# A Component-Based Approach to Early Warning Systems: A Theoretical Model
## 3 Results  
### Components of Early Warning Systems  
EWSs currently have a wide range of applications. They are used to warn against crisis events of various types. Since crisis management is a multidisciplinary field, such \begin{table}
\begin{tabular}{c c} \hline
**Disaster Group** & **Definition** \\ \hline Geophysical & Events originating from solid earth \\ \hline Meteorological & Events caused by short-lived/small to meso-scale \\  & atmospheric processes (in the spectrum from \\  & minutes to days) \\ \hline Hydrological & Events caused by deviations in the normal water cycle \\  & and/or overflow of bodies of water caused by wind set-up \\ \hline Climatological & Events caused by long-lived/meso- to macro-scale \\  & processes (in the spectrum from intraseasonal to \\  & multi-decadal climate variability) \\ \hline \end{tabular}
\end{table} 
Table 1: Category classification of natural causes [40]. systems require knowledge from various disciplines, which should be integrated into the general crisis management framework, under which the need for EWSs also falls. As [PERSON] et al. [22] mentioned, EWSs rely on a wide sensor network, simulation tools, and decision-making systems. The foundation of every system lies in data collection, which is then analysed and assessed. For natural crisis events, this primarily involves physical parameters, as well as chemical ones, which influence the occurrence of natural hazard. The infrastructure of EWSs relies on data collection using sensors or satellite technologies. The systems consist of numerous parts, and various technological devices and often people are integrated into them. An EWS could be defined as a complex system, consisting of data sources, data transmission, data storage, data assessment and evaluation, and the distribution of information about specific impending hazards through technical communication means. The basic difference between EWSs and MHEWSs is the complexity of MHEWSs, which functions for multiple natural hazards; however, the term EWS is also often used in this context. The basic data sources for warning systems are generally sensors. However, in addition to sensors, more complex satellite technologies and satellites should be implemented. The systems should be as comprehensive as possible since their role should not only be to warn about imminent threats in real time, but they should also provide information for early warnings and alerts about the potential development of crisis events. From the perspective of the importance of threat information, EWSs and MHEWSs could be divided into three components based on the timeline in which they operate and the information they distribute:  
* Initial threat component;
* Emerging threat component;
* Imminent threat component. The first component should be the initial threat component. Within this component, the system should record the initial signs of a crisis event, respectively, the potential for its occurrence, the probability of its occurrence, including the likely affected area. These are initial data, which we already acquire today and can work with effectively. These data are used in weather forecasts. This primarily involves the use of forecast models, which mainly stem from satellite images and satellites. These satellites can quantify physical geographic phenomena associated with the movements of the earth's surface (earthquakes, mass movements), water (floods, tsunamis, storms), and fires. These satellites contain different kinds of sensors that are used for the remote sensing of natural hazards over a number of spatial and temporal scales [41]. However, empirical data also play a very important role here, from which the most probable effects of crisis events are modelled [42]. The greatest use of these data sources lies in estimating precipitation, temperature, and wind, which reflect the key characteristics of natural crisis phenomena. They are particularly significant in predicting hurricanes, floods, droughts, extreme temperatures, strong winds, and storms.