1 / 18

High resolution COPE simulations

This study focuses on the High-Resolution COPE simulations, conducted by Kirsty Hanley and colleagues, analyzing convective precipitation processes in organized convective systems over Southwest England during July and August 2013. The project aims to deepen the understanding of physical processes involved in convective precipitation, improve the representation of these processes in operational numerical weather prediction (NWP), and enhance data assimilation for better forecasting of convective precipitation events that could lead to flash flooding.

belle
Télécharger la présentation

High resolution COPE simulations

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. High resolution COPE simulations Kirsty Hanley, Humphrey Lean MetOffice@Reading, UK

  2. COPE • Field campaign to study the production of precipitation in organised convective systems over SW England during July and August 2013

  3. Aims of COPE • Understand the physical processes involved in convective precipitation. • Improve the representation of microphysical processes in operational km-scale NWP. • Improve the exploitation of data used for operational assimilation. • Leading to improved forecast of convective precipitation that can cause flash flooding.

  4. COPE IOPs Sea breeze

  5. Model setup – UM vn8.2 PS32 UKV – 1.5km grid length, 70 levels, 2D subgrid turbulence scheme, BL mixing in vertical. 500m model – 500x400 km 200m model – 300x200 km 100m model – 150x100 km High res models: 140 vertical levels, 3D subgrid turbulence scheme, RHcrit is 0.97 (0.91) in 1st few layers decreasing smoothly to 0.9 (0.8) at ~3.5km. Set of nested models.

  6. 18 July – popcorn convection up to 9km

  7. 25 July – line of showers up to 3km

  8. 29 July – organised convective line over SW peninsula

  9. 3 August – convergence line

  10. Summary 1 • Saw quite high rainrates from warm rain. • Cells appear to get smaller as grid length is reduced – this agrees with work done for DYMECS. • The high resolution models maybe produce too much rain. • Lines appear to break up in 200m and 100m model – why? • Are the cells getting smaller a result of the updrafts getting narrower or is it a micophysics issue? • Look at a sea breeze case without precipitation to isolate vertical velocity.

  11. July 5 – sea breeze convergence

  12. July 5 – sea breeze convergence

  13. July 5 – sea breeze convergence FAAM obs Different colours are different times

  14. July 5 – sea breeze convergence 500m UKV Vertical velocity at 325m 13Z 200m 100m Different scale!

  15. July 5 – sea breeze convergence 1000 UKV 0 -0.5 0 0.5 1 1.5 Vertical velocity at 13Z 1000 500m 0 2 -2 0 4 6 1000 200m 0 2 -2 0 4 6 1000 100m 0 -2 0 2 4 6

  16. July 5 – sea breeze convergence 1000 UKV 0 -5 0 5 Westerly wind at 13Z 1000 500m 0 0 -5 5 1000 200m 0 0 -5 5 1000 100m 0 -5 0 5

  17. July 5 – sea breeze convergence

  18. Summary 2 and Future Work • Updraft magnitude and width compares reasonably well between the observations and the high resolution models – how does cloud width compare? • Compare simulations with lidar and King Air measurements. • Identify key areas of difference between models and observations: • Timing, location, size and intensity of cells.

More Related