Summary: | The north tip of the Trinity Peninsula, Antarctic Peninsula, has undergone changes in its ice-covered area and in the air temperature over the last three decades. Aiming to identify ice mass advances and retractions that occurred in the area, we conducted a survey of the changes in the ice front positions of 32 glaciers over 27 years (1988-2015). The study used 10 Landsat images to identify variations of glaciers fronts and compare them with variations in the mean annual air temperature. During this period, there was a decrease of approximately 50 km² in the regional ice fronts and an increase of ± 10 km², resulting in the loss of ± 40 km² of the ice-covered area at the north tip of the Trinity Peninsula (around ± 2.7% of the study area). In the period 1988–2000 this peninsula lost ± 25.1 km² of ice only in their fronts, from 2000 to 2006 the loss was of ± 12.2 km² and 5.0 km² from 2006 to 2011. The 2011–2015 period was the only one to show advances greater than retreats, with an area increase of ± 2.5 km² (± 0.16%). The mean air temperature data from the Antarctic base Esperanza (Argentina, 63°23'S 56°59'O), obtained from the READER portal, show an increase in the summer for the past 30 years (1985–2015), in the 1964–2014 period the increase was 1.45 °C. O extremo norte da Península Trinity, na Península Antártica, sofreu mudanças na sua área coberta de gelo e na temperatura do ar ao longo das últimas três décadas. Visando apontar os avanços e as retrações da massa de gelo ocorridas na área, realizamos um levantamento das variações da posição das frentes de 32 geleiras ao longo de 27 anos (1988–2015). O estudo usou 10 imagens Landsat para identificar as variações das frentes das geleiras e compará-las com as variações na temperatura média anual do ar. Nesse período, ocorreu o recuo de aproximadamente 50 km² nas frentes de gelo da região e um avanço de ±10 km², resultando na perda de ±40 km² da área coberta por gelo no extremo norte da Península Trinity (em torno de ±2,7 % da área de estudo). No período ...
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