Geoscience Reference
In-Depth Information
direct association of heat process in the coastal region with wind and tem-
perature generated by sea-land breeze. Pielke,
3
Choi
4
,
5
and Palmer
et al.
6
stated both orographic effects with high mountains and the roll of sea breeze
on atmospheric circulations near the coast, under the horizontal tempera-
ture contrast of air over land and sea surfaces. Kondo
et al.
7
emphasized
that more sensible heat had to be accumulated in the valley region than
over the mountainous areas on calm and cloudless days, due to much larger
amplitudes of the diurnal variations of atmospheric temperature and sur-
face pressure at the bottom of a valley.
Whiteman
8
and Holton
9
explained thermally developed wind system in
mountainous terrain through observation and Kuwagata
et al.
10
discussed
the daytime boundary layer heating process over complex terrain under fair
weather. Baik
et al.
11
also investigated dry and moist convection forced by
an urban heat island, but they are confined to explain the accumulation of
heat in the inland basin, not consider thermal accumulation in the moun-
tainous coastal region. Choi and Kim
12
verified the formation of nocturnal
thermal high in inland basin near Taegu city, Korea by numerical simula-
tion on thermally induced circulation. This study is focused on the diurnal
variation of sensible heat flux in the mountainous coastal sea, using a three-
dimensional numerical model, which can greatly influence upon sea and air
temperature distribution over the coastal sea under the effects of steep high
mountains and coastal inland.
2. Numerical Analysis and Data
Topographical feature of the study area consists of inland plain, high steep
mountains, narrow inland basin and sea. In a coarse-mesh domain, Tae Bak
mountains lie from south toward north along the eastern coast of Korea
and another several branch mountains stretch out toward south-west off
the mountains. In a fine-mesh domain, the study area consists of complex
terrains characterized by forest in a high steep mountain (Mt. Taeguallyung;
865 m) in the west, Kangnung city in the narrow plain of the center and
sea in the east.
A nonhydrostatic grid point model in a complex terrain-following coordi-
nate (
x
,
y
,
z
∗
) was adopted for a 48 h numerical experiment from 06:00 LST
(Local Standard Time = 9 h + UTC), August 13 to 06:00 LST, August 15,
1995, by Hitachi super computer at Japan Meteorological Research Insti-
tute (JMRI).
13
,
14
Two different domains consist of 50
×
50 grid points with
a uniform horizontal interval as 20 km in a coarse-mesh model and 5 km
