Monsoon research platforms over the ocean

Abstract

Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has been conducting observational research using several platforms such as ships, moorings, and autonomous surface vehicles (ASVs) to study atmospheric and oceanic variability related to the Asian monsoon. In particular, under the umbrellas of international field campaign program Years of the Maritime Continent (YMC) or international observation network Tropical Pacific Observing System (TPOS) as well as Observing Air-Sea Interactions Strategy (OASIS), we at JAMSTEC enhanced our activity through collaboration with many institutes and universities in Southeast Asia and Pacific islands. While in-situ observation network under such international collaboration and satellite-based observations cover wide area and long-term, our observation platforms themselves mainly focus on meso-scale (O(100 km)) in space and high resolution (e.g., hourly or finer) in time data collection, so that we can study from muti-scale interaction viewpoints. When we conduct a ship-based stationary observation, we often deploy several ASVs around the ship to form a meso-scale array. In addition, we have deployed the Philippine Sea mooring called PHSMO at 13°N, 137°E since December 2016 to capture warm pool atmospheric and oceanic conditions with high data sampling interval, which allows us to study diurnal cycles. In this article, we briefly introduce our monsoon research activities using these platforms. In addition, since our key platform research vessel “Mirai” retired her mission in December 2025, and JAMSTEC is now constructing a new Arctic research vessel “Mirai II”, we will also mention about the possibility of the new ship’s usage for monsoon research. Indeed, while her main mission is designed for Arctic research, her structure and equipped observation systems are adequate for other regions and missions including monsoon research.