排序方式: 共有40条查询结果,搜索用时 421 毫秒
11.
12.
13.
14.
15.
16.
17.
David L. Pawson 《新西兰海洋与淡水研究杂志》2013,47(3):227-230
A new species in the dendrochirotid holothurian genus Ocnus sensu lato is described from approximately 600 m depth in Taiaroa Canyon, off Otago, New Zealand. Ocnus sacculus new species has single rows of tubefeet only in the 3 ventral radii. Body‐wall ossicles consist of cups, knobbed 4‐holed buttons, and multi‐layered plates averaging 0.7 mm in diameter. Three brood pouches lie anteriorly on the inner surface of the body wall in 3 dorsal interradii; the mid‐dorsal pouch is largest. The pouches apparently have no permanent contact with the exterior; presumably birth takes place by rupture of the body wall. 相似文献
18.
19.
An intercomparison of the thermal structure and the annual cycle in the tropical lower stratosphere of two reanalysis datasets
is presented. These are from the National Centers for Environmental Prediction (NCEP)/National Center for Atmospheric Research
(NCAR) and the European Centre for Medium Range Weather Forecasts (ECMWF Re-Analysis: ERA). Generally, the ERA data are coldest
and in better agreement with radiosonde observations; this is particularly apparent at 100 hPa where there is also a strong
geographic bias, the maximum differences (more than 4 K) occurring over the southern Pacific and the Indian Ocean, with much
smaller (sometimes reversed) differences over land. The NCEP temperatures are biased towards satellite-derived values, while
the ERA data resolve the low tropopause temperatures much better. The lower ERA temperatures have important implications for
the cross-tropopause exchange of water vapor. The meridional-height structure of the annual cycles agree quite well, but the
amplitude in the ERA data is about 50% stronger than in NCEP at 70 hPa (in better agreement with previous studies) and weaker
at lower pressures. As in previous studies, an anticorrelation is found between the tropical and extratropical temperatures
of the reanalyses. The mean meridional flow at the equator is northward all year at all stratospheric levels in the NCEP data,
implying a mass transport from the Southern to the Northern Hemisphere; in the ERA data the expected annual cycle (flow from
summer to winter) is reproduced with very small annual mean exchange.
Received: 17 June 1997/Accepted: 17 December 1997 相似文献