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Presentation on MM5 performance evaluation for winds, temperature, humidity, clouds, and fog with recommendations for August and November using 4/12-km grids. Detailed analysis of meteorological data from Wishram Camera for August and November 2004.
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CRGAQS:Meteorological Modeling Presentation to the SWCAA By ENVIRON International Corporation Alpine Geophysics, LLC August 17, 2006
Today’s Presentation • Further additional evaluation of MM5 performance • Compare 4/12-km results • Compare Final (Run 6) against UW (Run 3) • Analyses conducted for: • 4-km surface wind fields in Gorge area • Wind, temperature, humidity time series at west, central, east sites
Today’s Presentation • PBL/mixing heights • Cloud cover and fog on 4-km grid • Wind, temperature, RH at Wishram
Conclusions • Winds similar among: • 4-km and 12-km grids • Final Run 6 and UW Run 3 • Possible slight edge to Run 6 4-km winds due to observation nudging • Temperature/humidity: • UW Run 3 better for November • Final Run 6 @12-km better for August
Conclusions • Clouds/fog: • Unimportant for August episode • Very important for November episode • UW Run 3 generates more low clouds/flog • But less high large-scale cloudiness • Recommendation: • Use Final Run 6 12-km for August • Use UW Run 3 4-km for November
Wind Performance, August 2004 • Hi bscat 8/10-8/16, 8/19 • Similar performance, both runs, both grids • Poor performance at central sites 8/10-8/13 • Wind opposite direction • Good performance 8/14-8/22 • Maybe too light on some days
Wind Performance, November 2004 • Hi bscat 11/8-11/13 • Similar performance, both runs, both grids • Final Run 6 a bit better (nudging?) • Overall better performance than for August episode • Very good performance over 11/8-11/13 • Some stagnation leads to wind direction errors • Some windy periods are too light
August 2004 notes at Wishram camera: Cloud Cover 8/10 Scattered clouds < half of sky, No layered haze 8/11 No clouds, No layered haze 8/12 Scattered clouds < half of sky, No layered haze 8/13 No clouds, No layered haze 8/14 (high) Overcast > half of sky, No layered haze 8/15 Scattered clouds < half of sky, No layered haze 8/16 (high thin) Overcast > half of sky, No layered haze 8/17 (high thin) Overcast > half of sky, No layered haze 8/18 (high thin) Overcast > half of sky, No layered haze 8/19 Scattered clouds < half of sky, No layered haze 8/20 (high thin) Overcast > half of sky, No layered haze 8/21 (high) Overcast > half of sky, No layered haze 8/22 Overcast > half of sky, No layered haze
August 2004 Cloud Cover • Performance appears adequate • MM5 cannot replicate high thin/wispy cirrus • MM5 usually underperforms for scattered small-scale afternoon cumulus • These should not play significant role in regional PM chemistry • Choice of MM5 not important
Wishram Camera August 14, noon Pristine
Run 6 Low High
UW Run 3 Low High
November 2004 notes at Wishram camera: Cloud Cover 11/3 Scattered clouds < half of sky, No layered haze 11/4 No clouds, Ground-based layered haze only 11/5 (high thin) Overcast > half of sky, No layered haze (hazy) 11/6 Scattered clouds < half of sky, Ground-based layered haze only 11/7 Overcast > half of sky, No layered haze (hazy) 11/8 Overcast > half of sky, Weather concealing scene (thick haze) 11/9 Overcast > half of sky, Weather concealing scene (thick haze) 11/10 Overcast > half of sky, Weather concealing scene (fog) 11/11 Overcast > half of sky, Weather concealing scene (thick haze) 11/12 Overcast > half of sky, Weather concealing scene (fog) 11/13 Overcast > half of sky, Weather concealing scene (thick haze) 11/14 Overcast > half of sky, Weather concealing scene (distant fog) 11/15 Overcast > half of sky, Weather concealing scene 11/16 Overcast > half of sky, No layered haze 11/17 Scattered clouds < half of sky, No layered haze 11/18 Overcast > half of sky, No layered haze
November 2004 Cloud Cover • Large-scale higher clouds appear well simulated • Run 6 makes more large-scale (higher) cloudiness • Low-level cloud/fog events are not • Run 3 makes more low-level (foggy) clouds • Especially on the high bscat days • This will impact aqueous PM chemistry
Wishram Camera November 10, noon Pristine
Run 6 Low High
UW Run 3 Low High
Wishram Camera November 13, noon Pristine
UW Run 3 Run 6 Low Low
August 2004 Meteorology • Wind speed/direction well simulated • Both grids, both MM5 configurations • Run 6 4-km temperatures are highly suspect • Run 6 12-km is better • But min temps too warm during haze period • Better characterization of afternoon mixing? • Run 3 4- & 12-km are better • But too cool during haze period
August 2004 Meteorology • Run 6 4-km humidity too wet • Run 6 12-km humidity better • But not high enough in early morning (related to high min temps) • Run 3 4- & 12-km humidity better • But not high enough in early morning • Overall Run 6 12-km met looks best
November 2004 Meteorology • Wind speed/direction performance appears acceptable • Both grids, both simulations • Run 6 perhaps a bit better (nudging) • Run 6 4-km temperature performance is poor • Run 6 12-km better • Run 3 4-km much better • Run 6 4-km humidity is too low – no fog • Run 6 12-km better • Run 3 4-km much better • Overall Run 3 4-km looks best