1 / 11

Tropical Cyclone Environment Model Diagnostics

Tropical Cyclone Environment Model Diagnostics . Mark DeMaria NOAA/NESDIS/STAR Brian McNoldy , Kate Musgrave, Andrea Schumacher CIRA/CSU HFIP Annual Review, AL Nov. 8-9, 2011. Outline. Motivation Verification of storm environmental parameters from GFS, HWRF, GFDL and COAMPS-TC

cale
Download Presentation

Tropical Cyclone Environment Model Diagnostics

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. Tropical Cyclone Environment Model Diagnostics Mark DeMaria NOAA/NESDIS/STAR Brian McNoldy, Kate Musgrave, Andrea Schumacher CIRA/CSU HFIP Annual Review, AL Nov. 8-9, 2011

  2. Outline • Motivation • Verification of storm environmental parameters from GFS, HWRF, GFDL and COAMPS-TC • Fitting LGEM to the HWRF and GFDL regional models

  3. Regional Model Intensity Error Sources • Large scale environmental prediction errors • Compare large scale predictors from SHIPS diagnostic code • GFS, HWRF, GFDL, COAMPS-TC • Incorrect model response to large scale forcing • Fit HWRF, GFDL forecasts to simplified LGEM to determine model response to large scale forcing • Compare with GFS data fit to observed intensity changes Katia Maria Ophelia Philippe

  4. Verification of Large Scale Predictors for 2011 Atlantic Cases Shear T200 U200 Low Level RH

  5. Large Scale Variable Biases

  6. Fitting Model Forecasts to LGEM to Assess Response to Large-Scale Forcing V = max wind, t = time Vmpi = Maximum Potential Intensity (from SST along track) n = Shape parameter (constant) β = Time scale of relaxation to MPI (constant) κ = Growth rate , function of large scale variables For constant Vmpiand κ steady state solution (Vss) Vss = Vmpi(κ/β)1/n V/Vss t/κ

  7. Simplified LGEM • Assume κ is linear function of 2 variables κ = a0 + Sa1 + Ca2 S = 850-200 hPa shear magnitude C = Convective instability (CAPE modified by entrainment) • Use adjoint LGEM model to find 5 parameters β, a0 , a1 , a2 , n • Calculate (Vss/Vmpi) from sample mean S, C

  8. Results of LGEM Fit • Were large-scale controls different in 2011 than previous year? • Compare 2000-2010 LGEM parameters to 2011 • Is intensity in HWRF and GFDL modulated by large scale? • Fit with model intensity and model S and C

  9. 2011 Comparison to 2000-2010

  10. HWRF and GFDL Fits

  11. Preliminary Conclusions and Future Plans • HWRF • Large scale environment has slight favorable bias • Response to environment slightly greater than observed • Both contributed to high intensity bias • GFDL • Large scale environment has “unfavorable” bias • Response environmental forcing much greater than observed • Vortex response overcomes unfavorable environment • Extend analysis to COAMPS-TC and other regional models • Add parameters to LGEM • Verify synthetic IR data

More Related