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1.
An array of five buoys and three coastal stations is used to characterize the winds, stress, and curl of the wind stress over the shelf off Bodega Bay, California. The wind and wind stress are strong and persistent in the summer and weak in the winter. In the summer, wind and stress decrease strongly across the shelf, toward the coast. Combinations of buoys are used to compute the curl of the wind stress over different portions of the shelf. The mean summer 2001 curl of the wind stress over the array depends upon the area selected, varying between −1.32×10−6 and +7.80×10−6 Pa m−1. The winter 2002 wind-stress curl also depends on location, varying from −2.06×10−6 to +2.78×10−6 Pa m−1. Mean monthly curl of the wind stress is a maximum in the summer and a minimum near zero in the winter. In both the summer and the winter, the correlation between the wind-stress curl for different portions of the shelf varies between moderate negative, though insignificance, to high positive. A wind measurement at a single point can be poorly related to the measured curl of the wind stress at other locations over the shelf. The measurements show that the use of one wind measurement to characterize the curl of the wind stress over the shelf without further investigation of the local wind-stress curl structure is risky.  相似文献   

2.
The wind-stress field in the North Pacific Ocean during 1961–75 is computed from nearly five million ship reports. With a drag coefficient having a linear relation to wind speed, annual mean and monthly mean wind-stress fields are obtained, and their features are described.Compared with the stress fields obtained byHellerman (1967) andWyrtki andMeyers (1976), the eastward component of the stress in the present study is larger in magnitude and the northward one smaller in magnitude, especially in the trade wind region. Differences in the drag coefficient do not have a pronounced effect on the estimated stress field. Long-period inter-annual variations in the wind field are the most likely cause of the discrepancies between the present study and those of the above authors.The maximum of the wind-stress curl, estimated from the annual mean wind-stress fields, is as large as 1.0×10–8dyn cm–3 around 30°N, and is larger than that estimated byEvenson andVeronis (1975). The discrepancy is considered to be mainly due to differences in the computed stress field itself rather than due to differences in the grid size used in the stress computations.The Sverdrup transports integrated from the eastern boundary on the basis of the present stress field have a maximum greater than 40×10–12cm3 s–1 (Sv.) near the western boundary around 30°N. This value is closer to the observed transport of the Kuroshio than that based on Hellerman's stress field.  相似文献   

3.
A five-element mooring array is used to study surface boundary-layer transport over the Northern California shelf from May to August 2001. In this region, upwelling favorable winds increase in strength offshore, leading to a strong positive wind stress curl. We examine the cross-shelf variation in surface Ekman transport calculated from the wind stress and the actual surface boundary-layer transport estimated from oceanic observations. The two quantities are highly correlated with a regression slope near one. Both the Ekman transport and surface boundary layer transport imply curl-driven upwelling rates of about 3×10−4 m s−1 between the 40 and 90 m isobaths (1.5 and 11.0 km from the coast, respectively) and curl-driven upwelling rates about 1.5×10−4m s−1 between the 90 and 130 m isobaths (11.0 and 28.4 km from the coast, respectively). Thus curl-driven upwelling extends to at least 25 km from the coast. In contrast, upwelling driven by the adjustment to the coastal boundary condition occurs primarily inshore of the 40-m isobath. The upwelling rates implied by the differentiating the 40-m transport observations with the coastal boundary condition are up to 8×10−4 m s−1. The estimated upwelling rates and the temperature–nitrate relationship imply curl-driven vertical nitrate flux divergences are about half of those driven by coastal boundary upwelling.  相似文献   

4.
Boundary layer observations were made over the Gulf of Mexico over a 3-year period in order to develop and test methods for estimating surface fluxes and boundary layer wind fields. In addition to routinely available buoy and CMAN surface data, six 915 MHz radar wind profilers (RWPs) and RASS profilers were mounted on oil platforms and on the shore. Estimates of surface momentum, sensible heat, and latent heat fluxes have been made from the surface observations using the COARE software. Simulations by the National Weather Service's Eta meteorological model are compared with the observations of surface fluxes and wind profiles. The boundary layer is found to be unstable over 90% of the time, and latent heat fluxes are about five to ten times larger than sensible heat fluxes, as usually found over tropical oceans. Eta model simulations of surface fluxes are within about ±50% of COARE estimates of the fluxes based on surface observations. Most of the time, COARE-derived fluxes at 11 sites are within a factor of two of each other at any given hour. In multi-day case studies, COARE calculations are found to agree with Eta model simulations of these fluxes and parameters within a factor of two most of the time. Eta model simulations of wind speeds in the boundary layer tend to exceed the RWP observations by 1–2 m s−1 near shore and by 2–6 m s−1 at distances of 100–200 km offshore.  相似文献   

5.
Gridded data of global surface wind/wind-stress vectors, called J-OFURO v2, were obtained from satellite scatterometer (QuikSCAT/SeaWinds) data for the decade from August 1999 to July 2009. The data were validated by comparing with (1) in situ measurements from moored buoy observations, (2) a data product from the same scatterometer using a different gridding procedure (IFREMER), and (3) data products based on numerical models (NCEP-1 and NCEP-2). The results on averaging all buoy data revealed lower mean differences, lower root-mean-square (RMS) differences, and higher correlations for the wind/wind-stress components for the J-OFURO v2 product than the other data products. The statistical values calculated for each buoy station showed tendencies of decreasing reliability with increasing latitude in the mid-latitude region, while the reliabilities in the equatorial areas were low. We performed intercomparisons between the J-OFURO v2 data and the other data sets to clarify discrepancies among different wind products in open ocean regions with few moored buoys. We determined that the meridional wind components from the NCEP products exhibited poleward deviations compared to data from the J-OFURO v2 product. Relatively high mean differences, high RMS differences, and low correlations were found in the equatorial ocean for the NCEP products. Striped features were spatially correlated with buoy locations in the equatorial Pacific, which suggested that the reliability of the NCEP products was governed by buoy locations in this region.  相似文献   

6.
We analyze the time-longitude structure of composite cases from model-assimilated ocean data in the period 1958–1998, following on from earlier work by Huang and Kinter (J. Geophys. Res. 107(C11) (2002) 3199) that studied east–west thermocline variability in the Indian Ocean. Our analysis focuses on the Rossby wave signal along the thermocline ridge in the tropical SW Indian Ocean (10°S, 60–80°E), where wind stress curl is important. Anomalous winds in the equatorial east Indian Ocean force successive Rossby waves westward at speeds of 0.1 m s−1±30%. With a wavelength of 7000 km, the period of oscillation is in the range 1.9–5.2 years. The Indian Ocean Rossby wave is partially resonant with the global influence of the El Nino–Southern Oscillation, except during quasi-biennial rhythm. The presence of the Rossby wave offers potential predictability for east–west atmospheric circulation systems and climate that affect resources in countries surrounding the Indian Ocean.  相似文献   

7.
利用观测资料和理论模型,研究了孟加拉湾海表面高度的季节循环.结果表明,局地风应力旋度驱动的斜压Rossby波是孟加拉湾海表高度季节循环的主要控制因子,而孟加拉湾海底地形分布也影响了海表面高度的季节循环.受风应力旋度驱动的斜压Rossby波在短时间内就可以穿越孟加拉湾海盆,使得海洋温跃层在短时间内完成了对Rossby波的响应,保证了上层海洋满足准静止的Sverdrup平衡.在夏季(冬季)西南(东北)季风驱动下,上层海洋分别在孟加拉湾北部和南部形成气旋(反气旋)式和反气旋(气旋)式环流.  相似文献   

8.
The primary purpose of this paper is to describe the seasonal variation of the various currents which comprise the California Current System—the California Current, the California Undercurrent, the Davidson Current and the Southern California Countercurrent—and to investigate qualitatively the dynamical relationships among these currents. Although the majority of information was derived from existing literature, previously unpublished data are introduced to provide direct evidence for the existence of a jet-like Undercurrent over the continental slope off Washington, to illustrate ‘event’-scale fluctuations in the Undercurrent and to investigate the existence of the Undercurrent during the winter season.The existing literature is thoroughly reviewed and synthesized. In addition, and more important, geostrophic velocities are computed along several sections from the Columbia River to Cape San Lazaro from dynamic heights given by (1966), and (1964), and and (1976). From these data and from long-term monthly wind stress data and vertical component of wind stress curl data (denoted curl τ) given by (1977), interesting new conclusions are made. 1. The flow that has been denoted the California Current generally has both an offshore and a nearshore maximum in its alongshore coponent. 2. The seasonal variation of the nearshore region of strong flow appears to be related to the seasonal variation of the alongshore component of wind stress at the coast, τyN, at all latitudes. Curl τ near the coast may also contribute to the seasonal signal, accounting for the lead of maximum current over maximum wind stress from about 40°N northward. Large-scale flow separation and fall countercurrents that of headlands may account for the sudden occurrence of late summer and fall countercurrents that appear as large anomalies from the wind-driven coastal flow south of 40°N. 3. From Cape Mendocino southward a northward mean is imposed on the nearshore current distribution. The mean is largest where curl τ is locally strongest, in particular, off and south of San Francisco and in the California Bight. It may be responsible for the portion of the Davidson Current that occurs off California, for the San Francisco Eddy and for the Southern California Eddy or Countercurrent. When southward wind stress weakens in these regions, the northward mean dominates the flow. Flow separation in the vicinity of headlands may also be responsible for these northward flows. There is some evidence that during periods of northward flow a mean monthly τyN-driven southward current occurs inshore of the mean northward flow. At all latitudes, wind-driven ‘event’-scale fluctuations are expected to be superimposed on the seasonal nearshore flow. 4. The spatial distribution and seasonal variation oftthe offshore region of southward flow appear to be related to the spatial distribution and seasonal variation of curl τ. The seasonal variation of curl τ in these areas, curl τl, is roughly in phase with the seasonal variation of τy near the coast and roughly 180° out of phase with the seasonal variation of curl τ near the coast. Southward flow lags negative curl τ by from two to four months. The offshore region of southward flow is strongest during the summer and early fall. The mean annual location of the maximum flow is at about 250–350 km from shore off Washington and Oregon, and at 430 km off Cape Mendocino, 270 km off Point Conception and 240 km off northern Baja. The offshore branch of the flow bends shoreward near 30°N, which is consistent with the shoreward extension of the region of negative curl τ, so that by Cape San Lazaro (25°N), a single region of strong flow is observed within 200 km of the coast. 5. A third region of strong southward flow occurs at distances exceeding 500 km from the coast. The spatial distribution of this flow appears to be related to the spatial distribution of curl τ. 6. The mean northward flow known as the Davidson Current consists of two regions in which the forcing may be dynamically different—seaward of the continental slope off Washington and Oregon and between Cape Mendocino and Point Conception, the mean monthly northward currents appear to be related to the occurrence of positive curl τ; along the coast of Oregon and Washington the northward currents are not related to the occurrence of positive curl τ but are consistent with forcing by the mean monthly northward wind stress at the coast. 7. A region of southward flow that is continuous with the California Current to the south is generally maintained off Oregon and parts of Washington during the winter. This southward flow appears to separate the northward-flowing Davidson and Alaskan Currents in some time-dependent region south of Vancouver Island. The banded current structure is consistent with the distribution of curl τ, if southward flow is related to negative curl τ. 8. The seasonal progression of the California Undercurrent may be related both to the seasonal variation of the offshore region of strong flow (hence to curl τl) and to the alongshore component of wind stress at the coast. South of Cape Mendocino a northward mean also seems to be superimposed on the flow. This mean may be related to the occurrence of strong positive curl τ near the coast. Velocities at Undercurrent depths have two maxima, one in late summer and one in winter. The slope Undercurrent is indistinguishable, except by location, from the undercurrent that is observed on the Oregon-Washington continental shelf.  相似文献   

9.
The wind speeds and significant wave heights observed by the TOPEX altimeter during the first 30 repeat cycles (for about 10 months) are validated by comparing with the data obtained at Japanese Ocean Data Buoy stations. The values of Kuband 0 observed by the altimeter show good agreement with those estimated from the buoy wind speed using the modified Chelton-Wentz algorithm. The wind speeds derived from the Ku-band 0 using the algorithm agree well with the buoy data with an rms difference of 1.99 ms–1. The significant wave heights observed by the altimeter have a systematic bias of 0.3 m.  相似文献   

10.
To develop a simple method to predict the significant wave height, we analyze 18 years of hourly observations from 12 different buoys that are off the northeast coast of the United States. Water depths ranged from 19 to 4427 m for these moored buoys. We find that, on average, all of these buoys exhibit a region of constant wave height for 10-m wind speeds between 0 and 4 m s−1. That wave height does, however, depend on water depth. For wind speeds above 4 m s–1, the wave height increases as the square of the wind speed; but the multiplicative factor is again a function of water depth. We synthesize these results in a prediction scheme that yields the significant wave height from simple functions of water depth and 10-m wind speed for wind speeds up to 25 m s–1.  相似文献   

11.
A small, inexpensive, and easily deployable meteorological buoy is described. Buoy motion is greatly reduced by appropriate ballast techniques; vector averaging further removes buoy motion effects from wind data. Data is transmitted to the GOES satellite and is retrieved by telephone. Measurements are vector-averaged wind components, wind speed, wind direction, water temperature, air temperature, and compass direction. Data from two field trials are discussed. Speed comparisons averaged 0.2 m sec−1 with a standard deviation of 0.6 m sec−1. Direction comparisons were different due to local topography, but they indicate a probable accuracy of ±5°.  相似文献   

12.
In order to validate wind vectors derived from the NASA Scatterometer (NSCAT), two NSCAT wind products of different spatial resolutions are compared with observations by buoys and research vessels in the seas around Japan. In general, the NSCAT winds agree well with the wind data from the buoys and vessels. It is shown that the root-mean-square (rms) difference between NSCAT-derived wind speeds and the buoy observations is 1.7 ms–1, which satisfies the mission requirement of accuracy, 2 ms–1. However, the rms difference of wind directions is slightly larger than the mission requirement, 20°. This result does not agree with those of previous studies on validation of the NSCAT-derived wind vectors using buoy observations, and is considered to be due to differences in the buoy observation systems. It is also shown that there are no significant systematic trends of the NSCAT wind speed and direction depending on the wind speed and incidence angle. Comparison with ship winds shows that the NSCAT wind speeds are lower than those observed by the research vessels by about 0.7 ms–1 and this bias is twice as large for data observed by moving ships than by stationary ships. This result suggests that the ship winds may be influenced by errors caused by ship's motion, such as pitching and rolling.  相似文献   

13.
Marine surface winds observed by two microwave sensors, SeaWinds and Advanced Microwave Scanning Radiometer (AMSR), on the Advanced Earth Observing Satellite-II (ADEOS-II) are evaluated by comparison with off-shore moored buoy observations. The wind speed and direction observed by SeaWinds are in good agreement with buoy data with root-mean-squared (rms) differences of approximately 1 m s−1 and 20°, respectively. No systematic biases depending on wind speed or cross-track wind vector cell location are discernible. The effects of oceanographic and atmospheric environments on the scatterometry are negligible. Though the wind speed observed by AMSR also showed agreement with buoy observations with rms difference of 1.27 m s−1, the AMSR wind speed is systematically lower than the buoy data for wind speeds lower than 5 m s−1. The AMSR wind seems to have a discontinuous trend relative to the buoy data at wind speeds of 5–6 m s−1. Similar results have been obtained in an intercomparison of wind speeds globally observed by SeaWinds and AMSR on the same orbits. A global wind speed histogram of the AMSR wind shows skewed features in comparison with those of SeaWinds and European Centre for Medium-range Weather Forecasts (ECMWF) analyses.  相似文献   

14.
Macrozoobenthic biomass in the Bay of Seine (eastern English Channel)   总被引：1，自引：0，他引：1  
The benthic biomass values of various trophic groups were studied for the first time at the scale of the entire Bay of Seine (50 × 100 km) in the eastern English Channel. Sampling was carried out before and after the winter of 1999. In both cruises the suspension feeders dominated (66% of the 12 gAFDW m− 2 in 1998 and 56% of the 10 gAFDW m− 2 in 1999).The common European ophiuroid Ophiothrix fragilis was the most important contributor to total biomass. The repartition of its patches (sometimes > 20 gAFDW m− 2) cannot be explained by the environmental parameters recorded (viz., granulometry, organic matter and pigment content).  相似文献   

15.
Mesoscale eddies and tropical instability waves in the eastern tropical Pacific, first revealed by satellite infrared imagery, play an important role in the dynamics and biology of the region, and in the transfer of mass, energy, heat, and biological constituents from the shelf to the deep ocean and across the equatorial currents.From boreal late autumn to early spring, four to 18 cyclonic or anticyclonic eddies are formed off the coastal region between southern Mexico and Panama. The anticyclonic gyres, which tend to be larger and last longer than the cyclonic ones, are the best studied: they typically are 180–500 km in diameter, depress the pycnocline from 60 to 145 m at the eddy center, have swirl speeds in excess of 1 m s−1, migrate west at velocities ranging from 11 to 19 cm s−1 (with a slight southward component), and maintain a height signature of up to 30 cm. The primary generating agents for these eddies are the strong, intermittent wind jets that blow across the isthmus of Tehuantepec in Mexico, the lake district in Nicaragua and Costa Rica, and the Panama canal. Other proposed eddy-generating mechanisms are the conservation of vorticity as the North Equatorial Counter Current (NECC) turns north on reaching America, and the instability of coastally trapped waves/currents.Tropical Instability Waves (TIWs) are perturbations in the SST fronts on either side of the equatorial cold tongue. They produce SST variations on the order of 1–2 °C, have periods of 20–40 days, wavelengths of 1000–2000 km, phase speeds of around 0.5 m s−1 and propagate westward both north and south of the Equator. The Tropical Instability Vortices (TIVs) are a train of westward-propagating anticyclonic eddies associated with the TIWs. They exhibit eddy currents exceeding 1.3 m s−1, a westward phase propagation speed between 30 and 40 km d−1, a signature above the pycnocline, and eastward energy propagation. Like the TIWs, they result from the latitudinal barotropically unstable shear between the South Equatorial Current (SEC) and the NECC with a potential secondary source of energy from baroclinic instability of the vertical shear with the Equatorial Undercurrent (EUC).This review of mesoscale processes is part of a comprehensive review of the oceanography of the eastern tropical Pacific Ocean.  相似文献   

16.
In July 2002, a combination of underway mapping and discrete profiles revealed significant along-shore variability in the concentrations of manganese and iron in the vicinity of Monterey Bay, California. Both metals had lower concentrations in surface waters south of Monterey Bay, where the shelf is about 2.5 km wide, than north of Monterey Bay, where the shelf is about 10 km wide. During non-upwelling conditions over the northern broad shelf, dissolvable iron concentrations measured underway in surface waters reached 3.5 nmol L−1 and dissolved manganese reached 25 nmol L−1. In contrast, during non-upwelling conditions over the southern narrow shelf, dissolvable iron concentrations in surface waters were less than 1 nmol L−1 and dissolved manganese concentrations were less than 5 nmol L−1. A pair of vertical profiles at 1000 m water depth collected during an upwelling event showed dissolved manganese concentrations of 10 decreasing to 2 nmol L−1, and dissolvable iron concentrations of 12–20 nmol L−1 in the upper 100 m in the north, compared to 3.5–2 nmol L−1 Mn and 0.6 nmol L−1 Fe in the upper 100 m in the south, suggesting the effect of shelf width influences the chemistry of waters beyond the shelf.These observations are consistent with current understanding of the mechanism of iron supply to coastal upwelling systems: Iron from shelf sediments, predominantly associated with particles greater than 20 μm, is brought to the surface during upwelling conditions. We hypothesize that manganese oxides are brought to the surface with upwelling and are then reduced to dissolved manganese, perhaps by photoreduction, following a lag after upwelling.Greater phytoplankton biomass, primary productivity, and nutrient drawdown were observed over the broad shelf, consistent with the greater supply of iron. Incubation experiments conducted 20 km offshore in both regions, during a period of wind relaxation, confirm the potential of these sites to become limited by iron. There was no additional growth response when copper, manganese or cobalt was added in addition to iron. The growth response of surface water incubated with bottom sediment (4 nmol L−1 dissolvable Fe) was slightly greater than in control incubations, but less than in the presence of 4 nmol L−1 dissolved iron. This may indicate that dissolvable iron is not as bioavailable as dissolved iron, although the influence of additional inhibitory elements in the sediment cannot be ruled out.  相似文献   

17.
Horizontal wind fields over Funka Bay during cold air outbreaks were simulated using a 3-D meso-scale atmospheric model. The simulated wind fields over the bay have a positive curl in the north and a negative curl in the south. These wind fields were used to simulate the current in Funka Bay using a barotropic ocean model. The simulated current pattern was composed of two vortices—one with anti-clockwise vorticity in the north and the other with clockwise vorticity in the south—and was in the opposite direction to that simulated by the uniform wind fields. This is because the wind stress curl effect on the vorticity production in Funka Bay opposes and overwhelms the bathymetry torque effect during cold air outbreaks. These results show that the non-uniformity of the wind fields caused by the land topography around a shallow lake or bay cannot be neglected in simulating its currents.  相似文献   

18.
As part of a study of estuarine selenium cycling, we measured the concentration, chemical form (speciation), and distribution of particulate selenium under various river flow conditions in the North San Francisco Bay (from the Golden Gate to the Sacramento and San Joaquin Rivers). We also conducted laboratory studies on the accumulation of selenium by phytoplankton, the critical first step in the transformation of dissolved to particulate selenium. Total particulate selenium concentration in the North SF Bay was relatively constant between high and low flow periods, ranging spatially from 0.05 to 0.35 nmol l−1 and comprising between 5 and 12% of the total water column selenium inventory. Mean concentrations were generally highest in the Carquinez Strait–Suisun Bay region (salinity 0–17) and lowest in Central Bay. However, selenium content of suspended particles varied with river flow, with higher content during low flow (9.76 ± 4.17 nmol g−1; mean ± sd; n = 67) compared to high flow (7.10 ± 4.24 nmol g−1; n = 39). Speciation analyses showed that most particulate selenium is organic selenide (45 ± 27%), with a smaller proportion (typically <30%) of adsorbed selenite + selenate and a varying proportion (35 ± 28%) of elemental selenium. Based on the amount of elemental selenium in the seston (total suspended material), we calculate that resuspension of estuarine sediments could contribute 29–100% of particulate selenium in the water column. While selenium content of SF Bay seston (>0.4 μm) is relatively unenriched compared to phytoplankton (13.6–155 nmol g−1 dry weight) on a mass basis, when normalized to carbon or nitrogen, seston contains a similar selenium concentration to SF Bay sediments or phytoplankton cultures. SF Bay seston is thus comprised of selenium-rich phytoplankton and phyto-detritus, but also inorganic clay mineral particles that effectively “dilute” total particulate selenium. Selenium concentrations in algal cultures (11 species) exposed to 90 nmol l−1 selenite show relatively large differences in selenium accumulation, with the diatoms, chlorophytes and cryptophytes generally having lower selenium cell content (3.8 ± 2.7 × 10−9 nmol selenium cell−1) compared to the dinoflagellates (193 ± 73 × 10−9 nmol selenium cell−1). Because phytoplankton are such a rich (but variable) source of selenium, their dynamics could have a profound effect on the particulate selenium inventory in the North SF Bay.  相似文献   

19.
钱思佳  于方杰  陈戈 《海洋科学》2021,45(11):10-19
本文使用基于热成风速度的涡旋识别拓展方法,通过海表面温度数据对黑潮延伸体区域50~100 km涡旋进行研究,发现50~100 km涡旋主要分布在黑潮延伸体流轴两侧,气旋涡和反气旋涡的寿命、半径分布具有一致性。气旋涡多出现在35°N以北,反气旋涡在35°N以南比较集中,与尺度较小的中尺度涡旋分布特征较为相似。冬夏两季涡旋地理分布存在一定差异,主要与不同季节该区域海表温度梯度及风应力旋度的变化有关。35°N以南50~100 km涡旋数量的季节性变化与风速大小的季节性变化存在明显的正相关性。35°N以南50~100 km涡旋三倍半径内风速异常和风应力旋度归一化表明,气旋涡对应风速负异常而反气旋涡对应风速正异常,反气旋涡的产生依赖于风应力负旋度,气旋涡的生成与风应力正旋度有关。  相似文献   

20.
本文使用基于热成风速度的涡旋识别拓展方法,通过海表面温度数据对黑潮延伸体区域50-100公里涡旋进行研究,发现50-100公里涡旋主要分布在黑潮延伸体流轴两侧,气旋涡和反气旋涡的寿命、半径分布具有一致性。气旋涡多出现在35°N以北,反气旋涡在35°N以南比较集中,与尺度较小的中尺度涡旋分布特征较为相似。冬夏两季涡旋地理分布存在一定差异,主要与不同季节该区域海表温度梯度及风应力旋度的变化有关。35°N以南50-100公里涡旋数量的季节性变化与风速大小的季节性变化存在明显的正相关性。35°N以南50-100公里涡旋三倍半径内风速异常和风应力旋度归一化表明,气旋涡对应风速负异常而反气旋涡对应风速正异常,反气旋涡的产生依赖于风应力负旋度,气旋涡的生成与风应力正旋度有关。  相似文献   

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