# A Component-Based Approach to Early Warning Systems: A Theoretical Model
## 2 Materials and Methods  
As part of this research, a definition of EWSs has been established. The definition is based on the studied materials in this article and the authors' expertise gained through years of academic research in disaster management. Early warning systems are classified into three defined components based on the timeline of a hazard's development and the need for information distribution. The general classification of risk components, as defined by UNDRR [9], consists of four elements. However, this model focuses on three components, prioritising the technological aspects and timeline factors crucial for effective EWSs. Each component is distinct in terms of the data collected and requires specific actions to facilitate warnings and alerts for the population. The classification into components stems from the data requirements and the types of data assessed at a given time. Additionally,the format and level of data distribution to at-risk populations are also considered. To formulate these components, we conducted a comprehensive review of relevant data and information, incorporating key factors into each component's description. This process involved analysing:  
* Technology for data collection;
* Timeline and probability of occurrence;
* Information distribution requirements;
* Relevant measures and restrictions. The next section of this paper focuses on selected natural hazards, primarily those that are currently the most devastating in terms of economic damage and loss of life [9]. However, not all such events have been included in this study. In the case of storms and cyclones, the key associated phenomena are wind and heavy rainfall, which often lead to flooding. Additionally, cyclones align with the definition of storms [38; 39]. Given these common characteristics, the same types of sensors would be used for monitoring flooding and wind-related parameters. Based on an analysis of correlations between different natural hazards, as well as a review of their impacts and characteristics, this paper focuses only on selected natural hazards:  
* Floods;
* Droughs;
* Extreme temperature;
* Wildfires;
* Wind;
* Landslides;
* Earthquakes. For the purposes of EWSs, the primary causes of selected natural hazards were identified. The criteria for primary causes were that they must be measurable by sensors and critical for the event's occurrence (i.e., if the primary cause does not occur, the crisis event cannot take place). In addition, secondary causes were also defined. A secondary cause is one that is not essential for the crisis event to occur, but it significantly influences its intensity or extent. The criteria for measurability by sensors was applied also. The identification of primary and secondary causes and manifestations involved a thorough examination of relevant literature from the Scopus database. Sources were selected based on their focus on the specific natural hazard under consideration and their detailed description of its causes. Although a systematic approach was not employed in formulating the causes, each cause is supported by at least two independent sources. The final selection and definition of the causes were further refined through expert judgment and in-depth discussions among the authors. From the perspective of public warnings, the manifestation of the crisis event is the most crucial aspect. These manifestations reflect the negative impacts of the natural hazards, posing threats to human life, property, and the environment. Their effects result in financial losses as well as fatalities. The primary causes, secondary causes, and manifestations of natural hazards were categorised into groups based on the type of parameters influencing them. These groups play a key role in understanding the origins of crisis events, providing a structured approach to categorising dominant influencing factors. The methodology for forming these groups is outlined in Table 1.  
However, for each natural hazard, there are numerous primary causes that influence its occurrence.