MPCA Forecasting Summary 2010 Jessica Johnson, Patrick Zahn, Natalie Shell Sonoma Technology, Inc. Petaluma, CA Presented to Minnesota Pollution Control Agency St. Paul, MN June 3, 2010 aq-ppt2-01 907021-3880
Outline About STI Services provided to MPCA Daily forecasting operations Forecasting philosophy Air quality summary for winter 2009 2010 Meteorology overview for 2009 2010 El Niño Storm track Influence of meteorology on air quality Summary 2
About STI Sonoma Technology, Inc. (STI) provides science- and technology-based solutions for clients air quality and meteorological needs worldwide. Founded in 1982 Located in Petaluma, California 63 employees Employee-owned and directed 15 meteorologists 2 AMS Certified Consulting Meteorologists (CCMs) Petaluma San Francisco San Jose San Francisco Bay Area 3
Services Provided to MPCA Issue daily forecasts Same-day, next-day, and extended daily forecasts Daily PM 2.5 forecasts provided year-round; daily ozone forecasts provided from May 1 September 30 Dissemination of forecasts Email Website (SmogWatch.com) AIRNow submittal and EnviroFlash Daily AQI summary Consultation Analysis of air quality events Agency-directed media contact 4
Daily Forecast Operations Eight steps to produce an air quality forecast 1. Review yesterday s forecast 2. Review latest air quality data 3. Review weather systems 4. Run forecast tools 5. Develop conceptual forecast 6. Produce final forecast 7. Distribute forecast 8. Monitor AQ and meteorology 5
Forecasting Philosophy (1 of 2) Meteorology key processes Dispersion (horizontal mixing) Vertical mixing Transport Sunlight Temperature Variations due to Weather patterns Geography Diurnal Seasonal 6
Forecasting Philosophy (2 of 2) Forecasting process Predict weather Predict effect of weather on emissions and chemistry Estimate AQ concentration Convert to AQI Ozone Clouds = reduced sunlight Slows photochemistry O 3 =40 ppb Good AQI 7
Air Quality Summary for Winter 2009 2010 (1 of 2) Air quality during winter 2009 2010 was worse than the 7-year average and significantly worse than the 2008 2009 winter season. Analysis period is November 1, 2009 March 8, 2010 8
Air Quality Summary for Winter 2009 2010 (2 of 2) Multiple episodes occurred, during which AQI levels reached Advisory or Alert criteria 1 AQI levels exceeded 90 on 15% of days 1 AQI levels of 90-100 constitute an Air Quality Advisory. AQI levels of 101 and above constitute an Air Quality Alert. 9
Meteorology Overview (1 of 5) The 2009 2010 winter was warmer than average, and precipitation was near average. NOAA Earth System Research Laboratory, U.S. Climate Division Data Set Mapping Page (http://www.esrl.noaa.gov/psd/data/usclimdivs/) 10
Meteorology Overview (2 of 5) The weather this year was driven by a moderate to strong El Niño pattern. El Niño is a climate pattern driven by unusually warm water in the eastern equatorial Pacific Ocean. NWS Climate Prediction Center (http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/sstanim.shtml) 11
Meteorology Overview (3 of 5) El Niño s effects are felt worldwide. Ocean temperature patterns affect weather far from the equatorial Pacific. National Oceanic and Atmospheric Administration s (NOAA) National Climatic Data Center (http://www.ncdc.noaa.gov/paleo/ctl/images/warm.gif) 12
Meteorology Overview (4 of 5) El Niño s affect the weather in the upper Midwest The Pacific Jet Stream (strong winds at about 30,000 ft) is pushed farther south than usual. Storm systems generally follow the jet stream. NOAA s Climate Prediction Center (http://www.cpc.noaa.gov/products/analysis_monitoring/ensocycle/nawinter.shtml) 13
Meteorology Overview (5 of 5) Observed storm tracks for 2008 2009 and 2009 2010 A more southerly storm track in 2009 2010 sent additional storms through the southern plains and across the Southeast rather than through the Midwest. 2008-2009 2009-2010 Adapted from the NOAA Earth System Research Laboratory Physical Sciences Division (http://www.esrl.noaa.gov/psd/cgi-bin/data/composites/printpage.pl) 14
Influence of Meteorological Conditions on Air Quality for Winter 2009 2010 (1 of 5) 1. Southerly winds ahead of storm systems over the plains brought moisture and pollutants into Minneapolis-St. Paul, enhancing particle production. On March 6, 2010, particle levels in the Twin Cities reached 31.2 μg/m 3. Adapted from NOAA Daily Weather Maps (http://www.hpc.ncep.noaa.gov/dailywxmap/) 15
Influence of Meteorological Conditions on Air Quality for Winter 2009 2010 (2 of 5) 2. High relative humidity associated with persistent mist and light rain/snow enhanced particle production. These weather conditions were associated with low-pressure systems passing to the south. 3. Atmospheric stability also contributed to the formation of fog, which further aided particle formation. Wikimedia commons (http://commons.wikimedia.org/wiki/file:minneapolis_fog.jpg) St. Paul Hazecam (http://www.mwhazecam.net/stpaul.html) 16
Influence of Meteorological Conditions on Air Quality for Winter 2009 2010 (3 of 5) 4. Storms passing to the south did not provide a sufficient clean-out : March 4-8, 2010. March 4, 5, 6, 7, 8, 2010 NOAA Daily Weather Maps http://www.hpc.ncep.noaa.gov/dailywxmap/ AIRNow (http://www.airnow.gov) 17
Influence of Meteorological Conditions on Air Quality for Winter 2009 2010 (4 of 5) Storms passing to the south did not provide a sufficient clean-out (continued) Winds were lighter than winds in 2008 2009 Data from AIRNow-Tech (http://www.airnowtech.org) 18
Influence of Meteorological Conditions on Air Quality for Winter 2009 2010 (5 of 5) By contrast, a system passing through northern Minnesota brings clean air to the region as it departs: January 12-15, 2010. January 12, 13, 14, 15, 2010 NOAA Daily Weather Maps http://www.hpc.ncep.noaa.gov/dailywxmap/ AIRNow (http://www.airnow.gov) 19
Summary (1 of 2) Winter 2009 2010 was more polluted than previous years due to meteorological conditions. A strong El Niño pattern resulted in low-pressure systems passing farther south of Minnesota than normal. These systems resulted in: Winds that brought pollutants from the South into the Twin Cities. Moisture that helped form mist, fog, and light rain or snow, potentially enhancing particle production. Reduced frequency of clean-out events. 20
Summary (2 of 2) A relatively stable atmosphere also helped fog to form and limited vertical mixing, trapping pollutants at ground level. Long-range predictions of El Niño behavior in the future may help guide the seasonal air quality outlook for the Twin Cities. 21
Questions? Contact: Jessica Johnson Sonoma Technology, Inc. Phone: (707) 665-9900 Email: jjohnson@sonomatech.com 22