2010 Fiscal Year Final Research Report

Detection of probability distribution and regimes in nonlinear systems with nonlinear dimension reduction methods

Research Project

Project/Area Number	21740344
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Single-year Grants
Research Field	Meteorology/Physical oceanography/Hydrology
Research Institution	Kobe University
Principal Investigator	NISHIZAWA Seiya Kobe University, 大学院・理学研究科, 助教 (40447892)
Project Period (FY)	2009 – 2010
Keywords	非線形次元削減
Research Abstract	The atmospheric system is a high dimensional nonlinear system and naive analyses of variability in the system is not easy due to the high dimensionality. In this study, I extract low dimensional manifolds from strongly nonlinear atmospheric variability, such as temperature in winter polar stratosphere and precipitation, with nonlinear dimension reduction methods. Those manifolds show asymmetry in physical quantities between positive and negative values, although the asymmetry cannot be represented with linear methods. Additionally I estimate existence probability distribution of state variables and clusters on the manifolds, and obtain possible regimes, though it is not statistically significant.

(4 results)