On the Variability of Charleston South Carolina Winds, Atmospheric Temperatures, Water Levels, Waves and Precipitation

Atmospheric winds, air temperatures, water levels, precipitation and oceanic waves in the Charleston South Carolina (SC) coastal zone are evaluated for their intrinsic, internal variability over temporal scales ranging from hours to multi-decades. The purpose of this study was to bring together a plethora of atmospheric and coastal ocean state variable data in a specific locale, to assess temporal variabilities and possible relationships between variables. The questions addressed relate to the concepts of weather and climate. Data comprise the basis of this study. The overall distributions of atmospheric and coastal oceanic state variable variability, including wind speed, direction and kinematic distributions and state variable amplitudes over a variety of time scales are assessed. Annual variability is shown to be highly variable from year to year, making arithmetic means mathematically tractable but physically meaningless. Employing empirical and statistical methodologies, data analyses indicate the same number of intrinsic, internal modes of temporal variability in atmospheric temperatures, coastal wind and coastal water level time series, ranging from hours to days to weeks to seasons, sub-seasons, annual, multi-year, decades, and centennial time scales. This finding demonstrates that the atmosphere and coastal ocean in a southeastern U.S. coastal city are characterized by a set of similar frequency and amplitude modulated phenomena. Kinematic hodograph descriptors of atmospheric winds reveal coherent rotating and rectilinear particle motions. A mathematical statistics-based wind to wave-to-wave algorithm is developed and applied to offshore marine buoy data to create an hour-by-hour forecast capability from 1 to 24 hours;with confidence levels put forward. This affects a different approach to the conventional deterministic model forecasting of waves.

A Discussion on the Abnormal Tidal Phase Relationship between Water Level and Water Temperature in Qixian Well

Tidal phase of water temperature in Qixian well,Shanxi Province is ahead of water level,which is different from the normal tidal relationship between water temperature and water level. Observation curves of this phenomenon are introduced in this paper,and co-seismic response data of water temperature and water level are used to check the thermometer time system,confirming that this phenomenon is true. Using the harmonic analysis method,variations of time difference between water temperature and water level for the M2 wave are worked out,which indicates that this phenomenon exists during the whole observation. According to the variations of phase lags for water temperature and water level,and the survey of observation conditions, it is considered that the abnormal phenomenon may be related to inadequate passage of water caused by a well blockage at the depth where the water temperature probe was set.

Co-seismic Water Level and Temperature Responses of Some Wells to Far-Field Strong Earthquakes and Their Mechanisms

The observation of water temperature in deep wells has been carried out for more than 20 years in China.However,study on the mechanism of water temperature response to earthquakes is inadequate.During the study of the co-seismic response characteristics of water level and temperature in 121 wells within the China subsurface fluid monitoring network at the time of the December 26,2004,M-S8.7 Indonesia earthquake,we found regular response characteristics,that is,when the water level in a deep well oscillates,the water temperature in the same well will mostly experience a cycle from dropping to restoration at the same time.The process will continue for dozens of minutes to several hours.In order to confirm the observed phenomenon,we collected the digital water level and temperature observation data for 39 far-field strong earthquakes from the Tangshan well in Hebei Province(with the data set beginning in 2001).The same response characteristics were observed.Based on the analysis of the influencing factors that may cause the water temperature drop,the authors suggest the gas escape mechanism for co-seismic water temperature drop and posit two main factors that influence the water temperature drop during the process of gas escape.Finally,the authors provide a rational explanation of some observed phenomena based on the mechanism.

Mechanism of Photothermal Energy on the Growth and Yield of Rice under Water Level Regulation

The flooding caused by heavy rainfall in rice irrigation area and the drought caused by the drop of groundwater level are the research focus in the field of irrigation and drainage.Based on the comparative experiment and farmland water level control technology,this paper studied the average soil temperature under different soil layers(TM),the daily temperature change(TDC),the photosynthetic accumulation of single leaf and canopy in rice,and response of photothermal energy to rice root characteristics and growth factors in the paddy field under drought conditions.The results showed that the peak soil temperature under drought treatment was basically synchronous with the conventional irrigation,and the it was delayed by 2–6 h under flooding treatment compared to the drought treatment.Under different water gradients,the temperature decreased according to T_(L)>T_(CK)>T_(H)(L,H and CK represented water flooding,drought and control treatments),and the TDC was opposite.In addition to milky stage,the daily photosynthetic(Pn)accumulation of single leaf and canopy in the flooding and drought treated paddy fields were lower than conventional irrigation,and had a negative impact on leaf area index(LAI)and yield(YR),but did not form fatal damage.The root characteristic factors,RL(root length),RW(root weight),R-CR(root-canopy ratio)were promoted with drought,and YR under light drought was slightly higher than that under heavy drought.There was a strong positive correlation between TM and R-CR in all rice growth stages,while TDC-5 was negatively correlated with effective panicle number,TDC and R-CR in 20 cm soil layer were positively correlated.The correlation between daily Pn accumulation and YR was low,and the correlation between Pn and YR factors was negative or weak positive or negative.The total Pn was positively correlated with yield factors,and the correlation coefficient was higher than that of daily Pn.

The Impact of Water Level Decline on Water Quality in the Epilimnion of Lake Kinneret (Israel): Perennial Perspectives

Long term record (1933-2014) of Water Level (WL), nutrient concentrations, plankton densities, and temperatures in the epilimnion of Lake Kinneret was analyzed. The aim is to identify if water quality is deteriorated when the WL is low. It was found that water temperature increased and the composition and biomass of plankton communities were modified. Nitrogen and TDP decreased but TP slightly increased in the epilimnion during low WL conditions. The quality of epilimnetic water was not deteriorated and followed by a slight oligotrophism trend.

Characteristics and Mechanisms of Co-seismic Groundwater Responses in Tayuan Well

Co-seismic responses of the groundwater level and temperature in the Tayuan well of 68 earthquakes （Ms ≥ 7.0） from January 2004 to September 2007 were analyzed. Results show that the Tayuan well has a strong ability to record large earthquakes worldwide, and the coseismic response shows a pattern of water level oscillation →temperature decrease→ oscillation stop → temperature resumption. Further analyses indicate that the amplitude of the water level and temperature change is not ouly concerned with the epicenter distance and magnitude, but is also related to the temporal state of aquifer while the seismic wave arrives. Mechanisms of water level oscillation, temperature decrease, water level oscillation stop and temperature resumption are discussed, with the results from previous research on the co-seismic response mechanisms analyzed. These include gas escape, heat diffusion and cold water seepage. Results show that a single mechanism could not explain the co-seismic response of the Tayuan well water level to multiple earthquakes; the results were garnered from a variety of jointly acting mechanisms.

Tele-seismic coseismic well temperature changes and their interpretation

Coseismic water level oscillation and correlated deep water temperature changes have been observed in a water well at Tangshan City by high sensitivity measurement. Amount of water temperature changes depend on amplitude of water level oscillation. Coseismic water temperatures always decrease as water level oscillates, drop of temperature ranges from 0.001℃ to 0.01℃ corresponding to amplitude of water level oscillation from several centimeters to about one meter. Temperatures usually recover one to several hours after the oscillation. We suggest that the temperature drop is produced by dispersive transfer of heat as the water oscillates, and follow-up thermal conduction makes temperature recovery. Our finite element calculations support quantitatively the idea. High accuracy measurements of water temperature at different depths in the future may test our interpretation.

Temperature Effects on Unsaturated Hydraulic Property of Bentonite-Sand Buffer Backfilling Mixtures

The influence of temperature on the engineered properties of bentonite-sand mixtures （B/S） is of major concern in the design of engineered barriers in underground repositories for high-level radioactive waste disposal. We experimentally studied the influence of temperature on soil unsaturated hydraulic properties related to water holding capacity and permeability of GMZ B/S in China. The vapor equilibrium method and water infiltration apparatus were used to measure the soil water characteristic curve （SWCC） and unsaturated hydraulic conductivity （k）. The results show that the SWCC under different temperatures from 20℃ to 60 ℃ tends to be the same. Temperature influence on unsaturated permeability is more relevant at low suctions, no clear effect is detected below a degree of saturation of 74%, and experimental data show that temperature dependence on unsaturated permeability is small.

Impact of Accumulated Temperature on Wetland Vegetation Area in Poyang Lake

Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang Lake.This research used the classification and regression tree(CART)to classify normalized vegetation area index derived from MODIS LAI(Moderate Resolution Imaging Spectroradiometer Leaf Area Index)images from 2008 to 2014,according to different climate indexes,such as mean daily air temperature(n),accumulated temperature(jw),daily maximum temperature(g),daily minimum temperature(d),accumulative precipitation(j),water level(s)and average water level for 20 days preceding(a).The results showed that:(1)The accumulated temperature and the 20-day average WL(water level)were found to have the greatest impact on variation in wetland vegetation area,and they both dominated the classification process twice;(2)Two classification thresholds of accumulated temperature were 790°C and 1784°C,approximately corresponding to the beginning of April and midMay;(3)790°C could also be used as a threshold to select remote sensing images to analysis the annual variability of vegetation,i.e.while accumulated temperature is lower than 790°C,remote sensing images of similar accumulated temperature rather than similar date should be selected from different years for comparison.We also found that,effects of different hydrological factors on area of floodplain grasslands showed stage characteristics:(1)From January to March,water level changes slowly with less rainfall,as a result,the 20-day average WL which can interpret the hydrologic characteristics smoothly showed significant importance in this stage;(2)While entering April,intense rainfall make accumulative precipitation to be the dominating factor of classification;(3)From late April to mid-May,in condition of accumulative precipitation higher than 405 mm,daily water level is of most importance,because to the flood recession process as well as rapid water level fluctuations.

基于Solinst Levelogger3001水质参数采集处理系统的研究

采用Solinst Levelogger3001水质传感器与PC机构建了水质采集处理系统,利用Visual C++6.0的MFC框架及MSComm控件编写了采集处理软件。根据通信协议完成了主机和水质传感器之间通信,并对读取到的数据处理后利用MSChart控件实时显示,从而达到水质参数实时显示和实时监控。通过与随机采集处理软件实验比对表明,采集处理结果正确,达到了实时采集监控的目标。

Change of Gas Hydrate Reservoir and Its Effect on the Environment in Xisha Trough since the Last Glacial Maximum

In this article, Milkov and Sassen＇s model is selected to calculate the thickness of the gas hydrate stable zone （GHSZ） and the amount of gas hydrate in the Xisha （西沙） Trough at present and at the last glacial maximum （LGM）, respectively, and the effects of the changes in the bottom water temperature and the sea level on these were also discussed. The average thickness of the GHSZ in Xisha Trough is estimated to be 287 m and 299 m based on the relationship between the GHSZ thickness and the water depth established in this study at present and at LGM, respectively. Then, by assuming that the distributed area of gas hydrates is 8 000 km^2 and that the gas hydrate saturation is 1.2% of the sediment volume, the amounts of gas hydrate are estimated to be -2.76×10^10 m^3 and -2.87×10^10 m^3, and the volumes of hydrate-bound gases are -4.52×10^12 m^3 and -4.71×10^12 m^3 at present and at LGM, respectively. The above results show that the thickness of GHSZ decreases with the bottom water temperature increase and increases with the sea level increase, wherein the effect of the former is larger than that of the latter, that the average thickness of GHSZ in Xisha Trough had been reduced by -12 m, and that 1.9×10^11 m^3 of methane is released from approximately 1.1×10^9m^3 of gas hydrate since LGM. The released methane should have greatly affected the environment.

Research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 305 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model testing.This paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative analysis.The results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish reproduction.Innovative technical ideas and implementation scheme are adopted in this research.It can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

2016—2022年太湖胥口湾水质变化及对水温、水位的响应

明确太湖胥口湾水质特征及对环境变化的响应有利于维系区域水资源安全。研究追踪2016—2022年胥口湾水质变化趋势,分析了水质指标对水温和水位的响应。结果显示,胥口湾水质环境总体稳定,且总氮(TN)、氨氮(NH_(3)-N)、总磷(TP)浓度和COD_(Mn)均呈下降趋势。但胥口湾水温年均值呈现快速上升趋势,上升幅度大于0.086℃·a^(-1),对该区域生态稳定性形成威胁。冗余分析显示,虽然水温和水位对胥口湾水质环境波动的贡献率低于5%,但水温变化显著影响了水质环境(P<0.01),而水位波动不能有效解释水质变化过程。尽管如此,TN、NH_(3)-N浓度及COD_(Mn)、pH值对高水温(>30℃)较为敏感,而高水位(>3.8 m)显著影响了NH_(3)-N、TN、TP和叶绿素a浓度。总体而言,胥口湾水环境总体稳定趋好,但受水位尤其是水温影响较大。研究结果可为极端天气下水质管理提供借鉴。

不同应力水平下给定含水率混凝土低温有效预压性能试验研究

为评估低温储罐类预应力混凝土结构设计及安全性能,通过对混凝土施加各种初始预压应力水平(0.2、0.3、0.4、0.5、0.6及0.7)并在-160℃低温作用下的试验,系统地探讨其有效预压性能变化规律,同时比较较高和正常两种较为典型混凝土含水率情况对其影响差异。结果表明,随施加的初始预压应力水平提高,混凝土降温点和温均点时的有效预压应力损失率均呈下降的变化趋势,而其降温段和恒温段时的有效预压应力变化率的变化较为复杂;混凝土达其降温点后恒温阶段的有效预压应力损失均有所恢复,且随初始预压应力水平的提高其恢复程度更加明显;含水率对不同初始预压应力水平混凝土低温作用下降温点和恒温点时的有效预压应力损失率变化趋势未产生影响,仅使其变化程度有较明显的差异。

2021年玛多7.4级地震聊古1井同震响应特征分析

整理了聊古1井流量、水位、水温和水化学离子含量等流体测项在2021年青海玛多7.4级地震中的同震响应变化特征。结合聊古1井的构造背景,分析了同震变化的影响因素,初步探讨了同震变化机理。结果表明:聊古1井流量、水位及水温等流体测项在青海玛多7.4级地震发生后呈阶升型同震变化,井水离子含量也出现较大波动,明显高于背景值。本次青海玛多7.4级地震的流体同震响应特征表明聊古1井对远场地震反映灵敏,具有良好的映震效能。

温度对投入式水位计测量精度的影响研究

小沙湾水厂是黄河地表水给水工程的重要组成部分,是准能集团的重要水源地,而精准的水位数据对泵站取水工作有较大的影响。以浮子式水位计示值为参照,设计了投入式水位计示值的对比试验,对影响传感器精度的主要因素之一温度进行了研究,总结了温度与示值误差之间的关系。结果发现,在10~18℃时,水温对传感器精度影响很小;在18~25℃时,水温越高传感器精度越低;在26~30℃时,传感器精度随温度升高而升高。

2003—2022年昆仑山北坡典型湖泊水位变化及其归因

湖泊水位变化是湖泊系统动态变化的重要指标,对湖泊生态环境和水资源管理具有重要意义。基于ICESat-1、CryoSat-2、EnviSat以及ICESat-2多源测高卫星提取2003—2022年阿克赛钦湖、阿牙克库木湖、阿其克库勒湖、鲸鱼湖、长虹湖、萨利吉勒干南库勒湖的水位、湖泊集水区气温、降水及土地利用数据,利用趋势分析、Mann-Kendall和Pearson相关性等方法,定量分析湖泊水位变化特征,探讨湖泊水位变化的影响机制。结果表明:(1)多源测高卫星水位与水位数据集进行精度检验,变化趋势一致且相关性分析均通过显著性F检验。(2)近20 a,除萨利吉勒干南库勒湖外,其余湖泊水位呈显著上升趋势,长虹湖水位上升速率最大,以0.71 m·a^(-1)的速率变化,阿克赛钦湖水位上升速率最小,以0.29 m·a^(-1)的速率变化。(3)湖泊集水区气候要素差异较大,气温都呈上升速率的变化而降水量变化不一,而阿其克库勒湖、阿牙克库木湖、鲸鱼湖水位与降水呈正相关,除萨利吉勒干南库勒湖,典型湖水位与气温正相关。利用多源测高卫星数据,对湖泊水位变化进行分析,旨在揭示昆仑山北坡湖泊的水文变化规律,并为湖泊生态环境管理提供科学依据。

基于水位、水温、突水量和水质的充水水源识别神经网络模型

华北石炭-二叠系岩溶型煤田主采煤层底板的太原组薄层灰岩岩溶水和奥陶系或寒武系厚层灰岩岩溶水的水化学特征存在着天然相似性,单纯以若干项水化学指标辨识这些水源存在着误判甚至错判的风险。目的为解决寒武系灰岩水、太原组下段灰岩水和部分太原组上段灰岩水的水质指标相似而难以完全正确识别的问题,方法提出并构建基于水位、水温、突水量和水质识别充水水源的神经网络模型。以平顶山矿区充水水源识别为例,以阴阳离子毫克当量百分比[γ(Na)%,γ(Ca+Mg)%,γ(HCO_(3)^(-))%,γ(SO_(4)+Cl)%]、钠钙比、碱硬比、ρ(CO_(3)^(2−))、ρ(SO_(4)^(2−))、TDS、ρ(Na+K)、水位、水位动态变化、水温、突水量、衰减天数共15项指标作为识别因子,构建结构为15-10-6的神经网络模型。结果结果表明,所有训练样本对自身水源的拟合均值均超过0.98,比单纯以水质指标为识别因子的建模方法识别正确率高,能够有效消除因水质指标相似但水源不同而出现的误判或错判情况。结论建模方法已经嵌入平顶山矿区识别充水水源计算机软件和手机APP软件中,经过检验,识别正确率达到91.3%。

内蒙古通辽地震观测井水位和水温准同步变化机理分析

利用区域水文地质资料、水温梯度测试结果、区域地下水开采和降水等数据,分析了影响内蒙古通辽地震观测井水位和温度多年与年际变化的因素。在此基础上,构建了水动力地质模型,探讨了该井水位和水温准同步变化的机理。结果表明,区域地下水开采和降雨是影响该井水位和温度准同步变化的主要因素,冷水渗透理论可以很好地解释该井水位和水温的准同步变化。

地震水温观测仪器热迟滞性、漏热效应和仪器漂移实验研究

参照IEC 60751和ASTM E644-11国际标准,在0~100℃、0~70℃和0~50℃温度范围对石英晶体型、铂电阻型和热敏电阻型地震水温观测仪器(简称测温仪)开展热迟滞性研究,明确局浸法校准漏热效应,分析两者对测量不确定度的贡献,并查明仪器漂移特征。结果表明,测温仪热迟滞性随着测量点温度降低而减小,最大值为0.025 5℃(铂电阻型,50℃测量点);在相同测量点,石英晶体型测温仪的热迟滞性小于铂电阻型和热敏电阻型。采用局浸法校准时,感温元件的浸没深度应不小于30 cm,漏热效应最大值约为0.01℃(100℃测量点)。热迟滞分量对铂电阻型测温仪测量不确定度的贡献最大(约60.7%),石英晶体型测温仪则表现出最佳的测量准确度。不同类型传感器的仪器漂移测量结果接近,极差仅为0.000 3℃/24 h。未来可通过替换感温元件、优化设计、提升工艺和使用大深度恒温槽、保温装置、修正公式等方法提高仪器稳定性,减小校准漏热效应。