomena neither cause a danger nor
consider as hazard unless the natural phenomena that have global impacts on
earth’s entire ecosystem, such as Amazon rainforest wildfires.
Erosion and sedimentation
(ash, cinders, lapilli)
Projectiles and lateral blasts
Table 1. Provides a simplified list of
Natural hazard assessment and mitigation
In general, there are
four major factors to consider in the assessment of the damages and hazards
from natural phenomena:
- Fast or slow onset
For example, some phenomena such as earthquakes and floods occur
suddenly, while the occurrence of some phenomena, such as drought is a slow process
lasting for a longer period; type of hazards, the likelihood of the
these hazards and the ways they are handled are different.
controllable or unchangeable
Some of these hazards can be controlled if the measurements are
taken appropriately while no technology has an airborne role in preventing the
occurrence of some other hazards.
Intensity and frequency as well as the repetitions of occurrence
of each hazardous phenomenon are among the important parameters for assessment
of the phenomena and being prepared to handle them and reduce their effects.
measures for mitigation of hazard’s effects
Appropriate hazard assessment followed by
control measures to minimize or eliminate their effects will allow
constructions to survive against hazards such as earthquakes or floods.
As a result, one of the main procedures needed to minimize the impact of these threats is to accurately assess their effects through appropriate measurement methods and then take effective processes for risk management.
In this management process, all probabilities and uncertainties associated with hazard occurrence are analyzed in terms of various parameters and the occurrence risk of these phenomena is determined through data analysis. As mentioned, different methods and tools for data collection, information processing and fusion, and making quick and accurate decisions are among the most important and complicated challenges.
So far, the topic has been addressed in general, and hereafter the paper focus will be on “investigating various types of sensors and platforms carrying these sensors for airborne remote sensing, information processing, and fusion as well as decision making techniques”.
Formally, remote sensing is the acquisition of information about an object, area or phenomenon without making physical contact with them by analysis of acquired data . The existing remote sensing technology includes hardware/ software and analytical capabilities for data acquisition and remote data transfer.
Remote data acquisition requires a platform and a set of sensors. Platforms usually are satellites, aircraft, and drones that can carry a set of sensors for data recording. Data processing based on appropriative software tools enables data representation as digital images containing geographical coordinates. Imagery is done using software installed on a stationary or portable computer.
Satellite and UAV imagery has been significantly used in the last few years. However, conventional methods of remote sensing such as imagery from airplanes are still used in emergency measures. One of the major advantages of remote sensing techniques is the observation of a large area from a distance, which could be very costly if done via ground-based methods .
In general, sensors
are classified into two categories: active and passive. For passive sensors,
the source of energy is usually the visible
light spectrum of the sun, self-emitted
thermal radiation or microwave energy. Active sensors such as radars and LiDARs use their own source of energy for detection and monitoring.
Remote sensing in natural hazard assessments
One of the most important available tools for natural hazard assessments is the remote sensing of the environment. The data received from these sensors are not only very valuable in the planning process, but also useful in detecting and mapping many types of natural hazards especially when precise details of their effects are not available.
If these hazards and their probability of occurrence are identified in the initial steps, it will be possible to minimize their effects and consequences through study and measurement. Since all the natural phenomena including terrestrial, marine, and atmospheric phenomena have oscillatory or recursive behaviors or processes, it is possible to study all of these natural hazards via remote sensing.
These studies enable the possibility of recording, analyzing, and integrating the planning process for hazard assessment and subsequent actions. Most remote sensing studies on natural hazards include the regions vulnerable to a natural disaster, monitoring probable events that contribute to the occurrence of a natural disaster as well as the magnitude, expansion, and duration of a natural disaster.
To this end, these studies should, first of all, examine the remote sensing information required for natural hazard assessment and identification. Then, various methods for data collection, interpretation and processing should be determined. Next, the required sensors should be determined depending on the type of required data.
Presently, remote sensing systems e.g. space, atmospheric, terrestrial or under-marine systems, have been developed. Each of these sensors acquires the necessary data depending on their own environment. As mentioned, this study aimed to use different types of sensors to collect data from the environment through airborne remote sensing for assessment, prevention, and control of rainforest wildfires. These important points should be considered in designing a remote sensing system:
utilization of remote sensing data depends on the ability, attentiveness, and logic of the
operator in interpreting images, graphs or statistical data extracted from
sources of remote sensing data. The best-received images, photos, and data need
skilled and experienced experts with extensive information and knowledge of ground cover.
2. In designing a remote sensing system,
the following data collection parameters shall be considered for selection of
the sensors and the equipment carrying these sensors:
- Data collection scale
- Image zoom
- Frame time
sensing maps and images
Aerial photography as the basis for mapping projects is now being used by international mapping agencies. These photos and images play an important role in natural hazard risk mitigation. Aerial photography is usually used for quick response monitoring of a natural disaster or for following the inputs needed for updating maps for quick response in an emergency. Aerial imagery provides high-resolution photographs, 10 to 30cm, with higher quality compared to high-resolution satellite imagery.
The flight of a flying object like UAV can be scheduled quickly compared to satellites. In airborne remote sensing, in addition to traditional methods, aerial photography via manned aircraft, innovative methods including UAVs are used for real-time/on-line/ imagery, live video, and remote sensing.
Corporations, platforms, and system capabilities, as well as general and specific applications of these flying objects, are now extensively developed. The advent of small, accessible unmanned aerial vehicles and advances in automated mapping have run the way for forming new capabilities for various human activities.
Table 2 presents different types of these unmanned aerial vehicles used for hazard assessment and their risk mitigation. It should be noted that fixed-wing UAV has higher flight continuity and can collect image data for larger areas while quadcopters and Hexa-Rotors have greater maneuverability for smaller areas. They are used for rapid data collection and rapid imagery, 5 – 20 cm, in small areas, few square kilometers, due to easy employment and preparation.
Nowadays, these flying UAVs are used in various countries especially by mapping agencies due to their accurate and automatic navigation and automated imagery and mapping. Small UAVs have higher speed and agility and can meet the needs of mapping teams at a lower cost compared to manned flyers. They can also be used for data collection in inaccessible areas since they can be programmed for automated flights at different flight paths. Hence, these small UAVs are very useful for hazard assessment and risk mitigation. They can provide internet and cell phone access for emergency services and customers.
Nowadays, researchers and related organizations have taken extensive practical and empirical measures for remote sensing and assessment of natural phenomena and their risk mitigation via small UAVs. The volume of papers published in this field, especially since 2017 confirms this claim. Table 3 presents some of the papers and measures are taken in this field.
Table 2. Different types of these UAVs used for natural
phenomena hazard assessment and risk mitigation
Title of the performed
|Yao Yao, Shanlin Weia,||Application of UAV In Monitoring Chemical Pollutant Gases||
Chemical Engineering Transactions,
Vol. 67, 2018
|Tien-Yin Chou.Mei-Ling Yeh, Ying-Chih Chen, Yen-Hung Chen||
Disaster Monitoring and Management
by the Unmanned Aerial Vehicle
100 Years Isprs, Vienna, Austria, July 5–7, 2010, Papers, Vol.
Xxxviii, Part 7b
|Haifeng Huang, Jingjing Long,||
A Method for Using Unmanned Aerial Vehicles for Emergency Investigation
of Single Geo-Hazards And Sample Applications
Of This Method
|Nat. Hazards Earth Syst. Sci., 17, 1961–1979, 2017|
|Óscar Alvear, Nicola Roberto Zema,||
Using UAV-Based Systems to Monitor Air Pollution in Areas With Poor
Journal Of Advanced Transportation, Hindawi Publishing Corporation, 2017,
|Tamás Fráter1, Tatjána Juzsakova2,||
Unmanned Aerial Vehicles in Environmental
Monitoring—An Efficient Way for Remote Sensing
|Journal Of Environmental Science And Engineering A 4 (2015) 85-91|
UAV- Based Photogrammetry and
Geo-computing for Hazards and Disaster
Risk Monitoring – A Review
Stuart M. Adams And Carol J.
A Survey Of Unmanned Aerial
Vehicle (UAV) Usage For Imagery Collection in Disaster Research and
|F. Malandrino, C.-F. Chiasserini, C.||Planning UAV Activities for Efficient User Coverage in Disaster Areas||ArXiv: 1811.12450v3|
|Daniele Giordan, Yuichi Hayakawa,||Application Of Drone Technology in Post-Disaster Recovery In India||
International Journal Of Recent Scientific Research
Vol. 8, Issue, 5, Pp. 17068-17069, May 2017
|Daniele Giordan, Yuichi Hayakawa, Francesco Nex||
Review Article: The Use Of Remotely Piloted Aircraft Systems (Repass) For
Natural Hazards Monitoring and Management
|Nat. Hazards Earth Syst. Sci., 18, 1079–1096, 2018|
|Mohamed Aboubakr, Ahmed Balkis||Environmental Monitoring System by Using Unmanned Aerial Vehicle||Network Protocols And Algorithms Issn. 1943-3581 2017, Vol. 9, No. 3-4|
|Daniel Hein_, Steven Bayer,||An Integrated Rapid Mapping System for Disaster Management||
Volume Xlii-1/W1, 2017
Isprs Hannover Workshop: Hrigi. 17 – Cmrt 17 – Isa 17 – Eurocow 17, 6–9
June 2017, Hannover, Germany
|Milan Erdelj, Enrico Natalizio||UAV-Assisted Disaster Management: Applications and Open Issues||International Conference On Computing, Networking, And Communications (Icnc 2016), Feb 2016, Kauai, United States.|
|Daniele Ventura, Andrea Bonifazi,||
Unmanned Aerial Systems (UAS) For Environmental
Monitoring: A Review With Applications in Coastal Habitats(Chapter -Book)
Volume Xlii-1/W1, Isprs Hannover Workshop: Hrigi. 17 – Cmrt 17 – Isa 17 –
Eurocow 17, 6–9, Germany
Table 3. Some of the papers on using UAVs for remote sensing of natural phenomena
Airborne Data collection technologies
Airborne remote sensing is the process of recording data such as images and photographs from the sensors mounted on various UAVs such as drones and aircraft. Existing aerial systems include aerial cameras with the primary maps and high-resolution images, Multispectral sensors, Near IR, red, and green band (NDVI), thermal infrared scanners for Detection and measurement of temperature changes, passive microwave imaging radiometers and side-looking airborne radars (SLAR).
Systems that provide the most amount of practical and useful data for designing an integrated plan for hazard assessment include Aerial cameras, multispectral scanners, thermal infrared scanners, and side-looking airborne radars. The availability of airborne remote sensing imagery varies depending on the type of required data.
However, due to specific applications, imagery is running in many areas of the world, not including military areas. The acquisition of infrared, IR, and radar data is more complex than aerial photography. Obviously, for a large area, radar may be less expensive than photography. Due to the specialized systems and operators required to produce IR and SLAR imagery, such data are usually available only for a limited number of organizations.
Otherwise, the cost of aircraft or drones, their equipment and crews may be high in airborne methods but will be accepted if it provides the required amount of data per area for full an area coverage. In addition, it should be noted that each sensor has an optimal time during the day, season, or an individual application table to present its best performance. In general, various technologies used for aerial applications can be categorized into the following three categories:
and Information fusion technology
Finally, it can be said that an information fusion model and it’s software and hardware, in the case of heterogeneous data from dissimilar sensors, is the heart of a multi-sensor system. It is a novel technology that could be applied to achieve the mentioned goals.
Thus data and information fusion technology is the most important tool that can be used in remote sensing systems for wildfires hazard assessment and prevention. Each of the multiple sensors has its own strengths and weaknesses. Using a proper data fusion model such as shown in figure 1, the heterogeneous data will be combined at the different levels and the results will be more valuable information compared to the algebraic sum of the singular sensor’s capacities and lead to the best decision-making and also the best action.
Figure 1. A combination model of data
- An integrated system for forest fire assessment and prevention includes processes of the collection of dissimilar data, categorizing, assignment, and processing of data, decision-making, and action.
- The development of this kind of system with a varying environment, a large number of subsystems, and complicated requirements is a large and complex project.
- Given that the subsystems of this system are capable of operating as an individual system, this project can be called the development of a system of systems.
- Due to the multidisciplinary or multi-professional nature of a system of systems project, balanced, coordinated and integrated development of systems and subsystems would be impossible without careful and actual implementation of systems engineering (SE) processes.
| José Aguilar-Manjarrez and al., Guidance on spatial technologies for disaster risk management in aquaculture, FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS Rome, 2018.|
A technical report, Primer on Natural Hazard Management in
Integrated Regional Development Planning, Department of Regional Development and
Environment Executive Secretariat for Economic and Social Affairs
Organization of American States With support from the Office of Foreign
Disaster Assistance United States Agency for International Development, Washington, D.C. 1991
Lillesand, T.M., Kiefer, R.W. and Chipman, J.W., Remote Sensing and Image Interpretation, 7th
Edition, 6th Edition, John Wiley & Sons, 2007.
Yao Yao, Shanlin Weia, Application of UAV In Monitoring Chemical Pollutant
Gases, Chemical Engineering Transactions, Vol. 67, 2018.
| Travaglia C, Kapetsky JM, Profeti C. Inventory and monitoring of shrimp farms in Sri Lanka by ERS SAR data, FAO working paper, Vol. 1. Rome: Food and Agriculture Organization of the UN; 1999.|
Tien-Yin Chou.Mei-Ling Yeh, Ying-Chih Chen, Yen-Hung Chen, Disaster
Monitoring and Management by the
Unmanned Aerial Vehicle Technology, 100 Years Isprs, Vienna, Austria,
July 5–7, Papers, Vol. Xxxviii, Part 7b, 2010.
Haifeng Huang, Jingjing Long, A Method for Using Unmanned Aerial Vehicles for
Emergency Investigation of Single Geo-Hazards And Sample Applications of This
Method, Nat. Hazards Earth Syst. Sci., 17, 1961–1979, 2017.
Óscar Alvear, Nicola Roberto Zema, Using UAV-Based Systems to Monitor Air
Pollution in Areas with Poor Accessibility, Journal of Advanced
Transportation, Hindawi Publishing Corporation, Pp.1-14, 2017.
Tamás Fráter, Tatjána Juzsakova, Unmanned Aerial Vehicles in Environmental
Monitoring—An Efficient Way for Remote Sensing, Journal Of Environmental
Science And Engineering A 4, 85-91, 2015.
| Christopher Gomez, UAV- Based Photogrammetry and Geo-computing for Hazards and Disaster Risk Monitoring – A Review, 2016.|
Stuart M. Adams and Carol J. Friedland, a Survey of Unmanned Aerial Vehicle
(UAV) Usage for Imagery Collection in Disaster Research and Management, 2011.
F. Malandrino, C.-F. Chiasserini, C, Planning UAV Activities for Efficient
User Coverage in Disaster Areas, arXiv: 1811.12450v3, 2019.
Daniele Giordan, Yuichi Hayakawa, Application Of Drone Technology in
Post-Disaster Recovery In India, International Journal Of Recent Scientific
Research, Vol. 8, Issue, 5, Pp. 17068-17069, May 2017.
| Daniele Giordan, Yuichi Hayakawa, Francesco Nex, Fabio Remondino, and Paolo Tarolli, Review article: the use of remotely piloted aircraft systems (RPASs) for natural hazards monitoring and management, Nat. Hazards Earth Syst. Sci., 18, 1079–1096, 2018.|
Mohamed Aboubakr, Ahmed Balkis, Environmental Monitoring System by Using
Unmanned Aerial Vehicle, Network Protocols And Algorithms Issn. 1943-3581,
Vol. 9, No. 3-4, 2017.
| Daniel Hein, Steven Bayer, an Integrated Rapid Mapping System for Disaster Management, Volume Xlii-1/W1, Isprs Hannover Workshop: Hrigi. 17 – Cmrt. 17 – Isa 17 – Eurocow 17, 6–9, Hannover, Germany, June 2017.|
Light Detection and Ranging