This session has four subthemes:
1) Nonlinear Dynamics of the Atmosphere, Ocean and the Coupled Climate System
Recent years have seen a substantial progress in the understanding of the nonlinear processes responsible for important dynamical aspects of the coupled atmosphere-ocean-climate system. In particular, the low-frequency variability (LFV) on seasonal to decadal time scales is now known to arise from irregular transitions between distinct atmospheric and oceanic regimes, as well as from the interaction between low- and high-frequency modes. Moreover, the application of the methods of dynamical systems theory (DST) has shown that a significant part of the LFV is governed by low-order nonlinear dynamics.
2) Climate Variability Across Scales
The climate is highly variable over wide ranges of scale in both space and in time. As a general rule, the climate variations recorded in time series or spatial distributions are expected to depend fairly systematically on time and spatial scales at which they are considered. Such variations need to be accounted for in uncertainty estimates.
This session brings together scientists from the nonlinear geoscience community with climatologists and paleoclimatologists from the modelling and proxy-data acquisition communities (particularly the PMIP and the PAGES Climate Variability Across Scales working group) with the aim to develop tools for understanding, comparing and modelling time series and spatial distributions over wide scale ranges so as to better understand and quantify the climate variability in time and space while taking into account intrinsic uncertainties.
3) Multifractals and singularity analysis in mineral exploration and environmental assessment
In recent years there has been a significant increase in nonlinear modeling studies applied to geological, geophysical, geochemical and remote sensing data for mineral exploration and environmental assessment. Various forms of multifractal modeling including the application of universal multifractals to geophysical and geochemical survey data have been proven to provide useful new types of information. Singularity analysis is an offshoot of multifractal modeling. It allows the delineation of local anomalies which are superimposed on broader regional map patterns commonly constructed by well-known contouring methods such as moving averaging, inverse distance weighted interpolation or various Kriging methods. Local singularity analysis can target centers of local enrichment or depletion of chemical elements in the Earth’s crust.
4) Scaling fluctuations in the ocean and atmosphere
Oceanic and atmospheric fields show deterministic and stochastic fluctuations over a very large range of scales. Due to the influence of turbulence and other forcing, such fluctuations often possess fluctuations over some given range of scales. This session focuses on methods, observations, and data analyses aiming to identify such scaling ranges and characterize them.