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 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)

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

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)

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 NADP 2004 Annual Summary Burns (2003) Niwot Saddle NADP site

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

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. STATEMENT OF THE PROBLEM ROcky Mountain Atmospheric Nitrogen and Sulfur study (ROMANS)

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 Concerns about increasing reactive nitrogen in Rocky Mountain National Park (Typical of all high mountainous regions)

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.

The urban/industrial- agricultural interface NO x HNO 3 + NH 3  NH 4 NO 3 (p) +hv Organic nitrogen? ??? VOC

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: NH 3, R-NH 2, NO X (NO+NO 2 ), NO Y (HNO 3, PAN, etc) – PARTICLE: NH 4, NO 3, ORGANICS (reduced and oxidized)? – WET (rain and clouds): NH 4, NO 3, 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. 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: NH 3, R-NH 2, NO X (NO+NO 2 ), NO Y (HNO 3, PAN, etc) – PARTICLE: NH 4, NO 3, ORGANICS (reduced and oxidized)? – WET (rain and clouds): NH 4, NO 3, 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. ROMANS OBJECTIVES

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

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

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

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 not currently being measured. SOME PRELIMINARY RESULTS

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

IMPROVE (24 hr every third day) Dry Species (Current) –SO 4 –NO 3 –Total POM –Metals (soil and attribution) Dry Species (Missing) –NH 3 /NH 4 –Reduced and oxidized organic nitrogen containing particulates –NO x (NO and NO 2 ) –Oxidized organic gases (PAN - alkyl nitrates …) –Reduced organic gases (Aliphatic amines …..)

CASTNET (weekly) Dry Species (Current) –SO 2 /SO 4 –HNO 3 /NO 3 –NH 4 Dry Species (Missing) –NH 3 –NO x (NO and NO 2 ) –Oxidized organic gases (PAN - alkyl nitrates …) –Reduced organic gases (Aliphatic amines …..) –Reduced and oxidized organic nitrogen containing particulates.

Continued Wet Species (Current) –SO 4 –NO 3 –NH 4 Wet Species (Missing) –Organic nitrogen Reduced Oxidized Biological/terrestrial

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

Accuracy/Uncertainty (CASTNET/NADP) SO 2 /SO 4 measured reasonable well for both wet and dry Nitrogen is problematic across the board –Cut point is ill defined (coarse vs fine) –HNO 3 /NO 3 split has large error –NH 4 error (underestimated) may be on order of 20-50% –NH 4 and NO 3 may be biological converted over the course of a week.

What isn’t measured? NH 3 Organic nitrogen either in wet or dry (gas and particle phase) or its reduced, oxidized or biological forms –NO 2, peroxyacetyl nitrate (PAN) and related alkyl nitrates –Aliphatic amines –Proteins, amino acids, etc

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 ?

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.

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.

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 N 2 O 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 NO 3 - (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

Questions Is split between various species important –SO 2 /SO 4, HNO 3 /NO 3, NH 3 /NH 4, 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?

Temporal Considerations Critical for source apportionment

Time series of PILS and IMPROVE sulfate and nitrate

Time series of PILS data

APPORTIONMENT QUESTIONS Many issues here but will focus on smoke

Increasing Information Needs

Contribution of Fires to Particulate Carbon Wildfire Prescribed FireResidential Wood Burning Agricultural Fire

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

Aging Rapidly Creates Lots of SOA Wall-loss Corrected (  g/m 3 )

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

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

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

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

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 IMPROVE Data Hybrid PMF Mobile Source Source Factors Source Profiles Other Sources Primary Smoke Marker Species Primary & Secondary Smoke Vegetation SOC Source Oriented Transport Model (All fires) Receptor Model

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 IMPROVE Data Hybrid Receptor Model Mobile Source Source Factors Source Profiles Other Sources Primary Smoke Marker Species Primary & Sec Smoke Other SOC sources Source Oriented Transport Model + Fire Types Secondary Smoke Marker Species Agricultural Fire Prescribed Fire Wild Fire

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

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

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 Secondary TC Secondary OC Biogenic36% (6.4)41% (7.3) Fossil23% (10)36% (15)

Sources of Carbon PrimarySecondary Biogenic Smoke - Wildfire, Agriculture and residential wood & open burning Pollen Soil Cooking Smoke - Wildfire, Agriculture and residential wood & open burning Vegetation Fossil Combustion – Mobile (Automobile, Diesel) – Off Road Mobil – Oil/gas – Coal (power generation, industry) Combustion –Mobile (Automobile, Diesel) – Off Road Mobil – Oil/gas – Coal (power generation, industry) Evaporative loss of

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

***** 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. WETGASPARTICLE Temporal scale (gas/particle) SO 2 /SO 4 -2 ************** Min/hr/day/week NO 2 /HNO 3 - /NO 3 - ********(***CASTNET) Min/hr/day/week NH 3 /NH 4 - *** Min/hr/day/week Total ON***** Integrated sample/event based ON r * (markers) *** (markers) Min/hr/day/week (gas/part) Event for markers ON o * (markers) *** Min/hr/day/week (gas/part) Event for markers ON b * (markers) ** Integrated WHAT DO WE NEED TO MEASURE ?

Monitoring NHx at a number of regionally representative sites NO y /NO r at a number regionally representative sites Wet ON at a number of regionally representative sites Smoke markers at a few sites

Meteorology Air Quality Source-compositions (F) Source-oriented Model (3D Air-quality Model) (CMAQ, CAMx) Receptor (monitor) Receptor Model (CMB, PMF) Source Impacts Chemistry Receptor model C=f(F,S) Need a data base of ground based measurements, satellite data, and model runs for a integrated analysis

Next Steps? Develop denuders to do NH 3, NH 4, and HNO 3 /NO 3 split (within 6 months – year) Establish/examine need for ON measurements at x number of sites? Test filter based measurements for gas/particle phase oxidized ON measurements (1+ years) Develop marker technology/methodology for apportioning ON in wet deposition (2+ years ?) Do the same for reduced gas/particles (time ?) Implementation schedule (Funding??)

SpeciesMethod NOy (total oxidized nitrogen)Reduction to NO followed by chemiluminescence NO 3 - (particulate nitrate)Denuder/filter sampling followed by ion chromatography HNO 3 (nitric acid vapor)Filter/denuder and followed by ion chromatography. NH 3 (ammonia)Filter/denuder followed by colorimetry or ion chromatography NH 4 + (ammonium)Denuder/filter followed by colorimetry or ion chromatography Tabular summary WHAT’S MISSING: ORGANIC NITROGEN

Northern Rockies Wildfire Impacts

2005 Agricultural Fires

Southern California Fires Husar et al., 2007

NOTE NOy ≡ NO + NO2 + NO3 + 2xN2O5 + HNO3 + HONO + HO2NO2 + RONO2 (organic nitrates such as PAN and alkyl nitrates) + RONO (organic nitrites) + NO3- (particulate nitrate). The ecology community defines “Total Reactive Nitrogen” to include N2O which is not reactive in the sense considered here, thus we define “Total Chemically Reactive Nitrogen” to exclude N2O and N2.

Emissions from Different Fire Types Wildfire and wildland fire use, “Natural fires”, are the largest sources of smoke, especially in the western United States.