On the heat budget of the Arabian Sea

This study analyzes the heat budget of the Arabian Sea using satellite-derived sea-surface temperature (SST) from 1985 to 1995 along with other data sets. For a better understanding of air–sea interaction, canonical average monthly fields representing the spatial and temporal structure of the various components of the heat balance of the Arabian Sea are constructed from up to 30 years of monthly atmospheric and oceanic data. The SST over the Arabian Sea is not uniform and continually evolves with time. Cooling occurs over most of the basin during November through January and May through July, with the greatest cooling in June and July. Warming occurs over most of the basin during the remainder of the year, with the greatest warming occurring in March and September. Results indicate that the sign of the net heat flux is strongly dependent on the location and month. The effects of net heat flux and penetrative solar radiation strongly influence the change in SST during February and are less important during August and September. Horizontal advection acts to cool the sea surface during the northeast monsoon months. During the southwest monsoon horizontal advection of surface waters warms the SST over approximately the southern half of the basin, while the advection of upwelled water from the Somalia and Oman coasts substantially cools the northern basin. The central Arabian Sea during the southwest monsoon is the only area where the change in SST is balanced by the entrainment and turbulent diffusion at the base of the mixed layer. Agreement between the temporal change in the satellite-derived SST and the change calculated from the conservation of heat equation is surprisingly good given the errors in the measured variables and the bulk formula parameters. Throughout the year, monthly results over half of the basin agree within 3°. Considering that the SST changes between 8° and 12° over the year, this means that our results explain from 62% to 75% of the change in SST over 56% of the Arabian Sea. Two major processes contribute to the discrepancy in the change in SST calculated according to the heat budget equation and the change in SST derived from satellite observations. The first is the effect of the horizontal advection term. The position of the major eddies and currents during the southwest monsoon greatly affects the change in SST due to the large gradient in temperature between the cold upwelled waters along the Somali coast to the warm waters in the interior of the basin. The second major process is the thermocline effect. In areas of shallow mixed-layer depth, high insolation and wind speeds of either less than 3 m/s or greater than 15 m/s, the bulk formulae parameterization of the surface heat fluxes is inappropriate.     

Thermal fronts and cross-frontal heat flux in the southern Huanghai Sea and the East China Sea

Synoptic features in/around thermal fronts and cross-frontal heat fluxes in the southern Huanghai./Yellow Sea and East China Sea （HES） were examined using the data collected from four airborne expendable bathythermograph surveys with horizontal approxmately 35 km and vertical 1 m（from the surface to 400 m deep） spacings. Since the fronts are strongly affected by HES current system, the synoptic thermal features in/around them represent the interaction of currents with surrounding water masses. These features can not be obtained from climatological data. The identified thermal features are listed as follows ： （ 1 ） multiple boundaries of cold water, asymmetric thermocline intrusion, locally-split front by homogeneous water of approxmately 18 ℃, and mergence of the front by the Taiwan Warm Current in/around summertime southern Cheju - Changjiang/Yangtze front and Tsushima front; （2） springtime frontal eddy-like feature around Tsushima front; （3） year-round cyclonic meandering and summertime temperature-inversion at the bottom of the surface mixed layer in Cheju - Tsushima front; and （4） multistructure of Kuroshio front. In the Kuroshio front the mean variance of vertical temperature gradient is an order of degree smaller than that in other HES fronts. The southern Cheju- Changjiang front and Cheju -Tsushima front are connected with each other in the summer with comparable cross-frontal temperature gradient. However, cross-frontal heat flux and lateral eddy diffusivity are stronger in the southern Cheju - Changjiang front. The cross-frontal heat exchange is the largest in the mixing zone between the modified Huanghai Sea bottom cold water and the Tsushima Warm Current, which is attributable to enhanced thermocline intrusions.     

安达曼海的热收支分析及其水交换研究

The characteristics of the T/S structures, water mass exchange and deep circulation in the Andaman Sea are investigated based on the simulation from a high-resolution general circulation model(MITgcm). The results show that, below 1 000 m, the water mass is saltier, warmer and more homogeneous in the Andaman Sea than that in the Bay of Bengal, attributing to the strong vertical mixing at the depth of ～1 800 m. The water mass exchange between the Andaman Sea and the Bay of Bengal goes through three major channels, which manifests itself as follows: the northern channel(Preparis Channel) is the main passage of water mass transport from the Bay of Bengal to the Andaman Sea, whereas the Middle Channel(the south of Andaman Islands and the north of Nicobar Islands) has an opposite transport; the southern channel(Great Channel) features with a four-layer water exchange which results in the least net transport among the three channels; all the transports through the three channels have an intra-annual variation with a period of half a year. At 1 000-m depth, the entire Andaman Sea is occupied by a cyclonic circulation in January and July while by an anticyclonic one in April and October. The semiannual cycle found in both the deep circulation and water mass exchange is likely associated with the downwelling eastward-propagating Kelvin waves induced by the semiannual westerly component in the equatorial Indian Ocean during intermonsoon seasons.     

Winter heat budget in the Huanghai Sea and the effect from Huanghai Warm Current (Yellow Sea Warm Current)

Four sources of surface heat flux (SHF) and the satellite remote sensing sea surface temperature (SST) data are combined to investigate the heat budget closure of the Huanghai Sea (HS) in winter. It is found that heat loss occurs all over the HS during winter and the area averaged heat content change decreases with a rate of -106 W/m². Comparing with the area averaged SHF of -150 W/m^-2 from the four SHF data sets, it can be concluded that the SHF plays a dominant role in the HS heat budget during winter. In contrast, the heat advection transported by the Huanghai Warm Current (Yellow Sea Warm Current, HWC) accounted for up to 29% of the HS heat content change. Close correlation, especially in February, between the storm events and the SST increase demonstrates that the HWC behaves strongly as a wind-driven compensation current.     

Sea ice growth at nonstationary ocean-atmosphere heat exchange

A thermodynamic model of sea snow-ice cover growth under the influence of heat flows on its upper and lower surfaces is presented. The growing is described with an extended region of phase transition (a two-phase region) with a linear temperature distribution. The temperature of the upper surface is calculated with the use of a heat-balance equation on the basis of determinable meteorological observation data. The comparison of the model results with freezing experimental data is performed.     

Climatic satellite monitoring of the external heat balance of the oceans and Black Sea

The long-wave outgoing radiation, effective cloudiness equal to the product of the total cloud amount by their optical density, and the sea-surface temperature determined from the satellites are used to determine the annual course of the components of external heat balance on the sea surface whose climatic anomalies, parallel with the meridional heat and water transfer in the ocean-atmosphere system, specify the intraannual and interannual large-scale variations of weather in different regions of the Earth. The development of these studies is connected with the progress of satellite hydrophysics because the data obtained from the space become sufficiently exact, regular, and global. The increase in the existing data array on the external heat balance of the oceans from ∼15–20 to 100 yr and more would promote the solution of the problem of oscillations of Earth's climate. We present examples of coordinated numerical analysis of the heat balance of the upper (0–100 m ) layer of the Black Sea performed on the basis of the shipborne and satellite data. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 59–75, November–December, 2007.     

Deep faults,heat flow and gas leakage in the northern Black Sea

A new heat flow map has been compiled for the Black Sea. Marine segments of interregional deep faults and marine regional deep faults have been traced in detail in the northern Black Sea. Gas seeps are situated in zones of deep faults. The potential role of these faults in the formation of gas leakage is evaluated. For the first time the spatial fault coincidence with gas release is clearly interpreted as being directly interrelated. As the gas is largely of deep origin, the seeps may be indicators of subsurface hydrocarbon accumulation.     

Age estimation of the Solomon Sea based on heat flow data

Several heat flow measurements were made during the NAT83 cruise in the central part of the Solomon Sea Basin. The average value of 87 mW/m² (2.08 HFU) calculated from these and other data indicates that the age of the Solomon Sea Basin may range from 24 to 44 Ma. This is supported by the water depth, of approximately 4,500 m, versus age relationship. There is a possibility that the Solomon Sea Basin is not a back-arc basin associated with an arc but was formerly a relatively large oceanic plate. The agreement in age from both heat flow and water depth data favors the latter hypothesis.     

Age estimation of the Solomon Sea based on heat flow data

Several heat flow measurements were made during the NAT83 cruise in the central part of the Solomon Sea Basin. The average value of 87 mW/m² (2.08 HFU) calculated from these and other data indicates that the age of the Solomon Sea Basin may range from 24 to 44 Ma. This is supported by the water depth, of approximately 4,500 m, versus age relationship. There is a possibility that the Solomon Sea Basin is not a back-arc basin associated with an arc but was formerly a relatively large oceanic plate. The agreement in age from both heat flow and water depth data favors the latter hypothesis.     

Volume and heat transports and material fluxes in the East China Sea during April 1994

INTRODUCTIONTherehavebeenmanystudiesandcomputationsonVToftheKuroshiointheEastChinaThisprojectwassupportedbytheNationalNaturalScienceFoundationofChinaundercontractNo.49476278.Asanditsvacation.Forexample,(1)basedonhydrographicobservationsatactionG(PN)f...     

LICOM模拟的南海贯穿流及其对南海上层热含量的影响

利用SODA(Simple Ocean Data Assimilation)数据、XBT(Expendable Bathythermograph)观测数据和绕岛环流理论(island rule)诊断计算结果评估了一个涡相容(eddy-permitting)全球海洋环流模式——LICOM对南海贯穿流及南海上层热含量的模拟能力,同时利用模式输出探讨了南海贯穿流对南海上层热含量的影响。NEC(North Equatorial Current)分叉的垂向结构、南海内区环流的季节和吕宋海峡体积输送的年际变化等分析结果都表明,LICOM能获取西北太平洋-印尼海域环流和南海贯穿流的合理模拟结果。模式模拟的南海上层热含量季节变化与观测及同化数据都表现出良好的一致性,尤其在南海内区。相关分析表明,吕宋海峡热输送主要控制着南海内区上层的热含量变化,两者呈显著负相关,这进一步证实了南海贯穿流作为一支冷平流调制着南海上层热含量变化的重要事实。     

New heat flow measurements in the Ulleung Basin, East Sea (Sea of Japan): relationship to local BSR depth, and implications for regional heat flow distribution

In July 2007, new marine heat flow data were collected at ten sites (HF01–10) in the central and southwestern sectors of the Ulleung Basin (East Sea or Sea of Japan) as part of regional gas hydrate research. In addition, cores were collected at five of these sites for laboratory analysis. The results show that the geothermal gradient ranged from 103–137 mK/m, and the in-situ thermal conductivity from 0.82–0.95 W/m·K. Laboratory measurements of thermal conductivity were found to deviate by as much as 40% from the in-situ measurements, despite the precautions taken to preserve the cores. Based on the in-situ conductivity, the heat flow was found to increase with water depth toward the center of the basin, ranging from 84–130 mW/m². Using a simple model, we estimated the heat flow from the depths of the BSR, and compared this with the observed heat flow. In our study area, the two sets of values were quite consistent, the observed heat flows being slightly higher than the BSR-derived ones. The evaluation of regional pre-1994 data revealed that the heat flow varied widely from 51–157 mW/m² in and around the basin. Due to a large scatter in these older data, a clear relationship between heat flow and water depth was not evident, in contrast to what would be expected for a rifted sedimentary basin. This raises the question as to whether the pre-1994 data represent the true background heat flow from the underlying basin crust since the basin opening, and/or whether they contain large measurement errors. In fact, evidence in support of the latter explanation exists. BSRs are generally found in the deep parts of the basin, and vary by only ±15 m in depth below the seafloor. From the average BSR depth, we inferred the background heat flow using a simple model, which in the case of the Ulleung Basin is approximately 120 and 80 mW/m² for 2.5 and 1 km below sea level, respectively.     

南海夏季风爆发与南海热含量异常特征的相关分析

通过利用1958—2007年SODA月平均海温资料、1958—2008年NCEP/NCAR再分析资料以及1974—2008年NOAA卫星月平均OLR资料,分析了南海季风与南海上层海洋热含量之间的可能关系,发现南海夏季风爆发早晚与前冬南海上层海洋热含量存在显著的负相关,即当冬季南海上层海洋热含量偏高(低)时,次年南海夏季风爆发早(晚)。进一步对南海夏季风爆发异常年前期及前冬南海东部热含量异常年的相关大气环流特征分析后发现,南海夏季风爆发偏早和偏晚年前期的OLR特征、对流层环流特征及位势高度场分别与前冬南海东部热含量异常偏高和偏低年相一致。得出冬季南海东部热含量偏高(低)时,OLR在赤道东印度洋至我国南海及菲律宾以东为负(正)距平,南海地区对流加强(减弱);在纬向方向上,大气环流特征表现为正(负)的Walker距平环流,低纬Walker环流发展(减弱);在经向方向上,南海地区南北向局地Hadley环流加强(减弱);次年初春(3—4月)500hPa位势高度场在西太平洋副热带高压区总体为负(正)距平,副热带高压偏弱(强)。因此有(不)利于南海夏季风的早爆发。南海和西太平洋暖池区热含量异常都通过对流作用影响其上空大尺度...     

On the features of the SST annual cycle and surface heat budget in the South China Sea

The annual cycle in the ocean and atmosPhere system 15 the important signal of the climatic variabilities.Observed studies had indicated that the seasonal feature of the climatic system which 15 of an annual period 15 due to the seasonal variation of the solar radiation.Funher researches has shown that the formation and maintenance of the annual cycle of the thermal condition(situation)in the upper oceans are the results of both dynamical and thermal processes which both are involved in air-sea interaction.Since researches on the large-scale air-sea interaction were Propoed,sea surface temperature(SST)has always been the primary object to observe,study and predict by the scientists.     

Surface heat fluxes and subsurface heat content at a site over the southeastern Bering Sea shelf, May–July 1996

Observations from a surface mooring, in a weak-flow regime over the southeastern Bering Sea shelf, were used to derive surface heat fluxes for the period May–July 1996. Changes in heat content of the water column also were determined from subsurface temperature measurements. Agreement of net surface heat flux and change in heat content was within 2%. This result provides additional evidence that heat advection and diffusion are small in this region.     

东海与邻近海域水、热、盐通量的季节变化研究

本文基于高分辨率的区域海洋数值模式对东海及邻近海域进行温、盐、流的数值模拟,模拟结果与实测结果拟合较好。结果表明:东海与邻近海域的水交换过程具有显著的季节变化特征。从流量的角度看,台湾海峡、台湾-西表岛之间水道和西表岛-冲绳岛之间水道是外海水流入东海的3个主要水道,而冲绳岛-奄美大岛、吐噶喇海峡、大隅海峡、济州岛东部和黄东海断面是海水流出东海的水道;其年平均体积输运值分别为1.06×106 m3/s、20.49×106 m3/s、3.20×106 m3/s、-0.92×106 m3/s、-20.59×106 m3/s、-0.30×106 m3/s、-2.37×106 m3/s和-0.37×106 m3/s（向内为正）。对比发现,东海与邻近海域之间各水道的体积、热量和盐量输运均具有相似的季节变化趋势,其最大值往往出现在夏季（7月或8月）,最小值往往出现在冬季（1月或2月）。从7月到11月整个东海是流量净流出的过程,而从12月到翌年6月是流量净流入的过程,全年流量基本上保持平衡状态。东海终年存在向黄海的净输入,其体积、热量和盐量的年平均输运值分别为0.37×106 m3/s,0.027×1015 W和12.7×106 kg/s。     

The seasonal variability of an air-sea heat flux in the northern South China Sea

The seasonal variabilities of a latent-heat flux (LHF), a sensible-heat flux (SHF) and net surface heat flux are examined in the northern South China Sea (NSCS), including their spatial characteristics, using the in situ data collected by ship from 2006 to 2007. The spatial distribution of LHF in the NSCS is mostly controlled by wind in summer and autumn owing to the lower vertical gradient of air humidity, but is influenced by both wind and near-surface air humidity vertical gradient in spring and winter. The largest area-averaged LHF is in autumn, with the value of 197.25 W/m 2 , followed by that in winter; the third and the forth are in summer and spring, respectively. The net heat flux is positive in spring and summer, so the NSCS absorbs heat; and the solar shortwave radiation plays the most important role in the surface heat budget. In autumn and winter, the net heat flux is negative in most of the observation region, so the NSCS loses heat; and the LHF plays the most important role in the surface heat budget. The net heating is mainly a result of the offsetting between heating due to the shortwave radiation and cooling due to the LHF and the upward (outgoing) long wave radiation, since the role of SHF is negligible. The ratio of the magnitudes of the three terms (shortwave radiation to LHF to long-wave radiation) averaged over the entire year is roughly 3:2:1, and the role of SHF is the smallest.     

Expression of heat shock protein 70 in a permanent cell line (EPC) exposed to sediment extracts from the North Sea and the Baltic Sea

Heat shock proteins 70 (hsp70) are known to be induced by a great variety of chemical stressors. The effects of different environmental contaminants, which were identified in sediments of the North Sea and the Baltic Sea as main contaminants or as contaminants of special toxicological interest, on the extent of expression of hsp70 in a permanent cell line Epithelioma papulosum cyprini (EPC) were investigated. Concentrations of the single contaminants leading to elevated hsp70 levels were compared to the respective concentrations of these contaminants encountered in the sediment extracts thus allowing an assessment of their contribution to the toxicity of these sediments. Analysis of hsp70 was performed using western blotting techniques with subsequent comparative quantification by densitometry. Eleven of thirteen contaminants have shown a dose-dependent increase in hsp70 levels. An expression of hsp70 was observed in most cases between 0.1 and 10 microg/mL test solution. Some of the investigated stressors led to extremely high hsp70 contents even at low concentrations. However, in most cases contaminant concentrations in sediments were too low to cause an effect. For this reason, effects of the tested sediments are attributed to other contaminants or rather to mixtures of stressors.     

Thermal structure of the crust in the Black Sea: comparative analysis of magnetic and heat flow data

This paper presents the first study of mapping of the Curie point depth (CPD) from magnetic data for the Black Sea and a comparison with a classical thermal modeling from heat flow data. The provided relationship between radially averaged power spectrum of the magnetic anomalies and the depths to the magnetic sources of the Black Sea vary from 22 to 36 km. Deepening of CPDs observed in the western and eastern Black Sea basins correspond with the thickest sediment areas, whereas the shallow CPDs are related to the Mid-Black Sea Ridge and thin sediment areas at the costal side of the Black Sea. For comparison, the temperature field was also modeled from heat flow data from the Black Sea along three approximately north–south directed profiles corresponding to known DSS soundings. The Curie isotherm along the profiles occurs at depths of 22–35 km. A comparison of the results of the two independent methods reveals only 8–10 % discrepancy. This discrepancy is equal to an accuracy of temperature determination from heat flow data.     

南海地区潜热输送与我国东南部夏季降水的遥相关分析

使用奇异值分解(SVD)和经验正交函数展开(EOF)方法,分析了我国东南部夏季降水与前期(冬季、春季)及同期(夏季)南海潜热输送之间相关场的分布型,从中找出遥相关的“关键区”,并对找到的高相关区的可靠性进行了讨论。结果表明,我国东南部夏季降水与前期(冬季、春季)及同期(夏季)南海潜热输送相关密切,尤其春、夏季潜热输送与降水相关程度更高。前期中的冬季,南海北部潜热输送与华南及其近海地区的夏季降水有较显着的负相关关系;春季,南海中部海盆地带的游热输送与长江以南至华南沿海地区的夏季降水有较强的正相关关系;夏季,南海中部海盆地带仍是影响同期华南降水的“关键区”.