Good news for now! If an early forecast by the Indian Met Observatory model MMCFS (Monsoon Mission Coupled Forecast system) released recently is to be believed, Odisha would not be going to witness a hotter March-April months this year courtesy the continuance of the la Nina phenomenon along the Pacific Sea, for which the State had this winter witnessed a chill season almost at par with 2011 when the la Nina was also in force.
The most revealing forecast made by the MMCFS data is that in association with the la Nina in force over equatorial Pacific Ocean, the Bay of Bengal (BoB) and the Arabian Sea have been cooler than the normal Sea Surface Temperature (SST) anomalies. And the significant prediction it made is the la Nina conditions would continue over the Pacific Sea till the middle of the year, i.e,, till August. Moreover, the IOD (Indian Ocean Dipole) mode index observations provide more supportive ambience to the prevailing la Nina conditions for a cooler SST in the BoB, the MMCFS model predicted. The effect: a cooler BoB could have a salutary effect in temperature moderation of the coastal landmass adjoining to it.
Though a myriad of studies have shown how El Nino/la Nina affects not only the temperature extremes but also the longer warm/cold spells in India, recent experiences of longer warm spell and abnormal temperature extremes were witnessed in the summer months of the respective years of 2015 and 2016 in Odisha that clearly vindicated the study results, given that the said years were preceded by El Nino years. Since the la Nina condition would continue till August and would be further aided by the salutary IOD factor, the dominant likelihood impact would be on moderation of temperature extremes in the coming summer months of March and April. Moreover, if the forecast holds ground till April, the data then suggest of an every likelihood of a normal monsoon over Odisha in 2018.
According to the MMCFS data, when cooler than SST anomalies with maximum negative SST anomalies are likely to remain along eastern and central parts of equatorial Pacific Ocean till August, Dipole Mode
Index (DMI) positive SST anomalies are likely to remain in the Arabian Sea and the BoB till June only and turn negative thereafter, which if turns true would not be a good sign for monsoon rainfall. However, as of now, the MMCFS prediction has ruled out a probability of the El Nino looming over the Pacific Sea.
Following the la Nina effect, Odisha witnessed below mean normal minimum temperatures this winter. As per data available with the local Met office, while the State in December 2017 witnessed an average minimum temperature of around 16 degree Celsius in the coastal region and around 8-14 degree in rest of the State; the average minimum temperature till January 19, 2018 was around 12-14 degree in the coastal region and around 8-12 degree in other regions. Even, the average mean temperature anomaly in the State in the two months of December 2017 and January 2018 have been (-) 1 to (-) 3 degree vis-a-vis the mean temperature for the period 1982-2010.
FAIR WEATHER!
la Nina means cooling of cool Pacific As Bay of Bengal is warmer, cool wind to flow in Warmer Indian landmass to see moist winds in