Updated PM 2.5 and O 3 CART Analyses for Detroit,

Changes to previous analysis PM 2.5 : One year (2010) of PM 2.5 and met data were added to the previous dataset ( ) and model was rerun for Ozone: Two years (2009, 2010) of O 3 and met data were added to previous dataset ( ) and model was rerun for

Meteorological variables included These variables were selected from previous model runs that had many more variables included; these are just those that had any influence in previous models: – Daily precipitation – Cloud cover – 850 and 700 mb temperatures at 6 am – Maximum daily temperature, dew point, relative humidity, pressure – Average daily wind speed – Average daily, morning, and afternoon wind direction as N/S and E/W vectors – Morning, afternoon and evening dewpoint and pressure – Day of week – Previous day’s average temperature, pressure, wind speed, wind direction – Change in temperature and pressure from previous day – 2- and 3-day average wind speed and temperature

PM 2.5

Trends in high-PM nodes

Ozone

Trends in high-O 3 nodes

VariableScore DP_EVE100.00|||||||||||||||||||||||||||||||||||||||||| MEAN_S_WN81.23||||||||||||||||||||||||||||||||| WS3DAY72.88|||||||||||||||||||||||||||||| WS2DAY70.78||||||||||||||||||||||||||||| S_WN_AM58.66|||||||||||||||||||||||| PRESSCHANGE57.73|||||||||||||||||||||||| LAGWS52.44|||||||||||||||||||||| LAG_S_WN51.26||||||||||||||||||||| TEMPCHANGE50.67||||||||||||||||||||| MEANWS39.51|||||||||||||||| DP_PM32.42||||||||||||| LAGMEANPRESS24.31||||||||| DP_AM17.24|||||| PRESS_EARLYAM15.86|||||| MAXTEMP14.39||||| TEM2DAY13.81||||| PRESS_AM11.36|||| MAXDP10.46||| MAXRH9.49||| DP_EARLYAM6.71|| TEM3DAY6.04|| MAXPRESS5.73| LAGMEANTEMP4.37| PRESS_PM3.72| W_WN_PM2.29 W_WN_AM0.13 Ranking of Influential Variables VariableScore MAXTEMP100.00|||||||||||||||||||||||||||||||||||||||||| TEM2DAY50.61||||||||||||||||||||| AM850TEMP43.61|||||||||||||||||| TEM3DAY37.60||||||||||||||| MAXDP29.81|||||||||||| LAGMEANTEMP26.78||||||||||| TEMPCHANGE16.40|||||| WS2DAY15.06||||| WS3DAY7.52|| LAGWS7.24|| MEANWS6.93|| MAXRH4.39| MEAN_S_WN4.35| MEAN_W_WN3.85| LAGMEANPRESS3.80| DP_AM2.49 DP_EARLYAM2.46 DP_PM1.67 LAG_W_WN1.21 LAG_S_WN0.57 S_WN_AM0.24 AM700TEMP0.22 PRESS_AM0.09 PM 2.5 Ozone

Findings PM 2.5 and ozone models mostly unchanged with the addition of 2010 data Most important met variables are…. PM 2.5 : southerly wind direction (current and previous day) and extended 2- and 3-day periods of slow wind speeds, followed by high humidity, dew point, temperature, and pressure Ozone: daily maximum temperature, temperature aloft, 2- and 3-day temperature, relative humidity, and 2- and 3-day wind speeds Trends for high concentration nodes are … PM 2.5 : significantly downward Ozone: slightly to moderately downward