scholarly journals SIMULATION OF ELECTROMAGNETIC SOUNDING SIGNALS FROM THE ARCTIC ICE SURFACE

2019 ◽  
Vol 2 (2) ◽  
pp. 116-123
Author(s):  
Polina Osipova ◽  
Vladimir Mogilatov ◽  
Arkadiy Zlobinskiy
Keyword(s):  
Born Approximation ◽  
Three Dimensional ◽  
Arctic Region ◽  
The Arctic ◽  
Electromagnetic Sounding ◽  
Three Dimensional Modeling ◽  
Ice Surface ◽  
Dimensional Modeling ◽  
Arctic Ice ◽  
The Arctic Region

Electromagnetic sounding of the Arctic region is hampered by the influence of the conductive layer of seawater. As part of the RSF project, it is proposed to use a circular electrical dipole (CED) to excite the field. Installation should be placed on drifting ice. This technique requires three-dimensional modeling for which there are complex algorithms. The paper proposes an approach using the Born approximation to simplify the implementation of three-dimensional modeling of the electromagnetic sounding signal using CED.

Simulation of electromagnetic signal of profile observations from a drifting surface

2020 ◽  
Author(s):  
Polina S. Osipova ◽  
◽  
Arkadiy V. Zlobinskiy ◽  
Vladimir V. Potapov ◽  
◽  
...  
Keyword(s):  
Electric Dipole ◽  
Born Approximation ◽  
Three Dimensional ◽  
Arctic Region ◽  
The Arctic ◽  
Electromagnetic Signal ◽  
Simulation Results ◽  
Dimensional Simulation ◽  
The Arctic Region

As part of the RSF project, the use of a drifting surface on which geophysical installations will be placed is proposed to study the environment in the Arctic region. The proposed method of electrical exploration is sounding with a circular electric dipole as a source. Studying the applicability of the technique requires three–dimensional simulation of the received signal. The paper shows some simulation results using the previously proposed algorithm based on the Born approximation.

scholarly journals Electromagnetic research in the Altai-Sayan mountain region

2021 ◽  
Vol 3 (2) ◽  
pp. 7-19
Author(s):  
Sergei Babushkin ◽  
Nina Nevedrova ◽  
Viktor Seleznev ◽  
Aleksei Liseikin
Keyword(s):  
Deep Structure ◽  
Three Dimensional ◽  
Sampling Step ◽  
Electromagnetic Sounding ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling ◽  
Electromagnetic Soundings ◽  
Time Domain Electromagnetic ◽  
The Time Domain ◽  
Sayan Mountain

A new software-measuring complex has been developed for recording non-stationary electromagnetic soundings based on mobile modules created on the basis of 24-bit ADCs, with built-in GPS receivers, with recorders located directly at the field sensors, arithmetic sampling step and recording of all signal realizations. The deep structure of the Uimon depression in Gorny Altai has been studied based on the time-domain electromagnetic sounding. Research is relevant due to the high seismic hazard of the area, and is also in demand for prospecting and exploration of predicted minerals here. To construct geoelectric models, data from several years of measurements were used, during which more than 60 soundings were performed. At this stage, the interpretation was performed using computer systems within the framework of a horizontally layered model. The interpretation results are presented in the form of sections and threedimensional visualizations, which clearly reflect the structure of the depression. Further, three-dimensional modeling and additional measurements are planned to verify and refine the results obtained.

scholarly journals Deriving Arctic 2 m air temperatures over snow and ice from satellite surface temperature measurements

2021 ◽  
Author(s):  
Pia Nielsen-Englyst ◽  
Jacob L. Høyer ◽  
Kristine S. Madsen ◽  
Rasmus T. Tonboe ◽  
Gorm Dybkjær ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Arctic Region ◽  
Satellite Observations ◽  
The Arctic ◽  
Clear Sky ◽  
Ice Surface ◽  
Air Temperatures ◽  
In Situ Observations ◽  
The Arctic Region

Abstract. The Arctic region is responding heavily to climate change, and yet, the air temperature of ice covered areas in the Arctic is heavily under-sampled when it comes to in situ measurements, resulting in large uncertainties in existing weather- and reanalysis products. This paper presents a method for estimating daily mean clear sky 2 meter air temperatures (T2m) in the Arctic from satellite observations of skin temperature, using the Arctic and Antarctic ice Surface Temperatures from thermal Infrared (AASTI) satellite dataset, providing spatially detailed observations of the Arctic. The method is based on a linear regression model, which has been tuned against in situ observations to estimate daily mean T2m based on clear sky satellite ice surface skin temperatures. The daily satellite derived T2m product includes estimated uncertainties and covers clear sky snow and ice surfaces in the Arctic region during the period 2000–2009, provided on a 0.25 degree regular latitude-longitude grid. Comparisons with independent in situ measured T2m show average biases of 0.30 °C and 0.35 °C and average root mean square errors of 3.47 °C and 3.20 °C for land ice and sea ice, respectively. The associated uncertainties are verified to be very realistic for both land ice and sea ice, using in situ observations. The reconstruction provides a much better spatial coverage than the sparse in situ observations of T2m in the Arctic, is independent of numerical weather prediction model input and it therefore provides an important supplement to simulated air temperatures to be used for assimilation or global surface temperature reconstructions. A comparison between in situ T2m versus T2m derived from satellite and ERA-Interim/ERA5 estimates shows that the T2m derived from satellite observations validate similar or better than ERA-Interim/ERA5 in the Arctic.

scholarly journals The role of tropopause polar vortices in the intensification of Summer Arctic cyclones

2021 ◽  
Author(s):  
Suzanne L. Gray ◽  
Kevin Hodges ◽  
Jonathan Vautrey ◽  
John Methven
Keyword(s):  
Three Dimensional ◽  
Arctic Region ◽  
The Arctic ◽  
Polar Regions ◽  
Synoptic Scale ◽  
Coherent Vortices ◽  
Cyclone Genesis ◽  
Ecmwf Reanalysis ◽  
The Arctic Region

<p>Human activity in the Arctic is expected to increase as new regions become accessible, with a consequent need for reliable forecasts of hazardous weather. Arctic cyclones are synoptic-scale cyclones developing within or moving into the Arctic region. Meso- to synoptic-scale tropopause-based coherent vortices called tropopause polar vortices (TPVs) are frequently observed in polar regions and are a proposed mechanism for Arctic cyclone genesis and intensification. While the importance of pre-existing tropopause-level features for cyclone development, and their existence as part of the three-dimensional mature cyclone structure, is well established in the mid-latitudes, evidence of the importance of pre-existing TPVs for Arctic cyclone development is more limited. Here we present a climatology and characteristics of summer Arctic cyclones and TPVs, produced by tracking them in the latest global ECMWF reanalysis (ERA5), and determine the role of pre-existing TPVs in the initiation and intensification of these cyclones.</p>

scholarly journals Deriving Arctic 2 m air temperatures over snow and ice from satellite surface temperature measurements

2019 ◽  
Author(s):  
Pia Nielsen-Englyst ◽  
Jacob L. Høyer ◽  
Kristine S. Madsen ◽  
Rasmus T. Tonboe ◽  
Gorm Dybkjær
Keyword(s):  
Surface Temperature ◽  
Arctic Region ◽  
Satellite Observations ◽  
The Arctic ◽  
Ice Surface ◽  
Air Temperatures ◽  
In Situ Observations ◽  
The Arctic Region ◽  
Snow And Ice

Abstract. The Arctic region is responding heavily to climate change, and yet, the air temperature of Arctic, ice covered areas is heavily under-sampled when it comes to in situ measurements, and large uncertainties exist in weather- and reanalysis products. This paper presents a method for estimating daily mean 2 meter air temperatures (T2m) in the Arctic from satellite observations of skin temperature, using the Arctic and Antarctic ice Surface Temperatures from thermal Infrared (AASTI) satellite dataset, providing spatially detailed observations of the Arctic. The method is based on a linear regression model which has been developed using in situ observations and daily mean satellite ice surface skin temperatures combined with a seasonal variation to estimate daily T2m. The satellite derived T2m product including estimated uncertainties covers clear sky snow and ice surfaces in the Arctic region during the period 2000–2009. Comparison with independent in situ measured T2m gives average correlations of 95.5 % and 96.5 % and average root mean square errors of 3.47 °C and 3.19 °C for land ice and sea ice, respectively. The reconstruction provides a much better spatial coverage than the sparse in situ observations of T2m in the Arctic, is independent of numerical weather prediction model input and it therefore provides an important alternative to simulated air temperatures to be used for assimilation or global surface temperature reconstructions. A comparison between in situ T2m versus T2m from satellite and ERA-Interim shows that the T2m derived from satellite observations validate similar or better than ERA-Interim estimates in the Arctic.

DEEP STRUCTURE OF THE FAULT ZONE IN THE MUKHOR-TARKATA SITE OF THE CHUYA DEPRESSION ACCORDING TO NON-STATIONARY ELECTROMAGNETIC SOUNDING DATA USING THREE-DIMENSIONAL MODELING

2021 ◽  
pp. 67-73
Author(s):  
A. M. Sanchaa ◽  
◽  
N. N. Nevedrova ◽  
N. V. Shtabel ◽  
◽  
...  
Keyword(s):  
Fault Zone ◽  
Time Domain ◽  
Deep Structure ◽  
Near Field ◽  
Three Dimensional ◽  
Structural Features ◽  
Electromagnetic Sounding ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling ◽  
Time Domain Electromagnetic

The paper presents the results of three-dimensional modeling of the fault structure in the central part of the Chuya depression in Gornyi Altai within the Mukhor-Tarkhata plot. On this site, from 2004 to the present, researchers of the IPGG SB RAS have been conducting regular annual observations by the method of nearfield time-domain electromagnetic sounding (TSB) to observe the process of restoration of the geological environment after the catastrophic Chuya earthquake with a magnitude of 7.3 in 2003. One of the aftereffects of the destructive earthquake is fracture zones expressed on the surface. Numerous deformations of the surface and industrial objects are observed in the area of the Mukhor-Tarkhata village. The fault zone with sub-vertical fracturing, identified at the site by geological and electromagnetic data, was activated after the earthquake. Detailed data on the geoelectric structure are required for the interpretation and analysis of monitoring data. Based on the interpretation of the near-field time-domain electromagnetic sounding data, the deep structure of the fault zone was obtained. To verify and clarify structural features of the geoelectric model, three-dimensional modeling was performed.

scholarly journals Short-lived climate forcers from current shipping and petroleum activities in the Arctic

2012 ◽  
Vol 12 (4) ◽  
pp. 1979-1993 ◽  
Author(s):  
K. Ødemark ◽  
S. B. Dalsøren ◽  
B. H. Samset ◽  
T. K. Berntsen ◽  
J. S. Fuglestvedt ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
State Of The Art ◽  
Three Dimensional ◽  
Arctic Region ◽  
The Arctic ◽  
Mean Values ◽  
Albedo Effect ◽  
Carbon Aerosols ◽  
Petroleum Extraction ◽  
The Arctic Region

Abstract. Emissions of short-lived climate forcers (SLCF) in the Arctic region are expected to increase, notably from shipping and petroleum extraction. We here discuss changes in atmospheric SLCF concentrations and resulting radiative forcing (RF) from present day shipping and petroleum activities in the Arctic. The three-dimensional chemistry transport OsloCTM2 and a state of the art radiative forcing model are used, based on a coherent dataset of present day Arctic emissions. We find that the net RF of SLCF of shipping in the Arctic region is negative, mainly due to the direct and indirect RF effects of sulphate emissions, while the net RF of SLCF of petroleum extraction is positive, mainly due to the effects of black carbon aerosols in the air and deposited on snow. Strong seasonal variations of the sensitivities to emissions are found. In terms of annual mean values we find that the Arctic sensitivities to SLCF is similar to global average sensitivities. One exception to this is the stronger snow/ice albedo effect from BC emissions.

704 Three dimensional Na lidar observation in the Arctic region

2013 ◽  
Vol 2013 (0) ◽  
pp. 190-191
Author(s):  
Wataru Muranaka ◽  
Takuya Kawahara ◽  
Hikaru Fukasawa ◽  
Satonori Nozawa
Keyword(s):  
Three Dimensional ◽  
Arctic Region ◽  
The Arctic ◽  
Lidar Observation ◽  
The Arctic Region
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