Intensive Urbanization, Urban Meteorology and Air Pollutants: Effects on the Temperature of a City in a Basin Geography

Abstract

A qualitative study of thermal transfers is carried out from a record of measurements (time series) of meteorological variables (temperature, relative humidity and magnitude of wind speeds) and pollutants (PM10, PM2.5 and CO) in six localities located at different heights in the geographic basin of Santiago de Chile. The measurements were made in two periods, 2010–2013 and 2017–2020 (a total of 2,049,336 data), the last period coinciding with a process of intense urbanization, especially high-rise construction. The measurements, in the form of hourly time series, are analyzed on the one hand according to the theory of thermal conduction discretizing the differential equation of the temporal variation in the temperature and, on the other hand, through the theory of chaos that provides the entropies (S). Both procedures demonstrate, comparatively, that the last period of intense urbanization presents an increase in thermal transfers and temperature, which affects urban meteorology and makes it more complex. As shown by the chaotic analysis, there is a faster loss of information for the period 2017–2020. The consequences of the increase in temperature on human health and learning processes are studied.

Urban Meteorology, Pollutants, Geomorphology, Fractality, and Anomalous Diffusion

“…After calculating the chaotic parameters according to the procedure indicated in Appendix C and collecting the values of C K = S K, MET. VAR ./S K, POLLUT , according to Table A1 of Appendix D [43,54,55,99], which incorporates six new localities, the quotient between the sum of the entropies of contaminants and that of the meteorological variables, by geographical morphologies, is presented in Table 3. When graphing C K , in Figure 7, according to the urban settlements in the three geographical morphologies of this study-basin, mountain, and coast-these were numbered by ( 1), (2) .…”

“…and meteorological variables (T, RH, WS, etc.) [4,[50][51][52][53][54][55][56][57][58]. The application of chaos theory to an atmospheric system depends on phase space reconstruction theory [4].…”

“…The definition of metric entropy is due to Shannon [53], and, later on, it was applied to dynamical systems. Kolmogorov [54] and Sinai [55] proved that it is a topological invariant (K-S entropy) [56][57][58].…”

“…With C K one can study the boundary layer and the disturbances that affect it [54], showing the following: sensitivity to turbulence near the ground; who exerts a greater influence between urban meteorology and pollutants by calculating the Kolmogorov entropy for each variable; the asymptotic decay of turbulence with height, consistent with a Kolmogorov cascade-like behavior; in three dimensions, the areas of the highest C K density, the interactive phenomenon of urban meteorology-pollutants and entropic forces; the evolution of C K over time by measurement periods; the existence of thermal effects in the form of flows; sensitivity to events (pandemic, urban densification, heat waves, thermal islands, fires, etc. ); its behavior in three geographies, i.e., basin, coast, and mountain range; the presence of resilience and sustainability according to the initial conditions of the study area; and how entropic flows and vertical wind speeds favor polluting "contagion" between cities, to the detriment of urban meteorology.…”

The Effects of Lockdown, Urban Meteorology, Pollutants, and Anomalous Diffusion on the SARS-CoV-2 Pandemic in Santiago de Chile

“…A geographical basin corresponds to an area surrounded by mountains that make it difficult to ventilate and expose it, in times of climate change, to extended periods of drought and an increase in temperature [1]. Urban densification also contributes to this, especially with high-rise buildings [1,2]. These same conditions can contribute to the persistence of diseases with varied characteristics that affect the population [3,4].…”