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This paper studies the network structure and fragmentation of the Argentinean interbank market. Both the unsecured (CALL) and the secured (REPO) markets are examined, applying complex network analysis. Results indicate that, although the secured market has less participants, its nodes are more densely connected than in the unsecured market. The interrelationships in the unsecured market are less stable, making its structure more volatile and vulnerable to negative shocks. The analysis identifies two 'hidden' underlying sub-networks within the REPO market: one based on the transactions collateralized by Treasury bonds (REPO-T) and other based on the operations collateralized by Central Bank (CB) securities (REPO-CB). The changes in monetary policy stance and monetary conditions seem to have a substantially smaller impact in the former than in the latter 'sub-market'. The connectivity levels within the REPO-T market and its structure remain relatively unaffected by the (in some period pronounced) swings in the other segment of the market. Hence, the REPO market shows signs of fragmentation in its inner structure, according to the type of collateral asset involved in the transactions, so the average REPO interest rate reflects the interplay between these two partially fragmented sub-markets. This mixed structure of the REPO market entails one of the main sources of differentiation with respect to the CALL market., 28 pages, 11 figures, 3 tables

25th European VLBI Group for Geodesy and Astronomy Working Meeting, 14-18 March 2021, In 2020, the IVS observed for a second year an operational 24-hr VGOS session series (VGOS-O) at a bi-weekly cadence. The total number of sessions amounts to 24 for the full year; the network size was between 8 and 9 stations. In February 2020, we began an Intensive-type VGOS session series (VGOS-V2) of one-hour observing designed to measure UT1. There were a total of 21 VGOS-V2 sessions that were scheduled in the weeks when there was no 24-hr VGOS session and ran concurrently with the legacy S/X INT1 sessions. The VGOS-V2 sessions generally included the KOKEE12M¿WETTZ13S baseline with GGAO12M, MACGO12M, and WESTFORD being tagged along or scheduled in depending on their availability. There were a total of 21 VGOS-V2 sessions. For both VGOS-O and VGOS-V2 sessions we discuss the scheduling, correlation, and analysis.We contrast the 24-hr VGOS sessions with 24-h S/X sessions of similar size. For the VGOS-V2 sessions we compare UT1 estimates with those obtained from the corresponding S/X Intensives

25th European VLBI Group for Geodesy and Astronomy Working Meeting, 14-18 March 2021, The processing of geodetic VLBI experiments involving both S/X and VGOS stations is highly desirable for a multitude of reasons. Beyond the express purpose of obtaining geodetic ties between existing S/X stations and the rapidly expanding network of VGOS stations, a period of overlap and integration between the two systems is beneficial in order to help preserve reference frame continuity during the transition from the S/X to VGOS network, as well as to provide an opportunity to study any systematic differences between the two. Therefore, it is important to correlate and fringe-fit data collected contemporaneously by both S/X and VGOS stations to obtain delay observables on mixed baselines. A brief overview of one possible implementation of this process will be presented, describing correlation (including the use of the DiFX zoom-bands feature) along with the peculiarities of data handling on mixed S/X-VGOS baselines during post-processing with fourfit. Some results from the mixed-mode sessions RD2005 and RD2006 will be presented, and future prospects will be discussed

This paper studies the network structure and fragmentation of the Argentine interbank market. Both the unsecured (CALL) and the secured (REPO) markets are examined. The aim of this study is to understand their actual fragmentation, as well as its potential implications for monetary policy and financial stability. Applying network analysis, different underlying segments within the market are identified. We approximate the theoretical distribution that better fits the empirical degree distribution of the interbank loan networks. Based on standard topological metrics, it is found that, although the secured market has less participants, its nodes are more densely connected than in the unsecured market. In addition, the interrelationships in the unsecured market are less stable, as it was witnessed during the 2018 currency crisis, making its structure more volatile and vulnerable to negative shocks. The analysis identifies two "hidden" underlying sub-networks within the REPO market: one based on the transactions collateralized by Treasury bonds (REPO-T) and other based on the operations collateralized by Central Bank (CB) securities (REPO-CB). The connectivity indicators were significantly more stable in the REPO-T market than in the REPO-CB segment. The changes in monetary policy stance and monetary conditions seem to have a substantially smaller impact in former than in the latter "sub-market". Hence, the connectivity levels within the REPO-T market remain relatively unaffected by the (in some period pronounced) swings in the other segment of the market. These results have implications in terms of the interpretation of the interest rates that arise from these markets.

25th European VLBI Group for Geodesy and Astronomy Working Meeting, 14-18 March 2021, Year 2020 was the culmination of a few earlier years of meticulous preparatory work for obtaining observations simultaneously with the legacy S/X and the VGOS networks as if they were a single, seamless network. The main goal of these so-called mixed-mode sessions is to determine the positions of the new VGOS stations in the terrestrial reference frame defined by the long-lived, stable legacy stations, thus effectively tying both networks together. Three mixed-mode sessions had been executed prior to 2020, each session adding one new small-step to the previous session to ensure technology development and advancement. Indeed, the first session involved a single VGOS station, Westford, participating in a standard R&D S/X observing network in tag-along mode in 2016. The second and third sessions involved the participation of two (add GGAO) and three (add KPGO) VGOS stations, respectively, in 2018, hence expanding from a station to a VGOS baseline and then a triangle, or closure. An important component of this progressive approach has been to identify, and where possible, solve software challenges and limitations, to then move forward with knowledge transfer to the IVS community. An ambitious plan was then launched in 2020 when, building on the success of the earlier sessions, a series of three mixed-mode sessions were run whereby the existing entire VGOS network of 8 stations joined in R&D-type 8-station S/X sessions, thus synthesizing a 16-station mixed-mode network. The main goal of these augmented sessions was to strengthen the network ties for the upcoming ITRF2020 realization. This presentation will focus on the goals of the original vision for the sessions, how the goals morphed to what became the reality, and the impact on the processing and software of these modifications; a lessons-learned perspective. We will conclude with what may a best way forward for 2021

American Geophysical Union (AGU) Fall Meeting, 13-17 December 2021, New Orleans, The International VLBI Service for Geodesy and Astrometry (IVS) currently employs a two-band VLBI system (legacy S/X system) as its operational system for product creation. Over the past decade a new VLBI system called VGOS (VLBI Global Observing System) has been under development and in recent years strides have been made to implement the new broadband system globally. A modernized station infrastructure has been (and will continue to be) established worldwide and in 2020 a fledgling network of 8-10 VGOS stations started observing in operational IVS sessions. It is anticipated that the global VGOS network will grow to 25 stations and more in the next couple of years. As part of the modernization process also other infrastructure components of the VLBI processing chain have been further developed, including the VGOS correlation and post-processing capabilities as well as VGOS data analysis. We will provide a status overview of the infrastructure realization efforts of the VGOS station network, the correlation centers and analysis, and we will present some initial results from the limited network VGOS sessions

American Geophysical Union (AGU) Fall Meeting, 13-17 December 2021, New Orleans, The next-generation VLBI system called VGOS (VLBI Global Observing System) is now operational. A network of 8 VGOS stations has been observing bi-weekly since 2019 under the auspices of the International VLBI Service for Geodesy and Astrometry (IVS) for the creation of standard geodetic products. Moreover, a subset of 2-4 of those VGOS stations has also been observing, starting in 2020, in a VLBI Intensives-like mode to assess the feasibility of earth¿s rotation (UT1) estimation using VGOS. Intensives are VLBI observations that are run on a daily basis using a single baseline, for instance, between Kokee Park Geophysical Observatory, Hawaii, and Wettzell Observatory, Germany, with the goal of near-real time monitoring of UT1. We will describe the VGOS observations, correlation, post-processing, and preliminary geodetic results, including UT1. We will compare the VGOS estimates to estimates from legacy VLBI and other geodetic techniques such as GNSS, when and where possible, to draw some conclusions on the precision and accuracy of the VGOS estimates

NEROC Fifth Annual Radio Science Symposium, 16-17 November 2020

El trabajo investiga empíricamente la respuesta de la actividad económica provincial y regional en Argentina a los shocks de política monetaria dados por cambios en la tasa de interés. Se encuentra que en Argentina existen heterogeneidades regionales, resultantes de efectos diferenciales de los shocks de política monetaria. A nivel regional los efectos son negativos y estadísticamente signicativos. A nivel provincial, 11 provincias muestran un impacto negativo y signicativo a los shocks de la tasa de interés sobre el empleo. No obstante, hay 13 provincias en las cuales el efecto no es estadísticamente signicativo, incluyendo las de mayor tamaño e importancia económica, la Ciudad Autónoma de Buenos Aires y Gran Buenos Aires, así como la provincia de Buenos Aires. Finalmente se utilizan métodos bayesianos para analizar los determinantes de los efectos heterogéneos encontrados en las diferentes provincias. Fil: Blanco, Emilio. Fil: Elosegui, Pedro. Fil: Izaguirre, Alejandro. Universidad de San Andrés. Fil: Montes Rojas, Gabriel. Universidad de Buenos Aires. Facultad de Ciencias Económicas.

Terrestrial Multidisciplinary distributed Observatories for the Study of Arctic Connections (T-MOSAiC) Workshop - Arctic Science Summit Week (ASSW), 31 March - 7 April 2017, Prague, Czech Republic

Final Ice, Climate, Economics - Arctic Research on Change (ICE-ARC), 27 November 2017, Barcelona

Final Ice, Climate, Economics - Arctic Research on Change (ICE-ARC), 27 November 2017, Barcelona

El trabajo desarrolla un Modelo Estructural con las principales características macroeconómicas de la economía ecuatoriana. Modela los principales canales de transmisión de una economía pequeña, abierta y dolarizada, altamente dependiente de la producción de petróleo y las remesas del exterior. Se estima por métodos bayesianos para el período 2001-2010. El modelo permite analizar los principales riesgos que afectan el desempeño macroeconómico, incluyendo los shocks externos. También se subraya el efecto de la política fiscal así como el papel independiente y significativo del valor agregado petrolero en la economía doméstica., The paper develops a Structural Model with the main macroeconomic features of the Ecuadorian economy. It models the main transmission channels of a small open and dollarized economy, highly dependent on oil production and foreign remittances. It is estimated by Bayesian methodsfor the period 2001- 2010. The framework highlights the main risks affecting the macroeconomic performance, including the importance of international shocks. It also underscores the importance of the fiscal policies and the independent and significant role of the oil value added in the domestic economy., Facultad de Ciencias Económicas

Ice, Climate, Economics - Arctic Research on Change (ICE-ARC) General Assembly, 19-20 October 2016, Tromsø, Norway

7th International Workshop on Sea Ice Data Assimilation and Verification, 5-7 April 2016, Frascati, Italy.-- 2 pages, The launch of the Soil Moisture and Ocean Salinity (SMOS) mission, in 2009, marked the dawn of a new type of space-based microwave observations. Although the mission was originally conceived for hydrological and oceanographic studies [1,2], SMOS is also making inroads in the cryospheric sciences. SMOS carries an L-band (1.4 GHz, or 21-cm wavelength), passive interferometric radiometer (the so-called MIRAS) that measures the electromagnetic radiation emitted by the Earth’s surface, at about 50 km spatial resolution, full polarization, continuous multi-angle viewing, large wide swath (1200-km), and with a 3-day revisit time at the equator, but more frequently at the poles. A significant difference of the L-band microwave radiometers with respect to higher frequency radiometers, such as SSMI/AMSR-E/AMSR-2, is that the former can also “see through the ice.” That is because ice is more transparent (i.e., optically thinner) at 1.4 GHz than at higher frequencies (19-89 GHz). In radiometric terms, the brightness temperature measured by an L-band antenna radiometer does not correspond to the emissivity of the topmost surface layer but of a larger range of deeper layers within the ice (about 60 cm, depending on ice conditions). Thanks to that increased penetration in the medium, L-band radiometers can provide, for the first time, thin ice thickness from space [3, 4]. A novel radiometric method to determine sea ice concentration (SIC) is presented. The method exploits the distinctive radiative properties of sea ice and seawater when observed at low microwave frequencies and from a range of incidence angles, to discern both media. The Bayesian-based Maximum Likelihood Estimation (MLE) approach is used to retrieve SIC. The advantage of this approach with respect to the classical linear inversion is that the former takes into account the uncertainty of the tie-point measured data in addition to the mean value, while the latter only uses a mean value of the tie-point data. When thin ice is present, the SMOS algorithm underestimates SIC due to the low opacity of the ice at this frequency. However, using a synergistic approach with data from other satellite sensors, it is possible to obtain accurate thin ice thickness estimations with the Bayesian-based method. Despite its lower spatial resolution relative to SSMI or AMSR-E, SMOS-derived SIC products are little affected by the atmosphere, the snow (almost transparent at L-band) and variations on the temperature of the ice. This new dataset can contribute to complement ongoing monitoring efforts in the Arctic Cryosphere. Moreover, with new algorithms, recently developed at BEC to improve the SMOS quality, we can now, for the first time, produce cold water SSS maps from SMOS data. These algorithms include: improvement of the image reconstruction by a reduction of sidelobe levels and ripples caused by abrupt changes of brightness temperatures (at level 1); empirical correction of the instrumental systematic biases (land-sea and ice-sea contamination) (at level 2); use of synergistic and multifractal approaches for increasing the spatial and temporal resolution (at levels 3 and 4). The new maps will be presented at the conference together with a thorough assessment of their quality., [1] Font, J.; Camps, A.; Borges, A.; Martin-Neira, M.; Boutin, J.; Reul, N.; Kerr, Y.; Hahne, A. & Mecklenburg, S. SMOS: The Challenging Sea Surface Salinity Measurement From Space Proceedings of the IEEE, no. 5, 2010, 98, 649 -665 [2] Kerr, Y.; Waldteufel, P.; Wigneron, J. P..; Delwart, S.; Cabot, F.; Boutin, J.; Escorihuela, M.J..; Font, J.; Reul, N.; Gruhier, C.; Juglea, S.; Drinkwater, M.; Hahne, A.; Martin-Neira, M. & Mecklenburg, S. The SMOS mission: New tool for monitoring key elements of the global water cycle Proc. IGARSS 2010, no. 5, 2010, 98, 666-687 [3] Kaleschke, L., Tian-Kunze, X., Maass, N., Mäkynen, M., and Drusch, M.: Sea ice thickness retrieval from SMOS brightness temperatures during the Arctic freeze-up period, Geophys. Res. Lett., doi:10.1029/ 2012GL050916, 2012. [4] Huntemann, M., Heygster, G., Kaleschke, L., Krumpen, T., Mäkynen, M., and Drusch, M.: Empirical sea ice thickness retrieval during the freeze up period from SMOS high incident angle observations, The Cryosphere Discuss., 7, 4379–4405, 2013

2nd SMOS Science Conference, 25-29 May 2015, Madrid), Spain.-- 1 page

Second ICE-ARC General Assembly, 20- 22 October 2015, Bolonia

Seventeenth Session of the GCOS/GOOS/WCRP Ocean Observations Panel For Climate (OOPC-17), 21-23 July 2014, Barcelona, Spain

First Ice, Climate, Economics - Arctic Research on Change General Assembly Meeting, 19-21 November 2014, Barcelona.-- 1 page, 9 figures, SATICE-type buoys are geodetic-quality GPS systems capable of collecting continuous high-precision GPS data while drifting on sea ice. The buoy core sensor is a dual-frequency, carrier-beat-phase GPS receiver that provides continuous (0.1 Hz), three-dimensional position estimates with cm-level precision in a well-defined geodetic reference frame. Besides highquality GPS measurements, other geophysical auxiliary observations such meteorological, ice, and upper ocean are also acquired. Heretofore, we have designed, built, deployed, and operated five SATICE buoys, in the Western Arctic (Chukchi Sea and Beaufort Sea), two of which are currently active in the Beaufort. Data from these buoys are helping us gain an improved understanding of Arctic sea ice physics and ocean dynamics. As part of our contribution to ICE-ARC, we will build a new series of improved SATICE buoys and deploy them pan-Arctic. SATICE buoy technology is described below, This work was partly supported by ICE-ARC/FP7, SATICE/ESF, and the Spanish Ministry of Science and Innovation (MICINN; now MINECO)

Presentación para la Seventeenth Session of the GCOS/GOOS/WCRP Ocean Observations Panel For Climate (OOPC-17), 21-23 July 2014, Barcelona, Spain.-- 20 pages

American Geophysical Union (AGU) Fall Meeting, 9-13 December 2013, San Francisco, Slow-slip events were first discovered on the deeper Cascadia subduction interface about a decade ago. Since then, slow-slip events have been observed at various subduction environments including Cascadia, Nankai, Alaska, New Zealand, Mexico, and Costa Rica. Conspicuously absent from this list, however, is the Sumatran subduction zone, along which no slow-slip events have yet been discovered. As one of the most active subduction zones currently in the world, the Sumatran subduction zone has experienced a series of great earthquakes over the last decade, along with numerous moderate and smaller earthquakes. We conducted a systematic search for transient aseismic slip in time series from the Sumatran GPS Array (SuGAr) between 2002 and 2012. We reprocessed the time series using GIPSY 6.2, and included the most up-to-date atmosphere and ocean models in processing to reduce day-to-day scatter of the raw time series. The raw data are dominated signals from coseismic and postseismic deformation. In order to search for much smaller transient signals, on the order of a few millimeters, we estimated and removed long-term background rates simultaneously with a large number of earthquake parameters, thus generating daily residuals. After our careful inspection of the daily residuals, we concluded that no episodic slip events have been recorded. Regarding non-episodic slip events, one station (BSAT) recorded a rate change in a few months immediately after the 2004 Sumatra-Andaman earthquake. Some other nearby stations that were installed later recorded a portion of this change. However, there were no other independent observations to confirm if this signal was indeed slow-slip. Except this suspicious signal, no other positive evidence could provide support for the occurrence of slow-slip events in Sumatra. This may indicate that slow-slip events have not occurred on the Sunda megathrust over the last decade, but may also highlight the limitation of the SuGAr network to detect slow-slip events. In testing the capability of the SuGAr network to resolve slow-slip events along the Sumatran subduction interface similar to those observed at Cascadia (~Mw 6.7) and Nankai (~Mw 6.0), we show that the current SuGAr network cannot fully resolve slow-slip events in the deeper part. This information is useful for augmenting and strengthening the network in the future

European Space Agency (ESA) Living Planet Symposium, 9-13 September 2013, Edinburgh, On November 2, 2009, the European Space Agency's (ESA) launched the Soil Moisture and Ocean Salinity (SMOS) satellite carrying a microwave synthetic aperture radiometer working at 1.4 GHz (wavelength of 21 cm). The main objective of the mission is to provide Sea Surface Salinity (SSS) and Soil Moisture (SM) observations, with a spatial resolution of 30-50 km, and an accuracy suited for climate studies. Many studies have been performed studying the quality of the retrieved SSS and the SM measurements. However, SMOS can also measure the ice thickness, over ice, with good accuracy for a thin sea ice layer (less about 0.5 cm). These measurements could be complementary to CryoSat, which can best measure ice thickness for thicker ice. This work will present a comparison between ice thickness measured by SMOS and in situ measurements from buoys and other satellite measurements. Moreover, the comparison will also be performed with Aquarius NASA's radiometer, launched on June 2011, which has three real aperture radiometers at 1.4GHz. The insitu dataset used for the comparison and validation of the methodology will be one obtained with Ice Mass Balance (IMB) and other buoys deployed as part of the SATICE project (http://satice.icm.csic.es/) in the western Arctic Ocean. SSMI data and CryoSat data will also be used for comparison

7ª Asamblea Hispano Portuguesa de Geodesia y Geofísica, 25-28 de junio de 2012, Donostia - San Sebastián

IPY2012 Conference Montréal. From Knowledge to Action, 22-27 April 2012, Montréal, Canada, The marine environment of the Arctic Ocean is under profound transformation, as clearly shown by observations and model predictions across a range of disciplines. The rapid decline in sea ice extent and volume during the boreal summers is a prime example. To improve our understanding of the key physical processes that drive change in this region, it is crucial to monitor the complex ocean-cryosphere-atmosphere system. This presentation explores how sea ice is changing in this region by using a combined observational and modeling approach that builds heavily on the latest technological advances in Space Geodesy. We have developed a high-precision (i.e., few cm position accuracy), GPS-based autonomous platform suited to the challenging Arctic Ocean environment that enables determination of sea ice motions in three-dimensions with hightemporal sampling and, when deployed as a network, also high-spatial density. The platform includes a sea ice freeboard sensor and two-way communications, thus also enabling near-real time monitoring and remote data retrieval. We have deployed several prototypes of such platform for limited durations both in the Arctic Ocean and the Southern Ocean since 2009, and two full-blown, long-term systems, on the Chukchi Sea, during the boreal summer of 2011. Although monitoring of sea ice motions in this fast changing region goes back to the early days of satellite observations, these systems bring out a level of spatio-temporal detail that has never been seen before, which in turn allows us to question our present understanding of sea ice dynamics. We will describe the technology behind this novel platform, which could also be adapted to other applications that require sustained operations and observations in the Arctic environment, and present results pertaining to sea ice dynamics, Arctic Ocean tides, ocean dynamic topography, ocean currents, and sea ice freeboard, thickness, and mass balance, from the analysis of the GPS and freeboard data collected by those systems

Hill, Emma M. ... et al.-- 21 pages, 21 figures, 1 appendix, supporting information in http://onlinelibrary.wiley.com/doi/10.1029/2012JB009159/suppinfo, The M w 7.8 October 2010 Mentawai, Indonesia, earthquake was a "tsunami earthquake," a rare type of earthquake that generates a tsunami much larger than expected based on the seismic magnitude. It produced a locally devastating tsunami, with runup commonly in excess of 6m. We examine this event using a combination of high-rate GPS data, from instruments located on the nearby islands, and a tsunami field survey. The GPS displacement time series are deficient in high-frequency energy, and show small coseismic displacements (16m. Our modeling results show that the combination of the small GPS displacements and large tsunami can only be explained by high fault slip at very shallow depths, far from the islands and close to the oceanic trench. Inelastic uplift of trench sediments likely contributed to the size of the tsunami. Recent results for the 2011 M w 9.0 Tohoko-Oki earthquake have also shown shallow fault slip, but the results from our study, which involves a smaller earthquake, provide much stronger constraints on how shallow the rupture can be, with the majority of slip for the Mentawai earthquake occurring at depths of, This work was funded by the Earth Observatory of Singapore (EOS) and is EOS Contribution Number 37. The tsunami helicopter survey was partially supported by NSF RAPID CMMI-1105577. E.H. is partially supported by a Singapore National Research Foundation fellowship

7ª Asamblea Hispano Portuguesa de Geodesia y Geofísica, 25-28 de junio de 2012, Donostia - San Sebastián

AGU Fall Meeting 3–7 December 2012, San Francisco, California, Single-frequency GNSS data has not generally been used for high-accuracy geodetic applications since the 1990s, but there are significant advantages if single-frequency GNSS receivers can be usefully deployed for studies of fast-moving outlet glaciers. The cost for these receivers is significantly lower (~50%) than for dual-frequency receivers, a significant benefit given the high spatial density at which these system are deployed on the glacier and the high risk for damage or loss in the glacial environment. In addition, the size of the data files that need to be transferred from extremely remote locations, often at very slow transmission rates, is significantly reduced. Consideration of single-frequency systems for this application is viable because of the relatively small extent (< 50 km) of the entire network to be deployed. Unfortunately, the availability of research-quality software that can perform kinematic solutions on single-frequency data is limited. We have developed the BAKAR software employing a stochastic filter to analyze single-frequency GNSS data. The software can implement a range of stochastic models for time-dependent site position. In this presentation, we describe the BAKAR software, and discuss its strengths and weaknesses. On one hand, chief among the challenges we have encountered are determination of accurate prior positions, and bursts of polar ionospheric activity that impede cycle-slip detection, even over intersite distances as short as 10 km. On the other hand, use of a single-frequency observable is theoretically less sensitive to multipath and signal scattering. We will quantitatively assess these effects, and assess the accuracy of BAKAR in a range of situations and applications

The 18th International Symposium on Polar Sciences (ISPS): Milestones in Polar Research Collaboration, 22-24 May 2012, Jeju Island, Korea

The Mw 7.8 October 2010 Mentawai, Indonesia, earthquake was a “tsunami earthquake,” a rare type of earthquake that generates a tsunami much larger than expected based on the seismicmagnitude. It produced a locally devastating tsunami, with runup commonly in excess of 6 m. We examine this event using a combination of high-rate GPS data, from instruments located on the nearby islands, and a tsunami field survey. The GPS displacement time series are deficient in high-frequency energy, and show small coseismic displacements (16 m. Our modeling results show that the combination of the small GPS displacements and large tsunami can only be explained by high fault slip at very shallow depths, far from the islands and close to the oceanic trench. Inelastic uplift of trench sediments likely contributed to the size of the tsunami. Recent results for the 2011 Mw 9.0 Tohoko-Oki earthquake have also shown shallow fault slip, but the results from our study, which involves a smaller earthquake, provide much stronger constraints on how shallow the rupture can be, with the majority of slip for the Mentawai earthquake occurring at depths of

Laburpena: Ozeano Artikoa bankisa mehe batez estalita dago. Bankisa klima polarra taxutzen duen faktore garrantzitsuetako bat da, eta eragina izan dezake klima-sistema globalean ere. Garrantzi hori dela eta, beharrezkoa da Artikoko bankisa horren egoerari begiratzea eta hura ulertzea eta aurreikustea. Behaketek argi eta garbi erakutsi dute izotzaren hedadura eta lodiera murrizten ari direla eta izotz iraunkorra zena aldikako izotz ari dela bilakatzen. Inolako zalantza-izpirik gabe, Artikoko bankisa gainbehera nabarian dago. Bankisaren gainbehera hori ulertzeko, aldaketa horien kausa izan litezkeen prozesu termodinamiko eta dinamiko giltzarriak aztertu behar dira. Prozesuon artean daude, besteak beste, faktore fisikoak (adibidez, epeltzeko joerak), atmosferako eta ozeanoko zirkulazioan gertatutako aldaketak, ozeanoaren gainazalera iristen den eguzki-erradiazio handiagoa eta horri lotutako izotz-albedoaren berrelikadura. Gaur egungo ereduek aurreikusten dute mende hau amaitu baino lehen Ozeano Artikoa izotzik gabe geratuko dela udako urtze-garaiaren bukaeran. Behaketek, baina, erakusten dute bankisaren beherakada ez dela ereduek iragarritako abiaduran gertatzen ari, azkarrago baizik, eta agerian uzten dute ereduak hobetzeko premia. Artikoko bankisaren gainbeherak ondorio garrantzitsuak ditu Artikoko eta Lurreko klima-sistemetan, eta, gainera, gero eta erronka handiagoak ezartzen ditu alor sozioekonomikoan, politikoan eta ekologikoan, The Arctic Ocean is covered by a thin layer of sea ice. Sea ice plays an important role in determining Arctic climate, and it can also have an influence in the global climate system. This importance creates a need to observe, understand, and predict the state of the Arctic sea-ice cover. Observations unambiguously show that the ice extent is decreasing, the ice thickness is thinning, and that there is a shift from perennial ice to seasonal ice. It is beyond doubt that Arctic sea ice is in marked decline. Understanding the observed decline in sea ice involves examining the key thermodynamic and dynamic processes that can cause such changes. These include physical factors such as warming trends, shifts in atmospheric and oceanic circulation, increased solar radiation reaching the ocean surface, and the associated ice-albedo feedback. Current models predict an ice-free Arctic Ocean at the end of the Summer melt season by the end of this century, but observations reveal that the ongoing sea-ice decline is occurring more rapidly than model-based projections, highlighting the need of model improvements. A declining Arctic sea ice has important implications not only for both the Arctic and the global climate system, it also poses mounting socio-economic, political, and ecological challenges

I Encuentro de la Oceanografía Física Española (EOF), 13-15 de octubre 2010, Barcelona, Sea ice in the Arctic Ocean is undergoing rapid change, with sea ice extension reduced by 50% in the last 30 years, sea ice thickness plummeted by 40%, and models significantly underrepresenting this ongoing reduction, both temporally and spatially. To understand the processes at play and to improve models, it is essential to obtain high‐precision, long‐term observations of sea ice variation over pan‐Arctic spatial scales. As part of the “Arctic Ocean Sea‐ice and Ocean Circulation Changes Using Satellite Methods” (SATICE) Project, we are developing a polar GPS buoys capable of monitoring three‐dimensional motions of the sea ice surface with cm‐level accuracy and a temporal resolution of up to 1 Hz. Besides investigating sea ice dynamics, the strategic deployment of a network of these systems will allow us to improve tidal models and ocean dynamic topography in the Arctic Ocean, and to calibrate satellite missions focused on sea ice freeboard and mass balance estimates, such as Cryosat‐2. We will describe these systems and discuss how they will be used to address sea ice oceanography in the Arctic Ocean

The Ocean of Tomorrow Info Day, 9 September 2010, Brussels, Belgium

I Encuentro de la Oceanografía Física Española (EOF), 13-15 de octubre 2010, Barcelona, Sea ice cover is the most conspicuous feature of the Arctic Ocean. Changes in polar sea ice result from the complex interaction between the atmosphere, the ocean, and the cryosphere. The rapid changes observed most recently in Arctic Ocean sea ice illustrate the vulnerability of the Arctic system to global warming. Although some models suggest now that the summer Arctic could be ice free within our lifetime, models are still significantly underrepresenting the ongoing sea ice reduction, both in space and time. It is crucial to monitor these ice and ocean parameters to improve our understanding of the key processes that drive the Arctic climate change. The “Arctic Ocean Sea‐ice and Ocean Circulation Changes Using Satellite Methods” (SATICE) Project will estimate spatio‐temporal variations of ocean dynamic topography in the Arctic Ocean, ocean circulation, ocean tides, seaice freeboard heights, ice thickness and ice mass balance using in‐situ, novel highprecision Global Positioning System (GPS) observations of sea ice motions, satellitebased sea ice altimetry, and satellite gravity. We will present results pertaining to sea ice dynamics using high‐precision GPS observations obtained during two Arctic Ocean, SATICE experiments, in 2009 and 2010. We will also discuss how in situ high‐precision GPS observations, when combined with satellite remote sensing capabilities and modeling efforts, can contribute to improve our understanding of sea ice dynamics from small to Arctic basin spatio‐temporal scales

This paper analyzes the determinants of the interest rate of short-term unsecured loan inter-bank market (call) in Argentina. The results show that the heterogeneous nature of the entities, in terms of size and origin of ownership, impacts on the interest rate agreed. Other additional aspects, such as the linkages between entities and the degree of supply or demand concentration, also affect the cost of funding. The structure of the market and the repo rates established by the BCRA are also relevant. Finally, the interest rate reacts positively when banks have a higher demand for liquidity, due to both seasonality and episodes of reduction in deposits.

This paper analyzes the relationship between the quality of the commercial credit portfolio and diversification in the financial entities of Argentina during the period 1998-2006. To this effect, a database of the financial sector (banking and non-banking) is used, which allows to consider three potential dimensions of diversification: per productive sector, per province and per client. In addition to characterizing the financial entities’ diversification decisions during the period under analysis, which includes the severe economic and financial crisis of late 2001, the paper analyzes the determinants of the portfolio’s quality including the effect of diversification in the three dimensions stated above. The results indicate that, by controlling for the relevant variables, specialization improves the quality of the credit portfolio.

Fil: Covri Rivera, Daniele. Pontificia Universidad Católica Argentina. Facultad de Ciencias Económicas; Argentina Fil: García Cicco, Javier. Pontificia Universidad Católica Argentina. Facultad de Ciencias Económicas; Argentina Fil: Garegnani, María Lorena. Pontificia Universidad Católica Argentina. Facultad de Ciencias Económicas; Argentina Fil: Elosegui, Pedro. Pontificia Universidad Católica Argentina. Facultad de Ciencias Económicas; Argentina Resumen: Este trabajo de análisis consiste en aplicar la curva de Phillips para Ecuador en el periodo de la dolarización. Los datos fueron ajustados por un quiebre estructural presente al principio de la muestra y abarcan un horizonte temporal que va desde el primer trimestre 2003 hasta el cuarto trimestre 2015. Se contextualizaron las variables a la realidad ecuatoriana, pero el núcleo central está constituido por la estimación econométrica. La primera parte prevé regresiones MCO con expectativas adaptativas, y las brechas del desempleo y del producto fueron obtenidas mediante un filtro de Hodrick y Prescott. Después se repitió el proceso mediante variables instrumentales con expectativas racionales y al final se estimaron también tres modelos DSGE neokeynesianos. Se encontró que la curva de Phillips se valida únicamente con la brecha del desempleo, mientras que las expectativas de inflación resultan significativas únicamente en los modelos multiecuacionales que involucran la brecha del producto. En conclusión, políticas que quieran estimular el empleo tienen un efecto de alza en los precios, por lo que la situación puede justificarse en periodos recesivos para evitar una eventual deflación. Abstract: This paper consists of applying the Phillips curve for Ecuador in the period of dollarization. The data were adjusted for a structural break present at the beginning of the sample and cover a time horizon that goes from the first quarter of 2003 to the fourth quarter of 2015. The variables were contextualized to the Ecuadorian reality, but the core is based on the econometric estimation. The first part foresees OLS regressions with adaptive expectations, and the unemployment and output gaps were obtained using a Hodrick and Prescott filter. The process was then repeated using instrumental variables with rational expectations and at the end three New Keynesian DSGE models were also estimated. It was found that the Phillips curve is validated only with the unemployment gap, while inflation expectations are significant only in the multi-equation models that involve the output gap. In conclusion, policies that want to stimulate employment have a rising effect on prices, so this policy can be justified in recessive periods to avoid a possible deflation.

Memoria de tesis doctoral presentada por Julia de Juan Verger para optar al grado de Doctora en Ciencias de la Tierra por la Universitat de Barcelona (UB), realizada bajo la dirección del Dr. Pedro Elosegui Larrañeta de la Unitat de Tecnologia Marina (UTM-CSIC) y el Institut de Ciències de l'Espai (ICE-CSIC).-- 193 pages