The Exceptional Event that triggered the fist regulatory response by EPA was the May 1998 Mexican smoke event. The color images from the NASA SeaWiFS satellite (louched in 1997) allowed the detection and following the evolution of the smoke event.Based on the record smoke impact on the PM10 concentration over the entire Eastern US, the EPA issued a memorandum to the States, as a precursor of the Exceptional Event Rule, promulgated in 2007.------------------Since time immemorial, smoke from forest fires, wind-blown dust storms and other ‘exceptional events’ have punctuated the air quality with extreme concentrations of atmospheric particulates and gases. However, historically the spatio-temporal pattern of air quality during such events was sparse and patchy. This has changed dramatically during the sensing revolution of the 1990s, in particular through the near-real-time availability of color satellite images. Satellites the became the primary sensory inputs for event detection and spatio-temporal characterization. Satellite observations were also responsible for formally including Exceptional Events into the AQ management process. When combined with routine surface-based monitoring data …In the past, the definition and documentation of events has been subjective, dependent on the analyst, the is event type etc.The routine overall characterization of detected events is accomplished by the rich real-time data through delivered through the Analysts ConsolesObjective event definition is now possible through spatio-temporal statistical parameters derivable from routine monitoring dataand their causes is still poorly understood and largely unpredictable.
The spatial distribution of EE flags attributed to Mexican and Canadian fires (left). EE flags attributed to prescribed and wild fires within the US (right). The time series below each map shows the number of flags throughout the country for each day. The spatial distribution of EE flags attributed to African and Asian dust. (left). EE flags attributed to dust origination within the US(right).
NAAPS general description. Species are sulfate, dust, smoke, and sea salt. Aspects impacted by NASA remote sensing products are specification of sources and initialization.Each term in the equation can dominate at one time or another. At a source grid point, S is dominant. One grid point away, advection could be largest. In a cloud R is largest. etc.Image is a composite of geostationary clouds, fires from FLAMBE (pink and yellow dots), and NAAPS aerosol plume forecasts (see legend). It shows 1) production and transport of anthropogenic aerosol in northern latitudes (red), 2) Saharan dust over the Atlantic being scavenged by two tropical cyclones, and 3) smoke from thousands of African fires transported to S. America.
NAAPS initialization benefits from the current 2-D assimilation of aerosol optical depth (AOD) provided by satellite remote sensing (MODIS and MISR) and also 3-D extinction values derived from the CALIPSO CALIOP lidar. The initial conditions are thus improved by assimilating these two parameters.
The August 2012 Western US smoke is a Continental-scale event.While the NAAPS AOT column concentration stretches over much of the continent (>5000 km), the smoke impact on the surface is diminished by about 1000 km. This indicates long distance smoke transport aloft. In fact the PM2.5 concentrations reported in Airnow, do not show smoke impact except near the fires in Idaho.
Exceptional Event Analysis and Decision Support SystemExceptional Events: Past, Present, FutureData, Models, Tools: Decision Support SystemsNRL NAAPS Model: Advancement in Science Rudolf B. Husar Washington University, St. Louis Seminar Presented at Environmental Protection Agency, Research Triangle Park February 5, 2013
Mexican Smoke over the E. U, May 1998 Standard 65 un/m3The day-max ozone is depressed under the smoke plume! Record Smoke Impact on PM Concentrations
Asian Dust Cloud over N. America Asian Dust 100 g/m3 Hourly PM10 On April 27, the dust cloud arrived in North America. Regional average PM10 concentrations increased to 65 g/m3 In Washington State, PM10 concentrations exceeded 100 g/m3
Continental/Hemispheric Dust Events over the US Gobi dust in spring Sahara in summerRegional-scale fine dust events are mainly Fine Dust Events, 1992-2003 - VIEWS ug/m3 fromintercontinental transport
EE Rule Features – RH Perspective• Not rigid but flexible weight of evidence approach • Not based on single FRM measurement• Encourages use of diverse data and models • Satellites, real-time data, emission-transport model etc.• There is a role of science in AQ Management • EE flagging demands science, particularly the ‘but for’ clause
Near-Real-Time Data for May 11, 07 GA Smoke Displayed on DataFed Analysts Console 1 2 3 4 5 6 7 8 9 10 11 12Pane 1,2: MODIS visible satellite images – smoke pattern Console Links May 07, 2007,Pane 3,4: AirNOW PM2.5, Surf. Visibility – PM surface conc. May 08, 2007Pane 5,6: AirNOW Ozone, Surf. Wind – Ozone, transport pattern May 09, 2007 May 10, 2007Pane 7,8: OMI satellite Total, Tropospheric NO2 – NO2 column conc. May 11, 2007Pane 9,10: OMI satellite Aerosol Index, Fire P-xels – Smoke, Fire May 12, 2007 May 13, 2007Pane 11,12: GOCART, NAAPS Models of smoke – Smoke forecast May 14, 2007 May 15, 2007
‘But for’ demonstration: May 2007 Georgia Smoke Red back-trajectories pass through source area
Tropospheric NO2 form May 2008 GA Fire Atlanta Sweat Water fire in S. Georgia Jacksonville Tampa Miami
NO2 form Fires Evidence: OMI Sweat Water fire in S. Georgia (May 2007)
EE Rule Implementation, 2007-2012Exceptional Event Rule in Federal Register in 2007PM2.5 and Ozone EE flags were added to the monitoring dataNext we show the EPA-Approved EE Flags for PM2.5, 2006-2011
Pattern of EE flagged PM2.5 data, 2006-2012Domestic Sources Foreign Sources
Trend of PM2.5 Concentration 2000-2003 avg. 2009-2012 avg. >35 ug/m3 station countA reason for the 2006-2010 EE flag decline is the As a result of PM2.5 decline, the number ofoverall reduction in PM2.5 concentrations. >35ug/m3 samples has also declined dramatically. No NAAQS exceedances-no EE flag.
Regional Haze Rule: Natural AerosolThe goal is to attain natural conditions by 2064;Baseline during 2000-2004, first Natural Cond. SIP in 2008;SIP & Natural Condition Revisions every 10 yrs
PM2.5 EE Flag Decline Expected Increase in 2012 Drought Anomaly, 2012Trend of EE flags for PM2.5between 2006 and 2012 However, in 2012 the average AOT from smokebased on the official EPA AQS database. The EE was higher than any year between 2006 andflags declined tenfold between 2007-8 and 2010-11 2012, probably due the severe drought. The EE flags for 2012 are expected to rise again in 2012.
Smoke Super-Events in 2012: June 20- July 10 August 1- August 20 20 Average Smoke Emission Rate Average Smoke Optical DepthAverage Smoke Surface Concentration
O3 ‘Violation’ TrendsNumber of CONUS Stations with O3>75 ppb 1993-2013 2010-2013 Apr-Oct 2012
Exceptional EventDecision Support System (EE DSS) NASA Grant: 2009-2012 NASA and NAAPS Products for Air Quality Decision Making, D. Westphal, PI, R. Husar, CoI Washington University, McDonald Academy for Global Energy and Environmental Partnership (MAGEEP) EE_CATT Screencast
October 2012 MT-KS Dust Event 121015_Montana_Dust Event
October 2012 Dust Event: Passage of the dust plume
Oklahoma Dust Plume Event over Huntsville, Alabama October 19, 2012 NSSTC Rooftop Camera, Looking East, without and with DustKevin Knupp, Michael Newchurch, Udaysankar Nair, Dustin Phillips, David Bowdle, Shih Kuang, Wesley Cantrel, University of Alabama in Huntsville Kathy Jones Chattanooga-Hamilton County Air Pollution Control Bureau Claire Aiello WHNT TV, Huntsville, Alabama Atmospheric Science Brown Bag Mini-Seminar, October 23, 2012
Oklahoma Dust Plume Event over Huntsville, Alabama, October 19, 2012 Monte Sano WHNT TV photographs (Jacks Camera Network, WHNT) Donegal Drive, looking west (Megan Hayes, WHNT) Monte Sano (Rebekah Bynum) Colbert Heights Mountain Fort Payne (Kim Pendergrass)Looking East, (Carter Watkins) Lake Guntersville
Oklahoma Dust Plume Event over Huntsville, Alabama, October 19, 2012 Altitude in km, time in Coordinated Universal Time (CDT = UTC - 05:00), intensity in false color Peak at ~17 UTC (12 N EDT)Time-Height Cross-Section of Relative Signal Intensity from Vertically Viewing Ceilometer Mobile Integrated Profiling System (MIPS), University of Alabama in Huntsville http://vortex.nsstc.uah.edu/mips/data/current/ceilometer/
EE DSS Tools: Data System Architecture• Data are accessible from the Air Quality Data Network (ADN) by the AQ Community Catalog• ADN is facilitated by the GEO AQ Community of Practice (GEO AQ CoP), including R. Husar’s group.• The generic client tools (red boxes) are for processing and visualization; used in many applications• Specialized Application Tools are dedicated to specific applications, e.g. event detection
Navy Aerosol Analysis and Prediction System NAAPS by D. Westphal et al, NRL Why I luv NAAPS:1. Assimilates satellite aerosol optical thickness and fire pixels2. Provides 4D aerosol structure for dust, smoke, sulfate, sea salt3. Open access to 10 years of global simulations (via DataFed)
D. Westphal Navy Aerosol Analysis and Prediction SystemSeptember 11, 2011Key:Smoke = blueDust = greenSulfate = red
NASA Data for NAAPS Initialization Multiple aerosol sensors are critical for assimilation.Forecasting is an initial value problem:Requires the 3-D distribution of aerosol concentration at the start of the forecast:: Assimilation of previous forecast + information from remote sensing of aerosolsCurrent capabilities: Aerosol Optical Depth (AOD; 2-D) (MODIS and MISR) Extinction (3-D) (CALIPSO) Natural run + Ocean MODIS + Land/Ocean MODIS + land/Ocean MISR + Land/Ocean MISR
Aerosol Optical Thickness – Aeronet The Gold Standard for Satellite Calibration
AERONET Sun photometer – MODIS AOD Comparison Very low bias except in blue sites Kanpur, IN http://webapps.datafed.net/datafed.aspx?page=Aeronet/Aeronet_MODIS/AOT_MODIS_Aeronet_Bias
VIEWS Sulfate – NAAPS Sulfate SO4 BIASOBSERVATION MODEL
Goal: ‘Reconciliation’, ‘Harmonization’…’Closure’By iterative refinement of of Emissions, Observations and Models HTAP, 2010Reconciling emissions, observations and models (EOMs), has been elusiveEOMs are generally autonomous and quite separate activitiesSoftware tools are available to support EOM reconciliationBut closing the EOM loop requires “interoperability” of people and machines
4D Dust, Smoke, Sulfate Vertical Cross Section ViewsVertical dust cross sections at about 120 (surface plume) and 1000 km (elevated plume).Knowing the vertical structure of smoke and dust plumes is critical to EE documentationThe DataFed Browser now incorporates vertical cross section views
Long-Term Model Data 2006-Now Emission Surface Conc. Vertical AOTA significant fraction of the dust vertical column is in the troposphere and it is ‘global’Most of surface dust is local and highly variable in space and time
Satellite-Surface PM relationshipThe NAAPS helps separating local and ‘global’ dust but much work is needed
EPA PM2.5 – CMAQ Model PM2.5 Summer PM2.5 BIASOBSERVATION MODEL
EPA PM2.5 – CMAQ Model PM2.5 Bias Winter PM2.5 BIASOBSERVATION MODEL
EPA PM2.5 – CMAQ Model PM2.5 Bias Winter DJF MAM JJA SON Nitrate Organics Fine Dust Bio. Organics Low in DJF Low in DJF Low in MAM High MAM & JJA Add nitrate source Improved smoke by Add Sahara, local dust Reduce biogenic OCInverse modeling of combined Dust and smoke BC for Adjust source trem VIEWS Nitrate chemical, satellite, spa CMAQ – e.g. NAAPS ce-timeVIEWS NO3 DJF CMAQ NAAPS Dust, July Tool to Iteratively Reduce the Bias Actual closure to be worked out by the AQ community
Many Thanks:• Kari Hoijarvi• Erin Robinson• Rich Poirot• Doug Westphal• Neil Frank