The EFFECT OF LAND WIDTH ON LAND-SEA BREEZE
By Using WRF.4.0.3 & NCL
CASE1
CASE2
DEFAULT
ANALYZE1
KST: 2018-06-01_10:00:00
KST: 2018-06-01_11:00:00
KST: 2018-06-01_12:00:00
Looking at the graph in W-wind it is possible to see that strong ascending and descending airflow occurs at the interface of the coastline until 1-2 p.m. all at lm = 19, 38 and 55(default).
Fig. 1: Diurnal variation of wind speed above 10m form the surface at the different sampling sites where negative wind represents land breeze and positive wind speed represents sea breeze.
Table 1 : Geographical location and surface elevation of sampling sites in this study domain
The above graph shows the diurnal variation of sea breeze that varies with distance from shoreline.
It shows a relatively large sea breeze change in Sa1, located closest to the shoreline, and also records the largest sea breeze. And all the other graphs besides Sa1 are similar.
This shows that the closer spot to the shoreline, the stronger u-wind is to occur.
It is necessary to pay attention not only to the emission of flow, but also to what rotation exists in the flow. You can see that there is a close relationship between the rotating flow and the emission and therefore also the vertical movement. Therefore, you may want to diagnose whether the flow has the tendency or vortex to rotate. The change of u shall be calculated for diagnosing divergence and the change of w shall be calculated for diagnosing vortex. A strong flow of u that close to the ground will quickly move the end of the flow by the change of u at each altitude. As a result, it will cause rotation, so a vortex will appear, resulting in a rise of w.