GIS and Remote Sensing Applications in Search and Rescue (SAR) Operations

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1 Jessica Worst NRS 509 GIS and Remote Sensing Applications in Search and Rescue (SAR) Operations GIS and remote sensing are now being used in search and rescue operations both in the marine and terrestrial environment. While both environments pose different challenges to search and rescue operations, GIS and remote sensing have revolutionized the process around the world. One of the most important factors in search and rescue is finding the person as fast as possible. GIS systems are being used to quickly evaluate all known data and environmental conditionals so that a probability map can be created. This probability map is then combined with Search Rescue Units (SRUs) capabilities to determine search patterns or search routes to take. The GIS is able to compile many layers of data in a fraction of the time it historically took search teams to compile and evaluate by hand. Additionally, the availability of recent and even real time data enhances search operations that may have been completed with outdated maps of the area in the past. While every GIS is different and they may vary based on terrestrial or marine use, the basic elements are similar. The type of information a GIS can provide to searchers includes digital maps or charts of the area, environmental data, and everything that is known about the current case, whether that is a last know position, cellular phone or radio call, some type of emergency beacon, the planned voyage, or the probable behavior of the person or vessel prior to the incident. All of this data creates different layers indicating probable locations that are then put together into one resultant map (Soylemez and Usul, 2006). This is a Monte Carlo based system in which possible outcomes or locations are generated based on the inputs. These locations are weighted based on the probability that the person would be in that area and search plans are developed to most efficiently and effectively cover the area based on SRU capabilities (Netsch, 2004). The U.S. Coast Guard (USCG), along with other country s Coast Guards and maritime services are employing GIS in search and rescue cases with high success. In 2007, the USCG employed a GIS system (SAROPS) to replace an older search and rescue system with positive results. This system integrates historical and real time environmental data, along with model predictions, from an Environmental Data Server (EDS) while also allowing for manual inputs of winds and currents from on scene units and data from deployed drifters. Other known information about the case, such as a last known position, emergency beacon signals, or intended voyage plan, are entered into the system and SAROPS calculates the most probable locations of the target using this information and an algorithm that predicts drift. The system also includes the capabilities of the SRUs available and develops the best search patterns to cover the search area, which can be coordinated from the response center. These systems have been used effectively by other maritime agencies around the world as well. In 2002, several organizations were participating in a South African Search and Rescue operation when it turned into an actual emergency. Using a GIS called RescueView, the teams where able to identify the last known position of the missing people and track asset movements, which led to successful recovery of the individuals (Pratt, 2002).

2 Terrestrial search and rescue agencies are employing GIS and remote sensing technologies as well. These systems perform similarly in that they also incorporate environmental data with information about the case such as last known position, but they face another challenge, terrain. An area being searched is often unknown to those involved in the search. By using satellite imagery, aerial photography, and elevation models in conjunction with digital topographic maps, terrain and vegetation can be assessed, which is used to help determine search boundaries, size of search areas, and what the probability of detection in an area would be. Unlike maritime operations, the terrain in an area may create physical barriers for rescuers. Search areas on land may not be in regular grid patterns, as maritime and aeronautical operations permit, but instead may be composed of irregular polygons. The satellite imagery and elevation models help to identify and delineate search areas (Ferguson, 2008). Another challenge with terrestrial search and rescue is due to the limited maps available of some regions. Rescuers may be working with outdated maps that do not accurately reflect the terrain, roads, or trails. Again, satellite imagery and digital topographic maps can be compared to ensure the best possible maps are created and used. In addition, rescuers are now often equipped with handheld GPS units which not only assist in identifying search boundaries, but also record the exact location of the search teams. This search team tracking data is uploaded to the GIS and compiled to determine which areas have not received enough coverage, therefore assisting in determining future search routes. This method was used in January 2008 to efficiently search for a man in the San Bernardino Mountains and create subsequent search routes that did not duplicate efforts. GIS was used to determine the search area based on his hike starting location and a 911 call he placed on his cellular phone. Despite the cellular phone signal being lost, rescuers conducted a viewshed analysis to determine possible locations where the call could have been made and incorporated this into determining most probable positions (Patterson, 2008). Viewshed analysis has also been used to identify areas where rescuers may encounter communication difficulties with radios so that communication plans can be worked out ahead of time. Generally speaking, the most useful sources of data for search and rescue operations are last known positions or communications with the person or vessel. Topological maps, elevation models, and satellite imagery are extremely valuable for terrestrial operations. Behavioral profiling can also be useful, which draws on statistical data of previous incidents to determine probable actions of the person. In contrast, maritime operations are severely dependent on environmental factors including currents and winds. Even an exact last known position can be useless without information on where the vessel or person may drift to. Wind and current information is so critical in maritime search operations that GIS products include historical data, model results, and as much real time environmental data as is available for the area, including on scene observations and results from drifters that are deployed in the search area. As GIS and remote sensing are relatively new to search and rescue operations, there are still challenges and areas for possible future improvements. GIS have also been used in SAR efforts following disasters, such as earthquakes, and Fiedrich, Gehbauer, and Rickers (2000) developed a mathematical optimization model to address the challenge of appropriately assigning resources to minimize fatalities during the SAR period following an event. Improvements to these optimization models will create more efficient emergency response procedures after disasters.

3 Improving the availability of real time environmental data and satellite imagery is paramount to agencies focused on search and rescue efforts both on land and water. The USCG performed an analysis of available wind and current data/models in 2008 and recommended inclusion of over 20 new sources to the EDS (Turner, et al., 2008). The increase in availability of this information will provide the GIS system with the best possible data for predicting locations of the person or vessel. For terrestrial operations, improvements in the amount of land mapping data available will be crucial to ensure the most up to date maps are used in search efforts. The more accurate the GIS maps of the terrain are, the easier it will be for rescuers to coordinate search efforts. Although GIS and remote sensing are new to search and rescue efforts within the last few years, they have already proved to be invaluable tools which significantly increase SAR effectiveness. References not included in annotated bibliography: Soylemez, E. and N. Usul. Utility of GIS in search and rescue operations. In: ESRI Users Group Conference, September Available at: Annotated bibliography: Ferguson, D., GIS for wilderness search and rescue. In: Mountaineer Area Rescue Group, ESRI Federal User Conference. Washington, D.C., February This article was about search and rescue principles and how GIS is used to complete a mission in a wilderness environment. The author points out a key difference between terrestrial and maritime or aeronautical SAR is that on land you have manmade and natural barriers that prevent you from using a regular grid pattern for your search area. A case study was examined and the author described how behavioral profiling was taken into account with the GIS because the search was for a severely autistic individual. I found this quite interesting that past statistics of lost individuals could be used to help determine the search area. The author also discusses several areas that greatly assisted search efforts including the ability to easily include updated trail and roadway data with the GIS and the availability of aerial photography. The photography was particularly useful for personnel not familiar with the area and helped searchers to delineate search boundaries based on terrain conditions. Fiedrich, F., R. Gehbauer, U. Rickers, Optimized resource allocation for emergency response after earthquake disasters. Safety Science, 35: This paper addresses SAR efforts following earthquake disasters. These cases are somewhat different because they involve SAR efforts for a large number of people. The authors developed an optimization model that will minimize fatalities following a disaster by efficiently allocating available resources to damaged areas. In this paper, a GIS is not just used as an informational tool, but also aids in decision making by optimizing resources to create the most efficient response to the disaster, as time is the primary factor in survivability. Some parameters included in this model are survival rate for trapped victims, probability of secondary disasters, survival rate of rescued persons without medical treatment, transportation time, and time to complete the work. This article is an excellent example of how a GIS can quickly

4 synthesize various inputs into an optimal plan of action and the benefits provided over traditional emergency response efforts where resource optimization was generally based on the expert knowledge of the rescuers. Netsch, R., The USCG search and rescue optimal planning system (SAROPS) via the commercial/joint mapping tool kit(c/jmtk). In: United States Coast Guard, 24 th Annual ESRI International User Conference August, Available at: This article was written prior to the Coast Guard officially using SAROPS in 2007, but it gives a good example of how a search and rescue case may proceed using SAROPS and the tools it provides. What was particularly interesting in this article was how you can start with only scanty information about a case, but when you put all the layers together on a GIS, the search area can be reduced significantly to a manageable area. The article also discusses the integration of SRU capabilities into the system so the most efficient search patterns can be used to conduct the search. With limited resources at our disposal, it is extremely important for the USCG to maximize resource effectiveness when conducting a search and rescue case. Patterson, T. GIS aids in search for man lost in California s Rugged San Bernardino Mountains. [online] ArcWatch: April Available at: [Accessed 23 November 2010]. This article was unfortunately not a success story. A man went missing in California s San Bernardino mountains when an unexpected blizzard set in and was unfortunately not found until months later. However, his body was located using information that was entered into a GIS to narrow down the search area. The most interesting part of this article was how viewshed was used to map all possible locations his 911 cellular phone call could have been made from before the connection was lost. All search personnel also carried GPS units that recorded their search routes and were downloaded daily and mapped using GIS. This feature proved to be very useful and a new external GPS enabled radio speaker/microphone was also tested which could relay position information for the searches instantaneously and on a timed schedule so you had real time tracking of all your assets in the search. Pratt, M. GIS to the rescue. [online] ArcUser Online: October December Available at: [Accessed 23 November 2010]. This article discusses how a search and rescue exercise in a bay in South Africa turned into an actual search and rescue case when a thick fog quickly rolled in and the volunteer survivors in the water were lost. Because conditions changed so rapidly, the volunteers could not be quickly located and a GIS, RescueView, was used to coordinate search efforts based on a known drop location. The system was also used to track the assets participating in the exercise/actual search operation and the volunteers were located. This system was developed by an individual participating in the exercise and was apparently one of the first GIS search and rescue tools for the marine environment. Other useful elements of this program included a log file that could not be modified. This function was very useful in recording information for debriefing or for legal purposes if searchers needed to testify. This exercise/actual operation was also useful in that it highlighted the importance of changing conditions and the creator was able to modify the program so that updated drift data could be entered based on observations. This is a key feature of the system the USCG uses now as well.

5 Turner, A.C., M.J. Lewandowski, S. Lester, D. Mack, E. Howlett, M. Spaulding, E. Comerma, and M. Wholey (2008). Evaluation of Environmental Information Products for Search and Rescue Optimal Planning System (SAROPS). [online] Available at: < bin/gettrdoc?ad=ada479430&location=u2&doc=gettrdoc.pdf> [Accessed 23 November 2010]. This is a technical report prepared by the Research and Development Center of the USCG in which 212 products from many sources including NOAA, universities, and commercial companies are examined to determine if they should be included in the EDS. The report evaluates each product based on accuracy, availability, and technical support provided by the originator. Over 20 new products are recommended for inclusion into the EDS. The report exhaustively explores new products and is an excellent example of how the USCG is working to improve SAROPS, its current GIS for search and rescue operations. It was very interested to look at the breath of both data and models used for current and wind products, which are crucial to maritime search and rescue efforts. Most of the products the authors recommended for inclusion into the EDS were developed by NOAA and universities around the country.