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1.
Ocean wave characteristics around New Zealand 总被引：1，自引：1，他引：0
Nearly 17 years wave records from deep water and shore‐based stations are used to describe the ocean wave characteristics around New Zealand. The wave environment is dominated by west and southwest swell and storm waves generated in the temperate latitude belt of westerly winds. As a result, the west and south coasts are exposed, high energy shores, the east coast is a high energy lee shore, and the northern coast from North Cape to East Cape is a low energy lee shore sheltered from these winds and waves. South of New Zealand, wave energies are extremely high; the prevailing deep water wave is 3.5–4.5 m high and has a 10–12 s period, with a slight increase in wave heights in winter. The west coast wave environment is mixed, and consists of locally generated westerly and southerly storm waves, and swell waves generated to the south. The prevailing wave is t.0–3.0 m and 6–8 s period. There are no strong seasonal rhythms, only shorter period cycles of wave height (5 day) associated with similar quasi‐rhythmic cycles in the weather. The east coast also has a mixed wave climate with southerly swells, originating in the westerlies south of New Zealand, and locally generated southerly and northerly storm waves. The prevailing wave is 0.5–2.0 m and 7–11 s period. A short period rhythmic cycle, similar to that on the west coast, is superimposed on a weak seasonal cycle. The seasonal, cycle results from an increase in the frequency of local northerly waves in summer. The prevailing wave on the north coast is a northeasterly, 0.5–1.5 m high and 5–7 s period. Subtropical disturbances and southward‐moving depressions generate a mixed wave environment and a possible seasonally reflecting a winter increase in. storminess. 相似文献
2.
Fifteen proteins encoded by 23 gene loci were electrophoretically surveyed in two samples of snapper Chrysophrys auratus (Forster) from Wellington Harbour and the Hauraki Gulf. Between 17% and 26% of the loci examined were found to be polymorphic and the proportion of heterozygous loci per individual was 7.9% to 8.4%. Using Rogers’ genetic distance coefficient an overall similarity of 0.98 was calculated between the two samples. Three polymorphic loci Est‐4, Gpi‐1, and Idh were examined in an additional 10 samples from around New Zealand. Two genetically distinct stocks were apparent: one along the west coast, the other along the east coast of the North Island. There was an indication of stock mixing at Ninety Mile Beach and in the Bay of Plenty and East Cape. The distribution of alleles at the Est‐4 locus revealed a third stock in Hawke Bay that is genetically more similar to the west coast than the east coast stock. Hydrological conditions in Hawke Bay are more similar to those of the west coast than to those of the north east coast of the North Island. Thus it is possible that Est‐4 alleles are selectively maintained in response to an environmental factor. 相似文献
3.
Masaki Kawabe 《Journal of Oceanography》1980,36(2):97-104
Sea level variations from 1974 through 1976 at 9 stations on the south coast of Japan (from west to east, Aburatsu, Tosa-shimizu, Muroto-misaki, Kushimoto, Uragami, Owase, Toba, Maisaka and Omaezaki) were analysed in relation to the large meander in the Kuroshio. From May to July in 1975, a small maximum in sea level variation was observed at every station west of Cape Shionomisaki from Aburatsu to Kushimoto. It propagated eastward along with the eastward propagation of a small meander in the Kuroshio until it reached Kushimoto, when the sea levels at Uragami and Owase started to rise sharply. This remarkable rise appeared at all stations in August when a large meander in the Kuroshio was established. The mean sea level at the stations east of Cape Shionomisaki from Uragami to Omaezaki rose by about 10 cm. The difference in sea level variations between the regions east and west of Cape Shionomisaki, which had been present before the rise, disappeared. A similar characteristic of sea level variation was also found in the generation stage of the large meander in 1959. The sea level variations along the south coast of Japan indicate that, prior to the generation of the large meander, the small meander in the Kuroshio was generated southeast of Kyushu and propagated eastward and that, just when this meander reached off Cape Shionomisaki, a large scale oceanic event covering over the whole region of the south coast of Japan occurred. This large scale event seems to be one of the necessary conditions for the generation of the large meander in the Kuroshio off Enshû-nada. 相似文献
4.
The genetic structure of populations is often shaped by the reproductive system and larval properties of the species. The waratah anemone (Actinia tenebrosa) reproduces through both asexual clones, which have very short-distance dispersal, and sexual larvae, which are believed to disperse much greater distances. The impact of this mixed strategy on the New Zealand population structure of Actinia tenebrosa was investigated using microsatellite markers. The analysis incorporated 24 sampling locations from around New Zealand and one Australian location, using four microsatellite markers, n = 420. We observed low connectivity and high genetic differentiation between all locations sampled, with a distinct pattern of isolation by distance. The most distinct grouping of locations sampled was the north-east of the North Island from Cape Reinga to East Cape, which was identified by SAMOVA and STRUCTURE analyses as being moderately diverged from the remainder of the country. A tentative correlation was observed between genetic clustering and biogeographic regionalisation, where the distribution of a number of genetic clusters matched previously defined biogeographic regions. Within each location sampled, large numbers of clones were present and a latitudinal cline was observed in the relative contribution of asexually and sexually generated recruits, with an increase in asexual recruits on the South Island's east coast. 相似文献
5.
E. J. Barnes 《新西兰海洋与淡水研究杂志》2013,47(3):405-411
Sea‐surface temperature data from satellite imagery is used to improve the understanding of the ocean‐current circulation of an area to the south‐east of Cook Strait, New Zealand. A dominant feature of the satellite imagery is an eddy, apparently locked in position, which has a considerable influence on the interaction of the East Cape Current and the Southland Current which meet in this region. 相似文献
6.
Hydrological conditions and circulation off the west coast of the North Island,New Zealand 总被引：1，自引：1，他引：0
N.M. Ridgway 《新西兰海洋与淡水研究杂志》2013,47(2):155-167
Temperature and salinity surveys were carried out in the Tasman Sea in winter (August 1973) and summer (February‐March 1974). In both surveys the presence of the Westland Current was indicated by the distribution of surface water properties; in summer it was associated with a subsurface salinity maximum. The current extended further northwards in summer than in winter. In summer, an east‐going geostrophic flow at about latitude 35°S separated on approaching New Zealand; part of the flow passed north around the North Island and part moved slowly eastwards in the deeper off‐shore water to at least latitude 38°S. The West Auckland Current was apparent in the winter, but not in the summer. To the west of Cape Reinga, relatively low values of surface temperature and salinity are probably associated with upwelling between Cape Reinga and the Three Kings Islands. Upwelling was observed along the coast between Kaipara and Manukau Harbour. 相似文献
7.
Flow in the East Auckland Current (EAUC) system to the north‐east of North Cape, New Zealand is examined using data from two current meter mooring arrays, with supporting data from conductivity/temperature/depth (CTD) and satellite altimetry. Variable currents up to 45 cm s–1 were observed. The variability was partly attributable to changes in position and strength of the North Cape Eddy whose centre lies some 150 km offshore. The observed flows across the mooring line correlate well with those estimated from satellite altimetry. This gives confidence in the use of the satellite data to estimate the transport variability in the EAUC in the 1992–2001 period. No seasonal cycle was found in the volume transports but rather broadband variability at periods longer than 100 days. 相似文献
8.
Ocean temperature changes around New Zealand are estimated from satellite sea surface temperature (SST) products since 1981, two high resolution expendable bathythermograph transects (HRXBT) since 1986 and 1991, and Argo data since 2006. The datasets agree well where they overlap. Significant surface warming is found in subtropical waters. Greatest warming is east of Australia and in the central Pacific. All NZ coastal waters are warming, with strongest warming east of Wairarapa and weakest between East Cape and North Cape. Temperature changes are surface intensified, extending to ～200 m in the northeast and at least 850 m in the eastern Tasman. Significant interannual variability is coherent over a large area of ocean north of the Subtropical Front and modulates extreme events. NZ air temperatures are highly correlated at interannual timescales with SSTs over a broad region of ocean north of the Subtropical Front from the eastern Tasman to east of the dateline. 相似文献
9.
R. A. Heath 《新西兰海洋与淡水研究杂志》2013,47(1):178-199
The circulation and hydrology of Cook Strait are defined using both the geostrophic method and the hydrologiieal characteristics of the different water masses. Cool, low salinity water in a branch of the Southland Current, which extends along the east coast of the South Island into Cook Strait, mixes above the depth of the continental shelf with warmer, more saline Subtropical Water from both the D'UrVille Current and the East Cape Current. Subtropical Water derived from the East Cape Current occupies the Cook Strait Canyon; below 100 m this water meets the Subtropical Water of the southwest‐flowing D'Urville Current in a convergence situated in the Oook Strait Narrows. Mixed water derived from all three currents passes eastwards across Cook Strait and up the east coast of the North Island. 相似文献
10.
Neil J Holbrook Ian D GoodwinShayne McGregor Ernesto MolinaScott B Power 《Deep Sea Research Part II: Topical Studies in Oceanography》2011,58(5):547-558
The connection between East Australian Current (EAC) transport variability and Australia’s east coast sea level has received little treatment in the literature. This is due in part to the complex interacting physical processes operating in the coastal zone combined with the sparsity of observations available to improve our understanding of these possible connections. This study demonstrates a statistically significant (at the >90% level) relationship between interannual to decadal time scale variations in observed estimates of the EAC transport changes and east coast sea level measured at the high-quality, long record Fort Denison tide-gauge in Sydney Harbour, Australia (33°51′18″S, 151°13′32″E). We further demonstrate, using a linear reduced-gravity ocean model, that ENSO to decadal time-scale variations and the ocean-adjusted multi-decadal trend (approx. 1 cm/decade) in observed sea level at Fort Denison are strongly connected to modulations of EAC transports by incoming westward propagating oceanic Rossby waves. We show that EAC transport and Fort Denison sea level vary in a manner expected from both Tasman Sea generated Rossby waves, which account for the interannual and multi-annual variability, and remotely forced (from east of New Zealand) Rossby wave connections through the mid-latitudes, accounting for the ocean-adjusted multi-decadal trend observed at the New South Wales coast - with the regional-Tasman Sea forcing explaining the greatest overall proportion of EAC transport and sea-level variances. 相似文献
11.
G. D. James 《新西兰海洋与淡水研究杂志》2013,47(1):45-52
Catches of iack mackerel Trachurus declivis taken everv 2 months from the west coast of New Zealand show that this species attains lengths of approximately 11 cm and 24 cm at the completion of the first and second years of life respectively. Above these lengths, year classes overlap considerably. Juveniles were found from Westland to North Cape and were most abundant in surface waters. 相似文献
12.
J. H. R. Lesser 《新西兰海洋与淡水研究杂志》2013,47(4):357-370
The complete series of phyllosoma larval stages of spiny lobster lasus edwardsii are described. Eleven stages are recognised from specimens captured in plankton samples collected along a transect extending 185 km east of Castlepoint, North Island, New Zealand between July 1969 and December 1971. A table of distinguishing characteristics and a key for identification of stages are presented. First stage larvae occur between August and October and last stage larvae about 15 months later. Mortality through the phyllosoma stages is estimated to be 98%. Early stage larvae occur mainly inshore in Southland Current water in the upper 5 m, and later stage larvae occur more frequently offshore in East Cape Current water at 40–60 m depth. 相似文献
13.
Distribution of Delphinidae (Cetacea) in relation to sea surface temperatures off Eastern and Southern New Zealand 总被引：1，自引：1，他引：0
D. E. Gaskin 《新西兰海洋与淡水研究杂志》2013,47(3):527-534
Records of four species of Delphinidae, Delphinus delphis, Lissodelphis peroni, Lagenorhynchus obscurus, and Lagenorhynchus cruciger in waters to the east and south‐east of New Zealand are discussed in relation to surface temperatures. In this region D. delphis appears to be largely confined north of the Subtropical Convergence and a minimum surface temperature of about 14°c, and near New Zealand from Hawke Bay southward in the warm water of the East Cape Current; L. peroni to the Subtropical Convergence and the subantarctic water to the south of it, between surface temperatures of 9°c and 16°c; L. obscurus to the immediate vicinity of the Subtropical Convergence and surface temperatures in summer of about 14° to 15°c, and L. cruciger across the Antarctic Convergence region, in a surface temperature range of 2° to 9°c. 相似文献
14.
15.
B. R. Stanton 《新西兰海洋与淡水研究杂志》2013,47(1-2):85-110
16.
Hydroclathrus clathratus (C. Agardh) Howe (Phacophyta: Punctariales) is recorded from two harbours on the Northland east coast, North Island, New Zealand. The possibility of its being a recently introduced species is discussed. 相似文献
17.
Surface distribution of albacore tuna,Thunnus alalunga Bonnaterre,in relation to the Subtropical Convergence Zone east of New Zealand 总被引：1，自引：1，他引：0
P. E. Roberts 《新西兰海洋与淡水研究杂志》2013,47(4):373-380
Trolling surveys showed that albacore tuna are about equally abundant in subtropical and Subtropical Convergence Zone surface waters off the south‐east coast of New Zealand. Few albacore were located in Subantarctic Surface Water, indicating that the Subtropical Convergence Zone is the southern limit for albacore in this area. 相似文献
18.
Peter L. Horn 《新西兰海洋与淡水研究杂志》2013,47(3):623-631
In late 1987, bluenose (Hyperoglyphe antarctica) were tagged with streamers attached to fish hooks, at six commercial fishing grounds between Gisborne and Cape Palliser, New Zealand. The tagged hooks were fished on commercial trot lines, but were attached with traces of 5.5 kg breaking strain nylon that broke when the fish took the hook and struggled to escape. Based on catches from full strength control lines fished simultaneously with the detachable gear, 1971 bluenose were tagged. In the subsequent 8.5 years, 44 tagged bluenose (where both the sites of tagging and recapture where known) were recaptured. All but seven of these returns occurred in the first year after tagging, indicating that the rate of long‐term tag retention was not good. Bluenose appeared to be relatively sedentary in the short term, but were capable of quite rapid and extensive movement. Four tagged fish had travelled distances in excess of 450 km, with movements to both the north and south of the tagging area. These data indicate that bluenose off the eastern coast of New Zealand between North Cape and Kaikoura probably comprise a single biological stock. 相似文献
19.
The input of river-borne sediments to the New Zealand continental shelf has been calculated for all the major rivers and basins in New Zealand. South Island yields 284 ± 40 × 106 tonnes per year of sediment from a land area of 152 977 km2 and North Island yields 105 ± 9·4 × 106 tonnes per year from a land area of 114 621 km2. Particularly high discharges are noted off the west coast of South Island and east coast of North Island and result in higher offshore sedimentation there. The data are compatible with measured sedimentation rates on the New Zealand continental shelf. The specific sediment yield from South Island is amongst the highest previously recorded. 相似文献
20.
C. A. J. Duffy 《新西兰海洋与淡水研究杂志》2013,47(3):565-570
Data from 36 whale shark (Rhincodon typus Smith, 1828) sightings off north‐east North Island, New Zealand are summarised. Sightings were concentrated over the outer shelf and shelf break in areas influenced by the East Auckland Current at sea surface temperatures (SST) of 21–24°C. Sightings occurred from late spring to early autumn (November‐April) but were most frequent in midsummer (February) when upwelling along the north‐east shelf is weakest. The data indicate whale sharks occur off north‐east New Zealand most summers, including those when SST is colder than usual. A cluster of sightings and three observations of whale sharks feeding on schools of anchovy (Engraulis australis) near Whale Island, Bay of Plenty, suggest whale sharks may aggregate seasonally in this area. Estimated total lengths (TL) of 26 whale sharks ranged from 3.5 to 15 m, with 73% between 6 and 9 m TL. 相似文献