基于回归模型的热带气旋条件下的海表降温参数化方案设计     

韦骏  刘欣  蒋国庆 《海洋学报(英文版)》2018,37(1):1-10

Combining a linear regression and a temperature budget formula, a multivariate regression model is proposed to parameterize and estimate sea surface temperature(SST) cooling induced by tropical cyclones(TCs). Three major dynamic and thermodynamic processes governing the TC-induced SST cooling(SSTC), vertical mixing, upwelling and heat flux, are parameterized empirically using a combination of multiple atmospheric and oceanic variables:sea surface height(SSH), wind speed, wind curl, TC translation speed and surface net heat flux. The regression model fits reasonably well with 10-year statistical observations/reanalysis data obtained from 100 selected TCs in the northwestern Pacific during 2001–2010, with an averaged fitting error of 0.07 and a mean absolute error of 0.72°C between diagnostic and observed SST cooling. The results reveal that the vertical mixing is overall the pre dominant process producing ocean SST cooling, accounting for 55% of the total cooling. The upwelling accounts for 18% of the total cooling and its maximum occurs near the TC center, associated with TC-induced Ekman pumping. The surface heat flux accounts for 26% of the total cooling, and its contribution increases towards the tropics and the continental shelf. The ocean thermal structures, represented by the SSH in the regression model,plays an important role in modulating the SST cooling pattern. The concept of the regression model can be applicable in TC weather prediction models to improve SST parameterization schemes.  相似文献   

气压对巴伦台钻孔倾斜的影响特征及机制研究     

许璐  邢喜民 《大地测量与地球动力学》2018,38(8):873-876

以巴伦台钻孔倾斜及分量应变辅助观测气压数据为研究对象，运用相关及小波分析研究气压对巴伦台钻孔倾斜的影响特征。结果表明，气压对巴伦台钻孔倾斜影响表现为准线性关系，对NS向的影响大于EW向。气压对NS向影响的显著频段有2 048～8 192、32 768～65 536 min，对EW向影响的显著频段为2 048～8 192 min。探讨了气压对巴伦台钻孔倾斜的影响机制。  相似文献   

垦利碱蓬Suaeda kenliensis J.W.Xing sp.nov.——碱蓬属一新种     

邢军武 《海洋科学》2018,42(9):51-54

报道了中国碱蓬属植物一新种——垦利碱蓬Suaeda kenliensis J.W.Xing sp.nov.。该种与南方碱蓬Suaeda australis(R.Br.)Moq.相近,但系一年生,种子具圆盘状和卵形两种形状,直径约2～3mm,叶长可达5～7 cm,无不定根,与南方碱蓬相区别。垦利碱蓬生长于潮间带和海水周期性淹没处。耐高盐,区域内海水盐度为25,滩涂表层含盐量在退潮后经日晒蒸发可达60‰以上。常形成单一种群的红海滩植被景观。模式标本存:中国科学院海洋生物标本馆;编号:MBM286537。采集地:莱州湾垦利海域潮间带泥滩。采集人:邢军武、曲宁、钟芳。  相似文献   

海南省农村多维贫困及影响因素的空间分异     

张金萍  林丹  周向丽  余珍鑫  宋伟  程叶青 《地理科学进展》2020,39(6):1013-1023

贫困具有多维属性,根据不同社会群体和背景从多维视角定义贫困已成为贫困问题研究的共识。依据Alkire-Foster多维贫困框架,拓展精准扶贫的“两不愁,三保障”识别标准,建立了涵盖教育、健康、居住、生活和收入指标的海南省农户多维贫困评估指标体系,基于海南省70个乡镇、134个贫困村3924户入户调查数据,采用双重临界值法评估了农户及村域多维贫困状况,进而运用地理加权回归(Geographically Weighted Regression,GWR)模型,分析了村域多维贫困影响因素的空间分异。结果显示,调查农户多维贫困率达18.22%,多维贫困程度严重的村多维贫困发生率不一定高,“两不愁、三保障”及收入指标对多维贫困指数的贡献率低。中、西部连片贫困地区多维贫困主要表现为较差的资产状况、不清洁的炊事燃料、较高的家庭成员患病率和较低的家庭成员最高学历。GWR模型分析表明,作为多维贫困最重要的影响因素,户主性别、户主受教育水平、女性劳动力占比和抚养比4个变量估计系数的空间分异明显。总体上,女性户主和低学历户主为主的地区倾向于更易发生多维贫困,二者的影响分别表现为从东到西、从北到南有所增强。女性劳动力占比为负向影响,抚养比为正向影响,呈现出自北向南增强的趋势,体现了海南贫困地区劳动力弱、女性相对更勤劳等典型地域特征。  相似文献   

阿拉尔河悬浮物对铀的吸附影响研究          下载免费PDF全文

钟翼  许建新  韩积斌  徐凯 《盐湖研究》2020,28(1):112-122

为了解阿拉尔河悬浮物对铀的吸附特性,通过静态吸附实验,研究了吸附时间、pH值、温度和铀初始浓度等因素对模拟含铀水中U(VI)去除率的影响,并从热力学和动力学方面对吸附过程进行了分析。结果表明,在T=25℃,溶液初始pH=7,接触时间为16 h时,悬浮物对铀的平衡吸附率最佳,为95.48%。随着铀初始浓度的增加,吸附量增加,但吸附率随之下降,升高温度有利于铀的吸附。铀在悬浮物上的吸附过程符合Langmuir等温吸附方程,说明悬浮物对铀为单分子层吸附,且化学吸附占主导地位。吸附动力学过程可用准二级吸附动力学模型描述,表明吸附主要受动力学控制,由两个以上步骤共同控制。FTIR和EDS分析结果表明,吸附过程中铀主要与悬浮物表面活性基团螯合并以表面络合吸附为主。吸附前后的能谱对比分析表明,吸附过程中存在离子交换行为。因此,悬浮物对铀的吸附机理是以表面络合吸附和离子交换为主、物理吸附为辅的混合吸附过程。  相似文献   

全球粮食安全格局的时空演化     

蔡建明  马恩朴  林静  廖柳文  韩燕 《地理学报(英文版)》2020,30(2):179-196

Food security is the primary prerequisite for achieving other Millennium Development Goals(MDGs).Given that the MDG of“halving the proportion of hungers by 2015”was not realized as scheduled,it will be more pressing and challenging to reach the goal of zero hunger by 2030.So there is high urgency to find the pattern and mechanism of global food security from the perspective of spatio-temporal evolution.In this paper,based on the analysis of database by using a multi-index evaluation method and radar map area model,the global food security level for 172 countries from 2000 to 2014 were assessed;and then spatial autocorrelation analysis was conducted to depict the spatial patterns and changing characteristics of global food security;then,multi-nonlinear regression methods were employed to identify the factors affecting the food security patterns.The results show:1)The global food security pattern can be summarized as“high-high aggregation,low-low aggregation”.The most secure countries are mainly distributed in Western Europe,North America,Oceania and parts of East Asia.The least secure countries are mainly distributed in sub-Saharan Africa,South Asia and West Asia,and parts of Southeast Asia.2)Europe and sub-Saharan Africa are hot and cold spots of the global food security pattern respectively,while in non-aggregation areas,Haiti,North Korea,Tajikistan and Afghanistan have long-historical food insecurity problems.3)The pattern of global food security is generally stable,but the internal fluctuations in the extremely insecure groups were significant.The countries with the highest food insecurity are also the countries with the most fluctuated levels of food security.4)The annual average temperature,per capita GDP,proportion of people accessible to clean water,political stability and non-violence levels are the main factors influencing the global food security pattern.Research shows that the status of global food security has improved since the year 2000,yet there are still many challenges such as unstable global food security and acute regional food security issues.It will be difficult to understand these differences from a single factor,especially the annual average temperature and annual precipitation.The abnormal performance of the above factors indicates that appropriate natural conditions alone do not absolutely guarantee food security,while the levels of agricultural development,the purchasing power of residents,regional accessibility,as well as political and economic stability have more direct influence.  相似文献   

Theory and measurement model of administrative region potential from a perspective of administrative division adjustment: Taking Chongqing city as a case study     

Wang  Kaiyong  Wang  Fuyuan 《地理学报(英文版)》2020,30(8):1341-1362

Journal of Geographical Sciences - There is a lack of basic theory and method to examine the effect of administrative division (AD) adjustment on the regional development. Based on the theory and...  相似文献   

喜马拉雅山脉中段土地覆被的垂直分异特征     

张镱锂  吴雪  郑度 《地理学报》2020,75(5):931-948

喜马拉雅山脉中段的珠穆朗玛峰等地,海拔高差巨大、生境复杂多变、土地覆被类型多样且植被垂直带谱完整,是全球范围内研究土地覆被垂直变化的理想场所。本文基于30 m空间分辨率的土地覆被数据（2010年）和DEM数据,在ArcGIS和Matlab平台的支持下,提出并运用脊线法、样带法和扇区法3种山地南北坡划分方法,研究了喜马拉雅山土地覆被垂直分布与结构差异。结果表明：① 山地土地覆被分布具有明确的垂直地带性结构特征,喜马拉雅中部土地覆被垂直带谱为南六北四式,土地覆被垂直带谱中具有人类活动的特点。② 南北坡之间的土地覆被垂直带谱差异明显,南坡土地覆被类型完整多样,北坡相对简单;对同类型土地覆被而言,南坡较北坡分布高程低、幅度宽。③ 依据各类型分布面积比随海拔变化情况,土地覆被类型在南北坡上的垂直分布可分为4种模式：冰川雪被、稀疏植被和草地为单峰分布型,裸地为南单峰北双峰分布型。④ 3种划分方法中,南坡的土地覆被垂直带结构具有相似性,而北坡的土地覆被垂直带结构存在差异,扇区法较好地反映了土地覆被自然分布格局。  相似文献   

辽宁瓦房店金刚石矿床50号岩管地质特征及找矿预测     

刘礼广  吴大天 《中国地质调查》2020,7(5):33-41

以辽宁瓦房店金刚石矿床50号岩管为例,系统分析了该矿床的地质特征。通过对斑状富金云母金伯利岩、含围岩角砾斑状金伯利岩和金伯利凝灰角砾岩进行岩石地球化学分析发现: 碳酸盐化金伯利凝灰角砾岩超基性成分较少,滑石化、蛇纹石化及碳酸盐化混合金伯利凝灰角砾岩超基性成分较多; 铬、镍、钛在金伯利凝灰角砾岩中的含量较低,在含围岩角砾斑状金云母金伯利岩中的含量略高,在斑状富金云母金伯利岩和斑状金伯利岩中的含量最高。该矿床主要为含围岩角砾斑状金伯利岩和斑状富金云母金伯利岩,其次为金伯利凝灰角砾岩、含围岩角砾斑状金云母金伯利岩和含金伯利物质角砾岩。含铬镁铝榴石、铬铁矿和碳硅石是金刚石的伴生矿物。水平方向上,金伯利岩含矿品位西部较富,东部较贫; 垂直方向上,金伯利岩含矿品位变化较小。通过三维建模,推测50号岩管不是根部相,而是受EW向推覆构造作用影响发生的断层错位,在其东侧600 m深处存在50-1号金伯利岩体。  相似文献   

基于广义回归神经网络的全球表层海水1°×1°二氧化碳分压数据推演     

钟国荣  李学刚  曲宝晓  王彦俊  袁华茂  宋金明 《海洋学报》2020,42(10):70-79

表层海水二氧化碳分压是评估海洋碳源汇强度的关键参数，但其实测数据较少、时空分布极不均匀，导致二氧化碳交换通量的估算有很大的不确定性，海洋源汇特征就不能确切获取。为了解决这个难题，在收集的表层大洋二氧化碳地图(Surface Ocean CO₂ Atlas，SOCAT)实测数据集基础上，运用广义回归神经网络建立二氧化碳分压与经纬度、时间、温度、盐度和叶绿素浓度间的非线性关系，构建了1998?2018年间全球1°×1°经纬度的表层海水二氧化碳分压格点数据，其标准误差为16.93 μatm，平均相对误差为2.97%，优于现有研究中的前反馈神经网络、自组织映射神经网络和机器学习算法等方法。根据构建的数据所绘制的全球表层海水二氧化碳分压的分布与现有研究有较好的一致性。  相似文献