20 variations in climate cause most of the inter-annual variation in the strength of the
land carbon sink Hougthon, 2002. El Niño and La Nina are terms that many people have heard once or twice,
especially in reference to abnormal weather conditions, but many do not fully understand what these phenomena are. ENSO, more commonly known as El
Nino, is a climate event that occurs every three to seven years. It is caused by a rise in temperature of the Pacific Ocean as well as a change in surface pressure.
Predicting when the next ENSO event is going to occur can be difficult, but there are a number of early warning signs, such as an increased surface pressure above
the Indian Ocean Wikipedia, 2010. Figure 2.4 show the historical data of ENSO years occurred in world region.
Figure 2.4 Historical data of ENSO Years
In particular, El Nino events are associated with high temperatures and droughts in many tropical regions and have contrasted effects on precipitation
regimes in different world regions, either increasing or decreasing rainfall. In the western coastal regions of the Americas, an ENSO event is associated with
increased precipitation. The effects of an ENSO event can be seen across the world, with floods, droughts, and other weather events. Extreme changes in
weather and climate patterns can also affect local trade and industries in many countries.
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III. RESEARCH METHODOLOGY
3.1 Time and Location
This research has been conducted in period March until October 2010. Location of research is over Sumatra terrain. Figure 3.1 show the area of interest
of the research.
Figure 3.1 Location of the study area
3.2 Data Source
This research has used remote sensed and spatial data which are TERRA MODIS satellite data and meteorological data temperature and rainfall. The
MODIS satellite data collected by monthly since 2001 up to 2009. The MODIS data
were available
for free
download from
the site
ftp:e4ftl01u.ecs.nasa.govMOLT and also from the site which is;
https:wist.echo.nasa.gov~wistapiimswelcome and the meteorological data
were available
for free
download from
the site
http:www.esrl.noaa.govpsddatagridded .
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3.3 Required Tools
Several hardware and software used during this research project such are personal computer and printer, image processing software ENVI version 4.7,
MODIS Tool, Grads version 2.0, geographic information system software Arc Map version 9.2 and office application software Microsoft Office 2007 also
hand held GPS Garmin.
3.4 Methodology
3.4.1. Determine of Study Area
Study area of this research is Sumatera terrestrial. Sumatra also spelled Sumatera is an island in western Indonesia. Sumatera is the 5
th
highest island in the worlds island, and the third highest in the Indonesian archipelago at 473,481
km² with a population of 50,365,538. The longest axis of the island runs approximately 1,790 km 1,110 mil northwest
–southeast, crossing the equator near the center. At its widest point the island spans 435 km 270 miles and
administration of Sumatra terrains divided into ten provinces Wikipedia, 2010. The interior of the island is dominated by two geographical regions: the
Barisan Mountains in the west and swampy plains in the east. Most of Sumatra used to be covered by tropical rainforest, but economic development coupled with
corruption and illegal logging has severely threatened its existence. Conservation areas have not been spared from destruction.
3.4.2. Data Collecting
Remote sensing data of research study are used Terra MODIS satellite imagery data combining with meteorological data. Time series data used acquired
data from 2001 up to 2009. The acquisition of MODIS data are downloaded with free of charge from specific website. One requirement specification to make
MODIS data available is the availability of high speed internet connection to download the MODIS data.
