Geoscience Reference
In-Depth Information
measurement for about 6 min. The PAL system is operated in Chiba
Prefecture Environmental Research Center, with its beam pointed
northward at the elevation angle of 38 degrees. The center is located on
the east of Tokyo bay, about 10 km south of Chiba University. There is an
industrial area and a busy load on the seaside (west of the center).
3. PAL Observation
The main advantage of the continuous and long-term observation is
capturing the local weather change that takes place in a time scale of several
hours. Especially, the system can monitor the onset and recovery of bad
weather conditions and changes in polluted airs. These features are largely
dependent on the site locations and conditions (urban/rural/mountains/
waters). Two examples of characteristic results from the viewpoint of long-
term cloud observation are shown in the following.
Figure 2 shows the result observed during 0-12 h local time on
October 7, 2006. The weather map of Fig. 2(a)
5
shows that the low
(a)
(b)
3
1.5
0
0
2
4
6
8
10
12
Time [hour]
Fig. 2. (a) Weather map over Japan on October 7, 2006. (b) 12-h cloud long-term
observation result: October 7, 2006. Temp. 21
◦
C, Hum. 35%.
