1 / 15

Anomalous Propagation and Radar Observations: Insights from the Carpe Diem Project

This report presents findings from the Carpe Diem Project, focusing on anomalous propagation (AP) observed through radar technology in Bologna from December 1, 2004. The analysis includes worldwide VRG models, calibration against radiosonde observations in Barcelona, and sensitivity studies on radar beam blockage. Key summaries highlight the robustness of blockage corrections and the relationship between VRG variability and induced errors. Additionally, the integration of numerical weather prediction (NWP) and radiosonde data shows improvements in forecasting accuracy for refractivity profiles.

arva
Télécharger la présentation

Anomalous Propagation and Radar Observations: Insights from the Carpe Diem Project

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CarpeDiem Project, Bologna 1/12/2004 WP-6 Anomalous Propagation

  2. CarpeDiem Project, Bologna 1/12/2004 RADAR OBSERVATIONS & ANOMALOUS PROPAGATION PBEZTPPI06_VRG-112 PBEZTPPI06_VRG-043

  3. CarpeDiem Project, Bologna 1/12/2004 World-wide VRG 1km, August (ITU, 1997)

  4. CarpeDiem Project, Bologna 1/12/2004 BARCELONA RPC COMPUTED FROM RADIOSONDE OBSERVATIONS (RAOB): - 00 Z & 12Z (41.38ºN, 2.12ºE) - VAISALA RS-80 SONDES - 10 S SAMPLING - 1997 TO 2002 (2485 OBS) RAOB DATA READ RAOB QUALITY CONTROL 85% VALID RAOB PROFILES (Ns, VRG,..) - POSTPROCESSING - STATISTICAL ANALYSIS - COMPARISON VRG vs Ns PROCESS RPC RPC REPORT WRITE RPC REPORT RAOB PROCESSING BLOCK DIAGRAM Weather Radar anomalous propagation (AP)

  5. CarpeDiem Project, Bologna 1/12/2004

  6. CarpeDiem Project, Bologna 1/12/2004 YEARLY DIURNAL RANGE SUMMER DIURNAL RANGE NEXRAD beam blockage correction sensitivity analysis (Bech et al. JTECH 2003) ±0.05º ±0.10º ±0.05º Radar beam blockage and anaprop in complex terrain

  7. CarpeDiem Project, Bologna 1/12/2004 VRG = N / z ITU (1997), Steiner and Smith (2002) ID = 78 z - M Johnson et al. (1999) Different MASS model domains. November 2002 to February 2003 (183 cases) Forecasts of refractivity profiles based on 12 & 24 H MASS model output 00 & 12 Z RAOB Modified refractivity forecast and observed profile. Use of NWP forecasts & RAOB to monitor AP

  8. CarpeDiem Project, Bologna 1/12/2004 Use of NWP forecasts & RAOB to monitor AP

  9. CarpeDiem Project, Bologna 1/12/2004

  10. CarpeDiem Project, Bologna 1/12/2004

  11. CarpeDiem Project, Bologna 1/12/2004

  12. CarpeDiem Project, Bologna 1/12/2004 Ground clutter and beam blocking – representativeness of different datasets to reproduce the beam path 9 July 2003, 00:00 UTC datasets: RAW RADIOSOUND. DATA TEMP DATA LOKAL MODEL DATA (LM) LOWER LIMIT OF 3 dB - BEAM

  13. CarpeDiem Project, Bologna 1/12/2004

  14. SUMMARY (1/2) • Beam blockage vs VRG variability simulated with an interception function. • Blockage corrections were generally robust. • VRG induced errors comparable to antenna alignment errors. • Clutter echoes may be cleaned BUT echo heights may still be affected for some applications requiring precise height measurements (VAD assimilation,..).

  15. SUMMARY (2/2) • Original model forecasts were biased towards subrefraction. • Model output anticipated correctly average conditions & tendency. • New modified forecasts improved significantly verification scores. • In some cases RAOB persistency yielded better results than NWP forecasts.

More Related