BANYUMAS, Cilacap.info English – The southern Central Java region is forecast to experience a drought. Said BMKG weather analyst Tunggul Wulung Meteorological Station, Rendi Krisnawan.
“In general, dry season this year is predicted to rain, as has happened in last few days.” He said when contacted from Purwokerto, Banyumas Regency, Tuesday (7/7).
However, he said, rainfall in one decade (10 days, ed.) Is still in low category with intensity of rain that happened at that time mild to moderate.
BMKG has predicted that dry season in 2020 will be affected by weak La Nina.
He said based on a press release released by BMKG on June 27, 2020, BMKG Deputy Climatologist Herizal said that results of monitoring Pacific Ocean climate anomaly indicators, namely sea surface temperature of ENSO indicator area (Nino 3.4) until mid-June in Neutral conditions or temperature fluctuations sea level does not deviate more than 0.5 degrees Celsius from its normal climatological average.
“In release also mentioned that most of world meteorological institutions predict anomalies in sea level temperatures in Nino 3.4 until end of year range between Neutral and La Nina Weak.” He said.
In this case, weak La Nina condition is stated if sea level temperature deviation in ENSO indicator region is colder minus 0.5 degrees Celsius to minus 1.0 degrees Celsius from its normal climatology.
If La Nina conditions can occur, it can increase chance of increasing rainfall in parts of Indonesia so that dry season seems wetter because there is more rain than usual dry season.
Meanwhile, monitoring of Indian Ocean climate anomalies showed differences in sea surface temperatures in eastern Africa and west of Sumatra as a positive Indian Ocean Dipole Mode (IOD +) indicator in mid-June. IOD + is predicted to be Neutral in July to November 2020.
“We are still waiting for an official release from BMKG related to weak La Nina even though one of world meteorological institutions, namely Bureau of Meteorology (BOM) Australia today (7/7) has released about La Nina.” Rendi said.
In page https://www.bom.gov.au/climate/enso/#tabs=Pacific-Ocean it is stated that most of international climate models surveyed by BOM show that surface temperatures of central Pacific tropical sea level in NINO 3.4 region will cool in several coming month.
Two of eight models surveyed reached La Nina threshold during August, with three more models approaching threshold in September and November. The other three models remain clearer at neutral levels.
ENSO events – El Nino or La Nina – usually begin to develop during southern hemisphere experiencing autumn to winter, before strengthening in winter to spring. *