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Simulated perturbation in the sea-to-air flux of dimethylsulfi de and the impact on polar climate

第十三届中国卫星导航年会

作者： Quanrun Cheng Yize Zhang Junping Chen Shanghai Astronomical Observatory University of Chinese Academy of Sciences

In order to increase the understanding of the positioning performance of BDS in the polar regions, this paper analyzes PPP（precise point positioning） performance under five different combinations which include BDS-3（B1 IB3 I）,BDS（B1 CB2 a）,BDS（B1 IB3 I）,BDS（B1 CB2 a+B1 CB3 I） and GPS（L1 L2） using the observation data of 15 IGS（International GNSS Service） stations around the world for 30 days. The results show that the accuracy of the static PPP in polar regions in the three directions of NEU is 1.1 cm, 0.7 cm, and 1.7 cm, and the kinematic PPP accuracy is 10 cm, 9 cm, and 20 cm. The time for static PPP in the polar region to converge to within 10 cm in the three directions of NEU is less than 15 min, 11 min, and 19 min, while the time for kinematic PPP to converge within 20 cm is less than 17 min, 16 min, and 23 min.

关键词： polar region BeiDou Navigation Satellite System Precise Point Positioning convergence time

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Journal of Oceanology and Limnology 2021年第1期39卷 110-121页

作者： Bo QU Albert JGABRIC Rebecca JACKSON School of Science Nantong UniversityNantong 226219China School of Environment and Science Griffi th UniversityBrisbane 4111QLDAustralia

Marine biogenic emission of dimethylsulfi de(DMS)has been well recognized as the main natural source of reduced sulfur to the remote marine atmosphere and has the potential to aff ect climate,especially in the polar *** used a global climate model(GCM)to investigate the impact on atmospheric chemistry from a change to the contemporary DMS fl ux to that which has been projected for the late 21 st *** perturbed simulation corresponded to conditions that pertained to a tripling of equivalent CO 2,which was estimated to occur by year 2090 based on current worst-case greenhouse gas emission *** changes in zonal mean DMS fl ux were applied to 50°S–70°S Antarctic(ANT)and 65°N–80°N Arctic(ARC)*** results indicate that there are clearly diff erent impacts after perturbation in the southern and northern polar *** quantities related to the sulfur cycle show a higher increase in ***,most sulfur compounds have higher peaks in *** perturbation in DMS fl ux leads to an increase of atmospheric DMS of about 45%in ANT and 33.6%in *** sulfur dioxide(SO 2)vertical integral increases around 43%in ANT and 7.5%in ***(SO 4)vertical integral increases by 17%in ANT and increases around 6%in *** emissions increases by 21%in ANT and increases by 9.7%in ***,oxidation of DMS by OH increases by 38.2%in ARC and by 15.17%in *** optical depth(AOD)increases by 4%in the ARC and by 17.5%in the ANT,and increases by 22.8%in austral *** importance of the perturbation of the biogenic source to future aerosol burden in polar regions leads to a cooling in surface temperature of 1 K in the ANT and 0.8 K in the ***,polar regions in the Antarctic Ocean will have a higher off setting eff ect on warming after DMS fl ux perturbation.

关键词： dimethylsulfi de(DMS) sulfur dioxide DMS sea-to-air fl ux perturbation global climate model(GCM) polar region

Review of pre-processing technologies for ice cores

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Journal of Mountain Science 2018年第9期15卷 1950-1960页

作者： DU Wen-tao KANG Shi-chang QIN Xiang SUN Wei-jun ZHANG Yu-lan LIU Yu-shuo CHEN Ji-zu Qilian Shan Station of Glaciology and Ecologic Environment State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Population Resources and EnvironmentShandong Normal UniversityJinan 250014China

High-resolution ice core records covering long time spans enable reconstruction of the past climatic and environmental conditions allowing the investigation of the earth system's evolution. Preprocessing of ice cores has direct impacts on the data quality control for further analysis since the conventional ice core processing is time-consuming, produces qualitative data, leads to ice mass loss, and leads to risks of potential secondary pollution. However, over the past several decades, preprocessing of ice cores has received less attention than the improvement of ice drilling, the analytical methodology of various indices, and the researches on the climatic and environmental significance of ice core records. Therefore, this papers reviews the development of the processing for ice cores including framework, design as well as materials, analyzes the technical advantages and disadvantages of the different systems. In the past, continuous flowanalysis(CFA) has been successfully applied to process the polar ice cores. However, it is not suitable for ice cores outside polar region because of high level of particles, the memory effect between samples, and the filtration before injection. Ice core processing is a subtle and professional operation due to the fragility of the nonmetallic materials and the random distribution of particles and air bubbles in ice cores, which aggravates uncertainty in the measurements. The future developments of CFA are discussed in preprocessing, memory effect, challenge for brittle ice, coupling with real-time analysis and optimization of CFA in the field. Furthermore, non-polluting cutters with many different configurations could be designed to cut and scrape in multiple directions and to separate inner and outer portions of the core. This system also needs to be coupled with streamlined operation of packaging, coding, and stacking that can be implemented at high resolution and rate, avoiding manual intervention. At the same time, information

关键词： Ice core Alpine region polar region Pre-processing Innovation

OBSERVATIONAL STUDY OF MERIDIONAL VARIATION OF UV-B RADIATION DURING VOYAGES TO THE ARCTIC AND ANTARCTIC regionS

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Acta meteorologica Sinica 2002年第2期16卷 253-260页

作者：陆龙骅卞林根逯昌贵程彦杰 Chinese Academy of Meteorological Sciences Beijing 100081

Based on 1999-2000 observations made by the first Arctic and sixteenth Antactic scientific voyages,a study is undertaken about the meridional surface UV-B (B band ultraviolet rays) variations in 75°N-70°*** is mitigated as a function of latitudes and marked by lower radiation averaged over the Northern Hemisphere (NH) than over the Southern Hemisphere (SH),with its daily course basically similar to that of total *** polar summer noon hours (local time) and where ice albedo is maximum,the strongest UV-B irradiance on the surface perpendicular to sun's beams as found at equatorial latitudes is measured *** the areas near Zhongshan Station the increase of surface UV-B radiation shows a close relation to the decrease of ozone in the higher atmosphere but it has a less intimate relation with its concentration at ground.

关键词： polar region UV-B radiation meridional variation daily variation ozone

An outstanding example of cooperation between Arctic and non-Arctic countries in cryosphere and climate research: Sino-Finnish cooperation for more than 30 years

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Advances in polar Science 2021年第4期32卷 261-263页

作者： Matti LEPPÄRANTA Timo VIHMA Bin CHENG LEI Ruibo University of Helsinki Helsinki Fi-00014Finland Finnish Meteorological Institute Helsinki Fi-00101Finland Key Laboratory of polar Science MNRPolar Research Institute of ChinaShanghai 200136China

The cryosphere is interconnected with other components of the climate system through global exchange of water,energy,and ***-term sustainable and pragmatic scientific and technological cooperation on the cryosphere and climatology in polar and sub-polar regions between China and Finland began in the *** fields of bilateral cooperation include joint training of young scientists,joint field observations,climatological and ecological researches of polar and sub-polar sea ice,glaciers and frozen lakes,*** year 2020 marked the 70th anniversary of the establishment of diplomatic relations between China and *** order to celebrate the great achievements by Chinese and Finnish scientists in the fieldsof cryosphere and climate research,the Advances in polar Science invited scientists from both sides to jointly organize a Special Issue entitled“Sino-Finnish cooperation on cryosphere and climatology in polar and sub-polar regions”.In this Special Issue,we have collected 10 papers,with most papers created jointly by scientists of both *** fruitful scientific achievement is strongly benefited from the sustainability of ***,research,prediction,mitigation,and adaptation to the climate change in the polar and sub-polar regions will definitively stay in the focus for many decades to come.A new era of Finnish-Chinese scientific collaboration on cryosphere has begun.

关键词： China Finland international cooperation cryosphere climate polar region sub-polar region

Support Vector Machines for Cloud Detection over Ice-Snow Areas

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Geo-Spatial Information Science 2007年第2期10卷 117-120页

作者： CHEN Gang E Dongchen Department of Geography University of Calgary Calgary T2N 1N4 Canada Chinese Antarctic Center of Surveying and Mapping Wuhan University 129 Luoyu Road Wuhan 430079 China

In polar regions, cloud and underlying ice-snow areas are difficult to distinguish in satellite images because of their high albedo in the visible band and low surface temperature of ice-snow areas in the infrared band. A cloud detection method over ice-snow covered areas in Antarctica is presented. On account of different texture features of cloud and ice-snow areas, five texture features are extracted based on GLCM. Nonlinear SVM is then used to obtain the optimal classification hyperplane from training data. The experiment results indicate that this algorithm performs well in cloud detection in Antarctica, especially for thin cirrus detection. Furthermore, when images are resampled to a quarter or 1/16 of the full size, cloud percentages are still at the same level, while the processing time decreases exponentially.

关键词： cloud detection SVM texture analysis ice-snow covered area polar region

Progress in polar upper atmospheric physics research in China

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Advances in polar Science 2012年第2期23卷 55-71页

作者： LIU Ruiyuan YANG Huigen polar Research Institute of China Shanghai 200136China

The Chinese Antarctic Great Wall, Zhongshan, Kunlun and Arctic Yellow River stations have unique geographical locations, well suited to carry out polar upper atmospheric observations. This paper reviews the tremendous history of nearly 30 years of Chinese polar expeditions and major progress in polar upper atmospheric physics research. This includes the polar upper atmospheric physics conjugate observation system at Zhongshan Station in the Antarctic and Yellow River Station in the Arctic, and original research achievements in polar ionospheric fields, aurora and particle precipitation, the polar current system, polar plasma convection, geomagnetic pulsations and space plasma waves, inter-hemispheric comparisons of the space environment, space weather in polar regions, power spectrum of the incoherent scatter radar, ionospheric heating experiments and polar meso- spheric summer echoes, polar ionosphere-magnetosphere numerical simulation and others. Finally, prospects for Chinese polar upper atmospheric physics research are outlined.

关键词： upper atmospheric physics space physics geospace polar region ionosphere aurora

A　comparative　study　on　the　ionospheric　current　systems　in　the　Antarctic　and　Arctic　regions

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Chinese Journal of polar Science 1994年第1期5卷 1-10页

作者：徐文耀

The current systems representing the solar and lunar daily variations (S and L) of the gcomagnetic field have been calculated on the basis of the date obtained from the global network Of gcornagnetic observatories. The characteristics of these *** in the Antarctic and Arctic regions have been analysed comparatively. The results show that: (1) There are certain differences in the current systems of these two regions, that implies definite differences in the ionospheric dynamo process, responsible for both S and L, and the field-aligned current, responsible for S. The differences of the magnetic field structure in these two polar regions may be the basic reason of the above-mentioned differences. (2) There are remarkable differences in the internal current systems of these two polar regions, that is attributed to both the inducing field (current) and the underground conductivity. In general, the conductivity of the Antarctic region is higher than that of the Arctic region.

关键词： polar region geomagnetic field current system conductivity.

A preliminary study on using fresh animal excrements to monitor heavy metal contamination in the remote areas

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Acta Geochimica 2006年第S1期 78-79页

作者： Honghao LUO, Lijun XIA, Xuebin YIN, Liguang SUN Institute of polar Environment, University of Science and Technology of China, Hefei 230026, China