After years of planning, our voyage on the RV Investigator for the Years of Maritime Continent (YMC) will have finally happened by the time of this conference. This presentation will provide initial results from the Principal Investigators on board.

The international YMC project aims to tackle key remaining problems facing our understanding and simulation of the weather, climate and oceans of the Maritime Continent. For example, many global climate models show relatively large precipitation biases over the MC and poorly simulate its strong diurnal cycle of precipitation. These errors affect the model's ability to predict the weather and climate for days, seasons, and years ahead, both locally and globally. During 2017-2020 the YMC project is concentrating efforts of multiple countries to expedite the progress of improving understanding and prediction of local multi-scale atmosphere and ocean variability and its global impact through observations, modelling, and outreach. The main Australian contribution to YMC is a research cruise of the Marine National Facility's RV Investigator to the waters off northern Australia in October-December 2019, focusing on:

(1) Radar observations of atmospheric convection offshore from Warruwi, NT, for a period of 33 days to sample contrasting phases of the Madden-Julian Oscillation and its varying influence on the diurnal cycle.

(2) Detailed measurements of the ocean and atmospheric states and the associated air-sea interactions.

(3) Provision of a platform for supplementary projects focussing on (a) biogenic emissions from the ocean and their delivery to the stratosphere; (b) vertical mixing processes in the ocean to support improved parameterization in ocean models; and (c) observations of the water-mass transformations off Australia's Northwest Shelf for a period of 20 days.

Initial results from the collected observations will be provided.