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Reinaldo Haas

Publications and source records attributed to Reinaldo Haas.

2 recordsLinked to original sources

Toroh: An Extreme Orographic Convective Event Physical Modelling and Implications for Persistent Geological Anomalies

We introduce the toroh -- formally designated an Extreme Orographic Convective Event (EOCE) -- as a previously uncharacterised class of atmospheric hazard distinct from downbursts and conventional hailstorms. The toroh is a coherent hydraulic ice-piston formed when a convective system with anomalously narrow drop size distribution (mu ~ 20) undergoes explosive secondary ice production via the Hallett-Mossop mechanism, triggered by marine iodine ice-nucleating particles injected by a vortex or orographic resonance with an inselberg (Planalto Mirador, SC, Brazil). The piston collapses coherently into canyon terrain, producing a two-phase acoustic signature, seismic tremor M_L ~ 2-3, and a diagnostic erosion scar with zero fine-grained matrix. Piston cohesion is justified by ice sintering kinetics: tau_p ~ 0.04 s << tau_sint = 1-10 s, and sintered tensile strength ~10^4 Pa exceeds aerodynamic fragmentation pressure ~10^3 Pa. We propose EOCE as a candidate mechanism for four persistent geological anomalies: (1) erosional amphitheatres in resistant bedrock; (2) heavy mineral concentration in canyon lag deposits; (3) spatiotemporal heterogeneity of the Great Unconformity, incompatible with uniform Snowball Earth glaciation; (4) the nutrient pulse preceding the Cambrian Explosion. In pristine pre-industrial conditions, EOCE frequency is estimated at 1-10 per century per canyon -- sufficient for independent geomythological encoding in ~18 culturally isolated traditions. The Adams Event (Laschamp, ~42 ka) amplified this baseline 10-100x; 20th-century tetraethyl-lead aerosols suppressed it below observational threshold. A 3D anelastic bin-microphysics model and testable predictions are presented. Code: https://github.com/reinaldohaas/toro-model

physics.geo-ph

Logarithmic Wind Profile: A Stability Wind Shear Term

A stability wind shear term of logarithmic wind profile based on the terms of turbulent kinetic energy equation is proposed. The fraction influenced by thermal stratification is considered in the shear production term. This thermally affected shear is compared with buoyant term resulting in a stability wind shear term. It is also considered Reynolds stress as a sum of two components associated with wind shear from mechanical and thermal stratification process. The stability wind shear is responsible to Reynolds stress of thermal stratification term, and also to Reynolds stress of mechanical term at no neutral condition. The wind profile and its derivative are validated with data from Pedra do Sal experiment in a flat terrain and 300m from shoreline located in northeast coast of Brazil. It is close to the Equator line, so the meteorological condition are strongly influenced by trade winds and sea breeze. The site has one 100m tower with five instrumented levels, one 3D sonic anemometer, and a medium-range wind lidar profiler up 500m. The dataset are processed and filter from September to November of 2013 which results in about 550 hours of data available. The results show the derivative of wind profile with R^2 of 0.87 and RMSE of 0.08 m/s. The calculated wind profile performances well up to 400m at unstable condition and up to 280m at stable condition with R^2 better than 0.89. The proposed equation is valid for this specific site and is limited to a stead state condition with constant turbulent fluxes in the surface layer.

physics.ao-ph