The winter of our oil & gas emissions, made glorious

by measurements

Seasonality oil & gas emissions?

Uncertainties in methane emissionsMethod to quantify: tracers flux ratio

Tracers to identify emissions or air mass

Mobile lab in Western US Wintertime Study

Seasonal Natural Gas Use

= 29 million kg hr-1

Anecdote: unattended production at sites with additional treatment (e.g. ‘wet’ gas) fare poorly in cold weather

Seasonality oil & gas emissions?

Utah Wells

Pneumatic valves, liquids unloading, condensate tank top emissions

Site Level (bottom-up) Basin Scale (top-down)

Component scale Flight Mass BalanceActual Site scale*

vsEmission Inventory

Activity Factors Φ Emission Intensities

*multi-tracer flux ratio

ozone precursor emissions

Scott Herndon

ChristophDyroff

Tara Yacovitch

Conner Daube

BillLong

BerkKnighton

Aerodyne Mobile Laboratory (AML)

Instrument subsetCH4, C2H6, N2O, HCN,

C2H2, CO2, O3, CO, HCHOVocus

HR-AMSFrancesca

Majluf

Rob Roscioli

Jordan Krechmer

JasonCurry

Industrial Emissions Characterization“wet gas” region

West Virginia April 2018

tracer

No-tracer

Emission CH4 = (downwind CH4 / tracer) * Emission tracer

Want to know knownMeasured in transects

Lamb et al, 1995; Czepiel et al., 1996, 2003; Börjesson et al, 2009; Mønster et al., 2014; Roscioli et al., 2015; Yacovitch et al., 2017;

Method to quantify: tracers flux ratio

Site 59

F(CH4) = CH4/C2H2 x F(C2H2)

CH4/C2H2

Methane Emission Rate

F(CH4) = 7.2 x F(C2H2)

“dry gas” regionTexas

September 2019

Method to quantify: tracers flux ratio

Site ID 59

Tracer at Tank

Tracer at Well NWith unusual sound

xylene

CH4, C2H6,

C2H2 N2O

The dominant source at this site is the north well (with an unusual sounding pneumatic). The second well is emitting much less. The tanks are also emitting, with aromatics.

Wind from E

Emission intensity linked to on-site activityActivity Factors Φ Emission Intensities

Like the deliberate ‘tracers’ the chemical dimension brought by other measurementsenhances CO2, CH4, N2O measurements

Inspired by -> Observed iso- and n-pentane mixing ratios at various sites in Colorado and two cities (Houston, TX and Pasadena, CA).[Gilman et al., 2013]

i-pentane and n-pentane mixing ratios observed during Texas AQRP 2017

Ratio of iso- to n-pentane mixing ratio for two sampling sites.

Tracers to identify emissions or air mass

Example of urban source attribution: Boston manhole CH4and C2H6 concentrations

Manholes with low methane content have low and high ethane content

Manholes with high methane content also have high ethane content

• Ethane content provides information about the sources (biogenic vs NG) in urban settings

• Manholes with high CH4 are dominated by natural gas, not biogenic “sewer” gas

% e

than

e

Freq

uenc

y

[CH4]

Tracers to identify emissions or air mass

Tracers to identify emissions or air massLike the deliberate ‘tracers’ the chemical dimension brought by other measurementsenhances CO2, CH4, N2O measurements

Mobile ground measurements resolve substantial changes in atmospheric composition

Relevant to wintertime vertical gradients in SLC

AMS HR-Orgµg m-3

NOAA FIREX - 2018

Using topography to advantage

Mobile Lab can measure within an urban boundary layer and quantify the residual layers above by using topography

DOE/NSF Milagro 2006

In addition to on road travel at different altitudes, mobile measurement will be coupled to drone-based transect to explore vertical gradient when road access is unavailable

Mobile lab in Western US Wintertime Study

Identifying and Apportioning Ozone Producing Volatile Organic Compounds in Central Texas

AQRPMay 2017

Aerodyne Research, Inc.Drexel University

Montana State UniversityEnvironment Canada

University of Texas (Austin/San Antonio)University of Houston

Baylor University

SummarySeasonality oil & gas emissions? Yes and no

Uncertainties in methane emissions

on-site activity factors & emissions with

research endeavor can match top-downMethod to quantify: tracers flux ratio

on-site/whole-site can be quantified

Tracers to identify emissions or air masschemical signatures are inherent ‘tracers’

Mobile lab in Western US Wintertime Study

AML could be used to look at spatial and vertical composition gradients

Power and Volume

(optional, see me)

Dual TILDASTunable

Infrared Direct Absorption

SpectrometerNO, NO2

Mini TILDASCH4, C2H6

Mini TILDASCO, N2O, H2O

Mini TILDASHCHO, H2O CO2

Licor N.D. IR

O3UV Absorption

GPSARISensePM2.5, PM10,

CO, NO, NO2, etc.

Live Display

PTR-MSProton-Transfer

Mass Spec.

H2S, HCN, aromatics, other

VOCs

CO2Licor N.D. IR

RH, Press. Temp.

Wind

VOCUSHigh-Res. Proton-

Transfer Mass Spec.

Aromatics (BTEX), acetone, methyl & ethyl mercaptans, other VOCs

AML Schematic, 2019

Environmental Defense Fund Offshore

EDF - OffshoreFebruary 2018

LouisianaTexas

Industrial Emissions Characterization

South Coast Air Quality

Management District

March 2018

Los Angeles, CA

aCougarTwisp

McCallBase at Activity Barn

AML ground track450 mi. 350 mi.

Rattlesnake50 mi. Rabbit Foot

200 mi.

Missoula

Boise

FIREX – August, 2018 Field Deployment, Idaho & Washington

Lon. ->

Lat.

->

Tracer Flux Ratio quantifies CH4 through correlation with tracer

Emission CH4 = (downwind CH4 / tracer) * Emission tracer

Want to know knownMeasured in transects

Lamb et al, 1995; Czepiel et al., 1996, 2003; Börjesson et al, 2009; Mønster et al., 2014; Roscioli et al., 2015

Early, this work employed one tracer, N2O we took single cylinder of aux. tracer C2H2

Oil and gas facilityof any size

Correlated Methane and Nitrous Oxide Plumes

CH4

N2O

C2H6

Map with transect

NAL 102 MEDR 2-19-39-3 Production Site 52.36506916, -114.417315

The winter of our oil & gas emissions, made glorious by measurementsSeasonal Natural Gas UseUtah WellsSlide Number 4Industrial Emissions CharacterizationSlide Number 6Site ID 59Emission intensity linked to on-site activityLike the deliberate ‘tracers’ �the chemical dimension brought by other measurements�enhances CO2, CH4, N2O measurementsSlide Number 10Like the deliberate ‘tracers’ �the chemical dimension brought by other measurements�enhances CO2, CH4, N2O measurementsSlide Number 12Using topography to advantageSlide Number 14Identifying and Apportioning Ozone Producing Volatile Organic Compounds in Central TexasSummarySlide Number 17Environmental Defense Fund OffshoreIndustrial Emissions CharacterizationaTracer Flux Ratio quantifies CH4 through correlation with tracerSlide Number 22