Ponente
Descripción
The report published by the European Union's Copernicus Climate Change Service states that 2025 was the third warmest year on record, marking the first time that the global average temperature over a period of three consecutive years exceeded the 1,5 °C limit. With the increase in the planet's average temperature, extreme weather events are becoming more and more frequent, including heat waves. The World Meteorological Organization (WMO) defines this phenomenon as a period of at least five consecutive days during which the daily maximum temperature exceeds the daily average temperature by 5 °C. According to the National Center for Monitoring and Alerts of Natural Disasters (Cemaden/Brasil), Brasil recorded seven heat waves that year. Therefore, this work aimed to study the displacement and propagation of a heat wave using mathematical modeling via the partial differential equation of advection-diffusion; to understand the Lax-Friedrichs numerical method according to (Leveque, R.J., Finite Volume Methods for Hyperbolic Problems, Cambridge, 2002) and to simulate scenarios that portray heat waves. In this case, the advective term in the equation represents the displacement of a mass of hot, dry air, the diffusive term characterizes the spreading of heat along the domain, and the function $u(x,y,t)$ depicts how the average temperature changes at a point in the domain, at a given instant, with the passage of the air mass. For discretization, the Lax-Friedrichs method was used, and the computational implementations were performed in Python, assuming null von Neumann boundary conditions and parameters that respect the Courant-Friedrichs-Lewy (CFL) stability condition. In the examples developed, the velocity field vectors were defined so that the air mass moved from west to east and from southwest to northeast, at a low speed. These directions were chosen taking into account the characteristics of the climatic phenomenon, as described in different literature, such as (Reis, N. et al., Atmos. 10(5), 248, 2019) and (Sanders R.A., AMS. 81, 67-73, 1953). Scenario simulations showed the passage of a mass of hot, dry air over a region, causing temperatures to rise to heat wave levels. Finally, it is important to highlight the relevance of research involving the application of mathematics to real world problems, such as climate issues, as it helps in reaching conclusions and making decisions. This impacts people's health, flora, fauna, and especially the survival of individuals who are in a situation of social and environmental vulnerability.