Pyroclastic Flows and Related Disasters

In situ production of ash in pyroclastic flows

[1] Abrasion and comminution of pumice clasts during the propagation of pyroclastic flows have long been recognized as a potential source for the enhanced production of volcanic ash, however, their relative importance has eluded quantification. The amount of ash produced in situ can potentially affect runout distance, deposit sorting, the volume of ash introduced in the upper atmosphere, and in...

Slow-moving and far-travelled dense pyroclastic flows during the Peach Spring super-eruption

Explosive volcanic super-eruptions of several hundred cubic kilometres or more generate long run-out pyroclastic density currents the dynamics of which are poorly understood and controversial. Deposits of one such event in the southwestern USA, the 18.8 Ma Peach Spring Tuff, were formed by pyroclastic flows that travelled >170 km from the eruptive centre and entrained blocks up to ∼ 70-90 cm di...

Global Increase in Climate-Related Disasters

Intense climate-related disasters—floods, storms, droughts, and heat waves—have been on the rise worldwide. At the same time and coupled with an increasing concentration of greenhouse gases in the atmosphere, temperatures, on average, have been rising, and are becoming more variable and more extreme. Rainfall has also been more variable and more extreme. Is there an ominous link between the glo...

Periodically correlated and multivariate symmetric stable‎ ‎processes related to periodic and cyclic flows

‎In this work we introduce and study discrete time periodically correlated stable‎ ‎processes and multivariate stationary stable processes related to periodic and cyclic‎ ‎flows‎. ‎Our study involves producing a spectral representation and a‎ ‎spectral identification for such processes‎. ‎We show that the third‎ ‎component of a periodically correlated stable process has a component related to a...

Public Health Perspectives Related to Technological Disasters and Terrorism