slide1
Download
Skip this Video
Download Presentation
NACP

Loading in 2 Seconds...

play fullscreen
1 / 32

NACP - PowerPoint PPT Presentation


  • 162 Views
  • Uploaded on

NACP. On network design for the detection of urban greenhouse gas emissions: Results from the Indianapolis Flux Experiment (INFLUX).

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' NACP' - ida


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

NACP

On network design for the detection of urban greenhouse gas emissions: Results from the Indianapolis Flux Experiment (INFLUX)

Natasha Miles1, Marie Obiminda Cambaliza2, Kenneth Davis1, Michael Hardesty3, Laura Iraci4, Kevin Gurney5, Anna Karion3, Thomas Lauvaux1, Laura McGowan1, Scott Richardson1, Daniel Sarmiento1, Paul Shepson2, Colm Sweeney3, Jocelyn Turnbull6, James Whetstone7

1. The Pennsylvania State University, 2. Purdue University, 3. NOAA/ESRL

4. NASA/JPL, 5. Arizona State University, 6. GNS Science, 7. NIST

ICDC9 Beijing7June 2013

influx motivation
INFLUX motivation
  • Emissions mitigation will happen at local and regional scales.
  • Validation of emissions mitigation will(?) require (independent) measurements
  • Atmospheric GHG measurements have the potential to provide such independent emissions estimates.
slide3

INFLUX objectives

  • Develop improved methods for determination of urban area-wide emissions, and spatially and temporally-resolved fluxes of greenhouse gases, specifically, CO2 and CH4.
  • Determine and minimize the uncertaintyin the emissions estimate methods.
slide4

INFLUX methodology:

Simultaneous application of multiple methods

    • Inventory estimates of sector-by-sector emissions at high spatial resolution
  • Periodic aircraft flights with CO2, CH4, and flask samples - Whole city flux estimates
  • Periodic automobile surveys of CO2 and CH4 – Emissions from strong point sources (power plants, landfill, gas leaks)
  • 12 surface towers measuring CO2, 5 with CH4, and 5 with CO & Mesoscale atmospheric inversion - Spatially and temporally resolve GHG emissions
  • 5 automated flask samplers from NOAA – Identify sectoralemissions
  • TCCON-FTS for 4 months (Sept-Dec 2012)
  • 4 eddy-flux towers from natural to dense urban landscapes – Model assessment (June 2013)
  • Doppler lidar (installed late April 2013)
  • Tracer release experiment (planned August 2013)
vulcan and hestia emission inventories models
Vulcan and Hestia Emission Inventories / Models

250m res - Indy

Hestia: high resolution emission data for the residential, commercial, industrial, transportation and electricity production sectors.

Vulcan – hourly, 10km resolution for USA

http://hestia.project.asu.edu/

slide8

1 June 2011 Results

Cambaliza et al, in prep

50 ppb CH4

8 ppm CO2

22,000 moles s-1

203 moles s-1

slide9

CO2 Emissions: Aircraft mass balance vs Hestia inventory

  • Aircraft mass balance: uncertainty based on measurements of plume at different distances from source: 40%
  • More day-to-day variability in mass balance results

Cambaliza et al, in prep

slide10

Drive-arounds: Separation/quantification of CH4 sources

WWTP

Instrumented

surface vehicles to

identify and quantify individual sources.

Landfill

slide11

INFLUX observational results to date:

Ground-based measurements

in situ flask comparison at 5 influx sites
In-situ – flask comparisonat 5 INFLUX sites
  • NOAA 1 hour integrated flask samples
  • Mean value in-situ - flask:
    • CO2: 0.09 ppm
    • CH4: 0.6 ppb
    • CO: -4.1 ppb
  • Within WMO recommendations (urban)
slide14

Flask results: C14

ICDC9 Poster 224: Turnbull et al.

slide15

Tower in-situ results /

Mesoscaleatmospheric inversion system

mesoscale modeling system
Mesoscale modeling system
  • WRF-Chem running with:
    • 3 nested domains (9/3/1 km resolution), inner domain: 87x87 km2
    • Meteorological data assimilation
    • Hestia anthropogenic fluxes for the inner domain
    • Vulcan anthropogenic fluxes for the outer domains
    • Carbon Tracker posterior biogenic fluxes
    • Carbon Tracker boundary conditions
  • Lagrangian Particle Dispersion Model
  • Bayesian matrix inversion

T. Lauvaux

gain relative improvement prior vs posterior

Inversion system test

Gain – relative improvement prior vs. posterior

Flux units: gC m-2 hr-1.

Very good system performance within the tower array.

Very idealized case, but encouraging nonetheless.

1 = perfect correction to prior fluxes

influence functions influx
Influence functions: INFLUX
    • “Influence function” – the areas that contribute to GHG concentrations at measurement points
  • 12 towers in 87 x 87 km2 domain
  • Strategy: oversampling (?)

Contour: Hestia residential sector

sectoral atmospheric mole fractions tower by tower
Sectoral atmospheric mole fractions, tower by tower

Winter mean mole fractions

6 of 12 tower sites

Midday ABL mixing ratio (ppm)

Site 1: background

Site 2: downwind

Site 10: powerplant!

Some structure across

towers by sector

Site 1

Site 10

2

5

9

7

commer

indust

mobile

resid

powerplant

slide20

Comparison of [CO2] at INFLUX sites

  • Afternoon [CO2] with 21-day smoothing
  • Site 03 (downtown): high [CO2]
  • Site 09 (rural site to the east of the city): low [CO2]
  • Seasonal and synoptic cycles are evident

Site 03: downtown

Site 09: rural

2012

* Note: Tower heights range from 40 m AGL to 136 m AGL

observed range of co2 amongst influx sites
Observed range of CO2 amongst INFLUX sites

< 3 ppm on 29% of days

> 10 ppm on 10% of days

observed range of co2 amongst influx sites1
Observed range of CO2 amongst INFLUX sites

< 3 ppm on 29% of days

> 10 ppm on 10% of days

29% of ranges are < 3 ppm

10% of ranges are > 10 ppm

co2 range as a function of wind speed
CO2 range as a function of wind speed

Observations: CO2 range amongst INFLUX sites

Increased residence time (at low winds) tends to increase the CO2 range

co2 range as a function of wind speed1
CO2 range as a function of wind speed

Observations: CO2 range amongst INFLUX sites

Model: Difference along domain-averaged wind direction

Increased residence time (at low winds) tends to increase the CO2 range

average co2 above background site
Average [CO2] above background site
  • Compared to Site 01 (background)
  • Site 03 (downtown site) measures larger [CO2] by 3 ppm
  • Site 09 measures only 0.3 ppm larger than Site 01

Average CO2 (ppm)

Observations

Afternoon hours

Downtown site

Background site

East of city

01 02 03 04 05 07 09 10 12

average co2 compared to background site
Average CO2 compared to background site

Average CO2 (ppm)

  • Forward model results: using Hestia 2002 fluxes
  • Average: obs 25% higher than predicted

Background site

01 02 03 04 05 07 09 10 12

average co2 compared to background site1
Average CO2 compared to background site

Average CO2 (ppm)

  • Forward model results: using Hestia 2002 fluxes
  • Average: obs 25% higher than predicted

Background site

01 02 03 04 05 07 09 10 12

conclusions

NACP

Conclusions
  • Whole city flux estimates achieved via aircraft mass balance. ~40% uncertainty
  • Winter, CO2 = CO2ff. Summer, not so.
  • Tower observations detect a clear urban signal in both CO2 and CH4 (buried amid lots of synoptic “noise”).
  • Differences vary greatly with weather conditions
  • Inversion system with 6 towers performs very well under idealized conditions.
  • “Real data” forward results encouraging.
vertical profiles of co2
Vertical profiles of CO2

Rural site

October 2012

vertical profiles of co21
Vertical profiles of CO2

Downtown site

October 2012

Rural site

October 2012

  • Downtown site, compared to the top level (54 m):
    • 40 m level is 0.3 ppm higher, averaged over 1 month
    • 20 m level is 1.7 ppm higher
    • 10 m level is 4.3 ppmhigher
  • INFLUX tower heights range from 40 m AGL to 136 m AGL
sensitivity test average co2 above background site
Sensitivity test: Average [CO2] above background site
  • Check sensitivity of results to small errors in modeled winds
  • Hestia fluxes shifted by 1 grid point in each direction
  • Which sites are more useful for reducing uncertainty?

Background site

sensitivity test average co2 above background site1
Sensitivity test: Average [CO2] above background site
  • Check sensitivity of results to small errors in modeled winds
  • Hestia fluxes shifted by 1 grid point in each direction
  • Which sites are more useful for reducing uncertainty?
  • Differences of 0.5 – 1 ppm at sites 03, 07, and 10
  • Lower at other sites

Background site