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31.
This study investigates the Arctic Ocean warming episodes in the 20th century using both a high-resolution coupled global climate model and historical observations. The model, with no flux adjustment, reproduces well the Atlantic Water core temperature (AWCT) in the Arctic Ocean and shows that four largest decadalscale warming episodes occurred in the 1930s, 70s, 80s, and 90s, in agreement with the hydrographic observational data. The difference is that there was no pre-warming prior to the 1930s episode, while there were two pre-warming episodes in the 1970s and 80s prior to the 1990s, leading the 1990s into the largest and prolonged warming in the 20th century. Over the last century, the simulated heat transport via Fram Strait and the Barents Sea was estimated to be, on average, 31.32 TW and 14.82 TW, respectively, while the Bering Strait also provides 15.94 TW heat into the west- ern Arctic Ocean. Heat transport into the Arctic Ocean by the Atlantic Water via Fram Strait and the Barents Sea correlates significantly with AWCT ( C = 0.75 ) at 0- lag. The modeled North Atlantic Oscillation (NAO) index has a significant correlation with the heat transport ( C = 0.37 ). The observed AWCT has a significant correlation with both the modeled AWCT ( C =0.49) and the heat transport ( C =0.41 ). However, the modeled NAO index does not significantly correlate with either the observed AWCT ( C = 0.03 ) or modeled AWCT ( C = 0.16 ) at a zero-lag, indicating that the Arctic climate system is far more complex than expected.  相似文献   
32.
China's overseas industrial parks contribute to political and economic cooperation,cultural exchange between home and host countries.Current studies mainly discuss the ef-fect of overseas industrial parks from the perspective of institutional and cultural difference,multi-scale coupling,as well as key partnerships,while little attention has been paid to the comprehensive analysis of overseas industrial parks.Based on a theoretical framework,this paper explores the overall effect of China's overseas industrial parks from the geo-effects perspective by using field interviews and a case study approach.The research shows that:(1)the geo-effects reveal the over effect of overseas industrial parks from the multiple and com-plementary dimensions of geopolitics,geo-economics,geo-society and geo-culture;(2)the Cambodia Sihanoukville Special Economic Zone,as a flagship BRI project,has produced the prominent and positive geo-effects;(3)the institutional-economic-cultural-environmental adaptability of overseas industrial parks is becoming important.Overseas industrial parks must be rooted in the politics,economy,society,and culture of host country;embedded in local social networks;balance the rights and interests of all stakeholders;and form the community of interests,community of destiny,and community of responsibility with political mutual trust,economic integration,cultural inclusiveness,and social harmony.The paper not only deepens the understanding about the overall effect of overseas industrial parks,but also provides decision support and theoretical reference for government policy makers and the overseas investment of enterprises.  相似文献   
33.
HESS J1303-631 is an extended TeV pulsar wind nebula powered by the pulsar PSR J1301-6305 detected with the High Energy Stereoscopic System. We present an analysis of the GeV γ-ray region of HESS J1303-631 with about14 yr of Fermi Large Area Telescope data. The GeV γ-ray emission, coincident with the very-high-energy source,has a photon index of 1.69 ± 0.09 in 10–500 GeV band, and the GeV morphology has an extension to the same direction as indicated in the TeV band. Moreover, the observed multi...  相似文献   
34.
An Ellerman Bomb(EB) is a kind of small scale reconnection event, which is ubiquitously formed in the upper photosphere or the lower chromosphere. The low temperature(<10,000 K) and high density(~1019–1022) plasma there makes the magnetic reconnection process strongly influenced by partially ionized effects and radiative cooling. This work studies the high β magnetic reconnection near the solar temperature minimum region based on high-resolution 2.5D magnetohydrodynamics simulations. The time...  相似文献   
35.
The Solar Upper Transition Region Imager(SUTRI) focuses on the solar transition region to achieve dynamic imaging observation of the upper transition region. In this paper, we report the optical system design, mechanical design, ultrasmooth mirror manufacture and measurement, EUV multilayer film coating, prelaunch installation and calibration for the SUTRI payload at IPOE, Tongji University. Finally, the SUTRI carried by the SATech-01satellite was successfully set to launch. All functions of thi...  相似文献   
36.
Pitted cones are cone-shaped structures, spanning from meters to kilometers in size, characterized by summit depressions. They are widely distributed on the surface of Mars with various origins, such as rootless cones, mud volcanoes,cinder or scoria cones, tuff rings or cones, pingos, and dirt cones. If the pitted cones identified in southern Utopia Planitia are mud volcanoes, as is speculated, they could be of particular interest due to the fact that mud volcanoes on Earth bring sediments from ...  相似文献   
37.
Volcanic activity is the main process for heat-material exchange and circulation for differentiated planets. All terrestrial planets in the Solar System, the Moon, the satellites of giant planets, and the dwarf planets once experienced or are currently experiencing volcanic activities. This paper summarized the volcanism(main volcanic features and their formation) on the Moon, Mars, Venus, and Mercury in the inner Solar System, volcanism and cryovolcanism on satellites(Io, Europa,Enceladus) of g...  相似文献   
38.
Machine learning is currently one of the research hotspots in the field of landslide prediction. To clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District, which is the most prone to landslide disasters in Guangzhou, was selected for landslide susceptibility evaluation. The evaluation factors were selected by using correlation analysis and variance expansion factor method. Applying four machine learning methods namely ...  相似文献   
39.
1Introduction In the ongoing discussion of climate change,the mass balance of Antarctica has received increasing attention during recent decades,since its reaction to global warming will strongly influence sea-level change(Schlosser and Oerter,2002).Many …  相似文献   
40.
The absorption reactions of arsenite on Fe (hydro-)oxides are studied. The three absorbent types are Fe(OH)3 gel and two Fe (hydro-)oxides, in which the Fe(OH)3 gel was dried in a microwave oven under vacuum at 80℃. It is found that pH changes from 9.71 to 10.36 in 6 minutes after the Fe (OH)3 gel was mixed with NaAsO2 solution, as the arsenite replaces the OH- in goethite and Fe(OH)3. At the 40th minute after the start of the reaction, pH decreases, which is most probably because that the monodentate surface complex of absorbed arsenite has changed into mononuclear-bidentate complex and released proton. The decline in pH values indicates not the end of the absorption but a change in the reaction type. Temperature and dissolved gas has little effect on these two types of reactions. The total absorption of arsenite increases after the absorbent is irradiated with ultrasound, which also lead to difficulty in separating the solids from solution. The absorption capacity for arsenite of Fe(OH)3 gel dried in a microwave oven under vacuum is 53.18% and 17.22% respectively better than that of Fe (OH)3 gel and gel dried at 80℃. The possible reasons are that the water molecules in the gel vibrates with high frequency under the effect of microwave irradiation, thereby producing higher porosity and improved surface activity.  相似文献   
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