Episodes Of Deflation Research Articles

Monetary union effects on high inflation episodes

AbstractThis paper analyses whether monetary union membership reduces the duration of high inflation episodes (HIEs). The study uses survival models estimated on a sample of 190 countries over the period 1950M01 to 2022M12. The results show that despite the often‐cited issue of the heterogeneity of member countries, monetary unions significantly reduce the duration of HIEs, but not deflation episodes. This result remains robust to a battery of tests and is valid for both developed and developing countries. Furthermore, the results show that giving up monetary sovereignty in favour of an independent common central bank is more effective in terms of price stability than adopting inflation targeting. However, for countries seeking to preserve their monetary sovereignty, inflation targeting remains the best option for reducing the duration of HIEs. This performance of monetary unions in terms of price stability appears to be linked to the greater de facto independence of their central banks, the adoption of supranational fiscal rules, and the incentives to preserve the durability of the currency area. However, estimates show that the capacity of a monetary union to limit HIEs among its members diminishes as it expands to include new countries.

Magma fizz: Tremor during the Kīlauea summit reservoir decompression

Typical eruptions at Kīlauea volcano involve the evacuation of magma from the summit and/or south caldera reservoirs towards the East or Southwest rift zones. The reservoir drainage provokes the summit deflation, and on extreme occasions, such as in 2018, the summit caldera collapse. Systematically, seismic tremor, often with a particular multichromatic spectral signature characterized by frequency gliding, accompanies summit deflation episodes. In 2018, this type of continuous tremor accompanied the steady subsidence stage, whereas discrete earthquakes dominated the collapse stage. In this work, we aim to understand the source mechanism of the syn-deflation tremor of 2018. To locate the seismic source, we develop a novel machine-learning-based algorithm as an alternative to the amplitude source location technique. We use a large high-resolution catalog to resolve a composite amplitude decay function. Under these conditions, our method outperforms the traditional technique. We locate the tremor source 1 km below the eastern perimeter of the Halema‘uma‘u crater, which coincides with the position of the summit magma reservoir, as determined in many other studies. Furthermore, we model the seismic source as pressure oscillations driven by gas porous flow at the roof of the reservoir. In this model, gas accumulates temporarily in many gas pockets between the magma and the roof. Our modeling shows that the gas flux is responsible for the tremor amplitude modulations, whereas the gas pocket thickness controls the frequency variations. Beyond a critical point of depressurization, the magma cannot contribute further to the tremor oscillations via decompression-driven degassing, nor support the roof above it, resulting in rock failure. This work advances our understanding of magma-degassing dynamics and tremor generation at Kilauea volcano, and provides novel seismological techniques for volcano seismology monitoring and research.

GNSS-based long-term deformation at Mount Etna volcano (Italy)

We estimated a long-term velocity field for Mount Etna volcano by taking into account a dense GNSS dataset collected during the 2004.42 - 2018.95 period. To properly isolate the volcanic deformation from the background tectonic one, we defined a new local reference frame (termed MERF23) by using 32 stations mainly located in north-western and south-eastern Sicily. The computed long-term velocity field well highlights contrasting patterns between the north-western flank and the eastern one. The north-western flank was characterized by a general radial pattern with small deformations, mainly related to inflation and deflation episodes occurred during the investigated period. The eastern flank was characterized by a vigorous seaward motion, with rates ranging from ∼60 mm/yr on the Pernicana fault (northern boundary) to ∼29 mm/yr along the Aci Trezza fault (southern boundary), clearly evidencing as flank instability remains by far the predominant type of deformation at Mount Etna. A small contraction along the peripheral base of the volcano, coupled with a small uplift has been also detected; both patterns lend credit to the concurrent action of different processes as local and regional tectonics as well as long-term magmatic doming.

Combined volcano-tectonic processes for the drowning of the Roman western coastal settlements at Campi Flegrei (southern Italy)

The active Campi Flegrei caldera in southern Italy has a remarkably long history of coexistence between volcanism and human settlements, and it is famous for its peculiar slow ground movement called bradyseism, i.e. episodes of inflation and deflation of the caldera floor due to magmatic and/or hydrothermal processes. This natural phenomenon has interacted with the civilization that inhabited this strategic and fertile area, especially in Roman times, when the sinking of the coast hindered the flourishment of Puteoli and Baiae coastal towns. The drowning of a large part of Republic-early Imperial Roman coastal buildings, west of the modern Pozzuoli town, is classically used to illustrate the bradyseism activity. In this paper, we investigate the spatial variability and the role of this phenomenon, demonstrating that the caldera deflation alone cannot account for the submersion of Roman facilities in the western sector where the harbour structures of Portus Iulius and luxury villas of the Baianus Lacus presently lie beneath sea level. On the contrary, the sinking of this area is mainly the result of the activity of volcano-tectonic faults. We restored the topography to 100 BCE using archaeological and high-resolution topographic data. Results show that the several metres of vertical displacement recorded in the Baia area in the last 2100 yr were mainly produced by the activity of normal faults and secondarily by caldera deflation, the former including the long-lived Baia Fault and the younger normal faults associated with the Monte Nuovo eruption at 1538 CE.Graphical

¿Pico o meseta? La evolución de los salarios reales urbanos en Argentina durante la Primera Globalización (1898-1913)

In this essay, we propose a new estimation of Argentina’s real wages in the second phase of the first globalization (1895-1913). Using new sources of the period, we propose an estimation of the evolution in the price index and the wages of two urban labor categories in the economic structure (unskilled workers and skilled employees) for the Argentine provinces. The results tend to show a general growth in wages along the period. Between 1895 and 1903 this expansive dynamic is related to a big deflation episode after 1897 and the nominal wages recovery after the 1890 crisis. From 1904 to 1913, the wages grew slower, but the general index showed an improvement, related to a process of modernization on the labor structure, that resulted in a considerable skill level improvement among the workers. Provincial datasets show a wide diversity of trends at subnational level, including sharp rises, moderate increase and stagnation along the period. We suggest that this movement of wages is the result of an externality of an endogenous dynamic of the growth of regional economies.

Deformation and stress in hydrothermal regions: The case of a disk-shaped inclusion in a half-space

Hydrothermal regions are affected by a wide variety of phenomena, including ground inflation and deflation episodes. Among them, calderas offer the opportunity to study the complex interactions between magmatic processes at depth and permeable rocks saturated with fluids in the upper sedimentary layers. One of such regions is the Campi Flegrei caldera in southern Italy, where several source models have been applied over the years to reproduce the ground displacement and seismicity observed during the most recent phase of major unrest (1982–1984). The present work aims at introducing a new source model consisting of a thermo-poro-elastic inclusion embedded in a homogeneous poroelastic half-space. The inclusion is meant to represent a permeable rock layer stressed and strained by hot and pressurized volatiles released upward by an underlying magmatic reservoir and is modeled as a thin horizontal disk inside which a sudden change of temperature and pore pressure occurs. We provide semi-analytical solutions for the displacement and stress fields both within and outside the source and check them by comparison with those obtained through a fully numerical approach. Results provided by our model are compared with two other deformation source models often used to describe volcanic environments in terms of pressurized cavities describing a spherical magma chamber (Mogi source) or a sill-like magma intrusion (Fialko source). For the Campi Flegrei 1982–84 unrest, our model provides a better reproduction of ground deformation data and manages to explain the widespread presence of compressive focal mechanisms, since the stress field promoted both inside and outside the thermo-poro-elastic inclusion is very different from pressurized cavities.

Bridging the Gap From Caldera Unrest to Resurgence

Calderas often inflate up to a few metres for weeks to years, which is an evidence of short-term unrest. Some calderas also show a larger uplift (up to a thousand metres), achieved on the longer-term (hundreds to thousands of years), testified by a resurgent dome or block. How the short-term inflation relates to long-term resurgence is still poorly understood, even though established views consider the two processes distinct. This study exploits the longer deformation time series now available for several calderas, as well as the better understanding of magmatic processes and their evolution, to try to bridge the gap between these two scales of uplift. Available data challenge established views, suggesting that resurgence, rather than being produced by constant or continuous uplift, is the net cumulated result of tens to thousands distinct episodes of inflation, even interrupted by deflation episodes, as observed on short-term unrest. These inflation episodes are ascribed to distinct pulses of shallow magma emplacement, with most of the magma remaining intruded, especially in felsic calderas. This supports an incremental growth of magmatic systems, consistently with what observed below resurgent calderas and what inferred for plutons. Comparing the uplift (as expression of the intrusive record) and eruptive histories or resurgent calderas opens new exciting research paths to understand the causal relationships between intruded and erupted magma at a given caldera, thus enhancing its long-term eruptive forecast.

A New Model of Campi Flegrei Inflation and Deflation Episodes Based on Brownian Motion Driven by the Telegraph Process

A stochastic model to describe the vertical motions in the Campi Flegrei volcanic region is proposed herein, consisting of a Brownian motion process driven by a generalized telegraph process. Knowledge on the probability law of this process enables quantitative investigation of some basic parameters regulating the inflation/deflation processes, such as velocities and time constants. Statistical analysis was carried out based on linear regression with constraints. Predictions of ground displacements and their changing tendency at future time instants were also made. Finally, a statistical test on the Brownian component of the process confirmed the goodness of the model.

Forecasting the duration of short‐term deflation episodes

AbstractThe paper proposes a simulation‐based approach to multistep probabilistic forecasting, applied for predicting the probability and duration of negative inflation. The essence of this approach is in counting runs simulated from a multivariate distribution representing the probabilistic forecasts, which enters the negative inflation regime. The marginal distributions of forecasts are estimated using the series of past forecast errors, and the joint distribution is obtained by a multivariate copula approach. This technique is applied for estimating the probability of negative inflation in China and its expected duration, with the marginal distributions computed by fitting weighted skew‐normal and two‐piece normal distributions to autoregressive moving average ex post forecast errors and using the multivariate Student t copula.

Evaluating the Macroeconomic Effects of the ECB's Unconventional Monetary Policies

We quantify the macroeconomic effects of the European Central Bank’s unconventional monetary policies using a dynamic stochastic general equilibrium model, which includes the shadow Eonia rate. Extracted from the yield curve, this shadow rate provides an unconstrained measure of the overall stance of monetary policy. Counterfactual analyses show that, without unconventional measures, the euro area would have suffered (i) a cumulative loss of output of around 19% of its pre-crisis level since the Great Recession, (ii) a deflation episode in 2009 and (iii) a slowdown in price increases in 2015 and 2016.

Investigations on the role of leukotrienes in remote hind limb preconditioning-induced cardioprotection in rats

The cardioprotective effects of remote hind limb preconditioning (RIPC) are well established, but its mechanisms still remain to be explored. Therefore, the present study was aimed to explore the possible involvement of 5-lipoxygenase-derived leukotrienes in RIPC. The hind limb was tied by a pressure cuff and was subjected to four episodes of inflation and deflation (5min each) to induce remote hind-limb preconditioning. Thereafter, the hearts were isolated and were subjected to global ischemia (30min) followed by reperfusion (120min) on the Langendorff apparatus. The extent of myocardial injury was assessed by measuring lactate dehydrogenase (LDH) and creatine kinase (CK) levels in the coronary effluent; the infarct size using TTC staining, and the hemodynamic parameters including LVDP, dp/dtmax and dp/dtmin. RIPC significantly decreased ischemia and reperfusion-induced increase in LDH, CK release, infarct size and improved LVDP, dp/dtmax and dp/dtmin. Administration of montelukast, leukotriene receptor antagonist (10 and 20mg/kg) and zileuton, 5-lipoxygenase inhibitor, (2.5 and 5mg/kg) abolished RIPC-induced cardioprotection. It may be concluded that hind limb ischemia stimulates 5-lipoxygenase to release leukotrienes which may elicit cardioprotection by humoral or neurogenic pathway.

Financial crisis, US unconventional monetary policy and international spillovers

We study the impact of US quantitative easing (QE) on both the emerging and advanced economies, estimating a global vector error-correction model (GVECM). We focus on the effects of reductions in the US term and corporate spreads. The estimated effects of QE are sizeable and vary across economies. First, we find the QE impact from reducing the US corporate spread to be more important than that from lowering the US term spread, consistent with Blinder's (2012) argument. Second, counterfactual exercises suggest that successive US QE measures might have prevented episodes of prolonged recession and deflation in the advanced economies. Third, the estimated effects on the emerging economies are diverse but generally larger than those found for the United States and other advanced economies. The estimates suggest that US monetary policy spillovers contributed to the overheating in Brazil, China and some other emerging economies in 2010 and 2011, but supported their respective recoveries in 2009 and 2012. These heterogeneous effects point to unevenly distributed benefits and costs of cross-border monetary policy spillovers.

Financial Crisis, US Unconventional Monetary Policy and International Spillovers

We study the impact of the US quantitative easing (QE) on both the emerging and advanced economies, estimating a global vector error-correction model (GVECM) and conducting counterfactual analyses. We focus on the effects of reductions in the US term and corporate spreads. First, US QE measures reducing the US corporate spread appear to be more important than lowering the US term spread. Second, US QE measures might have prevented episodes of prolonged recession and deflation in the advanced economies. Third, the estimated effects on the emerging economies have been diverse but often larger than those recorded in the US and other advanced economies. The heterogeneous effects from US QE measures indicate unevenly distributed benefits and costs.

Very long period conduit oscillations induced by rockfalls at Kilauea Volcano, Hawaii

Eruptive activity at the summit of Kilauea Volcano, Hawaii, beginning in 2010 and continuing to the present time is characterized by transient outgassing bursts accompanied by very long period (VLP) seismic signals triggered by rockfalls from the vent walls impacting a lava lake in a pit within the Halemaumau pit crater. We use raw data recorded with an 11‐station broadband network to model the source mechanism of signals accompanying two large rockfalls on 29 August 2012 and two smaller average rockfalls obtained by stacking over all events with similar waveforms to improve the signal‐to‐noise ratio. To determine the source centroid location and source mechanism, we minimize the residual error between data and synthetics calculated by the finite difference method for a point source embedded in a homogeneous medium that takes topography into account. We apply a new waveform inversion method that accounts for the contributions from both translation and tilt in horizontal seismograms through the use of Green's functions representing the seismometer response to translation and tilt ground motions. This method enables a robust description of the source mechanism over the period range 1–1000 s. The VLP signals associated with the rockfalls originate in a source region ∼1 km below the eastern perimeter of the Halemaumau pit crater. The observed waveforms are well explained by a simple volumetric source with geometry composed of two intersecting cracks including an east striking crack (dike) dipping 80° to the north, intersecting a north striking crack (another dike) dipping 65° to the east. Each rockfall is marked by a similar step‐like inflation trailed by decaying oscillations of the volumetric source, attributed to the efficient coupling at the source centroid location of the pressure and momentum changes induced by the rock mass impacting the top of the lava column. Assuming a simple lumped parameter representation of the shallow magmatic system, the observed pressure and volume variations can be modeled with the following attributes: rockfall volume (200–4500 m3), length of magma column (120–210 m), diameter of pipe connecting the Halemaumau pit crater to the subjacent dike system (6 m), average thickness of the two underlying dikes (3–6 m), and effective magma viscosity (30–210 Pa s). Most rockfalls occur during episodes of sustained deflation of the Kilauea summit. The mass loss rate in the shallow magmatic system is estimated to be 1400–15,000 kg s−1 based on measurements of the temporal variation of VLP period in the two large rockfalls that occurred on 29 August 2012.

Characterization of open and closed volcanic systems in Indonesia and Mexico using InSAR time series

AbstractWe use 2007–2011 Advanced Land Observing Satellite (ALOS) data to perform an arc‐wide interferometric synthetic aperture radar (InSAR) time series survey of the Trans‐Mexican Volcanic Belt (TMVB) and to study time‐dependent ground deformation of four Indonesian volcanoes selected following the 2007–2009 study of Chaussard and Amelung (2012). Our objectives are to examine whether arc volcanoes exhibit long‐term edifice‐wide cyclic deformation patterns that can be used to characterize open and closed volcanic systems and to better constrain in which cases precursory inflation is expected. We reveal deformation cycles at both regularly active and previously inactive Indonesian volcanoes, but we do not detect deformation in the TMVB, reflecting a lower activity level. We identify three types of relationships between deformation and activity: inflation prior to eruption and associated with or followed by deflation (Kerinci and Sinabung), inflation without eruption and followed by slow deflation (Agung), and eruption without precursory deformation (Merapi, Colima, and Popocatépetl; at Merapi, no significant deformation is detected even during eruption). The first two cases correspond to closed volcanic systems and suggest that the traditional model of magmatic systems and eruptive cycles do apply to andesitic volcanoes (i.e., inflation and deflation episodes associated with magma accumulation or volatile exsolution in a crustal reservoir followed by eruptions or in situ cooling). In contrast, the last case corresponds to open volcanic systems where no significant pressurization of the magmatic reservoirs is taking place prior to eruptions and thus no long‐term edifice‐wide ground deformation can be detected. We discuss these results in terms of InSAR's potential for forecasting volcanic unrest.

Effect of Ischaemic Postconditioning on Recovery of Left Ventricular Contractile Function after Acute Myocardial Infarction

This study investigated whether ischaemic postconditioning can improve recovery of myocardial contractile function in acute myocardial infarction patients 1 week and 6 months after angioplasty. A total of 62 patients undergoing direct percutaneous coronary intervention after acute myocardial infarction were randomly assigned to receive four episodes of inflation and deflation of the angioplasty balloon in the early reperfusion period (postconditioned group, n = 32), or no additional intervention (control group, n = 30). Two-dimensional size and left ventricular (LV) global and regional contractile functions were then evaluated by echocardiography at 1 week and 6 months after angioplasty. At 1 week, there were no significant differences in left atrial diameter, LV enddiastolic diameter, LV end-diastolic volume, cardiac output, LV ejection fraction or wall motion score index between the two groups. At 6 months, LV ejection fraction was significantly increased and the wall motion score index significantly reduced in the postconditioned group compared with the control group. Ischaemic postconditioning can improve long-term LV contractile function 6 months after reperfusion following acute myocardial infarction.

E0569 Postconditioning effect on reperfusion Arrhythmia of ST-segment elevation acute myocardial infarction

ObjectiveTo study postconditioning effects during the first minutes of reperfusion in STEMI patients undergoing emergency percutaneous coronary intervention (PCI) on the myocardial reperfusion Arrhythmia.MethodsBetween Oct. 2006 and Jan. 2009 at...

InSAR Permanent Scatterer analysis reveals fault re-activation during inflation and deflation episodes at Campi Flegrei caldera

Permanent Scatterers Synthetic Aperture Radar Interferometry (PSInSAR) and Global Position System (GPS) are applied to investigate the most recent surface deformation of the Campi Flegrei caldera. The PSInSAR analysis, based on SAR data acquired by ERS-1/2 sensors during the 1992–2001 time interval and by the Radarsat sensor during 2003–2007, identifies displacement patterns over wide areas with high spatial resolution. GPS data acquired by the Neapolitan Volcanic Continuous GPS network provide detailed ground velocity information of specific sites. The satellite-derived data allow us to characterize the deformation pattern that affected the Campi Flegrei caldera during two recent subsidence (1992–1999) and uplift (2005–2006) phases. PSInSAR results show the re-activation of the caldera ring-faults, intra-caldera faults, and eruptive fissures. We discuss the results in the light of the available volcanological, structural and geophysical data and propose a relationship between the structures activated during the recent unrest episodes and those responsible for the recent (<3.8–4ka) volcanism. The combined interpretation of the collected data show that (a) the caldera consists of two sectors separated by a N–S striking faulting zone and (b) the intra-caldera NW–SE faults and eruptive fissures in the central-eastern sector re-activated during the studied unrest episodes and represent possible pathways for the ascent of magma and/or gas to the surface. In this sector, maximum horizontal strain, recent volcanism (3.8–4ka), active degassing and seismicity concentrate. The fault re-activation is related to the dynamics of the caldera and not to tectonic stress. The deformation fields of the uplift and subsidence episodes are consistent with hydrothermal processes and degassing from a magmatic reservoir that is significantly smaller than the large (∼40km3) magma chamber responsible for the caldera formation. We provide evidence that the monitoring of the horizontal and vertical components of deformation improves the identification of active, aseismic faults. Accordingly, we suggest that future ground deformation models should include the re-activation of the detected structures.

Magma degassing triggered by static decompression at Kīlauea Volcano, Hawai‘i

During mid‐June 2007, the summit of Kīlauea Volcano, Hawai‘i, deflated rapidly as magma drained from the subsurface to feed an east rift zone intrusion and eruption. Coincident with the deflation, summit SO2 emission rates rose by a factor of four before decaying to background levels over several weeks. We propose that SO2 release was triggered by static decompression caused by magma withdrawal from Kīlauea's shallow summit reservoir. Models of the deflation suggest a pressure drop of 0.5–3 MPa, which is sufficient to trigger exsolution of the observed excess SO2 from a relatively small volume of magma at the modeled source depth beneath Kīlauea's summit. Static decompression may also explain other episodes of deflation accompanied by heightened gas emission, including the precursory phases of Kīlauea's 2008 summit eruption. Hazards associated with unexpected volcanic gas emission argue for increased awareness of magma reservoir pressure fluctuations.

Moderate Inflation and the Deflation–Depression Link

Recent research has concluded that the historical evidence only provides weak support for the contention that deflation episodes are harmful to economic growth. In this paper, we revisit this relationship by allowing for inflation and growth to have a nonlinear specification dependent on inflation levels. In particular, we allow for the possibility that high inflation is negatively correlated with growth, while a positive relationship exists over the range of negative to moderate inflation. Our results confirm a positive relationship between inflation and growth at moderate inflation levels, and support the contention that the relationship between inflation and growth is nonlinear over the entire sample range.