The Regional Atmospheric Measurement Modeling and Prediction Program (RAMMPP) Russell Dickerson & Jeff Stehr CICS September 8, 2010 Image taken from URF Aztec Aircraft. B. Taubman, B. Doddridge

2 Problem The eastern US suffers from unsafe levels of ozone (photochemical smog) and fine particulate matter (haze). Background The retrieval of AOD from the GOES EAST Aerosol/Smoke Product (GASP) measurements is sensitive to aerosol optical properties such as SSA and surface reflectance. GASP is useful for forecasting PM2.5 (haze) and evaluating models such as CMAQ and WRF-Chem.

33 (Regional Atmospheric Measurement Modeling & Prediction Program) (Regional Atmospheric Measurement Modeling & Prediction Program) Balanced Theory & Observations Observations Surface: Shenandoah National Park, VA Beltsville, MD Greenbelt, MD Piney Run, MD Aloft Cessna 402B Aircraft Profiler Sondes Remote (NASA) OMI/TES etc. MOPITT (CO) MODIS (particles) SCIAMACHY (SO 2, NO 2, H 2 CO … ) Input Emissions Inventories Emissions Models (Chem Engineering) MM5/WRF Dynamical Model 0.5 to 4-km Resolution Forecasting Chem/Trans Models CMAQ Modular Open Code Collaborative w/EPA or WRF-CHEM Regional Linked met/chem GOCART global

4 Major discoveries from RAMMPP 1. Tropospheric aerosols accelerate ozone (smog) production. 2. The spatial and temporal scale of ozone events are larger and longer than thought because: The boundary layer is vented faster than WRF predicts. Reservoir species sequester and re-release NOx. NOx reductions are more effective than expected. Emissions inventories are too high for NOx. 3. Particles become fewer, larger, and darker above the PBL.

5 CASTNET & NADP Sites in Beltsville, MD

6 MDE/Howard University Beltsville Site

77 Aztec-F Research Aircraft GPS Position (°Lat, °Long) Meteorology (T, RH, Pr, P alt, WS, WD) Carbon Monoxide (CO) Ozone (O 3 ) Sulfur Dioxide (SO 2 ) Aerosol Optical Properties: Absorption, b ap (565 nm) Scattering, b scat (450,550,700 nm) Aerosol Particle Size (MetOne) 6 cuts – Range µm

8 The new Cessna 402B allows more accurate measurement of aerosol optical properties and chemical composition as well as additional instruments for NO 2 and VOC’s.

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10 General Study Area & Spiral Locations Summer observations over eastern North America General subsidence (Bermuda High) Cloud pumping through fair weather cumulus. Aircraft and satellite observations.

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Black Carbon or Soot Soot Also called black carbon or elemental carbon. Absorbs solar radiation and warms climate. Carcinogenic. The ambient EC concentration decreases ~50% in the recent 11 years.

13 Percent density Typical westerly West-southwest Westerly AOD ~0.2 WSW AOD ~ 0.4 o Top 0.3% SO 2 sources

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18 Conclusions 1.RAMMPP has generated a long history (up to 17 yr) of trace gas and aerosol properties over the eastern US. 2.Air quality is improving, but still above safe levels for human health and welfare. 3.The Mid-Atlantic region is a good test bed for NOAA’s air quality forecasts and satellite aerosol detection. 4.We will use surface observations and aircraft profiles to evaluate and improve the retrievals from GASP and expand our understanding of atmospheric chemistry and climate.

19 Background The retrieval of AOD from GASP measurements is sensitive to SSA and surface reflectance. GASP is useful for forecasting PM2.5 (haze) and evaluating models such as CMAQ and WRF-Chem. Testable Hypotheses 1. Black carbon (light-absorbing aerosols) contribute substantially to atmospheric heating over the eastern US. 2. The SSA of aerosols decreases above the PBL because BC has a longer lifetime than sulfates. 3. The SSA of aerosols increases in the summer because sulfate and OA increase while BC emissions remain constant. 4. The absorption efficiency of soot increases with higher concentrations of sulfate and transparent organic material because of coating of soot particles.

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