Understanding Radar Refractivity: Sources of Uncertainty

Quantifying Errors due to Frequency Changes and Target Location Uncertainty for Radar Refractivity Retrievals

Radar refractivity retrievals can capture near-surface humidity changes, but noisy phase changes of the ground clutter returns limit the accuracy for both klystronand magnetron-based systems. Observations with a C-band (5.6 cm)magnetronweather radar indicate that the correction for phase changes introduced by local oscillator frequency changes leads to refractivity errors no larger than 0.25 N ...

Recursive Bayesian electromagnetic refractivity estimation from radar sea clutter

[1] Estimation of the rangeand height-dependent index of refraction over the sea surface facilitates prediction of ducted microwave propagation loss. In this paper, refractivity estimation from radar clutter returns is performed using a Markov state space model for microwave propagation. Specifically, the parabolic approximation for numerical solution of the wave equation is used to formulate t...

Inversion for refractivity parameters from radar sea clutter

[1] This paper describes estimation of low-altitude atmospheric refractivity from radar sea clutter observations. The vertical structure of the refractive environment is modeled using five parameters, and the horizontal structure is modeled using six parameters. The refractivity model is implemented with and without an a priori constraint on the duct strength, as might be derived from soundings...

Refractivity Measurements from Ground Clutter Using the National Weather Radar Testbed Phased Array Radar

In warm seasons, convective precipitation initiation heavily depends on moisture near the surface [e.g., Dabberdt and Schlatter, 1996; Koch et al., 1997]. A necessary condition for an accurate prediction of convective rainfall is a good forecast of where and when convection will develop. Both prediction and understanding of convection is limited by the lack of high spatial and temporal resoluti...

Understanding uncertainty.