10:45 〜 11:00
[AAS01-01] The utility of EarthCARE CPR Doppler velocity observations for evaluating the representation of convective motions in regional and global high-resolution models
★Invited Papers
キーワード:EarthCARE, Doppler velocity, convection, vertical air motion
The EarthCARE mission features the first Cloud Profiling Radar (CPR) with Doppler capability. The Doppler capability of the CPR is expected to provide unique global observations of convective vertical air motion in shallow and deep convection. Two key challenging questions need to be addressed before we can assess the usefulness of the CPR Doppler velocity measurements for evaluating the representation of convective dynamics in high-resolution models. The first is related to the performance and quality of the CPR Doppler velocity measurements in shallow and deep convection and the second is related to the development of an objective methodology for using these observations for evaluating high-resolution regional and global numerical models.
To address the first part, CloudSat observations and simulations of the EarthCARE CPR are utilized to quantify the part of the spectrum of convective air motion distribution that will be sampled by the CPR. The EarthCARE CPR has a narrow instantaneous field of view which minimizes the sampling area effect on the determination of the updraft’s properties such as magnitude and area. On the other hand, the CPR operates at 94 GHz, a frequency where radar signal propagation is affected by strong attenuation and multiple scattering, especially in deep convection. Furthermore, although the EarthCARE CPR is very sensitive (-35 dBZ), the Doppler velocity measurements have good quality for radar reflectivity values above -15 dBZ.
In this presentation, we will quantify which part of the deep convective systems will be sampled by the CPR and evaluate the performance of the CPR in shallow oceanic convection. To address the second part of our investigation, a state-of-the-art simulator is applied to a wide range of numerical model output from regional to global storm resolving models are used to provide a synthetic view of convective dynamics as captured by the EarthCARE CPR. A fast surrogate emulator for an apples-to-apples comparison between the synthetic EarthCARE CPR Doppler velocity measurements and the model output is presented.
To address the first part, CloudSat observations and simulations of the EarthCARE CPR are utilized to quantify the part of the spectrum of convective air motion distribution that will be sampled by the CPR. The EarthCARE CPR has a narrow instantaneous field of view which minimizes the sampling area effect on the determination of the updraft’s properties such as magnitude and area. On the other hand, the CPR operates at 94 GHz, a frequency where radar signal propagation is affected by strong attenuation and multiple scattering, especially in deep convection. Furthermore, although the EarthCARE CPR is very sensitive (-35 dBZ), the Doppler velocity measurements have good quality for radar reflectivity values above -15 dBZ.
In this presentation, we will quantify which part of the deep convective systems will be sampled by the CPR and evaluate the performance of the CPR in shallow oceanic convection. To address the second part of our investigation, a state-of-the-art simulator is applied to a wide range of numerical model output from regional to global storm resolving models are used to provide a synthetic view of convective dynamics as captured by the EarthCARE CPR. A fast surrogate emulator for an apples-to-apples comparison between the synthetic EarthCARE CPR Doppler velocity measurements and the model output is presented.