Investigation of Convection in the Upper Mantle Connected Thermomechanically with the Subduction Zone and Its Geodynamic Application to the Arctic Region and North East Asia

2021 ◽  
Vol 56 (3) ◽  
pp. 433-444
Author(s):  
L. I. Lobkovskii ◽  
M. M. Ramazanov
2021 ◽  
Vol 12 (3) ◽  
pp. 455-470
Author(s):  
L. I. Lobkovsky ◽  
M. M. Ramazanov ◽  
V. D. Kotelkin

A geodynamic model of upper mantle convection related to the Pacific subduction zone is mathematically substantiated and applied to investigate the Cretaceous-Cenozoic evolution of Central East Asia (CEA) and the Arctic. We present a solution for the two-dimensional stationary problem of thermal convection in the upper mantle layer, considering different Rayleigh numbers and taking into account the influence of the subduction process and lithospheric movements along the upper mantle base. We describe the results of 3D modeling of nonstationary upper mantle convection in a subduction zone. Our data give grounds to propose explanations for the entire spectrum of tectonic-magmatic processes developing within CEA in the Cenozoic and the Arctic in the Upper Cretaceous and Cenozoic. We discuss the reasons why the lithosphere in CEA and the Arctic is generally shifting towards the Pacific subduction zone, considering the presence of separate magmatic provinces and rift zones. In our opinion, this is due to the existence of a large horizontally elongated convective cell, which interior is composed of smaller isometric cells. This long cell creates the effect of conveyor dragging of the lithosphere, while its internal cells produce the effect of upper mantle plumes.


2018 ◽  
Vol 35 (4) ◽  
pp. 110-113
Author(s):  
V. A. Tupchienko ◽  
H. G. Imanova

The article deals with the problem of the development of the domestic nuclear icebreaker fleet in the context of the implementation of nuclear logistics in the Arctic. The paper analyzes the key achievements of the Russian nuclear industry, highlights the key areas of development of the nuclear sector in the Far North, and identifies aspects of the development of mechanisms to ensure access to energy on the basis of floating nuclear power units. It is found that Russia is currently a leader in the implementation of the nuclear aspect of foreign policy and in providing energy to the Arctic region.


2020 ◽  
Vol 33 (5) ◽  
pp. 480-489
Author(s):  
L. P. Golobokova ◽  
T. V. Khodzher ◽  
O. N. Izosimova ◽  
P. N. Zenkova ◽  
A. O. Pochyufarov ◽  
...  

2011 ◽  
Author(s):  
Chimerebere Onyekwere Nkwocha ◽  
Evgeny Glebov ◽  
Alexey Zhludov ◽  
Sergey Galantsev ◽  
David Kay

2021 ◽  
Vol 13 (10) ◽  
pp. 1884
Author(s):  
Jingjing Hu ◽  
Yansong Bao ◽  
Jian Liu ◽  
Hui Liu ◽  
George P. Petropoulos ◽  
...  

The acquisition of real-time temperature and relative humidity (RH) profiles in the Arctic is of great significance for the study of the Arctic’s climate and Arctic scientific research. However, the operational algorithm of Fengyun-3D only takes into account areas within 60°N, the innovation of this work is that a new technique based on Neural Network (NN) algorithm was proposed, which can retrieve these parameters in real time from the Fengyun-3D Hyperspectral Infrared Radiation Atmospheric Sounding (HIRAS) observations in the Arctic region. Considering the difficulty of obtaining a large amount of actual observation (such as radiosonde) in the Arctic region, collocated ERA5 data from European Centre for Medium-Range Weather Forecasts (ECMWF) and HIRAS observations were used to train the neural networks (NNs). Brightness temperature and training targets were classified using two variables: season (warm season and cold season) and surface type (ocean and land). NNs-based retrievals were compared with ERA5 data and radiosonde observations (RAOBs) independent of the NN training sets. Results showed that (1) the NNs retrievals accuracy is generally higher on warm season and ocean; (2) the root-mean-square error (RMSE) of retrieved profiles is generally slightly higher in the RAOB comparisons than in the ERA5 comparisons, but the variation trend of errors with height is consistent; (3) the retrieved profiles by the NN method are closer to ERA5, comparing with the AIRS products. All the results demonstrated the potential value in time and space of NN algorithm in retrieving temperature and relative humidity profiles of the Arctic region from HIRAS observations under clear-sky conditions. As such, the proposed NN algorithm provides a valuable pathway for retrieving reliably temperature and RH profiles from HIRAS observations in the Arctic region, providing information of practical value in a wide spectrum of practical applications and research investigations alike.All in all, our work has important implications in broadening Fengyun-3D’s operational implementation range from within 60°N to the Arctic region.


Sign in / Sign up

Export Citation Format

Share Document