Atmospheric and Hydrospheric Sciences (A)
Session Sub-categoryAtmospheric Sciences, Meteorology & Atmospheric Environment (AS)
Session IDA-AS08
TitleMultiple scale structure and their interactions in Asian monsoon system
Short TitleScale interactions in Asian monsoon
Main Convener NameToru Terao
AffiliationFaculty of Education, Kagawa University
Co-Convener 1NameShinjiro Kanae
AffiliationSchool of Environment and Society, Tokyo Institute of Technology
Co-Convener 2NameJun Matsumoto
AffiliationDeaprtment of Geography, Tokyo Metropolitan University
Session LanguageE
ScopeAsian monsoon system consists of variablities in wide range of scales ranging from diurnal to decadal. The diurnal variability is common in Asian region which is related with the surface heating due to insolation. Various types of meso-scale to synoptic disturbances such as meso-scale convective systems, monsoon depressions and tropical cyclones account for major part of the precipitation in this region. Intraseasonal variations themselves have multiple time scales such as quasi bi-weekly oscillatiion (QBW) and the boreal summer intraseasonal oscillation (BSISO). We have diverse types of seasonalities in different regions in Asia. Interannual variabilities, such as ENSO-monsoon and climate projections, are another intrinsic time scales of Asian monsoon that attract researchers. These variabilities with specific spatio-temporal scales have mechanisms that are distinct from other types of variabilities. Our first target is to clarify the mechanisms of these specific variabilities. On the other hand, these multiple scale variabilities have strong interactions with each other. For example, diurnal variability interacts with all other variabilities with longer time scales. It has been shown that intraseasonal variabilities of precipitation highly depend on modulation of the activity of synoptic disturbances. Especially variabilities with time scales longer than weeks have strong interaction with boundary conditions such as land surface, cryosphere, and ocean surface with 'memories' longer than weeks. Especially, highly non-linear land surface-convection coupling controls sub-seasonal to seasonal (S2S) monsoon variabilities and limits our predictability. One of the focus of Asian precipitation experiment (AsiaPEX) is the multiple scale interaction in Asian monsoon system. We will exchange new development of studies on different time scales of variabilities and their interactions, and discuss on future development of our research activities.
Presentation FormatOral and Poster session
Joint with
Co-sponsoredJapan Society of Hydrology & Water Resources