Pune: The consensus statement presented at South Asian Climate Outlook Forum (SASCOF-12) sessions states that there would be normal rainfall during the southwest monsoon season this year (June to September 2018) over most parts of South Asia.
The statement was released on Friday at Indian Institute of Tropical Meteorology (IITM).
However, some areas of east-central India and southeastern parts of the region are likely to experience above normal rainfall while some areas of southern, northwestern and northeastern parts of South Asia are likely to experience below-normal rainfall.
This consensus outlook for the 2018 southwest monsoon rainfall over South Asia has been developed through an expert assessment of the prevailing global climate conditions and forecasts from different climate models from around the world.
The statement mentioned that currently, weak La Niña conditions are prevailing over the Pacific Ocean.
There is a strong consensus among experts about the possibility of La Niña conditions turning to ENSO neutral conditions during the beginning of the southwest monsoon season.
Some of the global models are also indicating a possibility of setting of El Niño conditions during the last part of the monsoon season or thereafter.
It is recognised that there is large uncertainty in the forecasts done at this time of the year, particularly regarding the time of the transition from La Niña to ENSO neutral conditions or setting of the El Niño conditions thereafter.
However, other regional and global factors can also influence the monsoon rainfall patterns over the region, said the statement.
Commenting on the statement, KJ Ramesh, Director General of Meteorology said that various factors influence the monsoon.
“Monsoon is the result of the difference between temperatures of the land and the sea. Snow cover in the northern hemisphere (NH) also plays a vital role,” said Ramesh.
“The snow covered area averaged over the northern hemisphere in March was above normal and was the 22nd highest among the March months of the last 52 years. The NH snow cover during winter and spring has a negative relationship in general with the subsequent Asian summer monsoon. Hence, this factor is favourable,” he further added.
The consensus outlook for the 2018 southwest monsoon rainfall over South Asia has been developed through an expert assessment of the prevailing global climate conditions from around the world. The statement mentioned that currently, weak La Niña conditions are prevailing over the Pacific Ocean.