Urban Development and Gas Flaring Mapping with VIIRS Nighttime Data

1. Mapping urban development and gas flaring activity with nighttime VIIRS data Chris Elvidge Earth Observation Group NOAA-NESDIS National Geophysical Data Center 325 Broadway, Boulder, Colorado 80305 USA Tel. 1-303-497-6121 Email: chris.elvidge@noaa.gov Kimberly Baugh, Mikhail Zhizhin, Feng Chi Hsu Cooperative Institute for Research in Environmental Sciences University of Colorado, Boulder, Colorado USA June 22, 2012

2. Lights At Night! Boats Cities Industrial Sites Gas Flares Fires

3. Artificial lighting is a excellent remote sensing observable!

4. Two Satellite Systems Collect Global Low Light Imaging Data at Nights In both cases the purpose of the low light imaging is the detection of moonlit clouds. An instrument optimized for observing nighttime lights has not yet been flown. U.S. Air Force Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS). 1972 to present. NASA-NOAA Suomi NPP Visible Infrared Imaging Radiometer Suite (VIIRS). Launched October 28, 2011.

5. DMSP Nighttime VisibleMay 21, 2012 at ~19:30 local time

6. NGDC has produced a time series of DMSP annual cloud-free nighttime lights composites (1992-2011) Available at:

7. Applications for satellite observed nighttime lights • Spatial proxy for human variables • Population • Economic activity • Fossil fuel CO2 emissions • Exurban development • Density of constructed surfaces • Urbanization rates • Habitat fragmentation / encroachment • Nocturnal lighting impacts • Astronomical conditions • Site selection for astronomical observatories • Ecological studies • Human health studies • Disaster monitoring • Detection of power outages • Tracking power grid recovery • Estimation of gas flaring volumes • CO2 emission estimates • Support to gas flaring reduction efforts • Fisheries • Estimation of fishing stocks based on catch per unit effort (CPU) • Detection of illegal, unregulated, unreported (IUU) fishing

8. VIIRS vs OLS Milan Region, January 8, 2012 OLS VIIRS 14 bit quantization 750 m GSD ~750 m GIFOV 1:30 am overpass Radiometric calibration No saturation 6 bit quantization 2.7 km GSD 5 km+ GIFOV 8:00 pm overpass No in-flight calibration Saturation in urban center in operational data collections

9. VIIRS Nighttime Day / Night Band (DNB)May 21, 2012 at ~ 01:30 local time – zero moonlight

10. VIIRS versus DMSP May 21, 2012 OLS VIIRS

11. Detection of Villages in VIIRS Nighttime Visible (DNB)May 21, 2012 at ~ 01:30 local time VIIRS OLS

12. What Else VIIRS Has To Offer Fire detections - discriminate lights from combustion sources. Cloud optical thickness and snow cover to rate the quality of light detections. Clouds and their properties Fires Snow cover

13. What is being developed Light detection algorithm that can work through stray light Terrain correction – DNB data are not terrain corrected since the primary mission is detection of moonlit clouds. Atmospheric correction – to estimate upwelling radiances at the earth surface.

14. VIIRS Stray Light Stray Light Along track transect over open ocean

15. Light Detection Cross track transect with city lights - in stray light region

16. NGDC’s plan for a 2012 global nighttime lights from VIIRS Initial product will be a mosaic made with a relatively low number of repeat observation. October 2012. Subsequently a full year product will be processed to characterize the variability in lighting. March 2013. Participate in GEO SB-04 collaboration.

17. 2012-2015 Work Plan - Task SB-04: Task Lead: Qihao Weng, Indiana State University • Improve the overall coordination of urban observations, monitoring, forecasting, and assessment initiatives worldwide. • Support the development of global urban observation and analysis systems. • Produce up-to-date information on the status and development of the urban system – from local to global scale. • Fill gaps in integration of global urban observations with (i) data characterizing urban ecosystems, built environment, air quality, and carbon emission; and (ii) indicators of population density, environmental quality, and quality of life; and (iii) patterns of human, environmental and infectious diseases. • Develop innovative concepts and techniques in support of effective urban sensing and sustainable urban development.

18. Task Outputs / Activities, 2012-2015 Targets by 2015 Action 1: GEO SB-04 Symposium in 2012 (in conjunction with EORSA2012) TARGET 1. Improve the overall coordination of urban observations, monitoring, forecasting, and assessment initiatives worldwide. Action 2: Book - Global Urban Monitoring and Assessment thru Earth Observation. Action 3: GEO SB-04 Symposium in 2013 (in conjt with JURSE2013) TARGET 2. Support the development of global urban observation and analysis systems. Action 4: Develop EU-China collaboration in urbanization monitoring within the Dragon 3 programme Action 5: Generation and provision of data set on spatio-temporal development (1975-2010) of actual 26 mega-cities. TARGET 3. Produce up-to-date information on the status and development of the urban system – from local to global scale. Action 6: Set-up of global data base of binary settlements masks (Global Urban Footprint 2012/2013) derived from SAR data of TanDEM-X mission. Action 7: The USGS will accomplish 2011 impervious surface and urban land cover mapping for the conterminous United States. TARGET 4. Fill gaps in integration of global urban observations with (i) data characterizing urban ecosystems, built environment, air quality, and carbon emission; and (ii) indicators of population density, environmental quality, and quality of life; and (iii) patterns of human, environmental and infectious diseases. Action 8:Construction of a 2012 nighttime lights of the world using Suomi NPP VIIRS data (NOAA-NGDC). Action 9: GEO Grid/AIST and the University of Tokyo are developing ASTER Global Urban Area Map (3734 cities of more than 0.1 million). Action 10:The National Observatory of Athens is developing advanced methodologies for the study of the thermal environment of cities. Action 11: Developing methods to monitor high resolution dynamics of land reflectance in China TARGET 5. Develop innovative concepts and techniques in support of effective urban sensing and sustainable urban development. Action 12: Participate in NASA’s HyspIRI Science Study Group.

19. Gas Flaring Widely used practice for disposing of natural gas at oil production facilities in remote or impoverished areas. Volume estimated at 138 billion cubic meters in 2011 from DMSP data. About 1% of total fossil fuel CO2 emissions. Curtailing gas flaring is “low hanging fruit” for carbon emission reductions. Because of the lack of reporting – satellite remote sensing is the best approach for comprehensive monitoring of gas flaring.

20. VIIRS Gas Flaring Monitoring System Supported under the JPSS Proving Ground program Heritage – NGDC uses DMSP nighttime lights to estimate annual gas flaring volumes in 65 countries MODIS and VIIRS thermal anomalies are only processed on land – no coverage for offshore flares

21. End Users World Bank Global Gas Flaring Reduction (GGFR) initiative – will use the data to track the effectiveness of gas flaring reduction efforts. California Air Resources Board – will use the data to calculate the total carbon emissions associated with fuel imported into the state from various oil fields around the world. NOAA’s Carbon Tracker – spatial distribution and magnitude of carbon emissions from gas flaring.

22. Persian Gulf May 3, 2012Flares show up as “hotspot” in M12 (3.7 um) and M13 (4 um) M13 – the standard fire band M12

23. Persian Gulf May 3, 2012Many more flares show up as “hotspot” in M10 (1.61 um) M10 – more detections Less clutter – gas flares are Hotter than biomass burning M13 – the standard fire band

24. At Night Gas Flares Can Be Detected in Four Short Wavelength Bands DNB 0.7 um M7 0.865 um M10 1.61 um M8 1.24 um

25. Approach Gas flare detection at night using the M10 band Radiances extracted from DNB, M7,8,10,12,13,14,15,16. Flare temperature and radiant output estimated through Planck curve fitting Daily summaries will be distributed as kml for display in Google Earth Monthly and annual composites will be produced for estimation of flared gas volume and carbon emission

26. June 17, 2012 IR-sources

27. June 17, 2012 IR-sources

28. June 17, 2012 IR-sources

29. Estimating Flare Temperature and Radiant Output * = observed radiances • Simultaneousfitting assuming a hot source and a cooler background • Use observed radiances from M7,8,10,12,13,14,15,16 • Solve of flare and background temperatures and magnitudes simultaneously • Variables: TFLR, TBG, εFLR, εBG • Pros • No external background pixel required • Possibility to remove BG values • Accommodates high intensity flares with emission in M14-16 • Error can be estimated relative to observed radiances • May be used to filter South Atlantic Anomaly noise? • Cons • Constraints are requiredto guide the solutions • Poor performance expected for low intensity detections that lack detectable emission in M7-8 Modeled Radiant Emissions Background Radiation Flare Radiation

30. VIIRS Cloud Algorithm Identifies Flares as Cloud Cloud optical thickness M10 Basra, Iraq M13 Cloud mask Spectral confusion between clouds and gas flares

31. Summary VIIRS provides substantial improvements over DMSP for global observation of nighttime lights and gas flaring NGDC is developing the capability to produce global nighttime lights and gas flaring data products These will be made openly accessible