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In this article, the authors tried to consider and structure the stages of development and creation of the “Yermak”, the world's first Arctic icebreaker, and analyzed the stages of preparation and the results of its first expeditions to explore the Arctic. Systematic analysis of historical sources and biographical material allowed to separate and comprehensively consider the conditions and prehistory for the development and creation of “Yermak” icebreaker. Also, the authors gave an assessment to the role of Vice Admiral Stepan Osypovych Makarov in those events, and analyzed the role of Sergei Yulyevich Witte, Dmitri Ivanovich Mendeleev and Pyotr Petrovich Semenov-Tian-Shansky in the preparation and implementation of the first Arctic expeditions of the “Yermak”icebreaker. In addition, the authors considered and analyzed the assessment of Vice Admiral Stepan Osypovych Makarov and his personal contribution to the results of the first Arctic expeditions of the “Yermak”icebreaker made by Baron Ferdinand von Wrangel. The first polar expeditions showed that the idea of Vice Admiral Stepan Osypovych Makarov about the icebreaker fleet was viable and required further development. It is shown that the results of the first Arctic expeditions made by “Yermak” allowed to significantly develop knowledge in various scientific fields of Arctic and Earth research, namely, topography, astronomy, meteorology, hydrology, geology, magnetism, zoology, and botany. The use of these methods and approaches to scientific research allowed to retrace the way of life and professional activity of Vice Admiral Stepan Osypovych Makarov’s systematically and critically evaluate the sources used, highlight the main points in the current state of studying the subject and the results of predecessors, specify the most promising directions of research, give a description of the previous works on this issue and clearly distinguish issues that have not yet been resolved.

Accelerated melting of ice in Polar Regions due to global warming increases freshwater input to coastal waters from marine terminating glaciers. Lack of measurements near the glacier terminus limits our knowledge of the mixing processes between freshwater and the underlying ocean. We present a low-cost (< € 3200) and lightweight (2.6 kg) drone-deployed, retrievable conductivity, temperature and depth (CTD) instrument for remote controlled (1 km) autonomous profiling in highly hazardous and remote areas. The instrument was deployed with a drone taking off from land and marine vessels to perform measurements near tidewater glaciers termini of the Greenland ice sheet. The free-flowing profiler is reusable due to a compact ballast based single-shot buoyancy engine and post-profiling pickup by drone. It can reach a depth of up to 250 m, and is equipped with low-cost sensors for conductivity, temperature, and depth measurements. During decent the profiler reaches a velocity of about 0.48 m/s, resulting in about 3.5 data points pr. m depth, but is designed to easily vary the velocity by changing buoyancy setup before deployment. Successful tests were conducted at marine terminating glaciers in Northeast Greenland in August 2021.

Major ions were analysed in firn and ice cores located at Fimbul Ice Shelf (FIS), Dronning Maud Land – DML, Antarctica. FIS is the largest ice shelf in the Haakon VII Sea, with an extent of approximately 36500km2. Three shallow firn cores (about 20m deep) were retrieved in different ice rises, Kupol Ciolkovskogo (KC), Kupol Moskovskij (KM), and Blåskimen Island (BI), while a 100m long core (S100) was drilled near the FIS edge. These sites are distributed over the entire FIS area so that they provide a variety of elevation (50–400ma.s.l.) and distance (3–42km) to the sea. Sea-salt species (mainly Na+ and Cl−) generally dominate the precipitation chemistry in the study region. We associate a significant sixfold increase in median sea-salt concentrations, observed in the S100 core after the 1950s, to an enhanced exposure of the S100 site to primary sea-salt aerosol due to a shorter distance from the S100 site to the ice front, and to enhanced sea-salt aerosol production from blowing salty snow over sea ice, most likely related to the calving of Trolltunga occurred during the 1960s. This increase in sea-salt concentrations is synchronous with a shift in non-sea-salt sulfate (nssSO42−) toward negative values, suggesting a possible contribution of fractionated aerosol to the sea-salt load in the S100 core most likely originating from salty snow found on sea ice. In contrast, there is no evidence of a significant contribution of fractionated sea salt to the ice-rises sites, where the signal would be most likely masked by the large inputs of biogenic sulfate estimated for these sites. In summary, these results suggest that the S100 core contains a sea-salt record dominated by the proximity of the site to the ocean, and processes of sea ice formation in the neighbouring waters. In contrast, the ice-rises firn cores register a larger-scale signal of atmospheric flow conditions and a less efficient transport of sea-salt aerosols to these sites. These findings are a contribution to the understanding of the mechanisms behind sea-salt aerosol production, transport and deposition at coastal Antarctic sites, and the improvement of the current Antarctic sea ice reconstructions based on sea-salt chemical proxies obtained from ice cores. Norwegian Polar Institute/[]//Noruega Universidad de Costa Rica/[805-B6-774]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones Geofísicas (CIGEFI) UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Física