Acquisition: 7232004 Acquisition: 4212005
Acquisition: 7102005
Acquisition: 8112005 Acquisition: 1012006
Legend Figure 8. Distribution of NDVI in Karawang district.
4.1.5. Wind Velocity
Wind velocity is obtained from West Java and Jakarta areas using spatial interpolation kriging. The wind velocity data is obtained from 10 stations
surrounding Karawang district. Temporal resolution data is monthly average from 1995 to 2002. Wind velocity variation from January until December indicates
higher value in northern side of Karawang especially coastal area than southern side. Based on Beaufort scale from January to December wind velocity can be
classified into high, moderate, and low wind velocities. High category is wind velocity more than 6 ms, moderate 3-6 ms and low, less than 3 ms. High
category is dominant in northern side, moderate in center Karawang and low in southern area based on from topographic condition of Karawang district.
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Southern area of Karawang district is high land with air pressure higher than the northern area.
January February March
April May June
July August September
37
October November December
Legend
Figure 9. Distribution of wind velocity ms in Karawang district.
4.1.6. Air Temperature
Air temperature obtained by interpolation method from data collected around Karawang district shows different pattern and class for each month.
Average temperature in February is less than 25
o
C. This maybe due to the high temperature of Karawang district during the rainy season caused by very low
radiation to land surface and much radiation is emitted by the clouds. Trend of temperature from January until December is relative similar, but temperature
value is different. Northern area of Karawang is higher than southern area. The topography condition of Karawang determines temperature degree. North area
land altitude is less than 25 meter, while south area is higher. In general, air temperatures in Karawang are around 23-28
o
C.
38
January February March
April May June
July August September
39
October November December
Legend
Figure 10. Distribution of air temperature
o
C in Karawang district.
4.1.7. Solar Radiation
Solar radiation Rs is the amount of radiation reaching a horizontal plane. Solar radiation is also referred to as shortwave radiation. For a cloudless day, Rs
is roughly 75 of extra terrestrial radiation. On a cloudy day, the radiation is scattered in the atmosphere, but even with extremely dense cloud cover, about
25 of the extra terrestrial radiation may still reach the earths surface mainly as diffuse sky radiation. Extra terrestrial radiation Ra is the solar radiation received
at the top of the earths atmosphere on a horizontal surface. If the sun is directly overhead, the angle of incidence is zero and the extraterrestrial radiation is 0.0820
MJ m
-2
min
-1
. Solar radiation is also known as global radiation, meaning that it is the sum of direct shortwave radiation from the sun and diffuse sky radiation from
all upward angles.
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4.1.8. Net Radiation
