Abstract This study investigated the chemical content of a shallow snow core (4.95 m) named TT 6, collected during a Brazilian traverse of the West Antarctic Ice Sheet in the 2014/2015 Austral summer. Stable isotope ratios (δD and δ18O) and ionic content, determined at the Centro Polar e Climático of the Federal University of Rio Grande do Sul (CPC/UFRGS), were used to date the core and reconstruct the climatic conditions at the site. The core represents approximately 11 years ± 6 months of precipitation, i.e., a mean net snow accumulation rate of 0.19 ± 0.02 m a-1 in water equivalent. Using the non-sea-salt sulfate values, we identified the 2011 Puyhue-Cordón (Chile) volcanic eruption signal, providing a reference horizon for dating. Anions represent 53.73% of the ionic content. We identified that 96.86% of calcium and 84.50% of sulfate are non-sea origin, while the acidic contribution is 25.62% H+. We observed high peaks in marine aerosols containing Na+, Cl-, and Mg2+ during winter, and results from the ERA5 global model (NOAA) indicated that El Niño events could influence Antarctic temperatures, facilitating the transport of marine aerosols to the continent. 4.95 495 4 95 (4.9 20142015 2014 2015 2014/201 summer δD δ18O δO δ O CPC/UFRGS, CPCUFRGS CPC/UFRGS , CPC UFRGS (CPC/UFRGS) site 1 precipitation ie i i.e. 019 0 19 0.1 002 02 0.0 a1 a- equivalent nonseasalt non sea salt values 201 PuyhueCordón Puyhue Cordón Chile (Chile signal dating 5373 53 73 53.73 9686 96 86 96.86 8450 84 50 84.50 nonsea origin 2562 25 62 25.62 H H+ Na Na+ Cl, Cl Cl- Mg2 Mg winter ERA NOAA (NOAA temperatures continent 4.9 49 9 (4. 2014201 2014/20 (CPC/UFRGS i.e 01 0. 00 20 537 5 7 53.7 968 8 96.8 845 84.5 256 2 25.6 4. (4 201420 2014/2 53. 96. 84. 25. ( 20142 2014/

Abstract A 22.48 m long ice core (BR-IC-4) was collected in the West Antarctic Ice Sheet (at 83°58’59.4” S, 80°07’01.4” W, 1,295 m above the sea level) during the Austral summer of 2004–2005, as a contribution to the International Trans-Antarctic Expedition program. The isotopic composition (δD and δ18O) of 599 samples, corresponding to the upper 12.98 m of the ice core, was determined by gas source mass spectrometry and cavity ring-down spectroscopy. Relative dating was based on the isotopic ratios and major ions (MS-, Na+, nssSO4 2-) and trace elements (Na, S, Sr) concentrations. The record covers approximately 13 years – from 1990 to 2003. The mean accumulation rate of 0.48 ± 0.09 m water equivalent per year (m eq H2O a1) is relatively high for the geographical area and possibly results from snowdrifting from near areas, as attested by ice glaze surfaces in other sites in the region. The stable isotope δD content varies between -367.90‰ and 256.30‰ (mean -314.42 ± 19.01‰); and δ18O ranges from -44.96‰ to 35.08‰ (mean -39.95 ± 2.05‰). Deuterium excess values (mean 3.70 ± 1.54‰) indicate episodic intense oceanic evaporation and high relative humidity in the moisture sources. 2248 22 48 22.4 BRIC4 BRIC BR IC 4 (BR-IC-4 at 83°5859.4 8358594 83°58 59.4 83 58 59 83°58’59.4 S 80°0701.4 8007014 80°07 01.4 80 07 01 80°07’01.4 W 1295 1 295 1,29 level 20042005 2004 2005 2004–2005 TransAntarctic Trans program δO δ O samples 1298 12 98 12.9 ringdown ring down spectroscopy MS, MS , (MS- Na Na+ nssSO 2 2- Na, (Na Sr concentrations 199 2003 048 0 0.4 009 09 0.0 HO H a1 areas region 367.90‰ 36790 367 90 -367.90 25630 256 30 256.30 314.42 31442 314 42 -314.4 19.01‰ 1901 19 19.01‰) 44.96‰ 4496 44 96 -44.96 3508 35 08 35.08 39.95 3995 39 95 -39.9 2.05‰. 205 2.05‰ . 05 2.05‰) 370 3 70 3.7 1.54‰ 154 54 sources 224 22. (BR-IC- 5859 83°5859. 835859 8358 83°5 594 59. 8 5 83°58’59. 0701 80°0701. 800701 8007 80°0 014 01. 80°07’01. 129 29 1,2 2004200 200 2004–200 9 12. (MS 04 0. 00 367.90 3679 36 -367.9 2563 25 256.3 314.4 3144 31 -314. 19.01 190 44.96 449 -44.9 350 35.0 39.9 399 -39. 20 2.05 37 7 3. 1.54 15 (BR-IC 585 83°5859 83585 835 83° 83°58’59 070 80°0701 80070 800 80° 80°07’01 1, 200420 2004–20 367.9 -367. 256. 314. -314 19.0 44.9 -44. 35. 39. -39 2.0 1.5 83°585 83°58’5 80°070 80°07’0 20042 2004–2 367. -367 -31 19. 44. -44 -3 2. 1. 83°58’ 80°07’ 2004– -36 -4 -

Abstract This article compares isotopic, ionic and climatic data from two firn cores from the West Antarctic Ice Sheet (WAIS). The IC-02 (88°01’21.3”S , 82°04’21.7”W) and the IC-05 (82°30’30.8”S , 79°28’02.7”W) closer to the coast. The IC-02 had 488 samples analyzed covering 14.58 meters depth while the IC-05 had 602 samples analyzed covering 19.73 meters depth. The time interval for both ice cores is 25 years ranging from 1978 to 2003. Sodium, sulfate and chloride were analyzed via ion chromatography using three DionexTM ionic chromatographers at the laboratories of Centro Polar e Climático (CPC) and at the Climate Change Institute. Stable isotope data was determined using cavity ring-down spectroscopy in a Picarro® spectrometer at the CPC. Annual accumulation was greater at IC-05 with an average of 0.35 m.eq.w.a-1 compared to 0.25 m.eq.w.a-1 at the IC-02. Stable isotope data was approximately 1.3 times more negative at the IC-02 which also presented higher d values. Na+ and Cl- were in higher concentrations at the IC-05 however Cl/Na was greater in the IC-02. The Cl excess was found to be derived from fractionation of sea salt aerosols and not related to volcanism. This work presents new insights regarding the chemical differences between ice cores. isotopic WAIS. WAIS . (WAIS) IC02 IC 02 IC-0 88°0121.3S 8801213S S 88°01 21.3 88 01 21 3 82°0421.7W 8204217W W 82°04 21.7 82 04 7 82°04’21.7”W IC05 05 82°3030.8S 8230308S 82°30 30.8 30 8 79°2802.7W 7928027W 79°28 02.7 79 28 79°28’02.7”W coast 48 1458 14 58 14.5 60 1973 19 73 19.7 2 197 2003 Sodium CPC (CPC Institute ringdown ring down Picarro 035 0 35 0.3 m.eq.w.a1 meqwa1 meqwa m.eq.w.a 1 m eq w m.eq.w.a- 025 0.2 IC02. 02. 13 1. values Na ClNa volcanism (WAIS IC0 IC- 0121 3S 8801 88°0 213 21. 0421 7W 8204 82°0 217 3030 8S 8230 82°3 308 30. 2802 7928 79°2 027 4 145 5 14. 6 19. 200 03 0. a1 012 880 88° 042 820 82° 303 823 280 792 79° 20

Abstract This study investigated the water isotopic content (δ18O, δD, d-excess) of the surface snow along a 995 km traverse over the West Antarctic Ice Sheet from the Möller Ice Stream – Institute Ice Stream to the upper reaches of the Pine Island Glacier drainage basin. The purpose of this study was to evaluate the climatic record preserved in the snow. We analyzed 92 surface samples (~0.15–0.20 m deep), retrieved during 2014/2015 austral summer from every ~10 km along the traverse route, using the laser spectroscopy technique. We computed the isotopic-geographical characteristics and spatial co-isotopic empirical relationships and compared the isotopic results with the tropospheric mean annual temperature and air mass trajectories. Our isotopic results were sensitive to capturing the well-known climatic asymmetry between the Amundsen-Bellingshausen Sea (ABS; which receives more influence from warmer (oceanic) air masses) and Weddell Sea (WS; more influenced by colder (continental) air masses) sectors. Further, the spatial distribution of δs and d-excess and the co-isotopic relationships reflect two preferential fractionation paths: one from the coast of the ABS sector to the WS sector, and another from the coast of the WS sector to the inland. The Pacific Ocean is confirmed as the primary source of moisture.

O objetivo do trabalho foi correlacionar as características ecográficas dos nódulos tireóideos aos achados citológicos, para determinar a importância da ultra-sonografia na doença nodular da tireóide. Foram realizadas punções aspirativas por agulha fina orientadas por ultra-som, após avaliação e classificação ecográfica de 436 nódulos. Obteve-se celularidade adequada para análise em 401 nódulos (92%), procedendo-se à correlação ecográfico/citológica. A classificação utilizada permitiu distribuir as características ecográficas de acordo com o risco de malignidade, identificando nódulos Grau III císticos com foco sólido (citologia positiva em 23,8%) e sólidos hipoecóicos (40%) como suspeitos e os Grau IV (95,2%) como altamente suspeitos. Os nódulos Grau II sólidos iso e hiperecóicos (5%) e mistos (1,9%), em acordo com a literatura, foram considerados provavelmente benignos. O ultra-som forneceu auxílio importante à avaliação clínica e determinação da conduta a ser tomada, devendo fazer parte dos protocolos para avaliação inicial e acompanhamento da doença nodular da tireóide.

The goal of this work is to determine the role of ultrasonography in the evaluation of thyroid nodules correlating its echographic characteristics to cytological findings. Ultrasound-guided fine-needle aspiration biopsies were performed after echographic evaluation and classification of 436 nodules. Adequate samples for analysis were obtained in 401 nodules (92%), and echographic/cytological correlation was assessed. The echographic classification allows, through the different characteristics of the thyroid nodules, identifying cystic nodules with solid projections (positive cytology in 23,8%) and solid hipoechoic (40%) considered suspicious (Grade III) and highly suspicious (Grade IV - 95,2%) for malignancy. Iso and hyperechoic solid nodules (5%) and mixed nodules (1,9%) classified as Grade II, in agreement with the literature, are considered to be probably benign. Thyroid ultrasound proved to be an important aid to clinical evaluation and management; and should therefore be part of the initial evaluation and follow up of thyroid nodules.