1. QUANTIFICATION OF METHANE SOURCE LOCATIONS AND EMISSIONS IN AN URBAN SETTING B51Q Characterizing, Modeling, and Extending Urban Metabolism II Eric Crosson, Picarro

2. 2 Quantification of Methane Source Locations and emission in an urban setting Contributors: –NOAA – Colm Sweeney Jocelyn Turnbull –Boston University – Nathan Phillips, Lucy Hutyra –Gas Safety Inc. - Robert Ackley –Picarro – Sze Tan, Chris Rella –Purdue University - Paul Shepson, Maria Obiminda Cambaliza –NIST - James Whetstone, Tony Bova, Kuldeep R. Prasad –NASA- Richard Koyler –Penn State University – Ken Davis, Scott Richardson

3. 3 Motivation The identification and quantification of greenhouse gas emissions from urban centers are becoming of more interest. Recent measurements indicate that urban emissions are a significant source of Methane (CH 4 ) and in fact may be substantially higher than current inventory estimates. As such urban emissions could contribute 7-15% to the global anthropogenic budget of methane*. * Wunch, D., P.O. Wennberg, G.C. Toon, G. Keppel-Aleks, and Y.G. Yavin, Emissions of Greenhouse Gases from a North American Megacity, Geophysical Research Letters, Vol. 36, L15810, doi:10.1029/2009GL)39825, 2009.

4. 4 The Problem: Quantifying CH 4 Emissions using a Network of Analyzers, Establishing priors. Tall or Cell Phone Towers GHG emissions extracted using WRF-CHEM inversion models For CO 2 - use inventories such as Vulcan as a starting point. For CH 4 - no such starting point exist.

5. 5 Develop methodologies to identify methane source locations and gather information on methane flux signals to use as priors. –Total methane emissions. –Partition methane emissions both by source and geographically within an urban center. –Develop methods that enable fast and accurate data collection and “real time” processing. Objectives of this effort

6. 6 Measurements Real-time Met data Atmospheric Models Oil & Gas processing 10 kg/min Emissions Maps Taking a “snap shot”: Speed, specificity, and real-time feedback are the keys to success A powerful combination of new technologies is enabling scientist to generate high quality data at rates never before possible. auto flight

7. 7 For example: Brisbane, CA (methane map) Brisbane, CA San Francisco Brisbane 5 miles

8. 8 Speed is “everything”: Getting a “snap shot”, lot of area to cover in precious little time Brisbane, CA Bay Area: 21,442 miles of road* *Metropolitan Transportation Commission (2003)

9. 9 Accuracy- What is the source? Petroleum Facility Uncultivated Areas Brackish water Little or no wind Brisbane, CA

10. 10 Methane Signals Can be Confusing Natural Gas Vehicles Inefficient Vehicles Storm Drains Natural Gas Leaks Sewer Systems Petroleum Facilities Landfills

11. 11 Specificity: isotopic carbon-13 CH 4 measurements How can one help to identify the source? -37.2 per mil -45.7 per mil

12. 12 Specificity: isotopic measurements while driving at the speed of traffic Natural gas Conc (ppm) Delta (permil) Unknown Brisbane, CA

13. 13 Brisbane Site: looking from another angle Brisbane, CA Petroleum Facility Delta = -53.3 per mil Uncultivated Area Old Landfill

14. 14 Methane Capture System Leaks Brisbane, CA Petroleum Facility Old Landfill Delta = -53.3 per mil Large Area Leak

15. 15 Old landfill releasing methane in only two ways 1.Pipe connectors leaks. 2.Methane capture system is failing in one area of landfill. Take away: In a very short time, able to identify specific problems that may or may not be easily rectified by landfill owner or city fathers.

16. 16 Quantifying Methane Source Emissions Driving speeds of 20-30 mph Vacaville landfill Late evening wind conditions were very stable: –Speed 8.2 ±1.3 m/s –Direction 224.2 ± 5.0 deg wind

17. 17 Analyzing line integration data in real time to provide immediate feedback Post process data using more complex models at a later time Source Location from model

18. 18 Flux chamber measurements obtained using fast, high precision CH 4 analyzers. 45 feet 4 feet Leak Flux Using chamber measurements, one can obtain a lower limit on the total leak rate Found leaks ranging from 40 -300 sccf/day. As a guideline, the natural gas used in the “average” American home is 200 standard cubic ft per day. Leak Rate > 41 cubic ft per day Methane is coming out of the road.

19. 19 Ready to tackle more complex systems?.....Methane Emissions in Indianapolis Wind direction, Day 2 Methane Concentration levels are 3 times ambient 4 km from the landfill. Wind direction, Day 1 Emissions from these locations on landfill Little or no emissions from waste water treatment plant Unknown source of methane Natural Gas leak after gas station fire a few days earlier

20. 20 Summary Developed fast methodologies for identifying methane source locations and gathering information on methane flux signals to use as priors. For 2012: –Continue developing fast methodologies –Measure methane emission in several urban centers Indianapolis Boston San Francisco / Bay Area Paris