The internal hydrographic structure of the Huanghai cold water mass (HCWM) in summer |
| |
| Authors: | Zhao Baoren Xiong Qingchen Zhang Fagao |
| |
| Institution: | 1. Institute of Oceanology, Academia Sinica, Qingdao, China
|
| |
| Abstract: | The deep and bottom water within the Huanghai Cold Water Mass (HCWM) in summer was, for a long time, considered as a homogeneous body of water. Various investigations in recent years showed this may not be true. After a detailed analysis of the most recently obtained CTD data and other historical hydrographic data at our disposal, some significant results have been obtained. - It is definitely shown that the Huanghai Warm Current (HWC) did not enter the HCWM in summer. However, there exist two types of second class water masses within the HCWM in summer. They are: (1) a water mass with low temperature and low salinity, which was formed in the preceding winter by a vertical mixing process locally, and (2) a water mass of relatively high temperature and high salinity, which is the remanent body of the HWC that entered the HCWM in preceding seasons, but was completely cut off from its source in summer. The spreading of these two water masses, the existence of a frontal zone at the boundary of the two water masses, and the cross-isopycnal mixing process have been identified.
- The most recent CTD data showed us that at most stations within the HCWM, there exists a central cold and less saline water under the main thermocline. In both temperature and salinity profiles, a temperature/salinity inversion and a secondary thermocline/halocline were clearly seen. The appearance of the central cold and less saline water suggests the existence of the intrusion of one water mass into another. The vertical dimension of the intrusion agrees satisfactorily with the calculated values according to Ruddick and Turner's formula based upon a double-diffusion hypothesis. These facts further prove the existence of different second class water masses (at least two) and also suggest the existence of a double-diffusion process in the HCWM.
- From the time difference of the occurrence of a salinity maximum/minimum at different latitudes, a “salinity wave” with a velocity of 3–4 m/s (and a period of about a year) was inferred. This agrees very well with the measured currents in this area.
|
| |
| Keywords: | |
| 本文献已被 CNKI SpringerLink 等数据库收录！ |
|
