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The use of rogation ceremony records in climatic reconstruction: a case study from Catalonia (Spain)
The use of rogation ceremonies due to environmental causes constitutes an important source of information in paleoclimatic reconstructions. Their specific characteristics and full documental records permit highly reliable series to be reconstructed with daily, monthly, seasonal or annual resolution over periods of several centuries (3–4 centuries in the case of Catalonia). The levels of intensity, reflected in the type of religious ceremony enacted, allows quantification. Comparative analysis is made possible by the similarity of the mechanisms developed in different localities. The use of these series in paleoclimatological studies is a promising line of research, particularly as regards the pro pluvia rogations celebrated in the Mediterranean countries and in South America. 相似文献
3.
Mariano Barriendos Javier Martín-Vide Juan Carlos Peña Roberto Rodríguez 《Climatic change》2002,53(1-3):151-170
Meteorological observations in the city of Cádiz are acknowledged as having been made from the middle of the 18th century onwards although they were only recorded and preserved in documentary form from 1789 onwards. Data readings were taken at the new Naval Observatory in San Fernando, ten kilometres from Cádiz, from 1797 onwards. Continuous series for temperature and atmospheric pressure at a daily resolution have been compiled and constructed from 1817 until 1996. The data series is composed of thrice daily observations made at Cádiz (1821–1880) by local observers and hourly data from Naval Observatory at San Fernando (1870–1996). 相似文献
4.
A. Aiuppa S. Inguaggiato M. O’Dwyer M.J. Padgett M. Valenza 《Geochimica et cosmochimica acta》2005,69(7):1861-1871
We present here new measurements of sulfur dioxide and hydrogen sulfide emissions from Vulcano, Etna, and Stromboli (Italy), made by direct sampling at vents and by filter pack and ultraviolet spectroscopy in downwind plumes. Measurements at the F0 and FA fumaroles on Vulcano yielded SO2/H2S molar ratios of ≈0.38 and ≈1.4, respectively, from which we estimate an H2S flux of 6 to 9 t · d−1 for the summit crater. For Mt. Etna and Stromboli, we found SO2/H2S molar ratios of ≈20 and ≈15, respectively, which combined with SO2 flux measurements, suggest H2S emission rates of 50 to 113 t · d−1 and 4 to 8 t · d−1, respectively. We observe that “source” and plume SO2/H2S ratios at Vulcano are similar, suggesting that hydrogen sulfide is essentially inert on timescales of seconds to minutes. This finding has important implications for estimates of volcanic total sulfur budget at volcanoes since most existing measurements do not account for H2S emission. 相似文献
5.
The regional influence of the Madden–Julian oscillation (MJO) on South America is described. Maps of probability of weekly-averaged rainfall exceeding the upper tercile were computed for all seasons and related statistically with the phase of the MJO as characterized by the Wheeler–Hendon real-time multivariate MJO (RMM) index and with the OLR MJO Index. The accompanying surface air temperature and circulation anomalies were also calculated. The influence of the MJO on regional scales along with their marked seasonal variations was documented. During December–February when the South American monsoon system is active, chances of enhanced rainfall are observed in southeastern South America (SESA) region mainly during RMM phases 3 and 4, accompanied by cold anomalies in the extratropics, while enhanced rainfall in the South Atlantic Convergence Zone (SACZ) region is observed in phases 8 and 1. The SESA (SACZ) signal is characterized by upper-level convergence (divergence) over tropical South America and a cyclonic (anticyclonic) anomaly near the southern tip of the continent. Impacts during March–May are similar, but attenuated in the extratropics. Conversely, in June–November, reduced rainfall and cold anomalies are observed near the coast of the SACZ region during phases 4 and 5, favored by upper-level convergence over tropical South America and an anticyclonic anomaly over southern South America. In September–November, enhanced rainfall and upper-level divergence are observed in the SACZ region during phases 7 and 8. These signals are generated primarily through the propagation of Rossby wave energy generated in the region of anomalous heating associated with the MJO. 相似文献
6.
Linear discriminant analysis to describe the relationship between rainfall and landslides in Bogotá, Colombia 总被引:1,自引:0,他引:1
Alfonso Mariano Ramos-Cañón Luis Felipe Prada-Sarmiento Mario Germán Trujillo-Vela Juan Pablo Macías Ana Carolina Santos-R 《Landslides》2016,13(4):671-681
Bogotá is located in the central Andean region of Colombia, which is frequently affected by landslide processes. These processes are mostly triggered during the rainy season in the city. This fact remarks the importance of determining what rain-derived parameters (e.g. intensity, antecedent rain, daily rain) are better related with the occurrence of landslides. For this purpose, the linear discriminant analysis (LDA), a technique derived from multivariate statistics, was used. The application of this type of analysis led to obtain simple mathematical functions that represent the probability of occurrence of landslides in Bogotá. The functions also allow to identify the most relevant variables derived from records of rainfall linked to the generation of landslides. A proof of concept using the proposed methodology was done using historic rainfall data from a 9-km2 area of homogenous climatology and geomorphology in the south part of Bogotá. Landslides needed to be grouped for the LDA. Each one of these grouping categories represents landslides that occurred in similar geomorphologic conditions. Another set of events with no landslides was generated synthetically. Results of the proof of concept show that rainfall parameters such as normalized rainfall intensity I MAP, normalized daily rainfall R MAP and rainy-days normal RDN have the best statistical correlation with the landslides observed in the zone of analysis. 相似文献
7.
Laboratory experiments on simulated faults in rocks clearly show the temperature dependence of dynamic rock friction. Since rocks surrounding faults are permeable, we have developed a numerical method to describe the thermo-mechanical evolution of the pre-seismic sliding phase which takes into account both the rate-, state- and temperature-dependent friction law and the heat advection term in the energy equation. We consider a laminar fluid motion perpendicular to a vertical fault plane and assume that fluids move away from the fault plane. A semi-analytical temperature solution which accounts for the variability of slip velocity and stress on the fault has been found. This solution has been generalized to the case of a time varying fluid velocity and then was used to include the thermal pressurization effect. After discretizing the temperature solution, the evolution of the system is obtained by the solution of a system of first order differential equations which allows us to determine the evolution of slip, slip rate, friction coefficient, effective normal stress, temperature and fluid velocity. The numerical solutions are found using a Runge-Kutta method with an adaptative stepsize control in time. When the thermal pressurization effects can be neglected, the heat advection effect gives rise to a delay, with respect to the purely conductive case, of the earthquake occurrence time. This delay increases with increasing permeability H of the system. When the thermal pressurization effects are taken into account the situation is opposite, i.e. the onset of instability tends to precede that of the purely conductive case. The advance in the time of occurrence of instability increases with increasing coefficient of thermal pressurization. In the small permeability range (H ≤ 10?18 m2), the seismic moment and nucleation length of the pre-seismic phase are significantly smaller than those predicted by the purely conductive model. 相似文献
8.
The H2O, CO2 and H2S outputs at the Solfatara of Pozzuoli have been measured and a map of the exhaling areas has also been made. The energy released at the surface by the fluids has been estimated to be 1019 ergs/day.The presence of aquifers at Phlegraean Fields increases the phreatic and phreatomagmatic explosion risk.Our results suggest that even if an uprising magma may interact with water at depth, an explosion could occur only at the shallow levels of a few hundred meters. Since the transfer of energy toward the surface is favoured by the presence of fractures, a detailed analysis of the deep fracture network would help to evaluate the risk levels of the various areas of Phlegraean Fields. 相似文献
9.
An automatic system for the continuous monitoring of CO2, H2S, SO2 and meteorological parameters in atmosphere has been developed. The system has been tested in the laboratory in order to verify the stability and reliability of each sensor and of the whole system. A field test for a period of one month, at the Solfatara of Pozzuoli has also been carried out. The acquired data during the field test reveal a correlation between the wind speed and the concentrations of CO2, H2S, and SO2 in the atmosphere. With a wind speed of over 4 ms-1 the concentration of the three gases reached constant background values of 600 ppm for CO2 and about 2 ppm vol. for H2S and SO2. The different ratios of H2S/SO2 measured in the fumaroles (~100) and in the atmosphere (1–0.1) clearly indicate that H2S is oxidized to SO2 during the transport. 相似文献
10.
Going quantitative with 4D seismic analysis 总被引:1,自引:0,他引:1
It is demonstrated that time‐lapse seismic signatures can be directly calibrated with historical data from producing and injecting wells via a reservoir simulator, material balance calculation or simply using the hard data. When this procedure is applied to a field over which two or more repeat surveys have been shot at different calendar times, the correlation coefficients that link the seismic difference signatures to the reservoir's pressure and saturation variations are determined. By utilizing several seismic attributes that respond differently to reservoir perturbations, pressure and saturation changes are then independently estimated. The approach is tested on synthetic data and then on data from the Schiehallion Field on the UK continental shelf, with favourable results. 相似文献