Other Earth Sciences Commons^™

Monitoring Air Fluxes In Caves Using Digital Flow Metres, Claudio Pastore, Amir Sedaghatkish, Eric Weber, Nicolas Schmid, Pierre-Yves Jeannin, Marc Luetscher

International Journal of Speleology

Precise measurements of airflow within caves are increasingly demanded to assess heat and mass transfers and their impacts on the karst environment, including subsurface ecosystems, hydrochemistry of karst water and secondary mineral precipitates. In this study, we introduce a new, low-cost and lightweight device adapted to monitoring air fluxes in caves which addresses the need for reliable measurements, low power consumption, durability and affordability. The device was calibrated in a wind tunnel, showing the high accuracy and precision of the device. Field-related uncertainties were further investigated in a ventilated cave to determine the effect of local airflow conditions on the …

Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman

Numeracy

Timothy H. Dixon. 2017. Curbing Catastrophe: Natural Hazards and Risk Reduction in the Modern World. (New York, NY: Cambridge University Press) 300 pp. ISBN 978-1108113663.

In Curbing Catastrophe, Timothy H. Dixon explores commonalities among natural disasters like Hurricane Katrina, the 2010 earthquake in Haiti, and the meltdown at Fukushima. He identifies communication failure between scientists and policy makers as a major culprit in the devastation that results from such events and offers strategies for improving that communication. He includes optional in-depth scientific and quantitative examinations of the events and the resulting devastation, making the book appropriate for use …

Toxicity Of Fluorescent Tracers And Their Degradation Byproducts, Philippe Gombert, Hugues Biaudet, René De Sèze, Pascal Pandard, Jean Carré

International Journal of Speleology

Tracer tests are frequently used to delineate catchment area of water supply springs in karstic zones. In the karstic chalk of Normandy, the main tracers used are fluorescent: uranine, sulforhodamine B, naphtionate, and Tinopal®. In this area, a statistical analysis shows that less than half of the injected tracers joins the monitored restitution points and enters the drinking water system where they undergo chlorination. Most of the injected tracers is absorbed in the rock matrix or is thrown out of the aquifer via karstic springs: then it can join superficial waters where it is degraded due to the sun and …

The Relationship Between Carbon Dioxide Concentration And Visitor Numbers In The Homothermic Zone Of The Balcarka Cave (Moravian Karst) During A Period Of Limited Ventilation, Marek Lang, Jiří Faimon, Camille Ek

International Journal of Speleology

The evolution of CO₂ levels with and without human presence was studied in a selected site (Gallery Chamber) of the homothermic zone of the Balcarka Cave (Moravian Karst, Czech Republic) during the fall, a period of limited ventilation. There were recognized various factors controlling the cave CO₂ levels under different conditions in the exterior and interior. When visitors were absent, CO₂ levels were controlled by the advective CO₂ fluxes linked to cave airflows and reaching up to ~1.5x10^-3 mol s^-1. These fluxes exceed by orders of magnitude the exchanged diffusive fluxes (up to …

Cave Ventilation Is Influenced By Variations In The Co2-Dependent Virtual Temperature, Enrique P. Sánchez-Cañete, Penélope Serrano-Ortiz, Francisco Domingo, Andrew S. Kowalski

International Journal of Speleology

Dynamics and drivers of ventilation in caves are of growing interest for different fields of science. Accumulated CO₂ in caves can be exchanged with the atmosphere, modifying the internal CO₂ content, affecting stalagmite growth rates, deteriorating rupestrian paintings or creating new minerals. Current estimates of cave ventilation neglect the role of high CO₂ concentrations in determining air density – approximated via the virtual temperature (T_v) –, affecting buoyancy and therefore the release or storage of CO₂. Here we try to improve knowledge and understanding of cave ventilation through the use of T …

Cora – A Dedicated Device For Carbon Dioxide Monitoring In Cave Environments, Marc Luetscher, Felix Ziegler

International Journal of Speleology

High resolution time-series of cave CO₂ fluctuations are increasingly demanded to quantify calcite precipitation processes. CORA, an energy-efficient NDIR-device, has been specifically developed for the long-term monitoring of carbon dioxide in remote cave environments. To allow comparison between different cave sites, changes in air pressure and temperature are compensated for using dedicated probes. Laboratory experiments demonstrate that CORA’s precision is adapted to the analysis of spatially and temporally variable CO₂ regimes and therefore suitable for a large number of applications. Data obtained with 12 independently calibrated instruments are reproducible within 3% (1σ). The two-point calibration function is validated …

Spatially Dense Drip Hydrological Monitoring And Infiltration Behaviour At The Wellington Caves, South East Australia, Catherine N. Jex, Gregoire Mariethoz, Andy Baker, Peter Graham, Martin S. Andersen, Ian Acworth, Nerilee Edwards, Cecilia Azcurra

International Journal of Speleology

Despite the fact that karst regions are recognised as significant groundwater resources, the nature of groundwater flow paths in the unsaturated zone of such fractured rock is at present poorly understood. Many traditional methods for constraining groundwater flow regimes in karst aquifers are focussed on the faster drainage components and are unable to inform on the smaller fracture or matrix-flow components of the system. Caves however, offer a natural inception point to observe both the long term storage and the preferential movement of water through the unsaturated zone of such fractured carbonate rock by monitoring of drip rates of stalactites, …