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Surface energy balance on the Antarctic plateau as measured with an automatic weather station during 2014
Get PDFAWS data during 2014 collected at PANDA-N station, on the East Antarctica Plateau, are analysed. Net Short Wave Radiation (QSWR), net Long Wave Radiation (QLWR), sensible (QH), latent (QL) and subsurface or ground (QG) heat fluxes are computed. Annual averages for QSWR, QLWR, QH, QL and QG of 19.65, −49.16, 26.40, −0.77 and 3.86 W·m−2 were derived based on an albedo value of 0.8. QSWR and QH are the major sources of heat gain to the surface and QLWR is the major component of heat loss from the surface. An iterative method is used to estimate surface temperature in this paper; surface temperature of snow/ice is gradually increased or decreased, thereby changing longwave radiation, sensible, latent and subsurface heat fluxes, so that the net energy balance becomes zero. Mass loss due to sublimation at PANDA-N station for 2014 is estimated to be 12.18 mm w.e.·a−1; and mass gain due to water vapour deposition is estimated to be 3.58 mm w.e.·a−1. Thus the net mass loss due to sublimation/deposition is 8.6 mm w.e.·a−1. This study computes surface energy fluxes using a model, instead of direct measurements. Also there are missing data especially for wind speed, though 2 m air temperature data is almost continuously available throughout the year. The uncertainties of albedo, wind speed and turbulent fluxes cause the most probable error in monthly values of QLWR, QH, QL, QG and surface temperature of about ±4%, ±20%, ±50%, ±11% and ±0.74 K respectively
Paleobiological significance of the James Ross Basin
Get PDFThe extensive Late Mesozoic–Early Cenozoic sedimentary succession exposed within the James Ross Basin, Antarctica has huge potential to enhance paleobiological investigations into both the marine and terrestrial fossil records. In excess of 7 km in total thickness and spanning the Early Cretaceous (Aptian)–Late Eocene in age, it represents an invaluable high-latitude (~65°S) site for comparison with lower latitude, tropical ones in an essentially greenhouse world. The Early Cretaceous (Aptian–Albian) sequence is deep-water but there are indications of shallowing to inner shelf depths in both the Turonian and Coniacian stages. The first prolific shallow-water marine fauna occurs in the Santonian–Campanian Santa Marta Formation and this is followed by repeated occurrences through the later Campanian, Maastrichtian, Danian and Middle Eocene (Lutetian). In this study an attempt has been made to compare these Antarctic faunas directly with the well-known ones of the same age from the US Gulf Coast. Detailed comparisons made for three time slices, Late Maastrichtian, Danian and Middle Eocene, indicate that the Antarctic is characterised by both low taxonomic diversity and high levels of endemism. The James Ross Basin is providing important evidence to indicate that the highest southern latitudes have always been characterised by a distinctive temperate biota, even on a pre-glacial Earth. The roots of at least some elements of the modern Southern Ocean biota can be traced back to a Late Mesozoic–Early Cenozoic austral realm
Eocene Antarctica: a window into the earliest history of modern whales
Get PDFThe Eocene–Oligocene Southern Ocean is thought to have played a major role in cetacean evolution. Yet, fossils from its heart—Antarctica—are rare, and come almost exclusively from the Eocene La Meseta and Submeseta formations of Marambio (Seymour) Island. Here, we provide a summary and update of this crucial fossil assemblage, and discuss its relevance in the broader context of cetacean evolution. To date, Eocene specimens from Antarctica include basilosaurids, a group of archaic stem cetaceans that had already fully adapted to life in water; and the archaic toothed mysticete Llanocetus, the second oldest crown cetacean on record (ca. 34 Ma). This Eocene co-occurrence of stem and crown cetaceans is highly unusual, and otherwise only observed in Peru. Though related, at least some of the Antarctic species appear to be different from, and notably larger than their Peruvian counterparts, suggesting an early differentiation of the high latitude cetacean fauna
Newly established autonomous adaptive low-power instrument platform (AAL-PIP) chain on East Antarctic Plateau and operation
Get PDFAn autonomous adaptive low-power instrument platform (AAL-PIP) chain of six stations has been newly established on East Antarctic Plateau along the 40° geomagnetic meridian, to investigate interhemispheric geomagnetically conjugate current systems, waves, and other space weather phenomena in Polar Regions. These six stations, PG0 to PG5, which host low-power magnetometers (Fluxgate and Searchcoil), dual frequency GPS receivers, HF radio experiment, and run autonomously with solar power and two-way satellite communication, are designated at the geomagnetically conjugate (based on the International Geomagnetic Reference Field) locations of the West Greenland geomagnetic chain covering magnetic latitudes from 70° to 80°. We present the development, deployment, and operation of this chain, as well as the data collected by the chain and some preliminary scientific results showing evidence of interhemispheric asymmetries, which are important to better understand Solar Wind–Magnetosphere–Ionosphere (SWMI) coupling in Polar Regions. Recent investigations focus on magnetic impulse (MI) events, traveling convection vortices (TCVs), and ultra-low frequency (ULF) waves in the coupled southern and northern hemispheres
Role of lithology, weathering and precipitation on water chemistry of lakes from Larsemann Hills and Schirmacher Oasis of East Antarctica
Get PDFSchirmacher Oasis and Larsemann Hills areas represent two different periglacial environments of East Antarctica. Schirmacher Oasis is characterized by a vast stretch of ice-shelf in the north and East Antarctic Ice Sheet (EAIS) to its south. Whereas, in Larsemann Hills area the northern and north-western boundary is coastal area and EAIS in the southern part, exhibiting polar lowland between the marine and continental glacial ecosystems. Physico-chemical parameters of water samples from different lakes of both of these two distinct locations are quite contrasting and have indicated influence of lithology, weathering, evaporation and precipitation. The lake water chemistry in Larsemann Hills area is mainly governed by the lithology of the area while Schirmacher lakes exhibit influence of precipitation and rock composition. All major ions of lake waters indicate balanced ionic concentrations. The atmospheric precipitation has significantly modified the ionic distributions in the lakes and channels. Carbonation is the main proton supplying geochemical reactions involved in the rock weathering and this is an important mechanism which controls the hydrochemistry. The lake water hydrochemistry differs widely not only between two distant periglacial zones but also within a short distance of a single periglacial entity, indicating influence of territorial climate over hydrochemistry
Modified Rammsonde tests in layered compacted snow
Get PDFInvestigation of the physical and mechanical properties of snow has long been a topic of interest to researchers as the construction of compacted-snow runways in Antarctica developed. In an attempt to assess the strength of layered compacted seasonal snow, penetration tests using modified Rammsonde were conducted in Harbin, China in early 2018. Compared with previous models, the modified Rammsonde is lighter overall, with improved resolution; thus, it is more suitable for seasonal snow; the mechanical structure was adjusted, and the reading of depth data is more convenient. A total of 74 penetration tests were carried out and the results were analyzed both qualitatively and quantitatively. The results of these analyses demonstrated the applicability of the device, and revealed that several factors affect the cone penetrometer’s estimate of the strength of the layered compacted seasonal snow. Such factors include the confining pressure, penetration energy, and the snow material properties, particularly the compaction of the snow undergoing penetration. A linear relationship between the penetration pressure and snow density was also established. The effect of age hardening on the penetration pressure was studied and the microstructure of the snow particles was observed through a microscope. These analyses showed that the cone penetrometer and data processing methodology applied in this study enable a rapid estimate of strength in seasonal snow, and may be applied in Antarctica after further modification. This would provide a scientific basis for the design of China’s Antarctic ice sheet airport
Antarctic Paleontological Heritage: Late Cretaceous Paleogene vertebrates from Seymour (Marambio) Island, Antarctic Peninsula
Get PDFAntarctica has significant environmental, scientific, historic, and intrinsic values, all of which are worth protecting into the future. This continent has a discrete number of places of scientific interest that exhibit great potential as natural heritage sites; its geodiversity is of fundamental importance to scientific values of the continent, and the pursuit of geological and paleontological knowledge has had a strong influence on its historical values. Seymour Island was once called the ‘Rosetta Stone’ of Southern Hemisphere paleobiology, because this small island provides the most complete and richly fossiliferous Late Cretaceous–Paleogene sequence in Antarctica. In particular, fossil vertebrates form part of the evidence used in reconstructing the history of life on Antarctica. Paleontological heritage is considered a subset of geo-heritage that embodies both natural and historical components which has received only indirect recognition. Seymour Island is an outstanding paleontological area with high heritage value of its Late Cretaceous/Paleogene vertebrates and should be considered for geo-conservation and protection. This paper reviews vertebrate fossil occurrences and outcrops on Seymour Island and discusses some threats to these fossil sites
Arctic Connections - Scotland's Arctic Policy Framework
Get PDFFor centuries, Scotland and the Arctic have enjoyed close links that have had a lasting impact on our cultural, economic and social fabric. While most visible in our northernmost areas, these bonds are evident across the country and lie at the heart of our valued relationship with Arctic states. Scotland is among the Arctic region’s closest neighbours; we share many features and outlooks and have long looked to each other for inspiration, solutions
and ideas
The EDU-ARCTIC project: Interacting for STEM across countries and curricula
Get PDFEDU-ARCTIC is an open-schooling project, funded by the EU for the years 2016-2019 and managed by
scientists, nature educators and computer–technologists. The main aim is to attract young people (13-
20 years old) to the natural sciences. Further, to raise awareness of how everything in nature is
connected, and that STEM education therefore in part must be interdisciplinary across normal school
curricula. To achieve these goals, EDU-ARCTIC uses innovative online and freely accessible tools,
combined with nature expeditions.
Four main modules complement each other, but can also be used independently:
1) Webinars, during which scientists conduct online lessons about their own field of expertise. The
lessons come as packages with worksheets and online games. The lessons bring youth close to
scientists. They can ask questions about research and conditions of scientific works. It is also a valuable
tool for teachers to brush up their STEM knowledge and get inspiration for their own teaching.
2) Polarpedia, which is an online encyclopedia of scientific terms used in the webinars. The science is
kept easy-to-grasp, with the aim to stimulate the pupils’ curiosity to look for more information.
3) Monitoring system, which uses citizen science and the project’s own app to record observations of
meteorology and phenology. Observations are open for everybody to use in their own teachings.
4) Arctic Competitions, which is the module that has engaged the pupils the most. They submit their
idea for a science project in winter, work with the project over a few months and present it in spring as
an essay, a poster or a video. Teachers come up with innovative ways to fit this work into the normal
curricula. A few lucky winners get to join scientists on expeditions to polar research stations.
After 2.5 years, EDU-ARCTIC has engaged more than 1100 teachers and educators from 58 countries.
There is a language barrier for some teachers, and it is difficult to fit webinars into the school timetable.
However, the challenges are minor compared to the interdisciplinary success of having teachers meet
across countries and curricula. Here we illustrate this in detail by presenting a way of interdisciplinary
teaching (“the beauty of poetry and maths”) developed by one of the teachers in the project, Mr.
Francisco José Gómez Senent. Starting from a single poem published in Nature, it innovatively
combines mathematics, literature, history and linguistic competences. The teacher originally used it to
stimulate curiosity about the aesthetic criterion in science. Science is not only about facts! The approach
can be generalized to cover a wide range of curricula, and different teachers can use it in a team effort
across classes