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Using genetic algorithms to calibrate a dimethylsulfide production model in the arctic ocean

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Chinese Journal of oceanology and Limnology 2010年第3期28卷 573-582页

作者：瞿波 GABRIC J.Albert Nantong University Griffith University

The global climate is intimately connected to changes in the polar oceans. The variability of sea ice coverage affects deep-water formations and large-scale thermohaline circulation patterns. The polar radiative budget is sensitive to sea-ice loss and consequent surface albedo changes. Aerosols and polar cloud microphysics are crucial players in the radioactive energy balance of the arctic ocean. The main biogenic source of sulfate aerosols to the atmosphere above remote seas is dimethylsulfide (DMS). Recent research suggests the flux of DMS to the arctic atmosphere may change markedly under global warming. This paper describes climate data and DMS production (based on the five years from 1998 to 2002) in the region of the Barents Sea (30–35°E and 70–80°N). A DMS model is introduced together with an updated calibration method. A genetic algorithm is used to calibrate the chlorophyll-a (CHL) measurements (based on satellite SeaWiFS data) and DMS content (determined from cruise data collected in the arctic). Significant interannual variation of the CHL amount leads to significant interannual variability in the observed and modeled production of DMS in the study region. Strong DMS production in 1998 could have been caused by a large amount of ice algae being released in the southern region. Forcings from a general circulation model (CSIRO Mk3) were applied to the calibrated DMS model to predict the zonal mean sea-to-air flux of DMS for contemporary and enhanced greenhouse conditions at 70–80°N. It was found that significantly decreasing ice coverage, increasing sea surface temperature and decreasing mixed-layer depth could lead to annual DMS flux increases of more than 100% by the time of equivalent CO2 tripling (the year 2080). This significant perturbation in the aerosol climate could have a large impact on the regional arctic heat budget and consequences for global warming.

关键词： arctic ocean dimethyl sulfide mixed-layer depth chlorophyll-a dimethyl sulfoniopropionate

Variation of diffuse attenuation coefficient of downwelling irradiance in the arctic ocean

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Acta oceanologica Sinica 2014年第6期33卷 53-62页

作者： WANG Weibo ZHAO Jinping Key Laboratory of Physical oceanography Ministry of EducationOcean University of China

The diffuse attenuation coefficient （Kd） for downwelling irradiance is calculated from solar irradiance data measured in the arctic ocean during 3rd and 4th Chinese National arctic Research Expedition （CHINARE）, including 18 stations and nine stations selected for irradiance profiles in seawater respectively. In this study, the variation of attenuation coefficient in the arctic ocean was studied, and the following results were obtained. First, the relationship between attenuation coefficient and chlorophyll concentration in the arctic ocean has the form of a power function. The best fit is at 443 nm, and its determination coefficient is more than 0.7. With increasing wavelength, the determination coefficient decreases abruptly. At 550 nm, it even reaches a value lower than 0.2. However, the exponent fitted is only half of that adapted in low-latitude ocean because of the lower chlorophyll-specific absorption in the arctic ocean. The upshot was that, in the case of the same chlorophyll concentration, the attenuation caused by phytoplankton chlorophyll in the arctic ocean is lower than in low-latitude ocean. Second, the spectral model, which exhibits the relationship of attenuation coefficients between 490 nm and other wavelength, was built and provided a new method to estimate the attenuation coefficient at other wavelength, if the attenuation coefficient at 490 nm was known. Third, the impact factors on attenuation coefficient, including sea ice and sea water mass, were discussed. The influence of sea ice on attenuation coefficient is indirect and is determined through the control of enter- ing solar radiation. The linear relationship between averaging sea ice concentration （ASIC, from 158 Julian day to observation day） and the depth of maximum chlorophyll is fitted by a simple linear equation. In addition, the sea water mass, such as the ACW （Alaskan Coastal Water）, directly affects the amount of chlo- rophyll through taking more nutrient, and results in the higher

关键词： diffuse attenuation coefficient arctic ocean average sea ice concentration Alaskan Coastal Water

Signal quality analysis and quality check of BDS3 Precise Point Positioning in the arctic ocean

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Acta oceanologica Sinica 2022年第2期41卷 166-179页

作者： Xiaoguo Guan Hongzhou Chai Guorui Xiao Zhenqiang Du Wenlong Qi Xueping Wang College of Urban and Environmental Sciences Xuchang UniversityXuchang 461000China Institute of Geospatial Information Information Engineering UniversityZhengzhou 450001China Department of Civil Engineering Henan Vocational College of Water Conservancy and EnvironmentZhengzhou 450001China

This study analyzes the signal quality and the accuracy of BeiDou 3 rd generation Satellite Navigation System(BDS3) Precise Point Positioning(PPP) in the arctic ocean. Assessment of signal quality of BDS3 includes signal to noise ratio(SNR), multipath(MP), dilution of precision(DOP), and code-minus-carrier combination(CC). The results show that, 5 to 13 satellites are visible at any time in the arctic ocean area as of September 2018, which are sufficient for positioning. In the mid-latitude oceanic region and in the arctic ocean, the SNR is 25–52 dB Hz and the MP ranges from-2 m to 2 m. As the latitude increases, the DOP values show large variation, which may be related to the distribution of BDS satellites. The CC values of signals B1 I and BIC range from-5 m to 5 m in the mid-latitude sea area and the arctic ocean, which means the effect of pseudorange noise is small. Moreover, as to obtain the external precise reference value for GNSS positioning in the arctic ocean region is difficult, it is hard to evaluate the accuracy of positioning results. An improved isotropy-based protection level method based on Receiver Autonomous Integrity Monitoring is proposed in the paper, which adopts median filter to smooth the gross errors to assess the precision and reliability of PPP in the arctic ocean. At first, the improved algorithm is verified with the data from the International GNSS Service Station Tixi. Then the accuracy of BDS3 PPP in the arctic ocean is calculated based on the improved algorithm. Which shows that the kinematic accuracy of PPP can reach the decimeter level in both the horizontal and vertical directions, and it meets the precision requirements of maritime navigation.

关键词： BDS3 arctic ocean signal quality analysis protection level quality check Precise Point Positioning satellite navigation

Atmospheric concentration characteristics and gas/particle partitioning of PCBs from the North Pacific to the arctic ocean

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Acta oceanologica Sinica 2014年第9期33卷 32-39页

作者： WANG Zhen NA Guangshui GAO Hui WANG Yanjie YAO Ziwei National Marine Environmental Monitoring Center

Polychlorinated biphenyls （PCBs） were measured in atmospheric samples collected from the North Pacific to the arctic ocean between July and September 2012 to study the atmospheric concentration characteris-tics of PCBs and their gas/particle partitioning. The mean concentration of 26 PCBs （vapor plus particulate phase）（∑PCBs） was 19.116 pg/m^3with a standard deviation of 13.833 pg/m^3. Three most abundant conge-ners were CB-28, -52 and -77, accounting for 43.0% to∑PCBs. The predominance of vapor PCBs （79.0% to∑PCBs） in the atmosphere was observed.∑PCBs were negative correlated with the latitudes and inverse of the absolute temperature （1/T）. The significant correlation for most congeners was also observed between the logarithm of gas/particle partition coefficient （logKp） and 1/T. Shallower slopes （from ∑0.15 to ∑0.46, average ∑0.27） were measured from the regression of the logarithm of sub-cooled liquid vapor pressures （logpoL） and logKP for all samples. The difference of the slopes and intercepts among samples was insignifi-cant （p〉0.1）, implying adsorption and/or absorption processes and the aerosol composition did not differ significantly among different samples. By comparing three models, the J-P adsorption model, the octanol/air partition coefficient （KOA） based model and the soot-air model, the gas/particle partitioning of PCBs in the arctic atmosphere was simulated more precisely by the soot-air model, and the adsorption onto el-emental carbon is more sensitive than the absorption into organic matters of aerosols, especially for low-chlorinated PCB congeners.

关键词： PCBs gas/particle partitioning arctic ocean soot-air model semi-volatile organic compounds

同方期刊数据库

Difference of planktonic ciliate communities of the tropical West Pacific, the Bering Sea and the arctic ocean

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Acta oceanologica Sinica 2020年第4期39卷 9-17页

作者： Chaofeng Wang Haibo Li Zhiqiang Xu Shan Zheng Qiang Hao Yi Dong Li Zhao Wuchang Zhang Yuan Zhao Gérald Grégori Tian Xiao CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Jiaozhou Bay Marine Ecosystem Research Station Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Satellite ocean Environment Dynamics Hangzhou 310012China Second Institute of oceanography Ministry of Natural ResourcesHangzhou 310012China Aix-Marseille University Toulon UniversityCNRSIRDMediterranean Institute of Oceanology UM110Marseille 13288France

Ciliates are important components in planktonic food webs,but our understanding of their community structures in different oceanic water masses is *** report pelagic ciliate community characteristics in three seas:the tropical West Pacific,the Bering Sea and the arctic *** ciliate abundance had"bimodal-peak","surface-peak"and"DCM(deep chlorophyll a maximum layer)-peak"vertical distribution patterns in the tropical West Pacific,the Bering Sea and the arctic ocean,*** abundance proportion of tintinnid to total ciliate in the Bering Sea(42.6%)was higher than both the tropical West Pacific(7.8%)and the arctic ocean(2.0%).The abundance proportion of small aloricate ciliates(10–20μm size-fraction)in the tropical West Pacific was highest in these three *** arctic ocean had higher abundance proportion of tintinnids in larger LOD(lorica oral diameter)*** of redundant species increased from the arctic ocean to the tropical West *** result provided useful data to further understand ecology roles of planktonic ciliates in different marine habitats.

关键词： planktonic ciliates vertical distribution community structure tropical West Pacific Bering Sea arctic ocean

Contribution of Surface Waves to Sea Surface Temperatures in the arctic ocean

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Journal of ocean University of China 2024年第5期23卷 1151-1162页

作者： WEI Meng SHAO Weizeng SHEN Wei HU Yuyi ZHANG Yu ZUO Juncheng College of oceanography and Ecological Science Shanghai Ocean UniversityShanghai 201306China China Waterborne Transport Research Institute Ministry of Transport of the People’s Republic of ChinaBeijing 100088China

The aim of our study was to examine the contribution of surface waves from WAVEWATCH-III(WW3)to the variation in sea surface temperature(SST)in the arctic *** simulated significant wave height(SWH)were validated against the products from Haiyang-2B(HY-2B)in 2021,obtaining a root mean squared error(RMSE)of 0.45 with a correlation of 0.96 and scatter index of *** wave-induced effects,i.e.,wave breaking and mixing induced by nonbearing waves resulting in changes in radiation stress and Stokes drift,were calculated from WW3,ERA-5 wind,SST,and salinity data from the National Centers for Environmental Prediction and were taken as forcing fields in the Stony Brook Parallel ocean *** results showed that an RMSE of 0.81℃ with wave-induced effects was less than the RMSE of 1.11℃ achieved without the wave term compared with the simulated SST with the measurements from *** the four wave effects and sea ice freezing,the SST in the arctic ocean decreased by up to 1℃ in *** analysis revealed that the SWH was linear in SST(values without subtraction of waves)in summer and autumn,but this behavior was not observed in spring or winter due to the presence of sea *** interannual variation also presented a negative relationship between the difference in SST and SWH.

关键词： sea surface wave sea surface temperature arctic ocean

Analysis of Wave Distributions Using the WAVEWATCH-III Model in the arctic ocean

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Journal of ocean University of China 2022年第1期21卷 15-27页

作者： SHAO Weizeng YU Wupeng JIANG Xingwei SHI Jian WEI Yongliang JI Qiyan Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316000China National Satellite ocean Application Service Beijing 100081China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458China College of Meteorology and oceanography National University of Defense TechnologyNanjing 211101China College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China

In this work,we examined long-term wave distributions using a third-generation numerical wave model called WAVE-WATCH-III(WW3)(version 6.07).We also evaluated the influence of sea ice on wave simulation by using eight parametric *** select a suitable ice-wave parameterization,we validated the simulations from the WW3 model in March,May,September,and December 2017 against the measurements from the Jason-2 altimeter at latitudes of up to 60°***,all parameterizations ex-hibited slight differences,i.e.,about 0.6 m root mean square error(RMSE)of significant wave height(SWH)in May and September and about 0.9 m RMSE for the freezing months of March and *** comparison of the results with the SWH from the European Centre for Medium-Range Weather Forecasts for December 2017 indicated that switch IC4_M1 performed most effec-tively(0.68 m RMSE)at high latitudes(60°-80°N).Given this finding,we analyzed the long-term wave distributions in 1999-2018 on the basis of switch IC4_*** the seasonal variability of the simulated SWH was of two types,i.e.,‘U’and‘sin’modes,our results proved that fetch expansion prompted the wave ***,the interannual variability of the specific regions in the‘U’mode was found to be correlated with the decade variability of wind in the arctic ocean.

关键词： long-term wave distribution sea ice WAVEWATCH-III arctic ocean

Changes in area fraction of sediment-laden sea ice in the arctic ocean during 2000 to 2021

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Acta oceanologica Sinica 2024年第9期43卷 81-92页

作者： Yuanyang Xie Tingting Liu Na Li Ruibo Lei Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance Wuhan UniversityWuhan 430079China MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China

Sediment-laden sea ice plays an important role in arctic sediment transport and biogeochemical cycles,as well as the shortwave radiation budget and melt onset of ice ***,at present,there is a lack of efficient observation approach from both space and in situ for the coverage of arctic sediment-laden sea ***,both spatial distribution and long-term changes in area fraction of such ice floes are still *** study proposes a new classification method to extract arctic sediment-laden sea ice on the basic of the difference in spectral characteristics between sediment-laden sea ice and clean sea ice in the visible band using the MOD09A1 data with the resolution of 500 m,and obtains its area fraction over the pan arctic ocean during 2000−*** with Landsat-8 true color verification images with a resolution of 30 m,the overall accuracy of our classification method is 92.3%,and the Kappa coefficient is *** impact of clouds on the results of recognition and spatiotemporal changes of sediment-laden sea ice is relatively small from June to July,compared to that in May or ***,sediment-laden sea ice mostly appears over the marginal seas of the arctic ocean,especially the continental shelf of Chukchi Sea and the Siberian *** with the retreat of arctic sea ice extent,the total area of sediment-laden sea ice in June-July also shows a significant decreasing trend of 8.99×10^(4) km^(2) per *** occurrence of sediment-laden sea ice over the arctic ocean in June-July leads to the reduce of surface albedo over the ice-covered ocean by 14.1%.This study will help thoroughly understanding of the role of sediment-laden sea ice in the evolution of arctic climate system and marine ecological environment,as well as the heat budget and mass balance of sea ice itself.

关键词： sea ice sediments optical remote sensing arctic ocean

Isolation and phylogenetic assignation of actinomycetes in the marine sediments from the arctic ocean

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Acta oceanologica Sinica 2005年第6期24卷 135-142页

作者： YU Yong LI Huirong ZENG Yinxin CHEN Bo State oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China

Actinomycetes in five marine sediments collected from the arctic ocean atdepths of 43 to 3 050 m were cultivated using a variety of media. A total of 61 actinomycetecolonies with substrate mycelia only were observed, and no colonies with aerial mycelia wereobserved under aerobic conditions at 15℃. From these colonies, 28 were selected to representdifferent morphological types. Denaturing gradient gel electrophoresis (DGGE) was used to check thepurity of isolates and select representatives for subsequent sequencing. Phylogentic analyses basedon nearly full-length 16S ribosomal RNA gene (rDNA) sequences indicated that the actinomycetesisolated were accommodated within genus Rhodococcus of family Nocardiaceae, genus Dietzia of familyDietziaceae, genera Janibacter and Terrabacter of family Instrasporangiaceae and genera Kocuria andA nhrobacter of family Micrococcaceae. One of the strains (P27-24) from the deep-sea sediment atdepth of 3 050 m was found to be identical in 16S rDNA sequence(1474/1474) with theradiation-resistant Kocuria rosea ATCC 187~T isolated from air. More than half of the isolatesshowed the similarities ranging from 99.5% to 99.9% in 16S rDNA sequence to dibenzofran-degrading,butyl 2-ethylhexanoate-hydrolysising and nitrile-metabolizing actinomycetes. All the strainsisolated were psychrotolerant bacteria and grew better on the media prepared with natural seawaterthan on the media prepared with deionized water. Three of them (Dietzia sp. P27-10, Rhodococcus sp.S11-3 and Rhodococcus sp.P11-5) had an obligate growth requirement for salt, confirming that thesestrains are indigenous marine actinomycetes.

关键词： marine actinomycetes genetic diversity arctic ocean