Ringing a warning bell for India, a UN advisory has said that southern India could continue to experience higher than normal rainfall and this could cause further flooding, particularly urban flooding, in certain location in Southern India, due to El Nino weather pattern.
The Third Advisory Note on El Nino issued jointly by the UN Economic and Social Commission for Asia and the Pacific and the Regional Integrated Multi-Hazard Early Warning System for Africa and Asia (RIMES) comes at a time when Tamil Nadu is reeling under the fury of floods caused by rains.
According to the advisory, higher than normal rainfall is likely to continue over the southern India and South Asia, including the Maldives and Sri Lanka during the winter period (December 2015 to February 2016), though lower rainfall is expected over the northern part of South Asia.
“Sri Lanka and southern India could continue to experience higher than normal rainfall as per the winter outlook issued by WMO (World Meteorological Organisation) and this could cause further flooding, particularly urban flooding, in certain location south India, severe floods have already been reported in several parts of Tamil Nadu during November and December 2015, inundating most areas of Chennai,” it said.
The advisory warned that El Nino will likely continue to cause significant drought during the period from November 2015 to April 2016, spanning southern parts of Sumatra, Java and eastern parts of Indonesia, central and southern parts of the Philippines and Timor-Leste.
Development of El Nino conditions are caused by rise in sea surface temperatures in the equatorial Pacific and El Nino condition is linked to weakening of monsoon.
Quoting some studies by Indian scientist, the advisory said in general, El Nino results in suppressed rainfall conditions during the June to September months, though for some El Nino years there may be no impact on rainfall.
“Food grain production is highly vulnerable to ENSO events, resulting in significant falls in crop production (especially rice). In 2014, seasonal rainfall was around 12 percent less than normal, which affected food grain production by 10 million tons. In 2015, seasonal rainfall was around 14 percent lower than normal, with water levels in reservoirs down by 30 percent,” it said.
It further said that by comparison, and demonstrating the complexity of El Nino, the southern part of India around the peninsular often experiences increased rainfall conditions during October to December during El Niño events, which can create a favorable crop production environment but also flooding in certain pockets of southern India.
The UN said that regional cooperation is critical to ensure better understanding of El Nino associated risks. Sharing and exchanging risk information among stakeholders and creating appropriate enabling mechanisms to act on risk information would help address and better prepare for the impacts of El Nino.