The total solar eclipse on July 2, 2019, has been studied by using data of the La Serena ground magnetic station in Chile located in the path of the totality (at geographic coordinates: 29.827° S, 71.261° W). The event reached 100% darkness and occurred from 1522:34 hr to 1746:36 hr LT. We monitored the X, Y, Z‑components of the geomagnetic field with a fluxgate magnetometer to investigate their variation caused by the passing of the Moon in front of the Sun. Our results show positive growth up to ∼12 nT for all components in the same time window during the eclipse and in total synchrony with its phases. Having to discard any effect on the observations such as magnetic and solar activities, seasonal and geographical conditions, and instrumental effects, we report a total increase of the geomagnetic field during this phenomenon.

The first report on the changes in meteorological parameters during the total solar eclipse of July 2, 2019, in La Serena (Chile), is presented. The event could be observed from morning time on the east of New Zealand, in the South Pacific Ocean, to sunset time in Chile. Several meteorological properties such as global radiation Rg, net radiation Rn, reflected radiation Rr (in Wm–2/min), air temperature (TA in °C), relative humidity (RH in %), wind speed amplitude (WS in ms–1), and wind speed direction (WD in degrees), were recorded with La Serena weather station SER (29.827°S, 71.261°W, 28 masl) at 1‑minute time resolution. Importantly, SER was located at 40 km from the axis of the umbra that covered 201 km of width, where it reached 100% darkness at a magnitude of 1.009 during a clear-sky day. Under these auspicious conditions, we observed a rate of changes in the drop of the radiation components of 3.1, 2.4, and 0.5 (Wm–2/min) for Rg, Rn, and Rr, respectively, with a 100% reduction in the components of surface solar radiation (0 Wm–2) during totality. In addition, all components showed a ~34% energy loss during the eclipse in comparison with the day before the event. Also, the rate of changes of –3.3 °C in TA, +11% in RH, –1.11 ms–1 in WS, and 180° to 340° for WD in total synchrony with the passing of the moon in front of the sun, reaching respective peaks at ~5 min lag with respect to totality. Thus, our results show a progressive change in all meteorological parameters in total synchrony with the eclipse’s phases caused by the passing of the moon in front of the sun.

Mathai’s pathway model is playing an increasingly prominent role in statistical distributions. As a generalization of a great variety of distributions, the pathway model allows the studying of several non-linear dynamics of complex systems. Here, we construct a model, called the Pareto–Mathai distribution, using the fact that the earthquakes’ magnitudes of full catalogues are well-modeled by a Mathai distribution. The Pareto–Mathai distribution is used to study artificially induced microseisms in the mining industry. The fitting of a distribution for entire range of magnitudes allow us to calculate the completeness magnitude ($M_c$). Mathematical properties of the new distribution are studied. In addition, applying this model to data recorded at a Chilean mine, the magnitude $M_c$ is estimated for several mine sectors and also the entire mine.

The cancellation factor (CF) is a model for the ratio between gravity wave perturbations in the nightglow intensity to those in the ambient temperature. The CF model allows us to estimate the momentum and energy flux of gravity waves seen in nightglow images, as well as the divergence of these fluxes due to waves propagating through the mesosphere and lower thermosphere region, where the nightglow and the Na layers are located. This study uses a set of wind/temperature Na lidar data and zenith nightglow image observations of the $OH$ and $O{(}^{1}S)$ emissions to test and validate the CF model from the experimental perspective. The dataset analyzed was obtained during campaigns carried out at the Andes Lidar Observatory (ALO), Chile, in 2015, 2016, and 2017. The modeled CF was compared with observed CF values calculated using the ratio of wave amplitude in nightglow images to that seen in lidar temperatures for vertically propagating waves. We show that, in general, the modeled CF underestimates the observed CF results. However, the $O{(}^{1}S)$ emission line has better agreement with respect to the modeled value due to its supposedly simpler nightglow photochemistry. In contrast, the observed CF for the $OH$ emission deviates by a factor of two from the modeled CF asymptotic value.