Simulation of the Direct Radiative Effect of Mineral Dust and Sea Salt Aerosols in a Doubled Carbon Dioxide Climate

The authors examine the equilibrium climatic response to the direct radiative effect （DRE） of mineral dust and sea salt aerosols in a doubled-CO2 climate with two-way coupling of aerosol-climate interactions.In response to the drier and windier conditions,dust emissions increase by 26％ in the Sahara Desert and by 18％ on the global scale relative to present day.Sea salt emissions increase in high latitudes （＞60°） but decrease in middle latitudes （30°-60°） of both hemispheres due to the poleward shift of westerlies,leading to a 3％ decrease in global emissions.The burdens of dust and sea salt increase by 31％ and 7％ respectively,because reductions in rainfall over the tropical oceans increase the lifetime of particles in the warmer climate.The higher aerosol loading in the doubled-CO2 climate reinforces aerosol DRE by -0.2 W m-2,leading to an additional cooling of 0.1℃ at the surface compared with the climatic effects of aerosols in present day.The additional cooling from changes in natural aerosols compensates for up to 15％ of the regional warming induced by doubled CO2.

The concentration variation features of sea salt ions and non sea salt ions in a firn core recovered from Princess Elizabeth Land, East Antarctica

A 51.85 m firn core drilled in Princess Elizabeth Land, Antarctica, during the 1996-1997 Chinese First Antarctic Inland Expedition, has been measured for δ 18 O and major ions. Based on the high quality data of the seasonal variations of major ions, the firn core was dated with errors within ±3 years. The 51.85 m firn core record extends for 251 years (A. D. 1745-1996). The results of the glaciochemistry data of the firn core show that the mean concentrations of Cl -, Na + and Mg 2+ are similar to those reported from other coastal areas in East Antarctica. However, mean concentrations of Ca 2+ are much higher than those reported from other regions, this anomaly phenomenon may be related to the strong local terrestrial sources. It is found that the variations of three kinds of sea salt ions (Cl -, Na + and Mg 2+ ) in the past 150 years show very similarly rising trends, which may be the results the Southern Hemisphere warming in the past century.

High Contribution of Sea Salt Aerosols on Atmospheric Particles Measured at an Urban Tropical Location in Reunion Island

PM10 was monitored during 2008-2011 period at LUT and BON, two urban tropical stations close to each other at Saint-Pierre city, in Reunion Island (south-western Indian Ocean). During the study period, notable PM10 concentrations are observed at BON close to the coasts. At LUT, a more inland site, the daily PM10 concentration range between 13 and 70 μg/m3. Importantly, the limit value for the protection of the human health is systematically exceeded at BON while it is never exceeded at LUT. Also, the quality objective (QO: 30 μg/m3, on annual average) and the limit value for the human health protection (LV: 40 μg/m3, on annual average) are exceeded at BON each year during 2008-2011, while at LUT no regulatory values are exceeded. Nitrogen dioxide, an atmospheric tracer of anthropogenic activities was also monitored at LUT and BON. The mean diurnal NO2 variation is of the same level and order of magnitude and exhibits a similar pattern at both stations suggesting that distinct sources influence the PM10 at LUT and at BON. Chemical analysis was performed on daily filters sampled in September-November 2011 at the two stations to determine the sea salt contribution on PM10 across Saint-Pierre city. It showed that the sea salt contribution to the PM10 is 55% at BON in September 2011. The sea salt particles are therefore the main cause for the exceedances of the regulatory values of PM10 recorded at BON. The results importantly suggest that the notable PM10 concentrations measured at this urban marine site might have some but minor impact on human health.

Heterogeneous reactions of gaseous methanesulfonic acid with NaCl and sea salt particles

Methanesulfonic acid(MSA) has been identified as one of the most important intermediate products of DMS reactions in the atmosphere.Although considerable amounts of MSA have been found in the ma-rine boundary layer,little is known about the interaction of gaseous MSA with sea salt particles.To understand the fate of MSA in the atmosphere and its potential importance in atmospheric chemistry,the heterogeneous reactions of gaseous MSA with micron-scale NaCl and sea salt particles were studied using diffuse reflectance infrared Fourier transform spectrometry,X-ray photoelectron spectroscopy,and scanning electron microscopy.The CH3SO3Na and CH3SO3-were the major products of the condensed phase of the reaction of gaseous MSA with NaCl and with sea salt particles.The steady-state uptake coefficient was determined to be(5.94±2.32)×10-7(1 σ) for the reaction of gaseous MSA with NaCl particles and(2.23±1.25)×10-7(1 σ) for the reaction of gaseous MSA with sea salt parti-cles.The heterogeneous reaction of MSA with NaCl particles was found to be first-order for MSA.The reaction mechanisms were discussed.

Characteristics analysis and model prediction of sea-salt water intrusion in lower reaches of the Weihe River,Shandong Province,China

Marine sedimentary strata are widely distributed in the coastal zone of the study area, and are rich in brine resources. The exploitation of underground water resources often first caused the intrusion of salt water in the marine strata. Based on the analysis of sea-salt water intrusion feature, the sea-salt water intrusion is divided into four stages: The occurrence and development stage(1976–1985), the rapid development stage(1986–1990), the slow development stage(1990–2000) and the stable development stage(2000–2015). Based on the comparative analysis of the relationship between seawater intrusion and influencing factors, this paper presents that the groundwater exploitation and the brine resources mining are the main control factors of sea-salt water intrusion. On this basis, we have established a numerical model of the sea-salt water intrusion. Using this model, we predicted the development trend of the sea-salt water intrusion. The results show that if the current development of groundwater and brine is maintained, the sea-salt water intrusion will gradually withdraw; once development of brine stops, sea-salt water will invade again. This provides the scientific basis for the rational exploitation of groundwater and the prevention of sea-salt water intrusion.

Non-sea-salt sulfate in the marine boundary layer and its possible impact on chloride depletion

Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition in July—September 1999.The areas traversed by theexpeditionary cruises include the Arctic Ocean, the western North Pacific Ocean and the easternIndian Ocean, covering 75°N—69°S and 75°E—133°W. Aerosol samples were also taken at theChinese Zhongshan Station in East Antarctica during the CHINARE XV. Analysis of the samples yieldedconcentrations of non-sea-salt sulfate and other soluble chemical species in the marine boundarylayer. The data suggest that the chemical composition of the marine aerosols is influenced by threemajor sources: continental air masses, primary oceanic emissions, and secondary marine aerosolsoriginated from oceanic emissions.The results show that, awing to strong anthropogenic sulfuremissions from the Asian continent, non-sea-salt sulfate concentrations in the Northern Hemisphere(the western North Pacific) marine aerosol are significantly higher than those in the SouthernHemisphere (the eastern Indian Ocean). Aerosol non-sea-salt sulfate concentrations appear to beinversely correlated with aerosol non-sea-salt chloride which shows significantly negative values,indicating the loss of chloride by sea salts, in most aerosol samples. Since gaseous HCl may beinvolved in chemical reactions that deplete atmospheric ozone in the marine boundary layer (MBL),high levels of acidic non-sea-salt-sulfate released by human activities in the low and mid-latitudesof the Northern Hemisphere may become an important potential contributor to the loss of atmosphericozone in the MBL.

Heterogeneous reaction of NO_2 with sea salt particles

To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015 mol/cm3.The results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.

DISTRIBUTION FEATURES OF GIANT SEA－SALT NUCLEI IN ATMOSPHERE OVER YONGXING ISLAND， XISHA ISLANDS，DURING NORTHEAST WINTER MONSOON

In this paper, the chlorine ions nuclei data, observed at Yongxing (Xisha Islands ) during November 1987, are analyzed. The main results are: 1) The average concentration of chiorine ions nuclei with dry diameters larger than 2 μm is 878 per litre and the average salt content is 105. 4μg/m3, in which special giant nuclei with dry diameters larger than 4 μm are 19O per litre. The largest dry diameter of chloride ions observed reaches 57 μm, which are larger than that observed there during the southwest summer monsoon. The spetrum type shows quasi-unimodal and exponential lapse. 2) The salt content decreases with the height over sea surface. 3) The concentrations of chlorine ions nuclei reach the maximum value at 0800 (Local time, same below ). and minimum at 0200.

CMAS、CMAS+NaVO_(3)、CMAS+海盐作用下热障涂层的腐蚀行为与机理

环境沉积物(CaO-MgO-Al_(2)O_(3)-SiO_(2),CMAS)的高温腐蚀已成为航空发动机涡轮叶片热障涂层过早失效的重要原因之一。然而涡轮叶片工作环境复杂,熔盐、海盐常与CMAS耦合,一起对热障涂层造成多元复杂腐蚀,但目前关于CMAS与盐类的多元耦合腐蚀行为鲜有报道。针对Y2O_(3)部分稳定ZrO_(2)(YSZ)热障涂层在CMAS、CMAS+NaVO_(3)、CMAS+海盐作用下的腐蚀行为进行对比研究。通过XRD、SEM等方法对不同条件下腐蚀后的涂层进行表征,并分析热处理温度、腐蚀物种类对腐蚀行为的影响。结果表明:与CMAS相比,CMAS+NaVO_(3)、CMAS+海盐会在更低的温度下损伤涂层(1200℃)。当三种腐蚀物均能完全熔化时(1250℃),CMAS+NaVO_(3)、CMAS+海盐熔体则由于更大的流动性而大量渗入,腐蚀内部涂层。其中,CMAS+海盐熔体在涂层内的渗透性最强,1250℃热处理4 h后,渗透深度超过400μm。盐类的共存会改变CMAS的性质,增强熔体的渗透能力,增加涂层内部甚至底部失效的倾向。研究结果有助于理解盐类与CMAS耦合时混合熔体对热障涂层的破坏机理及潜在威胁。

官控层级作用下海盐聚落体系演变研究——以明清两淮盐区为例

梳理明清海盐产区官控层级由“分司-盐场-团”向“分司-盐场-灶”发展过程中各层级职能的变化,建立与官控层级对应的“分司-场治-团”和“分司-场治-市镇-生产”的聚落发展体系。从时间纵向的角度,立足官控层级重心迁移,结合经济、自然、文化等因素的变化,解析海盐聚落体系整体格局的纵横发展,总结聚落体系层级格局分布的演变规律。立足官控层级职能变迁,结合明清海盐聚落体系空间构成要素的量化分析,对海盐聚落体系层级空间形态的演变规律进行总结。研究现代东部沿海聚落体系的由来和发展过程,并为后续古代海盐手工业聚落体系的全面构建奠定基础。

Seasonal variations in aerosol compositions at Great Wall Station in Antarctica

High volume aerosol samplers at Great Wall Station in Antarctica were used to collect 73 aerosol samples between January 2012 and November 2013. The main ions in these aerosol samples, Cl^-, NO3-, SO4^2-, Na＋, K＋, Ca2＋, Mg2＋, NH4＋, as well as methane sulfonic acid, were analyzed using ion chromatography. Trace metals in these samples, including Pb, Cu, Cd, V, Zn, Fe, and Al, were determined by inductively-coupled plasma mass spectrometry. Results showed that sea salt was the main component in aerosols at Great Wall Station. Most ions exhibited significant seasonal variations, with higher concentrations in summer and autumn than in winter and spring. Variations in ions and trace metals were related to several processes（or sources）, including sea salt emission, secondary aerosol formation, and anthropogenic pollution from both local and distant sources. The sources of ions and trace metals were identified using enrichment factor, correlation, and factor analyses. Clearly, Na＋, K＋, Ca2＋, and Mg2＋were from marine sources, while Cu, Pb, Zn, and Cd were from anthropogenic pollution, and Al and V were mainly from crustal sources.

锅炉烟气加热海水的浓缩液制盐工艺研究

针对中国华电巴厘岛电厂(简称巴厘岛电厂)的特定环境,深入探讨利用锅炉高温尾气加热海水淡化系统产生的海水浓缩液,以制备海盐的可行性。研究内容涵盖了烟气特性分析、高浓度海水淡化浓缩液的性质探究,以及海盐制备工艺流程的详细设计与优化。通过综合评估该技术在巴厘岛电厂的实际应用,论证了其适用性、经济性和环境效益。研究结果表明,该工艺不仅技术上可行,而且具有显著的经济效益和环保优势,为巴厘岛电厂的能源利用与资源回收提供了新的解决方案。

渤海湾海面变化

【研究目的】海面上升,是渤海湾泥质海岸带地区全新世海陆变化最主要的影响因素。通过重建海面变化历史,有助于预测今后的变化趋势。【研究方法】全球基于实际调查的建模研究,恢复了过去数万年来较高分辨率的海面变化历史、分析了导致这种变化的各类分量的贡献。我们通过地区性相对海面变化研究,着重对地区性和区域性分量或做了定量评估、或进行了半定量推理分析,并做了具体的案例研究。【研究结果】这些研究表明,距今10~7 ka时全球海面平均上升速率是~9 mm/a,同期渤海湾西岸相对海面平均上升速率是~5.6 mm/a。这一较快的上升造成了包括渤海湾在内全球沿海平原海岸线后退(以及渤海海盆-渤海湾可能的数道沿岸堤被淹没)。但是,7 ka至今,全球与冰融水等效海面(ice-equivalent sea level,ESL)的平均上升速率降至~0.64 mm/a;5 ka以来,甚至不再上升。7 ka以来,渤海湾西岸相对上升速率是~0.46 mm/a;5.5 ka之后,进一步减弱到~0.18 mm/a。上述全球和渤海湾西岸海面变化,显示出明显的“二段式”上升特点。以~7 ka为转折点:之前与之后的上升速率相差一个数量级。对于渤海湾西岸而言,叠加在这个长达~7000年的明显减速但仍缓慢上升背景上的,是均衡掀升分量与下沉(新构造下沉+沉积自压实下沉)分量的相互抵消。于是,全球性海面的缓慢上升、区域性均衡调整造成的掀升与局地下沉,这三者的复杂博弈,形成了长达~7000年的、经常受高潮水影响的渤海湾西岸障壁岛型贝壳堤-潟湖盐沼洼地周期性交替的沿海地形地貌格局。1870 CE至今的150余年间,全球海面平均上升速率~1.7 mm/a,近10余年来更加速至3.7 mm/a,渤海湾同时期I堤海岸线向海侧的前凸岸段平均蚀退1~3 km。【结论】我们推断1870CE以来的全球气温上升-海面上升与渤海湾同时期海岸线蚀退可能具因果关系。21世纪全球变暖及因此引起海面~6~8 mm/a上升的预测,是1870 CE至今全球加速升温-海面加速上升的必然延续。从地质学角度,这将导致渤海湾今后的“可容空间”逐步增加,为海岸线-潮间带蚀退、盐沼湿地退化提供条件,从而将可能导致持续了~7000年的贝壳堤障壁岛-潟湖盐沼地貌过程的终止,转入与7 ka之前相似的海面上升加速时的沿岸堤-沿海低地模式。以上基于全球研究及渤海湾实际调查结果做出的推断,将对渤海湾泥质海岸带的中长期发展产生影响。

What Is the Convenience of Treating a Wetland as an Agricultural Area?

The Gelsari and Lentini marshes, in east-central Sicily, are wetland under heavy anthropogenic pressure. This area is regularly subjected to water withdrawals and agriculture is practiced. Periodic bird census activities had been conducted in this area between 2016 and 2022 with collected data being supplemented with the data from a previous survey conducted between 2010 and 2016. During the censuses, numerous photographs were collected, which were later used for counts. In total, 121 surveys were carried out, with visits occurring approximately 20 times per year, covering all seasons. The data collected, both from bibliography and unpublished observations, were organised in table. 120 species and subspecies have been reported, 41 of which are in Annex I of the Birds Directive. Between 2021 and 2022, a water column measurement was taken in a central area of the Lentini marsh and compared with rainfall data in the area. It was found that water removal, occurring in both marshes in different modes, produced different effects on habitat conservation. Of the two marshes, Lentini is the one in which the existing favorable conditions in its most depressed areas, located below sea level, have allowed for the adequate conservation of the wetland. This environmental improvement having occurred with respect to the previous period has restored to the marsh its historically recognized possibility of not drying up completely during the summer period, allowing permanence of numerous birds. The obtained results suggest total elimination of agriculture and discontinuation of water withdrawals in the Lentini marsh as well as regulation of withdrawals in the Gelsari marsh.

海盐阳离子对硫铝酸盐水泥性能的影响研究

本试验探究海水中常见阳离子对硫铝酸盐水泥(SAC)性能的影响规律,旨在为海工混凝土的研究及实际工程应用提供参考.根据海水中阳离子浓度配制1倍、1.5倍、2倍和2.5倍对应浓度的乙酸盐溶液作为拌和水,研究海盐阳离子种类及浓度对硫铝酸盐水泥砂浆的工作性能、物理性质、力学性能以及净浆凝结时间的影响,并通过微观试验分析水泥水化产物和微观结构.结果表明,钠离子和钙离子掺入缩短SAC凝结时间,钾离子对其凝结时间影响不大,镁离子显著延长SAC凝结时间,流动度变差.阳离子掺入降低水泥净浆孔隙率和吸水率,较高浓度倍数阳离子掺入不利于水泥砂浆的抗折强度,但有利于其抗压强度.

氯盐侵蚀作用下纳米碳酸钙对海砂混凝土结合氯离子性能的影响

考虑氯盐侵蚀时间和纳米碳酸钙(NC)的影响,研究了氯盐侵蚀作用下海砂混凝土结合氯离子性能。结果表明:随氯盐侵蚀时间增加,海砂混凝土中自由氯离子含量和结合氯离子含量均逐渐增加,掺入NC能够进一步提高海砂混凝土中结合氯离子含量;随氯盐侵蚀时间增加,海砂混凝土中Friedel's盐和水化硅酸钙(C-S-H)含量及C-S-H中钙硅物质的量比(Ca/Si比)逐渐提高;氯盐侵蚀14 d,掺NC海砂混凝土中Friedel's盐含量明显下降,其中掺1%NC使Friedel's盐含量减少最明显;海砂混凝土中掺入NC越多,C-S-H含量及C-S-H中Ca/Si比增大越明显,这有助于海砂混凝土中物理吸附氯离子。

Primary Production and the Hydrochemical Parameters of the Salt Lakes in the North-Western Part of the Crimea(Russia)

1 Introduction It is known that more than 300 lakes and lagoons are present in the Crimean Peninsula,which are divided depending on position to 7 groups:Perekop,Tarkhankut,Evpatoriyskaya,Khersonesskaya,lake on the mountainpastures,Kerch and Genicheskaya.Almost the all lakes,with the exception of the small freshwater lakes,which situated on mountain pastures of the Main ridge of

Petroleum Exploration in the Yemeni Red Sea and Offshore Area (Tihama Basin)

The Red Sea is a pericratonic upper Tertiary basin which developed on the continental margin of Arabia. It is characterized by halokinetic tectonics in the upper structural stage and block-Rifting in the lower structural stage. This margin is overprinted on a Pre-rift Mesozoic platform. Hydrocarbon exploration interest in the Yemeni Red Sea sector and Offshore area (Tihama Basin) is based on three objectives, which cross pond to stages in geotectonic evolution; Mesozoic Pre-rift targets; Miocene Syn-Rift Salt targets; and upper Miocene-Pliocene Post-rift drift sequences. Reservoirs with appropriate sealing units ( salt or shale ) have been recorded. Models of source rock maturation using observed geothermal gradients are consistent with analytical results, and prove of oil and gas generation. Most traps are described as faulted, fault-blocks, listric-faults or structural. The evaporite group mainly consists of Halite and Anhydrite, that exhibits a strong halokinesis affecting a structural style-of Infra and Intra evaporite sequences in offshore (Tihama basin ).

A method for estimating the fresh water-salt water interface with hydraulic heads in a coastal aquifer and its application

Examining the descriptions of piezometric heads at two points in both the salt water and fresh water zones reveals that when the groundwater flow system is in steady state and satisfies the Dupuit assumption, the location of the fresh water-salt water interface in a homogeneous, isotropic, and unconfined coastal aquifer can be estimated based on a piezometric head of fresh water at a point in the fresh water zone （from the water table to the interface） vertically lined up with a piezometric head of salt water at a point in the salt water zone （from the interface down）. Research shows that the new method is a general relation and that both the Hubbert relation describing the location of the interface and the Ghy- ben--Herzberg relation are special cases of this method. The method requires two piezometric wells to be close to each other and each tapping into a different zone. Measurements of piezometric heads at a well cluster consisting of piezometric wells tapping separately into fresh water and salt water zones near Beihai, China at 5-day intervals for 15 months are used to illustrate the estimation of interface location. The depth of the interface for well H5 ranges from 32 to 72 m below the sea level.

Evaluation of the Quality for the Egyptian Red Sea Coastal Waters during 2011-2013

To assess the quality of the Egyptian Red Sea coastal waters for the sustainable use and development, due to its importance for the national income, four field campaigns were annually carried out during the period from 2011-2013 to investigate the hydrography, nutrient salts, heavy metals and petroleum hydrocarbons. Except for the area of Bir Shalatein, the results of beach litter cleared out that the shoreline of the studied area is not affected by man-made litter. No sewage could be observed. The results of the present study showed that water temperature followed seasonal changes in air temperature. Red Sea water is more saline than adjacent Arabian Sea. DO revealed high values and presence of well oxygenated waters. Minor changes in the distribution of pH, BOD, DOM and COD, revealed that limited effects of human impacts and depend mainly on the dynamics of its water as well as on the geographical location. Low Chl-a and TSM concentrations and high transparency revealed that also the effect of human impacts is almost negligible. Significantly higher sea water temperatures, TSM, pH, DO, BOD, DOM, and COD were observed in summer season compared to their corresponding values in winter season. Dissolved inorganic nitrogen concentrations were quite low because there is little nutrient input from soil, agriculture and pollution on land. Based on the annual mean values, the pattern concentrations of dissolved inorganic nitrogen forms followed the order: NO3 > NH4 > NO2. The Red Sea coastal waters are classified as oligotrophic to mesotrophic state. A remarkable increase of PO4 concentration was observed in the middle Red Sea stations due to huge amounts of effluents enriched with phosphate from the main shipping and industry of Phosphate Companies. SiO4 displayed a large variability due to the supply of SiO4, which flows in the Red Sea through the strait of Bab El-Mandab, biological consumption, organic matter decomposition and the partial dissolution of quartz particle transported to the sea from the surrounding desert during sand storms. Concentrations of ammonia, phosphorus, total nitrogen, and total phosphorus were significantly higher in summer compared to their corresponding values in winter. In general, the majority of TN and TP in winter were in the form of organic-N (91.3%) and organic P (96.8%). The mean DIN/DIP ratio revealed high nitrogen concentrations in comparison with that of phosphorous and the surface coastal waters of the Red Sea are principally, P-limited for phytoplankton growth with higher values in winter season compared to summer season. Concentrations of heavy metals were quite low most probably due the absence of major local impacts of any land-based sources and/or any major negative impacts of coastal tourism. Regional variations were almost negligible and except for Mn, Cd, and Hg insignificant seasonal variations were observed. The present study revealed concentrations for metals in the acceptable levels. Furthermore, concentrations of petroleum hydrocarbons were significantly higher in winter than in summer which is mainly attributed to the increase in the rate of evaporation for petroleum hydrocarbons in summer. In general, the maximum concentration was much lower than the harmful concentrations reported for seawater. Correlation coefficients as well as principle component analysis (PCA) were applied.