Evidence of Extended Self-Similarity in Temperature Fields within the Mesoscale Range

Over the last several decades, the topic of inertial-range intermittency has been extensively studied throughout the turbulence community. Observational data from various laboratory experiments and numerous field campaigns were found to exhibit the signatures of intermittency. In order to quantify the degree of intermittency in low Reynolds number flows, a new concept called the extended self-similarity (ESS) was introduced in the 1990s. Several studies have documented that ESS not only facilitates robust quantification of intermittency, it also extends the scaling regime well into the dissipative range in comparison with other traditional approaches.

In recent works, it has been found that ESS also holds in the mesoscale range of atmospheric boundary layer wind fields. This development led us to examine whether or not the temperature field provides similar scaling characteristic. For our analysis, we examined long-term time series data from two different tower sites from Høvsøre, Denmark and in the foothills near Boulder, Colorado. During this presentation, we will document our findings along with their implications for mesoscale modeling. In addition, we will discuss various statistical convergence issues (using extreme value theory) which are commonly overlooked in the literature.