📆 Wednesday, May 21, 2025

🕐 12:00 noon CET

📍 Conference Room C2-212, C2 Campus Nord, Barcelona

ABSTRACT

The multifractal theory of turbulence provides a powerful framework that connects the scaling and geometrical properties of coarse grained fields in the limit of small scales with global statistics of the ow. As it is used here, this theory is based on three main contributions: Onsagers theory of ideal turbulence; the multifractal formalism; and different models of the turbulent cascade.

But, Dr Isern's implementation differs from common approaches in that it is based on velocity gradients rather than energy dissipation or velocity differences. If temperatures are used instead of velocities, the singularity exponents that characterize the behavior of coarse grained fields at small scales have a simple interpretation. Indeed, they can be seen as a proxy measure for the intensity of fronts, on the basis that the strongest fronts are those with the most marked singularity, hence, also those with the smallest singularity exponents. In this talk The speaker will review the basis of the multifractal theory of turbulence and show various examples of the insight obtained in different oceanographic problems such as the study of the energy cascade from in situ velocity measurements; the analysis of ocean models; or the comparison of different satellite products of Sea Surface Temperatures.

SPEAKER CV

Dr. Jordi Isern is is a researcher at the Institut de Ciències del Mar (CSIC), and the Head of Operational Oceanography at the Institut Català de Recerca per a la Governança del Mar.