The 4^th Telecon of the ENSO Conceptual Model Working Group (WG) coordinated under CLIVAR Pacific Region Panel was organised on Jan.6, 2020. 16 members of the WG participated the meeting.

The telecon was kicked off by Jerome Vialard, coordinator of the WG, by reviewing the progress made so far by the WG on the definition of ENSO conceptual mode and the essential ENSO properties and mechanisms. The key messages and discussion points from the two presentations (i.e., Multiplicative noise & seasonal synchronisation of ENSO) made during the previous telecon were briefly summarised and further feedback received from the participants. Two new talks with contents closely linked to each other have been made during the telecon, i.e.: 1) Important ENSO nonlinearities (Soon-Il AN & co-authors) and 2) Niño / Niña asymmetry & extreme Niño genesis (Jon-Seong Kug & co-authors), followed by constructive discussions.

A doodle poll will be sent out to schedule the next telecon.