Northern Polar Cap Research Articles

Satellite images in the new Atlas «Russian Arctic»

The increasing interest in the Arctic promotes appearance of new cartographic products to provide information for the primary tasks of this region development. So, several atlases of the Arctic have been already published. At the initiative and with the financial support from the oil and gas industry, a new Atlas «Russian Arctic» is being prepared for publication, in which considerable attention is given to the environmental aspects of the development of the North with account for conditions of changing climate. Unlike previous atlases, this Atlas contains thematic sets of satellite images reflecting changes in the natural environment, in particular, different types of natural ice under conditions of warming. The space part of the Atlas developed by the authors of this article covers a number of subjects. Thus, the decrease in the area of sea ice is illustrated by the materials of shooting from the space of the Northern polar cap for the period of the largest reduction in the area. Images made in different time fix retreating of the shores, composed of underground ice, being the result of the processes of thermal abrasion, thermal erosion and thermal denudation. Complicated ice conditions of navigation in the Ob Bay and characteristics of the Arctic rivers mouths are presented by pictures of tidal estuaries of the rivers Mezen and Kuloi. Images of ice jams at the mouth of the Northern Dvina River and materials of space monitoring of measures for liquidation of them are also given in the Atlas. Special attention is given to forms of permafrost relief, which are well displayed in high-resolution images. They show a polygonal micro-relief of different types and stages of development of them, as well as frost mounds, dales, and thermo-erosion forms. Formation of aufeises (naleds), thermokarst lakes, and craters of gas outbursts is also shown. The wildlife of the Arctic is represented in the Atlas as well. The pictures present a visual image of different types of tundra. The influence of warming on vegetation development is well reflected in the photo map of the dynamics of the vegetation index for 2000-2009, showing the growth of phytomass in the European North. The Atlas contains unique materials of satellite monitoring of Arctic mammals - walruses and seals. The impact of using mineral resources on the vulnerable nature of the Arctic is shown in the Khibiny region. Prominent examples of the vegetation degradation in the areas of Norilsk and Monchegorsk cities are given, where technogenic wastelands have been formed under the sulfuric acid fumes of the copper-nickel plants.

Linear time-series modeling of the GNSS based TEC variations over Southwest Japan during 2011–2018 and comparison against ARMA and GIM models

A significant amount of research has been conducted in Southwest (SW) Japan on climate modeling, disaster management, earthquake prediction, precise positioning, datum definition, and reference frames. However, there is substantial scope for numerical modeling and forecasting of ionospheric Total Electron Content (TEC) variations over the region, which would be beneficial for further communication and navigation purposes. Therefore, in this study we examined spatio-temporal ionospheric TEC variations using long-term Global Navigation Satellite System (GNSS) measurements from 01 January, 2011 to 31 December, 2018 through a modified Linear Time-series Model (LTM) and substantiated our findings by comparing them with those of the existing empirical Global Ionospheric Map (GIM) and Auto-Regressive Moving Average (ARMA) methods. We analyzed TEC variations at 10 permanent stations covering three districts of SW Japan, which mainly include the Kyushu district and parts of the Chugoku and Shikoku districts. To determine the performance of the LTM, the geomagnetic (Northern Polar Cap (PCN) and Disturbance (Dst)) indices were included, together with the additional solar and planetary geomagnetic disturbance indices (F10.7 and Ap). Our comparison results show that the Root Mean Square Error (RMSE) values in terms of TEC units (TECUs) between the observed and the TEC predicted by the LTM vary from 1.57 to 1.66, which are better than those between the observed and the TEC predicted by the ARMA (1.84–1.93) and the GIM (9.67–9.84) TEC models. An analysis of the results emphasizes the superior performance of the LTM over the other models in terms of its discriminability of temporal, as well as spatial, components.

The duration and magnitude of Cretaceous cool events: Evidence from the northern high latitudes

AbstractThe Early Cretaceous (145–100 Ma) was characterized by long-term greenhouse climates, with a reduced equatorial to polar temperature gradient, although an increasingly large body of evidence suggests that this period was punctuated by episodic global “cold snaps.” Understanding climate dynamics during this high-atmospheric CO2 period of Earth’s history may have significant impact on how we understand climatic feedbacks and predict future global climate changes under an anthropogenically-driven high-pCO2 atmosphere. This study utilizes facies analysis to constrain the paleobathymetry of Lower Cretaceous glendonites—a pseudomorph after ikaite, a mineral that forms naturally at 7 °C or lower—from two paleo-high-latitude (60–70°N) sites in Svalbard, Arctic Norway, to infer global climatic changes during the Early Cretaceous. The original ikaite formed in the offshore transition zone of a shallow marine shelf at water depths of <100 m, suggesting mean annual water temperatures of ≤7 °C at these depths at 60–70°N. We correlate glendonite-bearing horizons from Lower Cretaceous successions around the globe using carbon isotope stratigraphy, in conjunction with the pre-existing biostratigraphic framework, in order to infer northern hemispheric to global climatic cooling. A distinct interval of glendonites in the Northern Hemisphere, from sites >60°N, spans the late Berriasian to earliest Barremian (at least 8.6 m.y.), significantly prolonging the duration of the previously hypothesized Valanginian cold snap (associated with the “Weissert Event”). Widespread glendonites occur again in late Aptian and extend to the early Albian, in both hemispheres, corroborating other proxy evidence for late Aptian cooling. The glendonites from Svalbard suggest that Cretaceous cold episodes were characterized with high latitude (>60°N) shallow water temperatures that are consistent with the existence of a small northern polar ice cap at this time.

SuperDARN Radar‐Derived HF Radio Attenuation During the September 2017 Solar Proton Events

AbstractTwo solar proton events in September 2017 had a significant impact on the operation of the Super Dual Auroral Radar Network (SuperDARN), a global network of high‐frequency (HF) radars designed for observing F region ionospheric plasma convection. Strong polar cap absorption caused near‐total loss of radar backscatter, which prevented the primary SuperDARN data products from being determined for a period of several days. During this interval, the high‐latitude and polar cap radars measured unusually low levels of background atmospheric radio noise. We demonstrate that these background noise measurements can be used to observe the spatial and temporal evolution of the polar cap absorption region, using an approach similar to riometry. We find that the temporal evolution of the SuperDARN radar‐derived HF attenuation closely follows that of the cosmic noise absorption measured by a riometer. Attenuation of the atmospheric noise up to 10 dB at 12 MHz is measured within the northern polar cap, and up to 14 dB in the southern polar cap, which is consistent with the observed backscatter loss. Additionally, periods of enhanced attenuation lasting 2–4 hr are detected by the midlatitude radars in response to M‐ and X‐class solar flares. Our results demonstrate that SuperDARN's routine measurements of atmospheric radio noise can be used to monitor 8‐ to 20‐MHz radio attenuation from middle to polar latitudes, which may be used to supplement riometer data and also to investigate the causes of SuperDARN backscatter loss during space weather events.

Ionospheric Effects of the Sudden Stratospheric Warming in 2009: Results of Simulation with the First Version of the EAGLE Model

In this paper, we discuss perturbations in neutral temperature, total electron content (TEC), and critical frequency of the maximum of the F2 layer (foF2) during the sudden stratospheric warming in January 2009. The calculations were performed using the first version of the EAGLE (Entire Atmosphere Global Model), which is a combination of the models of the low–middle atmosphere (HAMMONIA) and the upper atmosphere (GSM TIP). The EAGLE reproduces observed stratospheric warming and related mesospheric cooling in the northern polar cap in January 2009. At thermospheric altitudes, the neutral temperature perturbations have a quasi-wave character with a wavelength of ∼40 km in the vertical direction. Our results indicate that the HAMMONIA model should be used in the EAGLE instead of the GSM TIP model for the neutral temperature calculations in the altitude region from 80 to 120 km. It is shown that the obtained model foF2 and TEC perturbations are mainly related to seasonal variations. The most-pronounced perturbations in the ionospheric electron density due to stratospheric warming are formed near the equator and are basically negative. Our analysis of the neutral temperature and electron density perturbations made it possible to conclude that the dependence of ionospheric parameters on seasonal changes in solar zenith angle is stronger than for the thermosphere parameters.

Uranus's northern polar cap in 2014.

In October and November 2014, spectra covering the 1.436 - 1.863-μm wavelength range from the SINFONI Integral Field Unit Spectrometer on the Very Large Telescope showed the presence of a vast bright North polar cap on Uranus, extending northward from about 40°N and at all longitudes observed. The feature, first detected in August 2014 from Keck telescope images, has a morphology very similar to the southern polar cap that was seen to fade before the 2007 equinox. At strong methane-absorbing wavelengths (for which only the high troposphere or stratosphere is sampled) the feature is not visible, indicating that it is not a stratospheric phenomenon. We show that the observed northern bright polar cap results mainly from a decrease in the tropospheric methane mixing ratio, rather than from a possible latitudinal variation of the optical properties or abundance of aerosol, implying an increase in polar downwelling near the tropopause level.

Magnetospheric access for solar protons during the January 2005 SEP event

The early phase of the extraordinary solar energetic particle 20 January, 2005 event having the highest peak flux of any SEP in the past 50 years of protons with energies > 100 MeV is studied. Solar energetic particles (>16 MeV) entry to the Earth’s magnetosphere on January 20, 2005 under northward interplanetary magnetic field conditions is considered based on multi-satellite data analysis and magnetic field simulation. Solar wind parameters and interplanetary magnetic field data, as well as calculations in terms of the A2000 magnetospheric magnetic field model were used to specify conditions in the Earth’s environment corresponding to solar proton event. It was shown that during the early phase of the event energetic particle penetration into the magnetosphere took place in the regions on the magnetopause where the magnetospheric and interplanetary magnetic field vectors are parallel. Complex analysis of the experimental data on particle fluxes in the interplanetary medium (data from ACE spacecraft) and on low-altitude (POES) and geosynchronous (GOES) orbits inside the Earth’s magnetosphere show two regions on the magnetopause responsible for particle access to the magnetosphere: the near equatorial day-side region and open field lines window at the high-latitude magnetospheric boundary. Calculations in terms of A2000 magnetospheric magnetic field model and comparison with SuperDARN images support the link between high-latitude solar energetic particle precipitations and the region at the magnetopause where the magnetospheric field is coupled with northward IMF, allowing solar particles entrance into the magnetosphere and access to the northern polar cap.

Dynamics of ionospheric disturbances during the 17–19 March 2015 geomagnetic storm over East Asia

Based on vertical sounding data from nine ionosondes located at 19–66°N, 100–130°E we investigated the latitude-temporal dynamics of ionospheric disturbances during the 17–19 March 2015 severe two-step geomagnetic storm, and compared it with temporal dynamics of total electron content (TEC) profiles along 120°E. The phenomena that accompanied the main and early recovery storm phases were in particular focused on in this study. The distinct storm-related ionospheric disturbances began 2.5, 4 and 5h after onset of the storm main phase at subauroral, middle and low latitudes, respectively. To clarify the main mechanisms causing the disturbances at different latitudes we compared the changes in ionospheric parameters and TEC profiles with changes in the northern polar cap index and geomagnetic field in the vicinity of 120°E. The equatorward shift of the main ionospheric trough (MIT) and diffuse precipitations zone accompanied by an increase in precipitating particle flux was found to have a substantial influence on the subauroral ionosphere during the main and early recovery phases. The thermosphere Joule heating due to westward and polarized jets led to an increase in neutral wind velocity and generation of disturbed dynamo electric field. The strengthened wind was the main reason of the positive ionospheric disturbance observed at middle latitudes in the evening on 17 March. The further enhancement of magnetospheric convection caused the displacement of MIT and its associated negative ionospheric disturbance to middle latitudes. At low latitudes superposition of prompt penetration and disturbed dynamo electric fields play the decisive role in the ionosphere behavior till the end of the early recovery phase.

Interplay of solar wind parameters and physical mechanisms producing the saturation of the cross polar cap potential

AbstractThe nonlinear response of the cross polar cap potential (CPCP) to solar wind driving electric field is a well‐known phenomenon. The reasons behind this saturation, however, are still under debate. We have performed a statistical study of the coupling efficiency between the solar wind and the northern polar cap index (PCN). PCN is used as a proxy for the CPCP. Our main focus is in quantifying how the solar wind dynamic pressure alters the efficiency. We show that the saturation of PCN occurs both during low and moderate upstream MA conditions. We also show that the increasing dynamic pressure is associated with increasing PCN. In addition, we find that the coupling is different depending on which parameter, the velocity or the magnetic field, increases the solar wind driving electric field: the higher the velocity the higher the coupling efficiency.

Remnant Massifs of Layered Deposits at High Northern Latitudes of Mars

Ice deposits of the permanent northern polar cap of Mars exhibit a clearly expressed layered structure connected with consecutive accumulation of a solid phase of H2O (ice) with different impurity fractions of dust. The observed structure of the northern polar cap deposits is direct evidence of the uneven accumulation of ice associated with climate variations on Mars over a long period of time. Outside the boundaries of the present northern polar cap, there are isolated remnant massifs of bright deposits with a clearly distinguishable layered structure. In this paper, we analyze the morphology, spatial distribution, and material composition of remnant massifs within the latitude belt of 60°–85°. The similarity in the structure and material composition found in the remnant massifs and the layered deposits of the northern polar cap of Mars apparently suggests that these formations were genetically connected in the past climatic epochs.

Observed glacier and volatile distribution on Pluto from atmosphere–topography processes

Pluto has a variety of surface frosts and landforms as well as a complex atmosphere. There is ongoing geological activity related to the massive Sputnik Planitia glacier, mostly made of nitrogen (N2) ice mixed with solid carbon monoxide and methane, covering the 4-kilometre-deep, 1,000-kilometre-wide basin of Sputnik Planitia near the anti-Charon point. The glacier has been suggested to arise from a source region connected to the deep interior, or from a sink collecting the volatiles released planetwide. Thin deposits of N2 frost, however, were also detected at mid-northern latitudes and methane ice was observed to cover most of Pluto except for the darker, frost-free equatorial regions. Here we report numerical simulations of the evolution of N2, methane and carbon monoxide on Pluto over thousands of years. The model predicts N2 ice accumulation in the deepest low-latitude basin and the threefold increase in atmospheric pressure that has been observed to occur since 1988. This points to atmospheric-topographic processes as the origin of Sputnik Planitia's N2 glacier. The same simulations also reproduce the observed quantities of volatiles in the atmosphere and show frosts of methane, and sometimes N2, that seasonally cover the mid- and high latitudes, explaining the bright northern polar cap reported in the 1990s and the observed ice distribution in 2015. The model also predicts that most of these seasonal frosts should disappear in the next decade.

The formation of Charon's red poles from seasonally cold-trapped volatiles.

A unique feature of Pluto's large satellite Charon is its dark red northern polar cap. Similar colours on Pluto's surface have been attributed to tholin-like organic macromolecules produced by energetic radiation processing of hydrocarbons. The polar location on Charon implicates the temperature extremes that result from Charon's high obliquity and long seasons in the production of this material. The escape of Pluto's atmosphere provides a potential feedstock for a complex chemistry. Gas from Pluto that is transiently cold-trapped and processed at Charon's winter pole was proposed as an explanation for the dark coloration on the basis of an image of Charon's northern hemisphere, but not modelled quantitatively. Here we report images of the southern hemisphere illuminated by Pluto-shine and also images taken during the approach phase that show the northern polar cap over a range of longitudes. We model the surface thermal environment on Charon and the supply and temporary cold-trapping of material escaping from Pluto, as well as the photolytic processing of this material into more complex and less volatile molecules while cold-trapped. The model results are consistent with the proposed mechanism for producing the observed colour pattern on Charon.

Thermosphere variation at different altitudes over the northern polar cap during magnetic storms

In this study, we report observations and simulation results of heated neutrals at various altitudes inside the polar cap during two magnetic storms in January 2005. The Poynting flux measurements from the Defense Meteorological Satellite Program (DMSP) satellites show enhanced energy input in the polar cap during the storm main phase, which is underestimated in the TIE-GCM simulation. Neutral temperature measurements at 250km from the ground-based Fabry-Perot Interferometer (FPI) at Resolute Bay are presented, along with the neutral density observations at 360km and 470km from Challenging Minisatellite Payload (CHAMP) and the Gravity Recovery and Climate Experiment (GRACE) satellites, respectively. These data have been analyzed to demonstrate the altitudinal dependence of neutral response to the storm energy input. By comparing the TIE-GCM simulation results and the observations, we demonstrate that Poynting fluxes as well as the thermosphere response were underestimated in the model. The simulated neutral temperature at Resolute Bay increases by approximately 260° and 280°K for the two events, respectively, much lower than the observed temperature enhancements of 750° and 900°K. Neutral density enhancements with more than 30% increase over the background density were also observed at polar latitudes, with no clear distinction between the auroral zone and polar cap. All measurements indicate enhancements at high latitudes poleward of 80° magnetic latitude (MLAT) implying that substantial heating can occur within the polar cap during storms.

Response of northern winter polar cap to auroral substorms

AbstractThe three‐phase substorm sequence has been generally accepted and is often tied to the Dungey cycle. Although previous studies have mostly agreed on the increase and decrease in the polar cap area during an episode of substorm, there are disparate views on when the polar cap starts to contract relative to substorm onset. Here we address this conflict using high‐resolution (~1–3 min) snapshot global auroral images from the ultraviolet imager on board the Polar spacecraft. On the basis of 28 auroral substorm events, all observed in the Northern Hemispheric winter, it is found that the polar cap inflated prior to onset in all events and it attained the largest area ~6 min prior to the substorm expansion phase onset, while the dayside polar cap area remained steady around the onset. The onset of nightside polar cap deflation is found to be attributed to intensifications of aurora on the poleward edge of the nightside oval, mostly in the midnight sector. Although this result supports the loading‐unloading and reconnection substorm models, it is not clear if the initial polar cap deflation and the substorm expansion are parts of the same process.

MESSENGER observations of solar energetic electrons within Mercury's magnetosphere

AbstractDuring solar energetic particle (SEP) events, the inner heliosphere is bathed in MeV electrons. Through magnetic reconnection, these relativistic electrons can enter the magnetosphere of Mercury, nearly instantaneously filling the regions of open field lines with precipitating particles. With energies sufficient to penetrate solid aluminum shielding more than 1 mm thick, these electrons were observable by a number of sensors on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Because of its thin shielding, frequent sampling, and continuous temporal coverage, the Fast Imaging Plasma Spectrometer provided by far the most sensitive measurements of MeV electrons of all MESSENGER sensors. Sharp changes in energetic electron flux coincided with topological boundaries in the magnetosphere, including the magnetopause, polar cap, and central plasma sheet. Precipitating electrons with fluxes equal to ~40% of their corresponding upstream levels were measured over the entire polar cap, demonstrating that electron space weathering of Mercury's surface is not limited to the cusp region. We use these distinct precipitation signatures acquired over 33 orbits during 11 SEP events to map the full extent of Mercury's northern polar cap. We confirm a highly asymmetric polar cap, for which the dayside and nightside boundary latitudes range over ~50–70°N and ~30–60°N, respectively. These latitudinal ranges are consistent with average models of Mercury's magnetic field but exhibit a large variability indicative of active dayside and nightside magnetic reconnection processes. Finally, we observed enhanced electron fluxes within the central plasma sheet. Although these particles cannot form a stable ring current around the planet, their motion results in an apparent trapped electron population at low latitudes in the magnetotail.

FAINT LUMINESCENT RING OVER SATURN’S POLAR HEXAGON

Springtime insolation is presently advancing across Saturn's north polar region. Early solar radiation scattered through the gaseous giant's atmosphere gives a unique opportunity to sound the atmospheric structure at its upper troposphere/lower stratosphere at high latitudes. Here, we report the detection of a tenuous bright structure in Saturn's northern polar cap corresponding to the hexagon equatorward boundary, observed by Cassini Visual and Infrared Mapping Spectrometer on 2013 June. The structure is spectrally characterized by an anomalously enhanced intensity in the 3610–3730 nm wavelength range and near 2500 nm, pertaining to relatively low opacity windows between strong methane absorption bands. Our first results suggest that a strong forward scattering by tropospheric clouds, higher in respect to the surrounding cloud deck, can be responsible for the enhanced intensity of the feature. This can be consistent with the atmospheric dynamics associated with the jet stream embedded in the polar hexagon. Further investigations at higher spectral resolution are needed to better assess the vertical distribution and microphysics of the clouds in this interesting region.

Evolution of Mars' northern polar seasonal CO2deposits: Variations in surface brightness and bulk density

Small-scale variations of seasonal ice are explored at different geomorphic units on the Northern Polar Seasonal Cap (NPSC). We use seasonal rock shadow measurements, combined with visible and thermal observations, to calculate density over time. The coupling of volume density and albedo allows us to determine the microphysical state of the seasonal CO2 ice. We find two distinct end-members across the NPSC: (1) Snow deposits may anneal to form an overlying slab layer that fractures. These low-density deposits maintain relatively constant densities over springtime. (2) Porous slab deposits likely anneal rapidly in early spring and fracture in late spring. These high-density deposits dramatically increase in density over time. The end-members appear to be correlated with latitude.

Seasonal variation of the HDO/H2O ratio in the atmosphere of Mars at the middle of northern spring and beginning of northern summer

We present the seasonal variation of the HDO/H2O ratio caused by sublimation–condensation processes in a global view of the martian water cycle. The HDO/H2O ratio was retrieved from ground-based observations using high-dispersion echelle spectroscopy of the Infrared Camera and Spectrograph (IRCS) of the Subaru telescope. Coordinated joint observations were made by the Planetary Fourier Spectrometer (PFS) onboard Mars Express (MEX). The observations were performed during the middle of northern spring (Ls=52°) and at the beginning of summer (Ls=96°) in Mars Year 31. The retrieved latitudinal mean HDO/H2O ratios are 4.1±1.4 (Ls=52°) and 4.4±1.0 (Ls=96°) times larger than the terrestrial Vienna Standard Mean Ocean Water (VSMOW). The HDO/H2O ratio shows a large seasonal variation at high latitudes. The HDO/H2O ratio significantly increases from 2.4±0.6wrt VSMOW at Ls=52° to 5.5±1.1wrt VSMOW at Ls=96° over the latitude range between 70°N and 80°N. This can be explained by preferential condensation of HDO vapor during the northern fall, winter, and spring and sublimation of the seasonal polar cap in the northern summer. In addition, we investigated the geographical distribution of the HDO/H2O ratio over low latitudes at the northern spring in the longitudinal range between 220°W and 360°W, including different local times from 10h to 17h. We found the HDO/H2O ratio has no significant variation (5.1±1.2wrt VSMOW) over the entire range. Our observations suggest that the HDO/H2O distribution in the northern spring and summer seasons is mainly controlled by condensation-induced fractionation between the seasonal northern polar cap and the atmosphere.

Ground-based observations of Saturn’s auroral ionosphere over three days: Trends in [formula omitted] temperature, density and emission with Saturn local time and planetary period oscillation

On 19–21 April 2013, the ground-based 10-m W.M. Keck II telescope was used to simultaneously measure H3+ emissions from four regions of Saturn’s auroral ionosphere: (1) the northern noon region of the main auroral oval; (2) the northern midnight main oval; (3) the northern polar cap and (4) the southern noon main oval. The H3+ emission from these regions was captured in the form of high resolution spectral images as the planet rotated. The results herein contain twenty-three H3+ temperatures, column densities and total emissions located in the aforementioned regions – ninety-two data points in total, spread over timescales of both hours and days. Thermospheric temperatures in the spring-time northern main oval are found to be cooler than their autumn-time southern counterparts by tens of K, consistent with the hypothesis that the total thermospheric heating rate is inversely proportional to magnetic field strength. The main oval H3+ density and emission is lower at northern midnight than it is at noon, in agreement with a nearby peak in the electron influx in the post-dawn sector and a minimum flux at midnight. Finally, when arranging the northern main oval H3+ parameters as a function of the oscillation period seen in Saturn’s magnetic field – the planetary period oscillation (PPO) phase – we see a large peak in H3+ density and emission at ∼115° northern phase, with a full-width at half-maximum (FWHM) of ∼44°. This seems to indicate that the influx of electrons associated with the PPO phase at 90° is responsible at least in part for the behavior of all H3+ parameters. A combination of the H3+ production and loss timescales and the ±10° uncertainty in the location of a given PPO phase are likely, at least in part, to be responsible for the observed peaks in H3+ density and emission occurring at a later time than the peak precipitation expected at 90° PPO phase.

Hydrolysed polar terrain ice aerobot mission platform

HYPATIA is a proposed mission that would demonstrate the use of planetary balloon and water electrolysis technology on the Martian northern polar cap. The combination of both technologies allows a small science payload to be landed repeatedly and carried across the polar terrain. HYPATIA consists of a small gondola under a metallised Mylar balloon filled with hydrogen from the polar ice. This paper details the mission objectives and the science requirements. It describes the overall mission design and the science payload of the balloon vehicle.