DRY SEASON IMPACT OF RAINFALL IN LA NINA

Although nowadays most of Indonesia is in a period of drought, but extreme weather actually hit several regions in the country. High-intensity rainfall accompanied by strong winds has triggered the occurrence of floods, landslides and lunge tornado in several areas should be dry due to ongoing dry weather.

The high rainfall during the dry season is a lot of benefit to many farmers who experienced famine in the previous year due to drought, because of the rain in this dry season of planting and harvesting them become more numerous. Rain in the dry season also provide many benefits such as adequacy of water supply needs for communities in areas that normally experience water shortages during the dry season. Although it is recognized that these conditions would likely lead to large losses for salt, and tobacco farmers, who expect the presence of plenty of sun in summer.

La Nina PHENOMENON

Such violations that trigger the occurrence of climate extremes in dry weather can not be separated from several factors such as rainfall controlling overheating in sea surface temperatures in Indonesian waters. Increasing sea surface temperatures in the waters of Indonesia caused more intensive process of evaporation and cloud formation that caused a lot of rain. In addition to sea surface temperature, extreme weather conditions in most parts of Indonesia in recent years due to La Nina phenomenon of global factors. La Nina causes buildup of air mass that contains a lot of water vapor in the atmosphere of Indonesia, so the potential for rain cloud formation becomes higher. As a result of the months in mid 2010 which should take place now instead drought torrential rains in various areas.

La Nina is a global natural phenomenon characterized by the condition of sea surface temperatures in the equatorial Pacific Ocean waters under normal values (cold), while sea surface temperature conditions in the waters of Indonesian Maritime Continent was above normal values (warm). La Nina phenomena can be known from the value of sea surface temperature anomaly in the waters of the Pacific Ocean. La Nina is the opposite of El Nino is a phenomenon of rising sea surface temperatures in the Pacific Ocean waters that affects the occurrence of long dry season and the length in Indonesia.

 

As opposed to the natural phenomenon of El Nino, La Nina during the sea surface temperature in the waters of the Pacific Ocean will become cold. Cooling sea surface temperatures will lead to high air pressure. Indonesian territory which lies west of the Pacific will experience a low air pressure caused by warming sea surface temperature in the vicinity. The condition causes air masses from the Pacific will flow into Indonesia that resulted in converging air masses rich in moisture, then the chances of rain in the Indonesian area becomes larger. The trend was the emergence of this phenomenon has been observed since the beginning of the dry 2010.

The prediction results Climatology Meteorology and Geophysics Agency (BMKG) and several monitoring agencies such as NOAA weather world (USA), BOM (Australia), Jamstec (Japan) showed the presence of negative sea surface temperature anomaly. On August until September 2010 been predicted La Nina phenomenon moderate, while in October 2010 until January 2011 will be a strong La Nina phenomenon.

La Nina phenomenon has affected the weather conditions in the atmosphere of Indonesia since early August 2010. When that time most of Indonesia is entering the dry season, but the fact still remains rain fell sporadically in various areas. Incidence of drought is the case rain makes the dry period in 2010 dubbed a wet dry. Based on data from monitoring results BMKG rainfall in various regions showed that rainfall during July and August 2010 over 50 mm per day. This means that almost most of Indonesia is experiencing rainfall with increasing frequency.

MOST EXTREME

Berasarkan wet dry note in Indonesia, the weather in 2010 is the most extreme conditions during the last 12 years. Monitoring data in Indonesian waters, sea surface temperature indicate that the La Nina in 2010 causing temperatures to most warm Indonesian waters during the last 12 years. La Nina has caused climate impacts in the form of significant deviations.

The phenomenon of overheating in sea surface temperature is almost uniform in all regions of Indonesia is similar to the climate condition in 1998. But when viewed in intensity, sea surface temperatures seem much higher in Indonesian waters. The divergence of the current climate could be said unique because in addition to the most extreme deviation, overheating in sea surface temperatures in the waters of Indonesia take place evenly.

Activity associated with La Nina, then the prediction BMKG indicate that extreme weather will still take place and hit the majority of the Indonesian territory until the end of this year. This prediction is based on the data of sea surface temperature Indonesian waters would continue to warm up to the moon in December 2010. Meanwhile predicted La Nina phenomenon will continue to dominant until March 2011 onwards towards neutral conditions in April 2011.

Some predictions are based on data and scientific facts mentioned above, all the more affirming a conclusion about the presence of La Nina this year, so every effort in to face the impact of the presence of La Nina weather extremes need to be prepared as early as possible. Public urged to improve disaster preparedness in the face of extreme weather impacts that may occur in the region occurred .***