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On the Shallowing of Antarctic Low-Level Temperature Inversions Projected by CESM-LE under RCP8.5

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Journal of Meteorological Research 2024年第3期38卷 586-599页

作者： Minghu DING Lin ZHANG Tingfeng DOU Yi HUANG Yingyan LUO Junmei LYU cunde xiao State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Key Laboratory of Meteorology and Ecological Environment of Hebei Province Hebei Provincial Institute of Meteorological SciencesShijiazhuang050021China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China

Temperature inversions are frequently observed in the boundary layer and lower troposphere of polar *** variations of the low-level temperature inversions in these regions,especially the Antarctic,are still poorly *** to the scarcity of observations in the Antarctic,reanalysis data and numerical simulations are often used in the study of Antarctic climate *** on ERA-Interim,ERA5,JRA-55,and NCEP-NCAR reanalysis products,this study examines temporal and spatial variations of Antarctic inversion depth in austral autumn and winter during *** inversions are found to occur over the high plateau areas of the Antarctic *** on the Mann-Kendall test,ERA-Interim and ERA5 data reveal that the Antarctic inversion depth in austral autumn and winter increased during 1992-2007,roughly maintained afterwards,and then significantly decreased since around *** decrease trend is more obvious in the last two months of ***,JRA-55 better represents the spatial distribution of inversion depth,and ERA-Interim has better interannual *** Community Earth System Model Large Ensemble(CESM-LE)30-member simulations in 1979-2005 were first verified against JRA-55,showing reasonable consistency,and were then used to project the future changes of Antarctic low-level inversion depth over 2031-2050 under *** CESM-LE projection results reveal that the temperature inversion will shallow in the Antarctic at the end of the 21st century,and the decrease in depth in autumn will be more pronounced than that in *** particular,the temperature inversion will weaken over the ice-free ocean,while it will remain stable over the ice sheet,showing certain spatial heterogeneity and seasonal dependence on the underlying cryospheric surface *** addition,the decrease of inversion depth is found closely linked with the reduction in sea ice,suggesting the strong effect of global warming on the thermal structure change o

关键词： boundary layer temperature inversion Antarctic climate change Community Earth System Model Large Ensemble(CESM-LE)

Migration and role of zinc in biogeochemical cycles in the Antarctic Ice Sheet and the Southern Ocean

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Advances in Polar Science 2024年第2期35卷 157-177页

作者： LIU Jingwen LI Chuanjin DU Zhiheng SHI Guitao DING Minghu SUN Bo xiao cunde State Key Laboratory of the Cryosphere Science Northwest Institute of the Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Polar Science MNRPolar Research Institute of ChinaShanghai 200136China Key Laboratory of Geographic Information Science(Ministry of Education) School of Geographic Sciences and Institute of Eco-ChongmingEast China Normal UniversityShanghai 200241China Institute of Global Change and Polar Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Zinc(Zn),a widespread metal in the Earth’s crust,serves as a crucial nutrient in the Southern Ocean’s primary *** on Zn in Antarctic snow and ice offer insights into the origins of this metal and its transport routes,as well as its impact on the biogeochemical processes within the Antarctic atmosphere–land–ocean *** review examines research on the spatial and temporal distribution of Zn in Antarctic snow and ice,as well as in Southern Ocean *** includes an overview of advanced methods for sampling and analyzing Zn,along with explanations for the observed *** review also discusses various sources of Zn as a nutrient to the Southern ***,it addresses prospective issues related to the use of Zn isotopes in identifying atmospheric sources and their biogeochemical effects on the development of the Southern Ocean ecosystem.

关键词： zinc biogeochemical cycles Antarctic Ice Sheet Southern Ocean

基于机器学习和动力过程的南极冰架崩解特征分析

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地球科学进展 2024年第8期39卷 837-846页

作者：龙清云张通王彻车涛效存德北京师范大学地表过程与资源生态国家重点实验室北京100875 首都师范大学水资源安全北京实验室北京100048 中国科学院西北生态环境资源研究院甘肃兰州730000

冰架崩解对南极质量损失和动力过程有着直接影响,因此研究其变化的空间特征、环境条件和受控因子尤为重要。基于机器学习算法和冰盖动力模式,利用2005—2020年南极冰架崩解遥感数据、冰架表面裂隙数据、冰架支撑值、南极冰架损伤空间分... 详细信息

冰架崩解对南极质量损失和动力过程有着直接影响,因此研究其变化的空间特征、环境条件和受控因子尤为重要。基于机器学习算法和冰盖动力模式,利用2005—2020年南极冰架崩解遥感数据、冰架表面裂隙数据、冰架支撑值、南极冰架损伤空间分布数据以及表面融化数据,结合机器学习二元分类算法,分析了18种影响冰架动力过程的特征要素的重要性,并测算7种不同机器学习算法的准确性。结果表明,随机森林算法在冰架崩解事件的二元分类中具备最高准确率,其中,冰架表面流速和冰架表面融水对冰架崩解具有较高的影响,表明利用冰架自身动力性质和外部环境影响因子进行冰架崩解的预测具有一定的可行性。后续需进一步耦合动力模式和机器学习算法,并构建相应的数值模式体系,来刻画更高时空分辨率的冰架崩解事件强度和范围。

关键词：南极冰盖冰架崩解冰架损伤冰盖动力模式机器学习

A Preliminary Investigation of Arctic Sea Ice Negative Freeboard from in-situ Observations and Radar Altimetry

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Journal of Ocean University of China 2021年第2期20卷 307-314页

作者： LI Shutong DOU Tingfeng xiao cunde State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Land Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

The negative freeboard of sea ice(i.e., the height of ice surface below sea level) with subsequent flooding is widespread in the Southern Ocean, as opposed to the Arctic, due to the relatively thicker ice and thinner snow. In this study, we used the observations of snow and ice thickness from 103 ice mass balance buoys(IMBs) and NASA Operation IceBridge Aircraft Missions to investigate the spatial distribution of negative freeboard of Arctic sea ice. The Result showed that seven IMBs recorded negative freeboards, which were sporadically located in the seas around Northeast Greenland, the Central Arctic Ocean, and the marginal areas of the Chukchi–Beaufort Sea. The observed maximum values of negative freeboard could reach-0.12 m in the seas around Northeast Greenland. The observations from IceBridge campaigns also revealed negative freeboard comparable to those of IMBs in the seas around North Greenland and the Beaufort Sea. We further investigated the large-scale distribution of negative freeboard using NASA CryoSat-2 radar altimeter data, and the result indicates that except for the negative freeboard areas observed by IMBs and IceBridge, there are negative freeboards in other marginal seas of the Arctic Ocean. However, the comparison of the satellite data with the IMB data and IceBridge data shows that the Cryosat-2 data generally overestimate the extent and magnitude of the negative freeboard in the Arctic.

关键词： Arctic sea ice negative freeboard ice mass balance buoy IceBridge CryoSat-2

Sea Salt Sodium Record in a Shallow Ice Core from East Antarctica as a Potential Proxy of the Antarctic Sea Ice Extent in Southern Indian Ocean

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Journal of Ocean University of China 2019年第6期18卷 1351-1359页

作者： YANG Jiao DU Zhiheng xiao cunde State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Antarctic sea ice has experienced an increasing trend in recent decades,especially in the Ross Sea and Indian Ocean *** ice variability affects greatly the maritime airmass transport from high latitude to Antarctic *** we present a new ice core record of sea salt sodium(ssNa+)concentration at annual-resolution in the Princess Elizabeth Land spanning from 1990 to 2016,showing that this marker could be used as a potential proxy for reconstructing the sea ice extent(SIE)in the Southern Indian Ocean(SIO)given their significant correlation(R=-0.6,P1)over the past 27 *** correlation and composite analyses results show that the ssNa^+at the 202 km inland from Zhongshan Station and the SIE changes in SIO are closely related to the Indian Ocean Dipole(IOD)and Southern Annular Mode(SAM).The northward wind in central SIO occurs during positive IOD and the strengthened westerlies occurs during positive SAM,both of which favor increased sea ice in SIO and lead to the decreased ssNa^+concentration at the coastal site.

关键词： ice core East Antarctica sea ice climate change southern Indian Ocean

Variations in stable hydrogen and oxygen isotopes in atmospheric water vapor in the marine boundary layer across a wide latitude range

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Journal of Environmental Sciences 2014年第11期26卷 2266-2276页

作者： Jingfeng Liu cunde xiao Minghu Ding Jiawen Ren State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences University of Chinese Academy of Sciences Chinese Academy of Meteorological Sciences

The newly-developed cavity ring-down laser absorption spectroscopy analyzer with special calibration protocols has enabled the direct measurement of atmospheric vapor isotopes at high spatial and temporal resolution. This paper presents real-time hydrogen and oxygen stable isotope data for atmospheric water vapor above the sea surface, over a wide range of latitudes spanning from 38°N to 69°S. Our results showed relatively higher values of 8180 and 82H in the subtropical regions than those in the tropical and high latitude regions, and also a notable decreasing trend in the Antarctic coastal region. By combining the hydrogen and oxygen isotope data with meteoric water line and backward trajectory model analysis, we explored the kinetic fractionation caused by subsiding air masses and related saturated vapor pressure in the subtropics, and the evaporation-driven kinetic fractionation in the Antarctic region. Simultaneous observations of meteorological and marine variables were used to interpret the isotopic composition characteristics and influential factors, indicating that d-excess is negatively correlated with humidity across a wide range of latitudes and weather conditions worldwide. Coincident with previous studies, d-excess is also positively correlated with sea surface temperature and air temperature （Tair）, with greater sensitivity to Tair. Thus, atmospheric vapor isotopes measured with high accuracy and good spatial- temporal resolution could act as informative tracers for exploring the water cycle at different regional scales. Such monitoring efforts should be undertaken over a longer time period and in different regions of the world.

关键词： Atmospheric vapor isotope Isotope fractionation Water cycle CHINREN

Reconstruction of autumn sea ice extent changes since AD1289 in the Barents-Kara Sea, Arctic

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Science China Earth Sciences 2018年第9期61卷 1279-1291页

作者： Qi ZHANG cunde xiao Minghu DING Tingfeng DOU Institute of Polar Meteorology Chinese Academy of Meteorological Sciences State Key Laboratory of Earth Surface and Resources Ecology Beijing Normal University College of Resources and Environment University of Chinese Academy of Sciences

Using high-resolution ice core and tree ring proxies for sea ice extent （SIE）, we reconstructed a robust time series of autumn SIE over the Barents-Kara （B-K） sector of the Arctic from AD 1289-1993. After intercomparing the results and statistical parameters using the ordinary least squares regression （OLSR）, the principle component regression （PCR） and the partial least squares regression （PLSR） methods, SIE time series were synthesized into a more robust series using the weighted average method, which used the explained variances as weights. The results showed that from the end of the 13th century to the end of 18th century, the autumn B-K SIE was large, with large variations and a slightly expanding trend overall. This reflected significant multideeadal oscillations under the Little Ice Age （LIA） background. The B-K SIE began to decrease at the end of the 18th century, and a shrinking trend became significant during the second half of the 19th century, which lasted into the 1930s- 1940s. The 1930s-1940s was a period with a relatively low SIE in the B-K Sea, and the SIE had a short period of expansion from the 1940s-1970s. However, the B-K SIE has continuously and significantly shrank since the 1970s. The reduction in the B-K SIE since the end of the 18th century has been unprecedented in both duration and speed over the last 700 years. The B-K SIE has retreated significantly since the 1970s, with a speed 6.18 times greater than the former mean retreating speed. The industrial revolution may be a dominant factor in this result. The Arctic SIE in recent years may be the lowest it has been over the last millennium.

关键词： Arctic Sea ice Ice core Tree rings Paleoclimatology Global warming

Changes in the Proportion of Precipitation Occurring as Rain in Northern Canada during Spring–Summer from 1979–2015

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Advances in Atmospheric Sciences 2018年第9期35卷 1129-1136页

作者： Wei HAN cunde xiao Tingfeng DOU Minghu DING Nanjing University of Information Science and Technology Nanjing 210044China Institute of Polar Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Earth Surface and Resource Ecology Beijing Normal UniversityBeijing 100875China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Changes in the form of precipitation have a considerable impact on the Arctic cryosphere and ecological system by influencing the energy balance and surface runoff. In this study, station observations and ERA-Interim data were used to analyze changes in the rainfall to precipitation ratio（RPR） in northern Canada during the spring–summer season（March–July）from 1979–2015. Our results indicate that ERA-Interim describes the spring–summer variations and trends in temperature and the RPR well. Both the spring–summer mean temperature [0.4℃–1℃（10 yr）^（-1）] and the RPR [2%–6%（10 yr）^（-1）] increased significantly in the Canadian Arctic Archipelago from 1979–2015. Moreover, we suggest that, aside from the contribution of climate warming, the North Atlantic Oscillation is probably another key factor influencing temporal and spatial differences in the RPR over northern Canada.

关键词： climate change rainfall to precipitation ratio northern Canada North Atlantic Oscillation

A preliminary study on measurements of black carbon in the atmosphere of northwest Qilian Shan

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Journal of Environmental Sciences 2012年第1期24卷 152-159页

作者： Shuyu Zhao Jing Ming cunde xiao Weijun Sun Xiang Qin State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesGansu 730000China China National Climate Center Beijing 100081China Qilian Shan Station of Glaciology and Ecologic Environment Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesGansu 730000China

Black carbon （BC） concentration and meteorological data are measured discontinuously from May 2009 to March 2011,at the Qilian Shan Station of Glaciology and Ecologic Environment （hereafter ＂QSSGEE＂）,located near the terminal of the Laohugou No.12 Glacier in northwestern Qilian Shan,*** measured the daily,monthly and seasonal variations of BC concentration in the atmosphere and discussed the possible emission *** carbon background concentration in this region varied in the range of 18–72 ng/m 3 with the highest in summer and the lowest in *** relations between BC concentration and surface wind direction indicated that BC concentration was higher when northwest wind prevails while lower when southeast wind *** masses backward trajectories showed the potential emission sources in the *** positive correlations between daily mean BC concentration and relative humidity indicated that BC might be one of important cloud condensation *** hypothesis needs to be confirmed further through cloud microphysical features in this region.

关键词： black carbon Qilian Shan cloud condensation nuclei