海南岛地形对局地海风环流结构影响的数值模拟

发布时间：2017-12-28 22:17

本文关键词：海南岛地形对局地海风环流结构影响的数值模拟　出处：《海洋学报》2017年03期 　论文类型：期刊论文

【摘要】：本文利用WRF模式对2014年5月25日发生在海南的一次海风过程进行了数值模拟,通过地形敏感性试验,探讨了海南岛地形对局地海风环流结构的影响。结果表明:控制试验(CNTL)海风于15时左右达到强盛。无地形试验(FLAT)中,水平方向上,海风持续时间缩短,南、北、西向海风向内陆传播距离变短1~5km,海风强度减弱1m/s左右,海风动能及辐合强度在沿海地区及西南山区存在大值衰减区;垂直方向上,海风碰撞位置向西、北方向移动,高空回流高度降低,海风厚度减小,垂直环流强度减弱2~6m2/s2,海风锋附近的垂直速度减小10cm/s以上。谷风对海风同相叠加作用的消失也使得海风强度减弱。其主要影响机制为:在动力方面,由山脉屏障作用引起的海风强迫抬升、绕流等增强作用消失;在热力方面,地表吸收净辐射减少,导致其向大气中释放的感热、潜热通量等各项均减少约9%,这种改变造成了海陆之间温度、气压差的减小,最终造成了海风的减弱。此外,通过两组削山试验,发现海拔高度降低区辐合范围、强度及动能均减小,同时海风垂直环流结构也相应发生改变,其中移去黎母山脉(RMLM)对海风环流结构的影响大于移去五指山脉(RMWZ)。
[Abstract]:In this paper, a WRF model is applied to simulate the sea breeze process in Hainan in May 25, 2014. The influence of Hainan Island topography on the local sea breeze circulation structure is discussed through the terrain sensitivity test. The results show that the control test (CNTL) of the sea breeze is strong at about 15. No terrain test (FLAT) in the horizontal direction, the sea breeze duration, South, North and West Sea inland propagation distance shorter 1~5km, wind intensity decreased about 1m/s, kinetic energy and sea breeze convergence intensity in the coastal area and southwest mountain large attenuation area; the vertical direction, the mobile location west sea breeze collision North direction, high return reduced height, wind thickness decreases, the vertical circulation intensity of 2~6m2/s2 decreases, the vertical velocity near the sea breeze front decreases more than 10cm/s. The sea breeze Valley in-phase stack effect also makes wind intensity disappear. The main mechanism is as follows: in power, caused by the mountain barrier, sea breeze forced uplift flow enhancement disappeared; in heat, the surface net radiation absorption is reduced, resulting in the release to the atmosphere in the sensible heat and latent heat fluxes were reduced by about 9%, this change has caused between the sea temperature the pressure differential is reduced, resulting in the weakening of the sea breeze. In addition, through two groups of shaving tests, we found that the range of convergence, intensity and kinetic energy decreased, and the vertical circulation structure of sea breeze changed correspondingly. The removal of the RMLM from the Li Mei mountain area had greater influence on the structure of the sea breeze than the removal of the Wuzhi mountains (RMWZ).
【作者单位】：南京信息工程大学气象灾害教育部重点实验室;浙江省气象台;
【基金】：公益性行业(气象)科研专项经费项目(GYHY201306009)
【分类号】：P461.3;P732
【正文快照】： 1引言海陆风是由海、陆加热快慢不均造成的一种沿海地区最常见的中尺度天气系统[1-5]。海陆风的研究不但广泛应用于沿海城市气象预报和边界层大气环境监测[6],更在天气学方面具有重要意义[7—10],特别是在海风前沿,会形成海风锋,可触发强对流天气[11—12],造成灾害。复杂地形

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