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1.
Yukiyo Saitoh Kenshi Kuma Yutaka Isoda Hiroshi Kuroda Hiromi Matsuura Taku Wagawa Hyoe Takata Naoto Kobayashi Seiya Nagao Takeshi Nakatsuka 《Journal of Oceanography》2008,64(6):815-830
We report measurements of iron, nutrients, dissolved oxygen, humic-type fluorescence intensity and chlorophyll a concentrations in the coastal waters at the inflow (western) and outflow (eastern) ends of Tsugaru Strait (Japan) in June
2003 and 2004. Two different water masses (intensive eastward flow “subtropical Tsugaru Warm Current Water (TWCw)” and weak
westward flow “subarctic Oyashio Water (OW)”) were observed at the eastern end of the strait. TWCw at the southern part of
the eastern strait was vertically homogeneous with a uniform concentrations of iron (0.7–1.1 nM for labile dissolved Fe and
14–20 nM for total dissolvable Fe in 2003) as well as other chemical, biological and physical components throughout the water
column of 200 m due to strong vertical mixing in the strait. The degree of mixing in the Tsugaru Warm Current (TWC) is predominantly
affected by diurnal tidal current, which is strong during the period of tropical tides and weak during the period of equinoctial
ones. The especially strong vertical water mixing in 2003 is caused by large dissipation energy input due to the bottom friction
of passage-flow through the strait and tidal current. At the northern part of the eastern strait, the fresh surface layer
overlying the OW and the deep-bottom waters in 2003 contained large concentrations of dissolved iron, resulting from iron
supplied from river runoff and shelf sediments, respectively. These results suggest that the most important mechanism for
transporting iron in the strait is the strong vertical water mixing due to the tidal current, and that the iron sources in
the coastal waters are the organic-associated, iron-rich freshwater input into the surface water. 相似文献
2.
Vertical and horizontal distribution of fluorescent dissolved organic matter in the Southern Ocean 总被引:3,自引:0,他引:3
Youhei Yamashita Ayumi Tsukasaki Tamihito Nishida Eiichiro Tanoue 《Marine Chemistry》2007,106(3-4):498-509
The vertical and horizontal distribution of fluorescent dissolved organic matter (FDOM), determined by fluorescence intensity at 320 nm excitation and 420 nm emission, were clarified in nine stations on two transects at the Southern Ocean, including a subtropical, subantarctic, polar frontal and Antarctic zone. All vertical profiles of fluorescence intensity showed that levels were lowest in the surface waters, increased with increasing the depth in mid-depth waters ( 2000 m), and then stayed within a relatively narrow range from there to the bottom. Such vertical profiles of FDOM were similar to those of nutrients, but were adverse to dissolved oxygen. In water columns below the temperature-minimum subsurface water (dichothermal waters) in the Antarctic zone and below the winter mixed layer in the other zones, we determined the relationships of fluorescence intensity to concentrations of nutrients and apparent oxygen utilization (AOU) over the entire area of the present study, and found significant linear correlations between the levels of fluorescence intensity and nutrient concentrations (r = 0.70 and 0.71 for phosphate and nitrate + nitrite, respectively) and AOU (r = 0.91). From the strong correlation coefficient between fluorescence intensity and AOU, we concluded that FDOM in the Southern Ocean is formed in situ via the biological oxidation of organic matter. The regeneration of the nutrients/consumption of the oxygen/formation of FDOM was active in mid-depth waters. However, the correlations between fluorescence intensities and nutrients and AOU were different in the mid-depth water masses, Subantarctic Mode Water (SAMW), and Antarctic Intermediate Water (AAIW), indicating that the sources of organic matter responsible for FDOM formation were different. A considerable amount of FDOM in the SAMW is thought to be produced by the remineralization of DOM in addition to sinking particulate organic matter, while DOM is less responsible for FDOM formation in the AAIW. 相似文献
3.
P. N. Makkaveev 《Oceanology》2009,49(4):466-472
Abnormally high pH values (up to 9 NBS units and over) were registered by different expeditions at the seaward edge of the
Volga River delta. Within the report, the relationship of the pH values, the dissolved oxygen content, and the water temperature
are considered using the equations of the thermodynamic theory of carbonate equilibrium. It is shown that the changes of the
pH values are nonlinear relative to the content of oxygen. The nonlinearity is most pronounced at high values of the water
saturation with oxygen (over 110–120%). A pH value over 9 may be reached in well heated waters at a dissolved oxygen content
of 8–9 ml/l. The oxygen content as such is of course high but not excessive and might be caused by the high intensity of the
production processes in the waters. 相似文献
4.
西太平洋冬季上层水体有色溶解有机物的分布和转化特征 总被引:3,自引:1,他引:2
为深入解析西太平洋溶解有机碳的生物地球化学过程,本研究于2015年12月至2016年1月,开展了西太平洋上层水体有色溶解有机物(CDOM)吸收光谱和荧光光谱特征研究。研究结果表明,西太平洋上层水体CDOM吸收系数a(320)变化范围为0.01~1.07 m-1,平均值为0.18 m-1;其较高值位于100~200 m水层,表层的海水相对含量较低,主要以有机物的光化学分解为主。采用PARAFAC分析CDOM三维荧光光谱特征,得到1种类腐殖质组分C2(252(310 nm)/405 nm)及2种类蛋白组分C1(224(276 nm)/335 nm)和C3(224(260 nm)/300 nm),其中类腐殖质荧光组分占总荧光强度的11%~22%,蛋白质荧光组分占总荧光强度的78%~89%,蛋白质荧光中类色氨酸和类络氨酸组分对荧光强度的贡献相当。洋流在大尺度上控制西太平洋CDOM的分布特征,两流交界处和环流形成区域的CDOM相对含量较高,荧光信号较强。西太上层水体CDOM相对含量和荧光信息,与温度、盐度、DO和营养盐等理化因素之间的相关分析结果表明,CDOM主要成分类蛋白质的产生主要受上层水体初级生产过程控制。 相似文献
5.
Onega Bay waters are characterized by a high content of chromophoric dissolved organic matter (CDOM). The absorbance spectra and fluorescence intensity (excitation wavelength 455 nm, emission wavelength >680 nm) were used to assess the distribution of CDOM content in water filtered through a GF/F filter. The CDOM content at different points in Onega Bay showed more than a fourfold difference, as inferred from the measured values. The CDOM content in surface waters was, as a rule, higher than in the deeper horizons. A higher CDOM content was measured near the Onega River, near the middle part of the Onega shore, and near the Pomor shore opposite the town of Belomorsk. River runoff is the major source of CDOM in Onega Bay water. The CDOM chemical composition in Onega Bay waters was heterogeneous. The ratio of the fluorescence intensity to the absorbance value was higher near the mouths of rivers and in intensive mixing zones than in water characterized by high salinity. A highly significant linear correlation (R2 = 0.7825) between water salinity and CDOM fluorescence intensity was demonstrated. The contribution of fluorescent compounds to river runoff CDOM is substantially higher than the contribution to the composition marine CDOM. 相似文献
6.
Evidence of microphytobenthic roles on coastal shallow water of the Seto Inland Sea,Japan 总被引:1,自引:0,他引:1
This study describes the temporal variation of microphytobenthic biomass and its controlling factors, as well as the impact
of microphytobenthic activities on coastal shallow sediment in the eastern Seto Inland Sea, Japan. The chlorophyll a (Chl a), phaeopigments and sedimentary biophilic element (C, N, P and Si) contents in surface sediments, as well as nutrient concentrations
at the sediment-water interface (overlying water and pore water) were observed monthly during November 2003 to May 2005 at
one site in Shido Bay (water depth ca. 7 m) and at one site in Harima-Nada (35 m). No correlation was observed between the sedimentary biophilic elements and other
parameters. The maximum chlorophyll a content of 48.2 μg g–1 was found in surface sediments under the photon flux reaching the seafloor of 537 μmol photon m–2 s–1 during the winter period when water transparency was the highest at station S (Shido Bay). Our results suggest that higher
chlorophyll a content in surface sediment was due to the fresh microphytobenthic biomass (mainly benthic diatom). We also found a significant
negative correlation between Chl a and inorganic nutrients in pore water during the low temperature period, especially silicic acid. This result suggests that
the silicic acid was assimilated largely during the increase of microphytobenthic biomass in surface sediment. This study
suggests that the microphytobenthic roles may have a great effect on nutrient budgets during the large supply of irradiance
(winter periods) for their photosynthetic growth in shallow coastal waters. 相似文献
7.
Hiroshi Murakami Kosei Sasaoka Kohtaro Hosoda Hajime Fukushima Mitsuhiro Toratani Robert Frouin B. Greg Mitchell Mati Kahru Pierre-Yves Deschamps Dennis Clark Stephanie Flora Motoaki Kishino Sei-Ichi Saitoh Ichio Asanuma Akihiko Tanaka Hiroaki Sasaki Katsumi Yokouchi Yoko Kiyomoto Hiroaki Saito Cécile Dupouy Absornsuda Siripong Satsuki Matsumura Joji Ishizaka 《Journal of Oceanography》2006,62(3):373-393
The Global Imager (GLI) aboard the Advanced Earth Observing Satellite-II (ADEOS-II) made global observations from 2 April
2003 to 24 October 2003. In cooperation with several institutes and scientists, we obtained quality controlled match-ups between
GLI products and in-situ data, 116 for chlorophyll-a concentration (CHLA), 249 for normalized water-leaving radiance (nLw) at 443 nm, and 201 for
aerosol optical thickness at 865 nm (Tau_865) and Angstrom exponent between 520 and 865 nm (Angstrom). We evaluated the GLI
ocean color products and investigated the causes of errors using the match-ups. The median absolute percentage differences
(MedPD) between GLI and in-situ data were 14.1–35.7% for nLws at 380–565 nm, 52.5–74.8% nLws at 625–680 nm, 47.6% for Tau_865, 46.2% for Angstrom, and 46.6%
for CHLA, values that are comparable to the ocean-color products of other sensors. We found that some errors in GLI products
are correlated with observational conditions; nLw values were underestimated when nLw at 680 nm was high, CHLA was underestimated
in absorptive aerosol conditions, and Tau_865 was overestimated in sunglint regions. The error correlations indicate that
we need to improve the retrievals of the optical properties of absorptive aerosols and seawater and sea surface reflection
for further applications, including coastal monitoring and the combined use of products from multiple sensors. 相似文献
8.
HU Xupeng SU Rongguo ZOU Weiming REN Shijun WANG Hongtao CHAI Xiaoping WANG Yiming 《海洋学报(英文版)》2010,29(4):116-128
The excitation spectra of chlorophyll (Chl) fluorescence can be used to differentiate phytoplankton populations at phylum level in vivo and in situ within a few minutes.The investigated phytoplankton divisions (Dinophyta,Bacillariophyta,Chrysophyta,Cyanophyta,Cryptophyta,Chlorophyta) are each characterized by a specific composition of photosynthetic antenna pigments and,consequently,by a specific excitation spectrum of the Chl fluorescence.Norm excitation spectra (emission of 680 nm and excitation of 400–600 nm) of every division were obtained from several species per division by a F4500 fluorescence spectrophotometer.Fisher’s linear discriminant analysis of the norm spectra shows that the divisions could be discriminated.The discrimination method,established by multivariate linear regression and weighted least squares,was used to differentiate the phytoplankton samples cultured in the laboratory and samples collected from the Jiaozhao Bay at division level.The correctly discriminated samples were more than 94% for single algal species ones,more than 84% for simulatively mixed ones,more than 83% for real mixed ones and 100% for samples collected from the Jiaozhou Bay for the dominant species.The method for phytoplankton differentiation described here can be applied to routine checking by fluorescence spectrophotometer,and benefit the monitoring and supervision tasks related to phytoplankton populations in the marine environments. 相似文献
9.
A. K. Ambrosimov D. A. Ambrosimov P. N. Makkaveev Yu. R. Nalbandov L. E. Skibinskii P. V. Hlebopashev 《Oceanology》2009,49(5):630-642
Characteristics of different types of river drainage were obtained during studies of a polygon in the near-mouth part of the
Volga River in 2000–2003: “fast” (flowing through deep channels) and “slow” (that which passes through the littoral parts
of the delta (1–2 m)). The low current velocities (lower than in the channel waters by a factor of ten), the abundance of
water vegetation, and the strong heating of the waters lead to the high intensity of the biochemical processes. Therefore,
the chemical composition of the waters is subjected to significant transformation with intensity so high that it allows comparing
these regions with some sort of “bioreactor.” These changes influence the dissolved oxygen and various forms of carbon content. 相似文献
10.
The intensity of the processes of organic matter (OM) destruction in the deep-water part of the Arctic Basin is considered
in terms of the activities of hydrolytic enzymes (alkaline phosphatase and proteases) and of redox enzymes of the electron
transport system (ETS). High concentrations of mineral phosphorus are shown to cause low phosphatase activity (0.000–0.005
μM P/l h). The average time of the phosphate recycling amounted to about 240 h. The ranges of the total and specific activity
of protease are 0.000–0.192 mg of azocasein/(l h) and 0.00–3.57 mg of azocasein/h mg of protein, respectively. It is found
that the microplankton production of exo- and endopeptidase in the Arctic Basin is controlled by the concentration of nitrates
in the water. The values of the total and the specific activities of the ETS enzymes vary within 0.27–8.96 μl O2/(l h) and 8.4–583 μl O2/mg of protein h, respectively. It is shown that the maximum values of the total activities of the hydrolytic and redox enzymes
are characteristic for the photic layer. The vertical fluxes of organic carbon from the photic layer, being calculated by
the activity of the ETS enzymes, amounted to 220–600 g of Corg/year m2. The presence of ice intensifies the redox processes by factors of 2–15. 相似文献
11.
L. G. Bolshakova 《Izvestiya Atmospheric and Oceanic Physics》2009,45(6):770-778
The requirements imposed on the spectral characteristics of optical filters for portable optical ozonometers are analyzed;
when satisfied, they make it possible to determine the total atmospheric ozone to an accuracy no lower than the accuracy achieved
by complex spectral slit instruments. Considered is the dependence of the calculated ozone absorption coefficients on the
spectral characteristic of the filters and total ozone for the nonmonochromatic radiation measured with two optical filters.
Estimates of the role of contrast and permissible values of the background transmittance of filters in the range of 294.8–400
nm are presented. With these estimates taken into account, it is recommended in two-filter ozonometers to use interference
filters with a transmission maxima at 305.5–307 and 326–330 nm with a spectral width of their bands at half of the height
of the maximum transmission of 2–5 nm. 相似文献
12.
Hydrographic Structure and Transport of Intermediate Water in the Kuroshio Region off the Boso Peninsula, Japan 总被引:1,自引:1,他引:1
Kosei Komatsu Yutaka Hiroe Ichiro Yasuda Kiyoshi Kawasaki Terrence M. Joyce Frank Bahr 《Journal of Oceanography》2004,60(2):487-503
Hydrographic structure and transport of intermediate water were observed in the Kuroshio region south of Japan, focusing on
the 26.6–27.5σθ density in six cruises from May 1998 through September 2001. In the section off the Boso Peninsula where the Kuroshio exfoliates
eastward, the intermediate water was clearly clustered into three groups meridionally composed of the coastal water, the Kuroshio
water and the offshore water. Compared with the Kuroshio water characterized by warm, salty water transported by the Kuroshio,
the coastal and offshore waters significantly degenerated due to mixing with cold, fresh waters originated from the subarctic
region: the former was affected by alongshore spread of the coastal Oyashio and the latter by direct intrusion of the new
North Pacific Intermediate Water (NPIW) into the southern side of the Kuroshio current axis. Particularly the offshore water
showed higher apparent oxygen utilization (AOU) in layers deeper than 26.9σθ while it showed lower AOU in layers shallower than 26.9σθ, which indicated that colder, fresher and higher AOU water was distributed on the southeastern side of the Kuroshio in deeper
layers. In May 1998, the Oyashio-Kuroshio mixing ratio was estimated to be typically 2:8 for the offshore water on the assumption
of isopycnal mixing. Moreover, northeastward volume transport of the Kuroshio water was obtained from geostrophic velocity
fields adjusted to lowered acoustic Doppler current profiler (LADCP) data to yield 6.1 Sv at 26.6–26.9σθ and 11.8 Sv at 26.9–27.5 σθ.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
A. N. Solov’ev 《Oceanology》2006,46(3):440-445
A submersible eight-channel filter-fluorometer was constructed for the estimation of the variability of the ratio between the integral intensities of several bands of the fluorescence spectrum of dissolved organic agents in natural water excited in specified wavelength intervals. The filter-fluorometer was used to obtain three vertical profiles of the fluorescence intensity at 18 points in Kaliningrad Bay of the Baltic Sea in the spectral bands at 415, 458, and 510 nm emitted simultaneously from the water column excited by the ultraviolet radiation in the interval from 320 to 380 nm. It was shown that a pronounced (tens of times as much) relative (between the spectral bands) variability of the fluorescence allows a number of water conditions to be recognized. The correlations of the multiband fluorometric information with the biohydrochemical and ecological characteristics of the water still require clarification. 相似文献
14.
The ratio of dissolved cadmium (Cd) to phosphate (PO4) in the subtropical coastal area of Ishigaki Island, Okinawa, Japan, was investigated. Twenty vertical seawater samplings
were carried out once a month from May 2008 to January 2010. In order to examine how the Cd/PO4 ratio in seawater varies with the oceanographic conditions (i.e., the water temperature–salinity characteristics), the water
masses at the study sites were classified into two types: group 1 with a water temperature of >25°C and a salinity range of
34.0–34.4, and group 2 with a water temperature of <25°C and a salinity of >34.4. A different phytoplankton assemblage was
observed in each water mass defined. Different Cd/PO4 ratios were obtained for the two water mass types, due to the differences between the types in terms of the environmental
conditions such as the water temperature–salinity (T–S) characteristics and phytoplankton assemblages, as well as possible variations in the concentrations of dissolved iron, zinc,
manganese, and CO2 in seawater in each water mass. 相似文献
15.
Masachika Masujima Ichiro Yasuda Yutaka Hiroe Tomowo Watanabe 《Journal of Oceanography》2003,59(6):855-869
Oyashio water flowing into the Mixed Water Region (MWR) and the Kuroshio Extension region that forms North Pacific Intermediate
Water (NPIW) has been examined, based on four Conductivity-Temperature-Depth profiler (CTD)/Lowered Acoustic Doppler Current
Profiler (L-ADCP) surveys of water masses and ocean currents. There are two processes by which the Oyashio water intrudes
across the Subarctic Front (SAF): one is a direct cross-nearshore-SAF transport near Hokkaido along the western boundary,
and the other is a cross-offshore-SAF process. Seasonal variations were observed in the former process, and the transport
of the Oyashio water across SAF near Hokkaido in the density range of 26.6–27.4σθ was 5–10 Sv in spring 1998 and 2001, and 0–4 Sv in autumn 2000, mainly corresponding to the change of the southwestward Oyashio
transport. Through the latter process, 5–6 Sv of the Oyashio water was entrained across the offshore SAF from south of Hokkaido
to 150° in both spring 2001 and autumn 2000. The total cross-SAF Oyashio water transport contributing to NPIW formation is
more than 10 Sv, which is larger than previously reported values. Most of the Oyashio water formed through the former process
was transported southeastward through the Kuroshio Extension. It is suggested that the Oyashio intrusion via the latter process
feeds NPIW in the northern part of the MWR, mainly along the Subarctic Boundary and SAF.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
Tomoharu Senjyu Noriko Asano Masaji Matsuyama Takashi Ishimaru 《Journal of Oceanography》1998,54(1):29-44
Intermediate intrusion of low salinity water (LSW) into Sagami Bay was investigated on the basis of CTD data taken in Sagami
Bay and off the Boso Peninsula in 1993–1994. In October 1993, water of low temperature (<7.0°C), low salinity (<34.20 psu)
and high dissolved oxygen concentration (>3.5 ml I−1) intruded along the isopycnal surface of {ie29-1} at depths of 320–500 m from the Oshima East Channel to the center of the
bay. On the other hand, the LSW was absent in Sagami Bay in the period of September–November 1994, though it was always found
to the south off the Boso Peninsula. Salinity and dissolved oxygen distributions on relevant isopycnal surfaces and water
characteristics of LSW cores revealed that the LSW intruded from the south off the Boso Peninsula to Sagami Bay through the
Oshima East Channel. The LSW cores were distributed on the continental slope along 500–1000 m isobaths and its onshore-offshore
scales were two to three times the internal deformation radius. Initial phosphate concentrations in the LSW revealed its origin
in the northern seas. These facts suggest that the observed LSW is the submerged Oyashio Water and it flows southwestward
along the continental slope as a density current in the rotating fluid. The variation of the LSW near the center of Sagami
Bay is closely related to the Kuroshio flow path. The duration of LSW in Sagami Bay is 0.5 to 1.5 months. 相似文献
17.
A. F. Sazhin F. V. Sapozhnikov T. N. Rat’kova N. D. Romanova V. P. Shevchenko A. S. Filippov 《Oceanology》2011,51(2):295-305
The data on the supra-ice snow, ice, under-ice water, and benthic algal flora obtained in 2007–2008 by sampling in the estuary
of the Severnaya Dvina River are analyzed. The river ice and under-ice water in the estuarine zone and in the channel part
of the Severnaya Dvina differed greatly in the algal flora’s composition. The fresh water species never exceeded 8.6%, while
the ice algae composed 90–96% of the total ice inhabitants’ biomass. In the under-ice water, this value did not exceed 58–64%.
The bacteria in the ice composed not more than 2.5–10% of the total biomass, while, in the under-ice water, 36–49%. The shares
of ciliates (0.04%) and nematodes (0.005–1.6%) in the total biomass were negligible. In the estuarine zone, the ice was inhabited
mainly by nematodes (78% of the total biomass), while, in the river, their share decreased to 9%. The contribution of bacteria
was 15% in Dvina Bay and increased to 61% in the river. The importance of algae in the snow was minor: 7% of the total biomass
in the marine zone and 30% in the river region. High species diversity of the algal flora in the sandy and sandy-silty littoral
grounds was revealed. The values of the total biomass of the bottom algal flora (0.38 g C/m2) were only two to three times lower than the values revealed in similar habitats in the summer. The epipelithic forms (0.15
g C/m2) dominated, being represented by 46 species of algae (49%). The shares of epipsammonic (0.12 g C/m2) and planktonic (0.11 g C/m2) species were almost equal to each other: 25 and 22 species, respectively (27 and 24%). 相似文献
18.
On the basis of processing of the oceanographic data accumulated for the water area of the North Atlantic in 1950–1999 (∼500,000
stations), we study seasonal and interannual variations of the principal characteristics of pycnocline within the range of
σt = 25.5–27.5 conventional density units. It is shown that the interannual oscillations of these characteristics in the entire
analyzed layer can be regarded as a superposition of fluctuations with periods from 2–3 to 10–12 yr. The typical ranges of
these fluctuations for the depths of occurrence of isopycnic surfaces and the corresponding temperature and salinity are equal
to 20–25 m, 1–1.5°C, and 0.25‰, respectively. The intensification of atmospheric circulation at middle latitudes is accompanied
by the simultaneous deepening of the pycnocline and its heating in the central part of the North Subtropical Anticyclonic
Gyre. At the same time, the process of weakening of the atmospheric circulation leads to the rise of the pycnocline and its
cooling. The complete cycle of interaction of the North-Atlantic Oscillation with the anomalies of isopycnic characteristics
(with regard for the period of their advection) is equal to ∼6–8 yr.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 29–48, March–April, 2007. 相似文献
19.
This study describes the three-dimensional distributions of the Turner angle (Tu) and the potential vorticity (PV) of the
main pycnocline water in the subtropical North Pacific (10–50°N, 120°E–120°W) using a large in situ CTD data set taken by
the Argo profiling floats during June to October of 2001–2009 to clarify the detailed distribution of the central water and
the mode waters as well as the relationship between these water masses. The ventilated part of the main pycnocline water (σ
θ < 26.7 kg m−3) in the subtropical gyre generally displays a sharp peak in Tu value of 59° in the histogram. The Tu histograms for 10° × 10°
geographical boxes mostly show that the mode for the Tu value is 59° too, but they also show some regional differences, suggesting
some types of relations with the North Pacific mode waters. To further investigate this relationship, the appearance probability
density function of the central water (defined as the main pycnocline water with Tu = 56°–63°) and those of the mode waters
with PVs lower than the critical value on each isopycnal surface were analyzed. The distribution area of the central mode
water (CMW) corresponds so well with that of the central water that a direct contribution of the CMW to the formation and
maintenance of the central water is suggested. On the other hand, the distribution areas of subtropical mode water (STMW),
Eastern STMW, and transition region mode water do not correspond to that of the central water. Nevertheless, indirect contributions
of these mode waters to the formation and maintenance of the central water through salt finger type convection or diapycnal
mixing are suggested. 相似文献
20.
The shortwave radiative forcings of smoke aerosol in the cloudless atmosphere during the summer fires of 2010 in European
Russia were quantitatively estimated for the land surface and the atmospheric upper boundary from measurement data obtained
at the Zvenigorod Scientific Station of the Obukhov Institute of Atmospheric Physics (OIAP ZSS), Russian Academy of Sciences.
Variations in the temperature of the surface air layer due to the smoke-induced attenuation of incoming solar radiation were
estimated. The most intensive smoke generation in the atmosphere was observed on August 7–9, 2010, when the maximum aerosol
optical thickness amounted to more than 4.0 at a wavelength of 550 nm. In this case, the albedo of single aerosol scattering
amounted to ∼0.95–0.96 and the asymmetry factor amounted to ∼0.69–0.70. The maximum shortwave radiative forcing of aerosol
amounted to about −360 W/m2 for the land surface and almost −150 W/m2 for the atmospheric upper boundary. During the period of intensive smoke generation, the cooling of the atmospheric surface
layer over daylight hours (12 h) amounted, on average, to ∼6°C. The power character of the dependence of the shortwave radiative
forcing of aerosol for the land surface on aerosol optical thickness up to its values exceeding 4.0, which was revealed earlier
on the basis of data on aerosol optical thickness (up to 1.5) obtained at the OIAP ZSS during the summer forest and peatbog
fires of 2002 in the region of Moscow, was supported. 相似文献