New Generation Aerosol Satellite Products for Air Quality Mapping and Analysis Amy K. Huff Penn State University 2017 MARAMA Air Quality Monitoring Training Workshop November 3, 2017
Satellites Identify Aerosols in the Atmosphere VIIRS RGB and FRP Oct 9, 2017 N. CA Wildfires 2
Growing Importance of Wildfire Smoke on Ambient Air Quality in the Mid-Atlantic 34.7 µg/m 3 PHL 31.6 µg/m 3 Delaware 37.5 µg/m 3 Susq. Valley 36.2 µg/m 3 BAL Highest observed O 3, with most widespread exceedances, now occur on days impacted by smoke from upwind wildfires Western U.S. Alaska Canada Mexico/C. America Also affects PM 2.5, notably Nov 2016 Southeastern U.S. 3
Difficult to Predict Impacts of Transported Smoke Smoke from major wildfires can be transported long distances, sometimes 100s of km downwind Smoke is an issue for air quality because it contains precursors for O 3 and PM 2.5 production (NO x and VOCs) and primary PM 2.5 Most of our forecast tools are not skillful for predicting impacts of transported smoke NAQFC O 3 and PM 2.5 models: currently don t include transported smoke from outside CONUS in boundary conditions Satellite aerosol products help to track transport of smoke plumes and to predict whether smoke will mix to surface 4
NAQFC Numerical Model Under-Predicts on the Worst O 3 Days (Influenced by Smoke) Philadelphia metro area 2014-2016 NAQFC Prediction (ppbv) Red bar demarcates observed 8-hr average O 3 80 ppbv ( worst O 3 days) in Philadelphia, 2014-2016 - Impacted by smoke - Routinely under-predicted by NAQFC Forecasters need another tool to help identify days when smoke will affect O 3 (and PM 2.5 ) forecasts: - Aerosol satellite products
Aerosol Optical Depth (AOD) Oct 9, 2017 Quantitative indicator of aerosols Also called AOT Measure of scattering and absorption of visible light by aerosols Unitless; values typically range from 0 to 1 in the U.S. Higher values (red, orange, yellow colors) correspond to higher aerosol concentrations Clouds block measurement, so there is no AOD in white cloud-covered areas 6
New Aerosol Optical Depth Algorithm New Enterprise Processing System (EPS) algorithm: replaces current Interface Data Processing Segment (IDPS) algorithm Retrieval over bright land, extended reporting range [-0.05-5.0], extensive internal tests Separate algorithms for land and water IDPS (previous) seasonal mean AOT Band Central Retrieval Internal Test Wavelength (µm) Land Water Land Water M1 0.412 X X X M2 0.445 X X X M3 0.488 X X X M4 0.555 X X X M5 0.672 X X X X M6 0.746 X M7 0.865 X X X M8 1.240 X X M9 1.378 X X M10 1.610 X X M11 2.250 X X X X M15 10.763 X X M16 12.013 X EPS (new) seasonal mean AOT 7
Aerosol Detection (Smoke Mask) Oct 9, 2017 Qualitative indicator of smoke aerosols Derived using satellite measurements in visible and IR Use smoke mask to identify local and transported smoke plumes Colored shades of pink Light pink: thin smoke Bright pink/magenta: thick smoke 8
True Color Imagery Complements AOD Northern California wildfires, Oct 9, 2017 True Color Imagery showing grey smoke plumes AOD high AOD corresponds to smoke 9
Satellite Data are Not Surface Measurements Satellite products are measurements in a column of the atmosphere, from the surface to the top of the atmosphere Satellites do not measure smoke or AOD or PM 2.5 directly at the surface Often satellites will indicate areas of smoke that are aloft in the atmosphere But numerous research studies have established a relationship between satellite AOD and surface PM 2.5 concentrations 10
AOD-Derived Estimated Surface PM 2.5 Aug 19, 2015 AOD can be used to estimate surface PM 2.5 concentrations using predefined regression relations derived from model simulations Current best method based on older generation AOD (from MODIS) using older algorithm NOAA currently working to update relationships for new EPS algorithm and new generation satellite data van Donkelaar, A., R. V. Martin, M. Brauer, R. Kahn, R. Levy, C. Verduzco, and P. J. Villeneuve, Global estimates of ambient fine particulate matter concentrations from satellite-based aerosol optical depth: Development and application, Environ. Health Perspec., doi:10.1289/ehp.0901623, 2010. 11
AOD-Based Forward Aerosol Trajectories Smoke transport from Ft McMurray fire May 6-7, 2016 Magenta/pink lines indicate transport of smoke south into U.S., remaining near surface Trajectories give idea of transport of aerosol plumes Areas of high AOD (>0.4) used as starting locations Trajectories initialized at 50, 100, 150, and 200 mb above surface Trajectories run using NAM 12Z run output: Pink: near surface White: away from surface 850 mb wind vectors (white) 3-hr accumulated precipitation (yellow) 12
Smoke Transported to Northern Plains, May 7 Smoke from Ft McMurray fire traveled to N. Plains states and caused widespread exceedances of PM 2.5 NAAQS on May 7 Event only lasted one day PM 2.5 dropped to Code Yellow on May 8 13
NAQFC PM 2.5 Numerical Model Did Not Predict Smoke Impacts µg/m 3 14
New Generation Satellite Products JPSS: polar-orbiting satellites - Low Earth orbit (~825 km above surface) - Global coverage - Only 1-2 measurements per day - Provide 85% of data used in numerical weather prediction GOES-R series: geostationary satellites - High-altitude orbit (~35,800 km) - Orbital speed of satellite matches rotation speed of Earth, so coverage limited to specific (constant) location - Nearly continuous measurements - Meteorological satellites, used to monitor severe storm development, natural hazards 15
Joint Polar Satellite Series (JPSS) Orbit Earth 14 times/day, pole to pole Image entire globe 2 times/day Global coverage! SNPP launched Oct 2011 JPSS-1 (NOAA-20) scheduled to launch on Nov 10, 2017 Orbit 50 min ahead of SNPP Follow-on to NASA suite of earth-observing satellites: Terra, Aqua, and Aura Research applications, also input to NWP 16
VIIRS: Key Instrument for Aerosol Measurements Visible Infrared Imaging Radiometer Suite (VIIRS) is one of 5 instruments on SNPP VIIRS has 22 spectral bands with high spatial resolution (750 m) Follow-on to MODIS on Terra and Aqua satellites Afternoon overpass time, so observations made ~1:30 PM local time (1 day temporal resolution for aerosol products) So today s near-real time VIIRS observations are available in the mid-afternoon, typically ~2-3 hours after overpass Limited usefulness for forecasting Very useful for post-analysis 17
Advantages of VIIRS (New Generation JPSS) VIIRS has higher spatial resolution aerosol products (750 m) vs. MODIS (3 km) Able to resolve smaller aerosol features, like smoke plumes VIIRS has wider swath (3000 km) vs. MODIS (2330 km) No gaps in coverage! Higher spatial resolution at swath edges MODIS AOD 3 km VIIRS AOD 750 m MODIS VIIRS 18
Successful O 3 Exceptional Event Exemption Using Satellite Data CT Dept of Energy and Environmental Protection (Michael Geigert) recently received a concurrence from EPA Region 1 for their Exceptional Event demonstration of the May 25-26, 2016 O 3 event O 3 exceedances at 4 CT monitors Smoke from Ft McMurray fire in AL, Canada Satellite images and data were a valuable part of the exceptional events demonstration VIIRS AOD-based forward aerosol trajectories VIIRS AOD-derived estimated surface PM 2.5 concentrations 19
Geostationary Operational Environmental Satellites R-Series (GOES-R) Revolutionary new geostationary satellites Like going from B&W TV to HD GOES-16 launched Nov 19, 2016 (GOES-East) GOES-S scheduled launch March 2018 (GOES-West) GOES-16 currently in check-out orbit at 89 W NOT operational! Transition and drift to 75 W: Nov 30 to Dec 20 No GOES-16 data during transition (instruments in safe mode) GOES-16 will officially become GOES-East ~Dec 20 20
ABI: New Generation GOES Imager Advanced Baseline Imager (ABI) is one of 6 instruments on GOES-R series satellites Huge leap forward in technology on geo satellite ABI has 16 spectral bands vs. 5 on current GOES imager New products! Higher spatial resolution and accuracy (closer to VIIRS)! Faster scan rate compared to current GOES imager More frequent observations! GOES-16 not yet operational ABI products still β- and provisional maturity 21
ABI Scan Mode 3 ( Flex Mode ) Current imager: 26 min full disk 7 min CONUS 22
Advantages of ABI (New Generation GOES) Higher spatial resolution products (1-2 km vs. 4 km) Higher accuracy aerosol products (multi-channel retrieval) New products! (RBGs, aerosol detection) More frequent observations Routine CONUS, full disk views ABI 2 km, 15 min Current Imager 4 km, 30 min 23
NOAA Aerosol Initiatives NOAA wants their aerosol products to be useful for operational users Air Quality Proving Ground (AQPG) Fire and Smoke Initiative Aerosol product developers work directly with users to test products, obtain feedback, improve products NWS incident meteorologists (IMETs) U.S. Forest Service State/local air quality forecasters NRT websites developed so operational users can access aerosol imagery outside of AWIPS 24
Zoom in/out eidea: NRT VIIRS (JPSS) Aerosol Products http://www.star.nesdis.noaa.gov/smcd/spb/aq/eidea/ calendar to select date of interest animations and external links main product overlay buttons 25
AerosolWatch: NRT ABI (GOES-16) Aerosol Products https://www.star.nesdis.noaa.gov/smcd/spb/aq/aerosolwatch/ CONUS or Full Disk view Zoom in/out Open archive; Time Stamp Animation controls Select ABI Layer Overlay state and national labels Default is today, CONUS view, synthetic RGB 26
May 17-18, 2017 Smoke-Impacted O 3 Event Regional high O 3 event along the I-95 Corridor (Mid-Atlantic and southern New England) Driven by sunny, hot weather and transport of smoky air mass from Mexico/Central America Forecasters (e.g., PHL/DE, CT) used VIIRS AOD to help verify extent of smoky air transport 27
NOAA HMS Fire and Smoke Analysis for May 16 HMS is not a NRT product - Great for postanalysis - Less useful for forecasting 28
VIIRS AOT for May 16 Showing Smoke High resolution VIIRS AOD picks up on smoke But NRT imagery cuts off north and east of fires NRT VIIRS imagery not available until after forecast deadline of ~2:45 PM 29
AOD-Based Forward Aerosol Trajectories 48-hour aerosol trajectories initialized on May 16 with VIIRS AOD shows transport of smoke from the eastern coast of Mexico northeastward toward Mid- Atlantic and New England 30
ABI Full Disk Synthetic RGB for May 16 We need aerosol products from ABI! Hi-resolution 20 min latency Ideal for forecasting Hard to see smoke plumes along Gulf Coast using this preliminary RGB data from ABI AOD from ABI was not available at this time (not validated) But we will have it next year!! 31
At a Glance: NRT Aerosol Products Data Characteristic ABI VIIRS Orbit Geostationary Polar-orbiting Observation Time Continuous during daylight ~1:30 PM Data Coverage Centered on 75 W Global Temporal Resolution Latency Spatial Resolution RGB AOD Product Status (Nov 2017) 5 min (CONUS view) 20 min (on AerosolWatch) 1 km (synthetic RGB, CONUS view) 2 km (CONUS view) RGBs: provisional Aerosol: β-maturity 1 per day 2-3 hours (on eidea) 750 m 750 m Fully validated 32
New Generation Aerosol Satellite Products New, high accuracy, high resolution products for: Forecasting (GOES-16 ABI) Verification/post-analysis (JPSS VIIRS) Exceptional event demonstrations Transported smoke becoming greater issue for O 3 and PM 2.5 air quality locally in the Mid-Atlantic ABI aerosol products have great potential for helping forecasters track smoke in operational setting New AerosolWatch website for NRT ABI imagery GOES-16 ABI aerosol products will be provisional in Jan 2018 and fully validated by Sept 2018 Additional geostationary air pollution satellites coming soon! TEMPO (2019-2021), GEO-CAPE (2021?) 33
Acknowledgements Shobha Kondragunta, NOAA NESDIS/STAR Hai Zhang, IMSG at NOAA NESDIS/STAR and the entire NOAA aerosol Cal/Val team NOAA JPSS and GOES-R programs Air Quality Proving Ground Fire and Smoke Initiative 34