# Presentation: 644324

## SREF System Fall-2008 UpgradeJun Du, Geoff DiMego and Zolton Toth

- Dusan Jovic *for the new version of NMM and ARW models*
- Jun Wang, Henry Juang and Jongil Han *for the new version of RSM model*
- Binbin Zhou, Matt Pyle *for the new version of WRF bufr code*
- George Gayno *for modifying the land-surface-IC updating code*
- Geoff Manikin *for the WRF bufr breakout code*
- Binbin Zhou* for DTRA wind variance products*
- Ying Lin* for precipitation evaluation*
- Perry Shafran, Jeff McQueen *for grib-2-obs verification (to be done and not shown here)*

## Changes

**Model version upgrade for NMM (2.2), ARW (2.2) and RSM (2008)**
**Resolution increase to 32km for 40kmNMM, 45kmARW and 45kmRSM **
**Increase WRF membership: from 6 to 10 (5 NMM and 5 ARW) and reduce Eta membership from 10 to 6**
**Replace Ferrier microphysics scheme with WSM3 scheme for ARW members **
**More physics diversity for RSM members: replace Zhou cloud scheme with Ferrier scheme for 3 SAS members**
**Add aviation and wind-variance fields to ensemble products**
**Breakout SREF bufr output into individual stations for forecaster’s need**
**Replace the old wrfbufr with a new mpiio version of wrfbufr code**
**Adjustment of the overall SREF system such as ensemble products and bias correction due to membership alternation **

## Timelines

- Twice per day (09 and 21z) running of developer’s parallel system for systematic evaluation from June 16 to July 11 (4 weeks)
- The week of July 7: compile verification stats and prepare for EMC CCB briefing
- Code handover to NCO by July 22 upon approved by EMC CCB
- August and September: NCO parallel testing, field evaluation and implementation.

##      Modeling system code checking

## Old version vs. New version (precip fcst)

- 40km old NMM

- 32km new NMM

- 45km old ARW

- 32km new ARW

## Old version vs. New version (CAPE fcst)

- 40km old NMM

- 32km new NMM

- 45km old ARW

- 32km new ARW

## Old RSM vs. New RSM (precip and T2m)

- 45km old RSM

- 32km new RSM

- 45km old RSM

- 32km new RSM

## Large scale feature is similar between old and new versions, which indicates that the new NMM, ARW and RSM models work properly in codes.
New version shows more detailed spatial structures (especially in the mountainous West) as well as more intense in precipitation amount, which should be the case when model resolution increases. This should be an improvement over the old system although traditional measuring scores (such as rmse and TS) might suffer a bit (keep this in mind!). 

- New version shows more detailed spatial structures (especially in the mountainous West) as well as more intense in precipitation amount, which should be the case when model resolution increases. This should be an improvement over the old system although traditional measuring scores (such as rmse and TS) might suffer a bit (keep this in mind!).

##           Performance Evaluation

## T2m Bias Score: old vs. new version model (strong NMM cold bias gone!)

**T2m Bias Score: old vs. new version model (**_**strong NMM cold bias gone**_**!)**

**Old version of models:**

**New version of models:**

## Average RMSE of individual ensemble members

## Ensemble spread: Old vs. New SREF 

## Improvement of ensemble-mean fcst in terms of RMSE

## Improvement of ensemble spread in terms of Rank Histogram 

## Improvement of probabilistic fcst in terms of reliability

## Improved Resolution

- Higher PRSS (to be plotted)
- Higher BSS (to be plotted)

## Improvement over Spread-Skill Relation (measuring similarity between fcst error’s and ens spread’s spatial distributions) that is an important quantity but hard to be improved

## Slide 18

## SREF-21 Mean: ETS and Bias (from Ying Lin)

## ARW Component: ETS and Bias (from Ying Lin)

## NMM component: ETS and Bias (from Ying Lin)

## RSM component: ETS and Bias (from Ying Lin)

## Summary 

- Strong low-level temperature cold bias is gone for NMM members
- More accurate individual members (spread reduced and ensemble resolution improved)
- Improvement in ensemble mean forecast in general
- Improvement in ensemble spread quality in general
- Improvement in probabilistic forecasts in general
- Heavier amounts and more spatial details for precipitation forecast but no systematic change in large-scale pattern (could lower ETS due to details?).

## Technical details (to be added)

|  | Old dimension | New dimension | Old computing  | New computing |  |  |
| --- | --- | --- | --- | --- | --- | --- |
| NMM | (186,316,52) | (238,388,52) | 2N/32T
35min | 3N/80T
30min |  |  |
| ARW | (239,194,36) | (315,255,36) | 2N/48T
35min | 3N/80T
47min |  |  |
| RSM | (308,229,28) | (480,336,28) | 2N/32T
35min | 3N/80T
59min |  |  |