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1.
New experimental data that make it possible to explain and predict the observed variability of turbulent-energy dissipation in the upper ocean are discussed. For this purpose, the dependence of the energy dissipation rate of breaking wind waves on their propagation velocity (see [1]) is used. The turbulent-energy dissipation values obtained earlier in [2, 3] by a direct method are compared to the results of radar measurements of individual breaking events presented in [1]. On the basis of this comparison, a strong dependence of the turbulent-energy dissipation value on the stage of wind-wave development, which is characterized by the ratio U a /c p (U a is the wind speed and c p is the phase speed of the peak of the wind-wave spectrum) is confirmed. This dependence was found earlier purely empirically. Moreover, it is shown that the theoretically obtained dependence (c p /U a )4, does not contradict the available empirical data. The results of this study opens possibilities for scientifically substantiated calculations of greenhouse-gas exchange (specifically, CO2 exchange between the ocean and the atmosphere).  相似文献   

2.
Instead of approximation formula ln(E(t)/E(0)) = [(a ? bt)t/(c + T)] commonly used at present for representing dependence of pressure of saturated streams of liquid water E upon temperature we suggested new approximation formula of greater accuracy in the form ln(E(t)/E(0)) = [(A ? Bt + Ct 2)t/T], where t and T are temperature in °C and K respectively. For this formula with parameters A = 19.846, B = 8.97 × 10?3, C = 1.248 × 10?5 and E(0) = 6.1121 GPa with ITS-90 temperature scale and for temperature range from 0°C to 110°C relative difference of approximation applying six parameter formula by W. Wagner and A. Pruß 2002, developed for positive temperatures, is less than 0.005%, that is approximately 15 times less than accuracy obtained with the firs formula. Increase of temperature range results in relative difference increasing, but for even temperature range from 0°C to 220°C it does not higher than 0.1%. For negative temperatures relative difference between our formula and a formula of D. M. Murphy and T. Koop, 2005, is less than 0.1% for temperatures higher than ?25°C. This paper also presents values of coefficients for approximation of Goff and Grach formula recommended by IMO. The procedure of finding dew point T d for known water steam pressure e n based on our formula adds up to solving an algebraic equation of a third degree, which coefficients are presented in this paper. For simplifying this procedure this paper also includes approximation ratio applying a coefficient A noted above, in the form T d (e n ) = \(\frac{{AT_0 }}{{A - \varepsilon }}\) + 0.0866?2 + 0.0116?10/3, where ? = ln(e n /E(T 0)). Error of dew point recovery in this ratio is less than 0.005 K within the range from 0 to 50°C.  相似文献   

3.
The paper presents a new model of electronic-vibrational kinetics of the products of ozone and molecular oxygen photodissociation in the terrestrial middle atmosphere. The model includes 45 excited states of the oxygen molecules O2(b 1, Σ g + ,v= 0−2), O2 (a 1Δ g , v= 0−5), and O2(X 3Σ g − , v= 1−35) and of the metastable atom O (1 D) and over 100 aeronomic reactions. The model takes into account the dependence of quantum yields of the production of O2(a 1Δ g , v= 0−5) in a singlet channel of ozone photolysis in the Hartley band on the wavelength of photolytic emission. Taking account of the electronic-vibrational kinetics is important in retrieval of the vertical profiles of ozone concentration from measured intensities of the Atm and IR Atm emissions of the oxygen bands above 65 km and leads to an increase in the ozone concentration retrieved from the 1.27-μm emission, in contrast to the previous model of pure electronic kinetics. Sensitivity analysis of the new model is made for variations in the concentrations of atmospheric constituents ([O2], [N2], [O(3P)], [O3], [CO2]), the gas temperature, rate constants of the reactions, and quantum yields of the reaction products. A group of reactions that most strongly affect the uncertainty of ozone retrieval from measured intensities of atmospheric emissions of molecular oxygen O2(b 1Σ g + , v) and O2(a 1Δ g , v) has been determined. Original Russian Text ? V.A. Yankovsky, V.A. Kuleshov, R.O. Manuilova, A.O. Semenov, 2007, published in Izvestiya AN. Fizika Atmosfery i Okeana, 2007, Vol. 43, No. 4, pp. 557–569.  相似文献   

4.
To date no analytical solution of the pile ultimate lateral capacity for the general c–φ soil has been obtained. In the present study, a new dimensionless embedded ratio was proposed and the analytical solutions of ultimate lateral capacity and rotation center of rigid pile in c–φ soils were obtained. The results showed that both the dimensionless ultimate lateral capacity and dimensionless rotation center were the univariate functions of the embedded ratio. Also, the ultimate lateral capacity in the c–φ soil was the combination of the ultimate lateral capacity (f c ) in the clay, and the ultimate lateral capacity (f φ ) in the sand. Therefore, the Broms chart for clay, solution for clay (φ=0) put forward by Poulos and Davis, solution for sand (c=0) obtained by Petrasovits and Awad, and Kondner’s ultimate bending moment were all proven to be the special cases of the general solution in the present study. A comparison of the field and laboratory tests in 93 cases showed that the average ratios of the theoretical values to the experimental value ranged from 0.85 to 1.15. Also, the theoretical values displayed a good agreement with the test values.  相似文献   

5.
Production parameters of surface phytoplankton were measured along three transects: La Manche-Cape Town (I); Cape Town-54°S (II); 0°-49°W (along 54°S) (III). The Canary upwelling waters were most productive along transect I, where the surface chlorophyll a (Chl 0) and the surface primary production (PP 0) were as high as 4.3 mg/m3 and 173 mg C/m3 per day, respectively. Mosaic patterns in the distribution of these parameters were recorded in the northeastern regions of the South Subtropical Anticyclonic Gyre (Chl 0 = 0.03–0.35 mg/m3; PP 0 = 1.6–12.6 mg C/m3 per day). Along transect II, the average twofold southward increase in Chl 0 (from 0.2 to 0.4 mg/m3) and the concurrent decline of the phytoplankton assimilation activity ( AN 0) resulted in deviations from typical latitudinal changes inPP 0. At most sites, PP 0 values varied between 6 and 15 mg C/m3 per day. Negligible changes in Chl 0 (0.36–0.85 mg/m3), PP 0 (8–19 mg C/m3 per day), and AN 0 (0.7–1.6 mg C/mg chl a per hour) were registered for the oceanic waters along transect III. Along all the transects, PP 0 depended on Chl 0 to a greater extent than AN 0. The values of the latter parameter were largely determined by the water temperature and showed a slight correlation with the insolation. Along transect II, the integrated primary production (PP int) and the layer-integrated chlorophyll a in the upper 200 m (Chl 0–200) generally varied from 180 to 360 mg C/m2 per day and from 30 to 70 mg/m2, respectively. In the Polar Front region, an increase in Chl 0–200, PP int, Chl 0, and PP 0 up to respective values of 190 mg/m2, 520 mg C/m2 per day, 1.2 mg/m3, and 32 mg C/m3 per day was observed. A comparison of the water column (0–100 m) stability with the vertical distribution of the primary production and chlorophyll content along transect II implies that the thick (>100 m) upper mixed layer (UML) formed in response to the strong water cooling and wind forcing was largely responsible for the limited primary production in the Subantarctic and Antarctic regions. The large UML thickness resulted in an intense removal of plant cells from the photosynthetic layer and light starvation of a significant (up to 60%) part of the phytoplankton community.  相似文献   

6.
The possibility of estimating the parameters of surface pulsed sources from data on acoustic waves recorded in the atmosphere is studied. Experimental values are given for peak pressure P + of recorded acoustic signals, wave-profile area S + in their positive phase, and length t + of this phase, and the approximations of these parameters are obtained within wide ranges of source energy 10–3 < E < 1010 kg TNT and scaled distances 1 < R/E 1/3 < 4 × 104 m/kg1/3. Conventional methods of estimating the acoustic energy E according to data obtained from acoustic measurements in the atmosphere are analyzed, and ways to improve their accuracy are proposed. The influence of the type of explosions on the parameters P +, S +, and t + of acoustic signals at long distances R/E 1/3 > 500 m/kg1/3 from explosions is shown.  相似文献   

7.
The species composition, phytoplankton abundance, and relative yield of the variable fluorescence (F v /F m ) were determined in the mesotrophic Nhatrang Bay in October–November of 2004. The species diversity (250 taxonomic units) and heterogeneity of the phytoplankton structure were high. With respect to the number of species and their abundance, diatoms prevailed. In selected parts of the bay, dinoflagellates dominated. The mean biomass in the water column under 1 m2 (B t ) varied from 2.3 to 64.4 mg C/m3 being 31.0 mg C/m3 on average. The values of B t were the lowest at the stations nearest to the river mouth. Seaward, B t increased. The values of B t increased with depth at some stations and decreased at others. In the surface sea layers, the biomass was lower than that in the underlying waters. The values of F v /F m ranged from 0.10 to 0.64 (at a mean value of 0.49). The lowest values of F v /F m were observed in the area close to the seaport. Over the greater part of the bay, the values of F v /F m were higher than 0.47. Such values are indicative of the relatively high potential photosynthetic activity of the phytoplankton. The abundance and species diversity were higher than those in the dry season (March–April).  相似文献   

8.
The age and growth of filefish, Thamnaconus modestus (Günther 1877) in the southern waters of Korea were investigated. Samples were collected with commercial trawl catches during the period from May 2009 to December 2011. Of the 2,626 specimens collected, the sex ratio was not significantly different from 1:1 (P > 0.05). The total length ranged from 11.3 to 42.1 cm. The gonadosomatic index for both sexes was the highest in May to June, indicating that May to June is the main spawning period. The length of females at sexual maturity was 25.92 cm. The length-weight relationship of the filefish was TW = 0.0121TL3.0536 (n = 1,692, r2 = 0.9034, P < 0.001). The age of the sampled individuals was estimated by counting growth rings recorded on the 5th vertebrae; ages ranged from 0 to 9 years. The filefish of the same age displayed a high individual variation in total length. Length-at-age data were fitted by using the Von Bertalanffy growth model. The estimated Von Bertalanffy growth parameters were L∞ = 42.04 cm, k = 0.21 year?1 and t0 = ?1.56 for females, L∞ = 41.20 cm, k = 0.18 year?1 and t0 = ?2.36 for males, and L∞ = 43.16 cm, k = 0.17 year?1 and t0 = ?2.18 for the combination of both male and female. These data can be used as useful biological information for the future fishery management of filefish resources in Korean waters.  相似文献   

9.
C波段紧缩极化SAR海冰探测能力评估   总被引：1，自引：0，他引：1  
The C-band synthetic aperture radar(SAR) data from the Bohai Sea of China, the Labrador Sea in the Arctic and the Weddell Sea in the Antarctic are used to analyze and discuss the sea ice full polarimetric information reconstruction ability under compact polarimetric modes. The type of compact polarimetric mode which has the highest reconstructed accuracy is analyzed, along with the performance impact of the reconstructed pseudo quad-pol SAR data on the sea ice detection and sea ice classification. According to the assessment and analysis, it is recommended to adopt the CTLR mode for reconstructing the polarimetric parameters σ_(HH)~0,σ_(VV)~0, H and α,while for reconstructing the polarimetric parameters σ_(HV)~0, ρ_(H-V), λ_1 and λ_2, it is recommended to use the π/4 mode.Moreover, it is recommended to use the π/4 mode in studying the action effects between the electromagnetic waves and sea ice, but it is recommended to use the CTLR mode for studying the sea ice classification.  相似文献   

10.
河口有色溶解有机物（colored dissolved organic matter,CDOM）的分布是各种物理-生物地球化学过程共同作用的结果。为实现河口高动态变化CDOM的监测,遥感是一种重要的手段。由珠江口四个不同季节的航次获得的实测数据,本文构建了一个遥感算法以反演CDOM在400 nm的吸收系数（aCDOM （400））。该算法使用以波段反射率比值Rrs （667）/Rrs （443）和Rrs （748）/Rrs （412）为自变量。将构建的算法应用于2002-2014年的MODIS/Aqua数据,本文计算了珠江口不同季节的aCDOM （400）气候态分布。CDOM的分布主要受珠江径流量和区域水下地形特征的影响。沿着垂直于水深梯度的断面,气候态aCDOM （400）呈指数减少（y=aebx,b<0）,但不同季节差异很大。珠江口CDOM主要是河流淡水输运而来。其中,富里酸比例随盐度的增加而降低。基于构建的算法、CDOM保守混合方程和径流量,本文由MODIS/Aqua数据进一步估算了2002-2014年夏季和冬季珠江DOC的有效入海浓度和有效入海通量。珠江的有效入海浓度和有效入海通量都与流量存在正相关关系,且在夏季的相关性更明显,R2分别为0.698和0.9657。  相似文献   

11.
Results obtained from simulating the propagation of infrasonic waves from the Chelyabinsk meteoroid explosion observed on February 15, 2013, are given. The pseudodifferential parabolic equation (PDPE) method has been used for calculations. Data on infrasonic waves recorded at the IS31 station (Aktyubinsk, Kazakhstan), located 542.7 km from the likely location of the explosion, have been analyzed. Six infrasonic arrivals (isolated clearly defined pulse signals) were recorded. It is shown that the first “fast” arrival (F) corresponds to the propagation of infrasound in a surface acoustic waveguide. The rest of the arrivals (T1–T5) are thermospheric. The agreement between the results of calculations based on the PDPE method and experimental data is satisfactory. The energy E of the explosion has been estimated using two methods. One of these methods is based on the law of conservation of the acoustic pulse I, which is a product of the wave profile area S/2 of the signal under analysis and the distance to its source E I [kt] = 1.38 × 10–10 (I [kg/s])1.482. The other method is based on the relation between the energy of explosion and the dominant period T of recorded signal E T [kt] = 1.02 × (T [s]2/σ)3/2, where σ is the dimensionless distance determining the degree of nonlinear effects during the propagation of sound along ray trajectories. According to the data, the explosion energy E I,T ranges from 1.87 to 32 kt TNT.  相似文献   

12.
The current study was carried out from May 2014 to April 2015 to estimate the stock status of P. viridis in Marudu Bay. The gonad development was monitored by histological examination, while the population parameters including asymptotic length (L∞), growth coefficient (K), mortality rate (Z, F and M), exploitation level (E) and recruitment of P. viridis were estimated using the lengthfrequency data. Results of the current study demonstrated that P. viridis in Marudu Bay spawned throughout the year with two major peaks, one in April to May and another one in October to December. The recruitment pattern was continuous with the peak in May to June 2014, which corresponded to the first spawning peak in April. However, no significant recruitment was observed from the second spawning peak due to the difference in spawning timing between male and female populations. The estimated asymptotic length (L∞), growth coefficient (K), total mortality (Z), natural mortality (M), fishing mortality (F) and growth performance (ф) of P. viridis in Marudu Bay were estimate to be 117 mm, 0.97 yr-1, 4.39 yr-1, 1.23 yr-1, 3.16 yr-1 and 4.123, respectively. The exponent b of the lengthweight relationship was 2.4 and exploitation level (E) was 0.72. The high mortality, low condition indices and negative allometric of P. viridis in Marudu Bay is caused by a lack of suitable food in the surrounding water.  相似文献   

13.
The spatiotemporal variability of equatorial Pacific upper ocean heat content (HC) and subsurface heat during two types of El Niño-Southern Oscillation (ENSO), namely eastern and central Pacific (EP and CP) types, is investigated using subsurface ocean heat budget analysis. Results show that HC tendencies during both types of ENSO are mainly controlled by oceanic heat advection beneath the mixed layer to the thermocline, and the role of net surface heat flux can be neglected. The most important three terms are the zonal and vertical advections of anomalous heat by climatological currents (QU 0 T′, QW 0 T′) and zonal advection of climatological heat by anomalous current (QU′T 0). The large contribution of QU 0 T′ extends from west to east along the equatorial Pacific. The considerable contribution of QU′T 0 is confined to the east of 160°W, and that of the QW 0 T′ is observed in the central Pacific between 180°E and 120°W. In particular, a major contribution of QW 0 T′ is also observed in the far eastern Pacific east of 100°W during EP ENSO. There is also a small contribution from meridional advection of climatological heat by anomalous current (QV′T 0). In contrast, the meridional advection of anomalous heat by climatological currents (QV 0 T′) and vertical advection of climatological heat by anomalous current (QW′T 0) are two damping factors in the HC tendency, with the former dominating. Differences in spatial distribution of the heat advection associated with the two types of ENSO are also presented. We define a warm water heat index (WWH) as integrated heat content above 26 kg m?3 potential density (26σ ? ) isopycnal depth within 130°E–80°W and 5°S–5°N. Further examination suggests that the recharge–discharge of WWH is involved in both types of El Niño, though with some differences. First, it takes about 42 (55) months for the evolution of a recharge–discharge cycle during an EP (CP) ENSO. Second, the EP El Niño event peaks during the discharge phase, 7–8 months after the recharge time. The CP El Niño peaks during the recharge phase, 4–5 months before the recharge time. The locations of HC anomalies in the El Niño mature phase relative to those at recharged time explain why the EP and CP El Niño peak in different stages of the recharge–discharge process.  相似文献   

14.
为节约成本和样品,一些学者同时分析海洋沉积物中的碳、氮及其同位素（TOC、TN、δ13C和δ15N）。分析沉积物中的δ13C,需要对样品进行酸化去除无机碳,但是这一酸化过程会使TN和δ15N的分析结果产生偏差,且偏差范围与沉积物中无机碳含量（CaCO3）有关。本研究选取了低CaCO3含量（1-16%）和高CaCO3含量（20-40%）的海洋沉积物样品,比较了酸化过程对TN和δ15N的影响。研究结果表明,酸化过程对海洋沉积物中TN和δ15N的分析结果产生了显著影响。对于低CaCO3含量的样品,酸化导致样品中TN流失了约0-40%,δ15N偏移了约0-2‰;而对于高CaCO3含量的样品,酸化导致样品中TN流失了约10-60%,δ15N偏移了约1-14‰。表明酸化对TN和δ15N的影响已经超过了仪器的误差范围0.002%（TN）和0.08‰（δ15N）,将影响TN和δ15N的环境指示意义。因此,即使海洋沉积物样品中CaCO3含量很低,也必须用原样分析TN和δ15N以避免酸化过程的影响。  相似文献   

15.
The estimated characteristics of the atmospheric boundary layer, obtained by the simulation of wind wave fields using three versions of the WAM numerical model are compared with the well-known empirical dependences of drag coefficient C d on wind speed U 10 and wave age A, as well as with the dependence of dimensionless roughness height z n on inverse wave age u*/с р. Calculations carried out for several years in the areas of the Pacific and Indian oceans, based on the ERA-interim and CFSR wind reanalyses have shown good agreement between the model and empirical dependences C d (U 10) and C d (A). The range of estimated variability for z n (u*/с р ) has been found to be significantly less than empirical. It has been also found that estimated values of wind speed U 10W (t) are overestimated from 5 to 10% in all versions of WAM models compared with the input wind reanalysis U 10R (t) at the moments of appearance maximum values of wind U 10R (t). The reasons for the established features of the WAM model and their dependence on the model version are discussed.  相似文献   

16.
To explore the effects of temperature changes on dinoflagellate bloom succession in the coastal waters of the East China Sea, changes in the growth, photophysiology, and Rubisco gene expression of Prorocentrum donghaiense and Karenia mikimotoi, two harmful algal species, were investigated at different temperatures (16 to 28°C). The maximal specific growth rate and the maximal mRNA expression of Rubisco gene in P. donghaiense and K. mikimotoi occurred at 20 and 24°C, respectively. The photosynthetic activity of P. donghaiense was generally stable, but K. mikimotoi photosynthesis increased when temperatures rose from 16 to 28°C. The effective photochemical efficiency (F q ′ /F m ′ ) and the maximal relative electron transfer rate (rETRmax) of K. mikimotoi increased significantly with increasing temperature, and the lowest and highest values occurred at 16 and 28°C, respectively. It seems that P. donghaiense has higher photosynthetic capacity than K. mikimotoi due to its higher F q ′ /F m ′ , rETRmax, and photosynthetic efficiency (α). However, K. mikimotoi has a higher growth rate than P. donghaiense. These results suggest that the photosynthetic activity and genetic responses of dinoflagellates are species-dependent. It is likely that temperature changes affect species composition during blooms, leading to the observed patterns of bloom succession.  相似文献   

17.
The atmospheric effect on the characteristics of infrasonic signals from explosions has been studied. New methods have been proposed to remotely estimate the energy of explosions using the data of infrasonic wave registration. One method is based on the law of conservation of acoustic pulse I, which is equal to the product of the wave profile area S/2 of the studied infrasonic signal and the distance to the source EI [kt] = 1.38 × 10–10 (I [kg/s])1.482. The second method is based on the relationship between the explosion energy and the dominant period T of the recorded signal, EТ [kt] =1.02 × (Т [s]2/σ)3/2, where σ is a dimensionless distance used for determining the degree of manifestation of nonlinear effects in the propagation of sound along ray trajectories. When compared to the conventional EW (Whitaker’s) relation, the advantage of the EI relation is that it can be used for pulsed sources located at an arbitrary height over the land surface and having an arbitrary form of the initial-pulse profile and for any type of infrasonic arrivals. A distinctive feature of the expression for EТ is that the atmospheric effect on the characteristics of recorded infrasonic signals is explicitly taken into account. These methods have been tested using infrasonic data recorded at a distance of 322 km from the sources (30 explosions caused by a fire that occurred at the Pugachevo armory in Udmurtia on June 2, 2011). For the same explosion, empirical relations have been found between energy values obtained by different methods: EI = 1.107 × E W , E Т = 2.201 × E I .  相似文献   

18.
This study presents in situ evidence for the blooms of Trichodesmium erythraeum observed in the shelf waters of the South Eastern Arabian Sea (SEAS) during the onset of the southwest monsoon in June 2009. Evidence showed that water surface discoloration was caused by the accumulation of T. erythraeum, and that the water column contained a colony of T. thiebautii. The surface water color in the bloom region varied from pale brown to pinkish red. Pale brown indicated healthy algae at the peak of its photosynthetic activity, while pinkish red indicated the presence of photosynthetically less active filaments. Zooplankton abundance, especially copepodites, in the bloom area substantiated the theory that Trichodesmium filaments are excellent epiphytes to which the copepodites cling. The bloom area was very fertile with copious quantities of dissolved oxygen (6.85 ml L?1), PO4-P (0.108 μmol L?1) and SiO4 (1.29 μmol L?1). Lower NO3-N (0.028 μmol L?1) values in the bloom area did not appear to affect Trichodesmium growth from molecular nitrogen fixation. However, lower NO3-N values altered the normal phytoplankton composition of this area.  相似文献   

19.
Fast repetition rate fluorometry (FRRf) provides a potential means to examine marine primary productivity; however, FRRf-based productivity estimations require knowledge of the electron requirement (K) for carbon (C) uptake (K C) to scale an electron transfer rate (ETR) to the CO2 uptake rate. Most previous studies have derived K C from parallel measurements of ETR and CO2 uptake over relatively short incubations, with few from longer-term daily-integrated periods. Here we determined K C by comparing depth-specific, daily ETRs and CO2-uptake rates obtained from 24-h on-deck incubation experiments undertaken on seven cruises in Ariake Bay, Japan, from 2008 to 2010. The purpose of this study was to determine the extent of variability of K C and to what extent this variability could be reconciled with the prevailing environmental conditions and ultimately to develop a method for determining net primary productivity (NPP) based on FRRf measurements. Both daily ETR and K C of the upper layer varied considerably, from 0.5 to 115.7 mmol e? mg Chl-a ?1 day?1 and 4.1–26.6 mol e? (mol C)?1, respectively, throughout the entire data set. Multivariate analysis revealed a strong correlation between daily photosynthetically active radiation (PAR) and K C (r 2 = 0.94). A simple PAR-dependent relationship derived from the data set was used for generating K C, and this relationship was validated by comparing the FRRf-predicted NPP with the 13C uptake measured in 2007. These new observations demonstrate the potential application of FRRf for estimating regional NPP from ETR.  相似文献   

20.
Parametrization of turbulent fluxes over inhomogeneous landscapes   总被引：1，自引：0，他引：1  
Reasons for the nonclosure of the heat balance in the atmospheric boundary layers over natural land surfaces are analyzed. Results of measuring the heat-balance components over different land surfaces are used. The Cabauw (Netherlands) data (obtained throughout 1996 over a grass surface with intermittent shrubs and single trees) and the data from the Anchor station in Germany (measured over coniferous forest in 2000–2001) are analyzed. In all, the analysis involves about fifty thousand independent values of the heat-balance components measured in the experiments, which should be indicative of the reliability of the results obtained in the paper. The data have shown that the heat balance is not closed and the imbalance is 50–250 W/m2. The sum of the latent and sensible heat fluxes λE + H = STF is found to be systematically smaller than the difference between the net radiation and the heat flux into the ground R n ? G. It is shown that the main cause of a systematic heat imbalance in the atmospheric boundary layers over inhomogeneous land surfaces is that the methods of surface-flux measurement and estimation are based on the theory that requires the hypothesis of stationarity and horizontal homogeneity. Direct data analysis has shown that the heat imbalance increases with landscape inhomogeneity. In the paper, a parametrization of the heat imbalance is carried out and the coefficient k f (z 0 ef /L ef ) is introduced as a measure of inhomogeneity. For this, data from the experiments FIFE, KUREX, TARTEX, SADE, etc., are also used. Empirical formulas are presented to refine the results of direct measurements and calculations of surface fluxes over natural (inhomogeneous) land surfaces from profile and standard (using bulk parametrizations) data. These formulas can also be used to determine surface fluxes over inhomogeneous underlying land surfaces in order to take into account so-called subgrid-scale effects in constructing prediction models.  相似文献   

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