The Institute

Title: Self-Heating Effects and Response Time of Commercial PRTs: An Experimental Study in Controlled Liquid and Air Environments

Authors: G. Szklarz, A. Kowal

Journal: Measurement

DOI: 10.1016/j.measurement.2025.119652

Our research focuses on eliminating the fundamental discrepancy between ideal laboratory calibration conditions and the dynamic behavior of PRT sensors in the field environment. We demonstrated that the key challenge is sensor thermal inertia: the drastically slow response time in air (by two orders of magnitude) outweighs the self-heating effect, constituting the dominant source of error in dynamic climate measurements.

A key finding concerns the physical justification for this disparity. We proved that the difference in response time (τ_air/τ_lq) shows a strong correlation with the inverse square of the medium's thermal conductivity ratio (λ_air/λ_lq), which provides a physical basis for forecasting sensor behavior in variable atmospheric conditions. Concurrently, we developed and quantitatively verified a correction method that allows for the precise determination of sensor characteristics despite temperature drift during calibration under non-isothermal conditions.

These findings represent a direct contribution to uncertainty budgets in atmospheric measurements. Our research delivers quantitative metrics essential for developing advanced dynamic correction algorithms, enabling engineers and metrologists to construct more precise and reliable automatic weather stations capable of accurately monitoring atmospheric dynamics.