Preliminary Results from Project Athena Project Athena Team Presentation to the COLA Scientific Advisory Committee April 12, 2010 Very (Major Computing Operations Ended 0800 April 1)

Many Thanks To … ECMWF – Mats Hamrud – Thomas Jung – Martin Miller – Tim Palmer (co-PI) – Peter Towers – Nils Wedi NICS – Phil Andrews (co-PI) – Troy Baer – Matt Ezell – Christian Halloy – Dwayne John – Bruce Loftis – Kwai Wong Cray – Pete Johnsen – Per Nyberg NSF – AGS: Jay Fein – OCI: Steve Meacham, Rob Pennington JAMSTEC/U. Tokyo – Chihiro Kodama – Masaki Satoh (co-PI, U. Tokyo) – Hirofumi Tomita (co-PI, JAMSTEC) – Yohei Yamada COLA – Deepthi Achutavarier – Jennifer Adams – Eric Altshuler – Ben Cash – Paul Dirmeyer – Brian Doty – Bohua Huang – Emilia Jin – Jim Kinter (PI) – Larry Marx – Julia Manganello – Cristiana Stan – Tom Wakefield

Many Thanks To … ECMWF – Mats Hamrud – Thomas Jung – Martin Miller – Tim Palmer (co-PI) – Peter Towers – Nils Wedi NICS – Phil Andrews (co-PI) – Troy Baer – Matt Ezell – Christian Halloy – Dwayne John – Bruce Loftis – Kwai Wong Cray – Pete Johnsen – Per Nyberg NSF – AGS: Jay Fein – OCI: Steve Meacham, Rob Pennington JAMSTEC/U. Tokyo – Chihiro Kodama – Masaki Satoh (co-PI, U. Tokyo) – Hirofumi Tomita (co-PI, JAMSTEC) – Yohei Yamada COLA – Deepthi Achutavarier – Jennifer Adams – Eric Altshuler – Ben Cash – Paul Dirmeyer – Brian Doty – Bohua Huang – Emilia Jin – Jim Kinter (PI) – Larry Marx – Julia Manganello – Cristiana Stan – Tom Wakefield

Qualitative Analysis: 2009 NICAM Precipitation May 21-August 31

May Tropical Cyclone Aila 23May09 25May09 21May09 NICAM simulation accurately predicted development, evolution and track of Aila over 5- day period

Qualitative to Quantitative: Beyond Animations Athena Catalog – 8 NICAM (7 km) Boreal summer cases – 9 IFS T2047 (10 km) Boreal summer cases – 20 IFS T month hindcasts – 48 IFS 13-month hindcasts at T1279 (16 km), T511 (40 km), T159 (128 km) – 50 year IFS AMIP run at T1279, T511, T159 – 50 year IFS timeslice run at T1279, T511, T159 – Multiple ensemble members for select seasons at T1279, T511, T159 Sufficient data for quantitative analysis

7km: NICAM JJA Mean Rainfall at native resolution (8 seasons)

10km: IFS T2047 JJA Mean Rainfall at native resolution (8 seasons)

40 km: Chen et al. 0.5 degree JJA Mean Rainfall (8 seasons)

25 km: TRMM JJA Mean Rainfall (8 seasons)

128 km: IFS T159 JJA Mean Rainfall native resolution (8 seasons)

JJA Mean Precip Diurnal Cycle Amplitude (mm/day) Diurnal amplitude accurately represented

JJA Mean Precip Diurnal Cycle Phase (local hour of max) Qualitative differences between IFS and NICAM Plateau in improvement with resolution?

IFS JFM Mean Snow Depth CONUS Transect at 40 N Interpolated high-resolution agrees with native T159 Orographic features are not represented

Coarse Native Decreasing Resolution Biases Distribution

LARGE BIASES REMAIN

JJA Mean Diurnal Cycle Phase (local hour of max) NICAM more accurate in reproducing phase, despite large bias in amplitude

Atmosphere-Ocean Interactions Modest improvement with resolution All data at T159

Clear improvement in representing interannual variability

Tropical Cyclones Identification and Calibration Hodges Method:  850-hPa relative vorticity max  Lifetime > 2 days  Cyclogenesis in 0-20N over land and 0-30N over oceans  ξi / ξv, where  ξi is the 850-hPa relative vorticity threshold,  ξv is the threshold for difference in vorticity between 850 hPa and 250 hPa  ξi / ξv must hold for 1 day OBS: data from IBTrACS for OBS-STR: TCs with max 10-min sustained winds > 15.4 m/s (30 kt)

Track Density (Northern Hemisphere) Observed - Bengtsson et al IFS T1279 IFS T511 IFS T159 Similar results with model dependent calibration

Track Density (Northern Hemisphere) Observed - Bengtsson et al IFS T1279 IFS T511 IFS T159 Applying T1279 calibration to T159 eliminates most storms

Track Density (Northern Hemisphere)

Maximum Attained Wind Speed ( ) NAtl WPac Observed IFS T511 and T1279 Distribution shifts with resolution Still weaker than observed IFS: 10-m wind speed (10-min ave (T1279), 15-min ave (T511)) MJJASON season, IFS NAtl: 10-m wind speed (10-min ave (T1279), 15-min ave (T511)), MJJASON season,

TS CAT 1 CAT2 CAT3 CAT4 CAT5 TS CAT 1 CAT2 CAT3 CAT4 CAT5 IFS T storms 7.5 min avg NICAM GL storms 30 sec avg Maximum Attained Wind Speed JJA Simulations T2047 distribution similar to T1279 – more evidence of a plateau? Higher percentage of strong storms in NICAM

Summary – Unique data set and analysis opportunities Small fraction at COLA Fall catalog in archive at NICS – Precipitation Generally Improved Orographic features evident Diurnal cycle can be well-represented – No clear winner among models – Plateau in benefit of resolution with parameterized convection? Large tropical biases remain – Resolution is not a panacea

Summary (cont’d) – Impact of Resolution on Large Scales Improved blocking and synoptic statistics Atlantic air-sea coupling Important implications for climate change – Tropical cyclones improve with resolution What are T159 ‘cyclones’? Impact of non-parameterized convection? – Support for other COLA activities Monsoon predictability Maya express at T1279? MUCH more to come