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Monitoring Needs & Issues

Monitoring Needs & Issues. Bill Malm National Park Service May 15, 2008. What modifications in the national monitoring networks are required to assess effects and apportion the many and varied chemical species to their many and varied emission sources?. NEEDS. Assessments Ecosystem health

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Monitoring Needs & Issues

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  1. Monitoring Needs & Issues Bill Malm National Park Service May 15, 2008

  2. What modifications in the national monitoring networks are required to assess effects and apportion the many and varied chemical species to their many and varied emission sources?

  3. NEEDS • Assessments • Ecosystem health • Total deposition estimates (wet and dry) of all sulfur and reactive nitrogen species – • Critical loads • Visibility • Health (other) • Attribution of each species to its emission source (control measures)

  4. Issues • Time scale of sample collection. • 1 week deposition monitoring • Every third day for IMPROVE/STN • Semi-continuous? • Accuracy with which some species are measured • Some key species are not measured at all

  5. What is reactive nitrogen? • The term reactive nitrogen includes all biologically active, photochemically reactive, and radiatively active nitrogen compounds in the atmosphere and biosphere of the earth. (both reduced and oxidized forms)

  6. NADP 2004 Annual Summary Wet deposition patterns and trends • N deposition “hot spot” in northern Colorado Rockies • Current N deposition ~ 20x natural levels • Nitrogen deposition increasing at high elevation sites • Ammonium deposition increasing faster than nitrate Niwot Saddle NADP site Burns (2003)

  7. Are Fires Contributing to the Increasing Wet Nitrogen Deposition? Wet nitrate concentration deposition trends Wet ammonium concentration deposition trends

  8. ROcky Mountain Atmospheric Nitrogen and Sulfur study (ROMANS) STATEMENT OF THE PROBLEM • Rocky Mountain National Park (ROMO) is experiencing a number of deleterious effects due to atmospheric nitrogen and sulfur compounds. These effects include visibility degradation, changes in ecosystem function and surface water chemistry from atmospheric deposition, and human health concerns due to elevated ozone concentrations. • The nitrogen compounds include both oxidized and reduced nitrogen. Emissions of nitrogen compounds need to be reduced to alleviate these deleterious effects. Various regulatory programs are underway to address emission reductions, many of which will be achieved from the most easily identified contributors to oxidized nitrogen related effects at the park.

  9. Concerns about increasing reactive nitrogen in Rocky Mountain National Park (Typical of all high mountainous regions) • Increased haze reducing visibility • Low capacity to sequester atmospheric N deposition • N enrichment and shifts in diatom communities in alpine lakes • N enrichment in organic soil layer and Engelmann spruce needles on eastern slope

  10. Why Ammonia? • Direct ecosystem effects • Response of a basic gas neutralizing acidity in particles and gases. (neutralization of acidic sulfate aerosols – reaction with nitric acid vapor – reactions with organic salts) • Response of PM formation can be dislocated from where ammonia reduction first took place. • Ammonia deposition via cloud uptake and subsequent rain, dry deposition in the gas vs particle phase have vastly different time scales that leads to different lifetimes and particle response.

  11. The urban/industrial-agricultural interface ??? Organic nitrogen? +hv HNO3 + NH3  NH4NO3(p) NOx VOC

  12. ROMANS OBJECTIVES • Characterize the atmospheric concentrations of sulfur and nitrogen species in gaseous, particulate and aqueous phases (precipitation and clouds) along the east and west sides of the Continental Divide (Organic Nitrogen?) • GAS: NH3, R-NH2, NOX(NO+NO2), NOY(HNO3, PAN, etc) • PARTICLE: NH4, NO3,ORGANICS (reduced and oxidized)? • WET (rain and clouds): NH4, NO3, ORGANICS (reduced and oxidized)? • Identify the relative contributions to atmospheric sulfur and nitrogen species in RMNP from within and outside of the state of Colorado. • Identify the relative contributions to atmospheric sulfur and nitrogen species in RMNP from emission sources along the Colorado Front Range versus other areas within Colorado. • Identify the relative contributions to atmospheric sulfur and nitrogen species from mobile sources, agricultural activities, large and small point sources within the state of Colorado.

  13. RoMANS measurement network • Two measurement campaigns • Mar/Apr 2006 • July/Aug 2006 • Spring and summer historically have highest deposition fluxes • 4 site types • Continuous to weekly monitoring

  14. Spring overview • Concentrations lower in mountains • Gases dominate at eastern and western sites • Highest ammonia at Brush in NE Colorado • Particles dominate in mountains

  15. Summer overview • Concentrations higher than in spring • Highest concentrations again east of RMNP • Increasing N gas importance in mountains

  16. SOME PRELIMINARY RESULTS • Total N deposition was about twice (2) as high during the summer vs spring. • About 45% of N deposition is not being measured in the current monitoring programs (NAPD & CASTNET). • Deposition of N is about 2/3 wet (rain and snow) and 1/3 dry (particles and gases). • Organic N may be about 30% of total deposition and is notcurrently being measured.

  17. MONITORING NETWORKS • IMPROVE • STN • CASTNET • NADP/AIRMON • MERCURY • NAAQS • Persistent Organic Pollutants(POPs) • Others?

  18. IMPROVE (24 hr every third day) • Dry Species (Current) • SO4 • NO3 • Total POM • Metals (soil and attribution) • Dry Species (Missing) • NH3/NH4 • Reduced and oxidized organic nitrogen containing particulates • NOx (NO and NO2) • Oxidized organic gases (PAN - alkyl nitrates …) • Reduced organic gases (Aliphatic amines …..)

  19. CASTNET (weekly) • Dry Species (Current) • SO2/SO4 • HNO3/NO3 • NH4 • Dry Species (Missing) • NH3 • NOx (NO and NO2) • Oxidized organic gases (PAN - alkyl nitrates …) • Reduced organic gases (Aliphatic amines …..) • Reduced and oxidized organic nitrogen containing particulates.

  20. Continued • Wet Species (Current) • SO4 • NO3 • NH4 • Wet Species (Missing) • Organic nitrogen • Reduced • Oxidized • Biological/terrestrial

  21. Accuracy/Uncertainty (IMPROVE) • The species that are measured are done so with reasonable accuracy and precision

  22. Accuracy/Uncertainty (CASTNET/NADP) • SO2/SO4 measured reasonable well for both wet and dry • Nitrogen is problematic across the board • Cut point is ill defined (coarse vs fine) • HNO3/NO3 split has large error • NH4 error (underestimated) may be on order of 20-50% • NH4 and NO3 may be biological converted over the course of a week.

  23. What isn’t measured? • NH3 • Organic nitrogen either in wet or dry (gas and particle phase) or its reduced, oxidized or biological forms • NO2, peroxyacetyl nitrate (PAN) and related alkyl nitrates • Aliphatic amines • Proteins, amino acids, etc

  24. How important is AON? • 51 studies in North America have DON at 38±19% of TON (Wet) • As much as 30% of particulate OC is nitrogen containing • Gas % of TON ?

  25. Wet DON • Can measure TON • Can’t directly measure reduced, oxidized, or biological ON – important to make these distinctions from an apportionment perspective because sources are distinctive • Can use receptor type models to apportion wet DON if one has reliable chemical markers • Measure reduced OC markers such as amines and urea for reduced DOC • Measure oxidized OC markers such as alkyl nitrates, nitrophenols, and other nitroaromatic • Measure biological markers such as amino acids and peptides • Apply simple regression models or more sophisticated models such as PMF and UNMIX.

  26. Dry gas and particle ON • Can measure both oxidized and reduced ON both in gas and particle phase using catalytic converters and collect in near real time.

  27. Recommendations from EPA NAAQS review: deposition index from NOX/SOX review • We recommend monitoring a suite of reactive nitrogen species the sum of which is “Total Chemically Reactive Nitrogen” defined as the sum of all oxidized species except N2O and the sum of ammonia and ammonium. • Total Chemically Reactive Nitrogen = NOy + NHx + ? • Species Method NOy (total oxidized nitrogen) Reduction to NO followed by chemiluminescence NO3- (particulate nitrate) Denuder/filter sampling followed by ion chromatography HNO3 (nitric acid vapor) Filter/denuder and followed by ion chromatography. NH3 (ammonia) Filter/denuder followed by colorimetry or ion chromatography NH4+ (ammonium) Denuder/filter followed by colorimetry or ion chromatography

  28. Questions • Is split between various species important • SO2/SO4, HNO3/NO3, NH3/NH4, etc or is total sulfur, or total gas/particle phase reactive nitrogen adequate? • For ecosystem response may not be so important? • For attribution and model assessment it is critical! • Can defensible critical loads be set without a knowledge of total nitrogen? • What sampling frequency/duration is acceptable – both in time and space?

  29. Temporal Considerations Critical for source apportionment

  30. Time series of PILS and IMPROVE sulfate and nitrate

  31. Time series of PILS data

  32. APPORTIONMENT QUESTIONS Many issues here but will focus on smoke

  33. Increasing Information Needs

  34. Contribution of Fires to Particulate Carbon Wildfire Agricultural Fire Prescribed Fire Residential Wood Burning

  35. Contributions from Biomass Burning Smoke Impacting Yosemite NP Summer 2002 SOA from smoke and other sources Primary Smoke Biomass burning can have significant primary and secondary particulate carbon contributions

  36. Aging Rapidly Creates Lots of SOA Wall-loss Corrected (g/m3)

  37. Hybrid Source Apportionment Model Chemistry Source Impacts Air Quality Meteorology Source-compositions (F) Receptor model C=f(F,S) Receptor (monitor) Source-oriented Model (3D Air-quality Model)(CMAQ, CAMx) Receptor Model(CMB, PMF) Jeameen Baek et al., - Georgia Institute of Technology

  38. Smoke Management Needs for Air Quality Regulations Develop an unambiguous routine and cost effective methodology for apportioning primary and secondary carbonaceous compounds in PM2.5 RETROSPECTIVELY to prescribed, wildfire, agricultural fire, and residential wood burning activities Daily contributions needed for Haze Rule to properly estimate natural contribution and contribution to worst 20% haze days Annual and daily contributions needed for PM2.5 and PM10 NAAQS Long term data needed to assess successes of smoke management policies Similar needs for ozone and reactive nitrogen deposition issues

  39. Smoke Apportion: Receptor Modeling PMF type models with IMPROVE data retrieves a smoke/SOA factor – dominate contributor to contemporary carbon in rural areas IMPROVEData Receptor Model Source Profiles Source Factors Mobile Source Other Sources Primary + Secondary Smoke + Vegetation SOC

  40. Smoke Apportion: Receptor Modeling Addition of primary smoke marker species allows the separation of primary smoke from SOC Primary Smoke Marker Species IMPROVEData Receptor Model PMF/other Source Profiles Source Factors Mobile Source Other Sources Secondary Smoke + Vegetation SOC Primary Smoke

  41. Smoke Apportion: Hybrid Receptor Modeling Addition and incorporation of prior source attribution results in a hybrid receptor model can separate both primary and secondary smoke from other sources Primary Smoke Marker Species IMPROVEData Source Oriented Transport Model (All fires) Receptor Model Hybrid PMF Source Profiles Source Factors Mobile Source Other Sources Vegetation SOC Primary & Secondary Smoke

  42. Smoke Apportion: Hybrid Receptor Modeling By tagging the prior source attributions by the fire type and the fire location, the contributions of fire can be apportioned to specific fire types and locations Source Oriented Transport Model + Fire Types Primary Smoke Marker Species IMPROVEData Secondary Smoke Marker Species Hybrid Receptor Model Source Factors Source Profiles Wild Fire Mobile Source Other Sources Other SOC sources Primary & Sec Smoke Prescribed Fire Agricultural Fire

  43. Fraction Biogenic - Summer 2004-05 The summer (June-August) IMPROVE carbon data were partitioned into fossil and biogenic carbon using the derived fossil and biogenic EC/TC ratios

  44. Fraction Biogenic - Winter 2004-06 The summer (December - February) IMPROVE carbon data were partitioned into fossil and biogenic carbon using the derived fossil and biogenic EC/TC ratios

  45. Contribution of Secondary Organic Carbon during the Summer • Assumes all winter organic carbon is primary • Underestimates the summer secondary particulate carbon • Assumes that a similar mix of sources contribute to the particulate carbon in the summer and winter. • Impact on estimate is unknown

  46. Sources of Carbon

  47. SMOKE MARKER NEEDS • Minimally need to measure laevoglucose + other primary smoke markers • Identify secondary makers • Modeled markers? (various options)

  48. WHAT DO WE NEED TO MEASURE ? ***** Measure with high degree of accuracy **** Measure with reasonable accuracy *** Measure with low accuracy ** Research monitoring * Currently cannot do Note: measurements should be event based for wet deposition and gases and particles measured at least on a 24 hr schedule.

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