Papers by Francisco Fernandoy
Hydrological Processes
The paper presents oxygen and hydrogen isotopes of 284 precipitation event samples systematically... more The paper presents oxygen and hydrogen isotopes of 284 precipitation event samples systematically collected in Irkutsk, in the Baikal region (southeast Siberia), between June 2011 and April 2017. This is the first high-resolution dataset of stable isotopes of precipitation from this poorly studied region of continental Asia, which has a high potential for isotope-based palaeoclimate research. The dataset revealed distinct seasonal variations: relatively high δ 18 O (up to −4‰) and δD (up to −40‰) values characterize summer air masses, and lighter isotope composition (−41‰ for δ 18 O and −322‰ for δD) is characteristic of winter precipitation. Our results show that air temperature mainly affects the isotope composition of precipitation, and no significant correlations were obtained for precipitation amount and relative humidity. A new temperature dependence was established for weighted mean monthly precipitation: +0.50‰/ C (r 2 = 0.83; p <.01; n = 55) for δ 18 O and +3.8‰/ C (r 2 = 0.83, p < 0.01; n = 55) for δD. Secondary fractionation processes (e.g., contribution of recycled moisture) were identified mainly in summer from low d excess. Backward trajectories assessed with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model indicate that precipitation with the lowest mean δ 18 O and δD values reaches Irkutsk in winter related to moisture transport from the Arctic. Precipitation originating from the west/southwest with the heaviest mean isotope composition reaches Irkutsk in summer, thus representing moisture transport across Eurasia. Generally, moisture transport from the west, that is, the Atlantic Ocean predominates throughout the year. A comparison of our new isotope dataset with simulation results using the European Centre/Hamburg version 5 (ECHAM5)-wiso climate model reveals a good agreement of variations in δ 18 O (r 2 = 0.87; p <.01; n = 55) and air temperature (r 2 = 0.99; p <.01; n = 71). However, the ECHAM5-wiso model fails to capture observed variations in d excess (r 2 = 0.14; p < 0.01; n = 55). This disagreement can be partly explained by a model deficit of capturing regional hydrological processes associated with secondary moisture supply in summer.
US Geological Survey and The National Academies, Aug 30, 2007
Palynoflora are reported from morainic deposits at several localities on Livingston Island, South... more Palynoflora are reported from morainic deposits at several localities on Livingston Island, South Shetland Islands. The palynomorphs observed include Pteridophyta, Pinophyta, Magnoliophyta and fungal spores. It is possible to distinguish two different palynological assemblages from the moraine deposits of Shirreff Cape, arbitrarily called Type A and B. Pteridophyta and Podocarpaceae dominate in the Type A association and in the Byers Peninsula palynoflora. Warm and humid conditions and an Early Cretaceous age are ...
This is the first report of a fossil flora from Hannah Point, Livingston Island, South Shetland I... more This is the first report of a fossil flora from Hannah Point, Livingston Island, South Shetland Islands, Antarctica. The fossiliferous content of an outcrop, located between two igneous rock units of Cretaceous age are mainly composed of leaf imprints and some fossil trunks. The leaf assemblage consists of 18 taxa of Pteridophyta, Pinophyta and one angiosperm. The plant assemblage can be compared to other Early Cretaceous floras from the South Shetland Islands, but several taxa have an evidently Late Cretaceous affinity. A ...
Mineralogical Magazine, 2013
The present work is a report on the geochemistry and petrology of the very low-grade alteration m... more The present work is a report on the geochemistry and petrology of the very low-grade alteration minerals developed in the volcanic successions from Punta Hannah (PH) and Shirreff Cape (SC), Livingston Island, Antarctica.
Stable Water Isotope Characterization of the Recent Hydrological System at the North Antarctic Peninsula and Its Relation with South America; Implication for Ice Core Interpretation
Epic3scar Open Science Conference Buenos Aires Argentina, 2010
Paleoflora mesozoica de Cabo Shirreff, isla Livingstone, Archipiélago Shetland del Sur, Antártica
Nuevo hallazgo de flora mesozoica en Cabo Shirreff, Isla Livingstone Archipiélago Shetland del Sur, Antártica
Aportes al conocimiento de la flora mesozoica de Cabo Shirreff, Isla Livingstone, Antártica chilena
Flora mesozoica en los depósitos morrénicos de Cabo Shirreff, Isla Livingston, Shetland del Sur, Península Antártica
Actas del 10º Congreso Geológico Chileno. CD-ROM. Resumen Expandido, 4pp. Universidad de Concepción. Concepción. Chile, 2004
The Cryosphere Discussions, 2011
In order to investigate the climate variability in the north Antarctic Peninsula region, this pap... more In order to investigate the climate variability in the north Antarctic Peninsula region, this paper focuses on the relationship between stable isotope content of precipitation and firn, and main meteorological variables (air temperature, relative humidity, sea surface temperature, and sea ice extent). Between 2008 and 2010, we collected precipitation samples and retrieved firn cores from several key sites in this region. We conclude that the deuterium excess oscillation represents a robust indicator of the meteorological variability on a seasonal to sub-seasonal scale. Low absolute deuterium excess values and the synchronous variation of both deuterium excess and air temperature imply that the evaporation of moisture occurs in the adjacent Southern Ocean. The δ18O-air temperature relationship is complicated and significant only at a (multi) seasonal scale. Backward trajectory calculations show that air-parcels arriving at the region during precipitation events predominantly originate at the South Pacific Ocean and Bellingshausen Sea. These investigations will be used as a calibration for on-going and future research in the area, suggesting that appropriate locations are located above 600 m a.s.l. We selected the Plateau Laclavere, Antarctic Peninsula as the most promising site for a deeper drilling campaign.
APECS-Chile: Shaping the Future of Polar Research from the South
ESTUDIO PRELIMINAR DEL METAMORFISMO DE BAJO GRADO EN ISLA REY JORGE, SHETLAND DEL SUR, ANTÁRTICA
antartida.gov.ar
V Simposio Argentino y I …, 2004
Preliminary study of the low-grade metamorphism in King George Island, South Shetlands, Antarctica
In order to gure out temporal trends of isotopic values, linear regressions were calculated for b... more In order to gure out temporal trends of isotopic values, linear regressions were calculated for both δD and δ O of all rn-cores ( gure b and c). The linear regression shows no signi cant tendency for those parameters at least since 1935. Due to the well know relation between isotope composition and air temperature, no warming trend at this location is inferred. This conclusion agrees with mean annual air temperature (MAAT) registry in the Neumayer Station: -16°C at 2 m level between 1982 and 2006. A mean annual temperature of -18°C to -20°C is estimated as the 10-meter borehole temperature at the core drilling locations. Firn-cores B-38 and B-39 are located at 690 and 655 meters of elevation and 81 km to the south-east and 110 km to the south-west of the German Station Neumayer, respectively. The mean annual δ O values -accumulation weighted-, of -20.58 ‰ for B-38 and -19.96‰ for B39, are close to the annual average value for fresh snow precipitation at the Neumayer Station (-20.49‰). Despite of the elevation di erence of approximately 600 m between Neumayer station and the drill sites, no signi cant altitude e ect is observed. The other two cores, located more towards the interior of the continent, have more negative δ O values: -24.23‰ for FB0702 (539 m a.s.l.) and -22.74‰ for FB0704 (760 m a.s.l.). Based on these observations, it is likely that the altitude e ects in this region start taking place at heights above 690 m a.s.l. The core FB0702 shows a di erence of -1.49 ‰ δ O in mean value with respect to FB0704, but having lower elevation. This discrepancy can not be explained neither by altitude nor by continentally e ects. A strong topographic in uence at this point, with an important input of precipitation of higher elevations coming from the south of Halvfarryggen is most like. This point will be later revisited. Deuterium analyses were carried out, as a rst step, with a resolution of 0.5 and 1.0 m. In general, the obtained values are in good agreement with the oxygen high resolution values, except for the core FB0702. But for this core the rst 4 meters were not yet measured and could cause this bias, due to the great variability at this coarse resolution.
Recent climate variability of the Antarctic Peninsula-isotopic characteristics and tele-connections of hydrological systems
Museo Nazionale dell'Antartide Felice Ippolito
Potential of the Stable Water Isotope Composition of Precipitation and Firn Cores as a Proxy for Climate Reconstruction at the Northern Antarctic …
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Papers by Francisco Fernandoy