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MASTER: Fire Influence on Air Quality (FIREX-AQ), Western-Central USA, Summer 2019

Documentation Revision Date: 2021-09-30

Dataset Version: 1

Summary

This dataset includes Level 1B (L1B) data products from the MODIS/ASTER Airborne Simulator (MASTER) instrument. The raw data were collected as part of the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) program during 21 flights aboard a NASA DC-8 aircraft over the central and western USA from 2019-07-22 to 2019-09-03. The purpose of these flights was to measure emissions and to characterize the aerosols in the smoke plume above and downwind of the fire, and determine the overall spatial extent of wildfires and prescribed fires. Data products include L1B multispectral imagery in 50 bands covering wavelengths of 0.460 to 12.879 micrometers.

The MODIS/ASTER Airborne Simulator (MASTER) is a modified Daedalus Wildfire scanning spectrometer that flies on a variety of multi-altitude research aircraft and provides spectral information similar to that provided by the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), which are aboard two NASA Earth Observing System Satellites, TERRA & AQUA.

The overarching objective of the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) program is to provide measurements of trace gas and aerosol emissions for wildfires and prescribed fires in great detail, relate them to fuel and fire conditions at the point of emission, characterize the conditions relating to plume rise, follow plumes downwind to understand chemical transformation and air quality impacts and assess the efficacy of satellite detections for estimating the emissions from sampled fires. FIREX-QA is a joint venture between NOAA and NASA. This campaign includes 21 flights with a total of 354 flight tracks.

There are 354 data files in Hierarchical Data Format (HDF; *.hdf) format included in this dataset. There are also 480 companion files containing a variety of supplementary information (Table 2); one set of companion files for each flight number.  

Figure 1. Single-band images and an RGB composite image from flight track 08 acquired on 29 July 2019 over the North Hills Fire in Montana, California, USA. Source: companion file 1981715_08.jpg

Citation

Crawford, J.H., C. Warneke, and J.P. Schwarz. 2021. MASTER: Fire Influence on Air Quality (FIREX-AQ), Western-Central USA, Summer 2019. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1941

Table of Contents

  1. Dataset Overview
  2. Data Characteristics
  3. Application and Derivation
  4. Quality Assessment
  5. Data Acquisition, Materials, and Methods
  6. Data Access
  7. References

Dataset Overview

This dataset includes Level 1B (L1B) data products from the MODIS/ASTER Airborne Simulator (MASTER) instrument. The raw data were collected as part of the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) program during 21 flights aboard a NASA DC-8 aircraft over the central and western U.S. from 2019-07-22 to 2019-09-03. The purpose of these flights was to measure emissions and to characterize the aerosols in the smoke plume above and downwind of the fire, and determine the overall spatial extent of wildfires and prescribed fires. Data products include L1B multispectral imagery in 50 bands covering wavelengths of 0.460 to 12.879 micrometers.

The MODIS/ASTER Airborne Simulator (MASTER) is a modified Daedalus Wildfire scanning spectrometer that flies on a variety of multi-altitude research aircraft and provides spectral information similar to that provided by the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), which are aboard two NASA Earth Observing System Satellites, TERRA & AQUA.

The overarching objective of the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) program is to provide measurements of trace gas and aerosol emissions for wildfires and prescribed fires in great detail, relate them to fuel and fire conditions at the point of emission, characterize the conditions relating to plume rise, follow plumes downwind to understand chemical transformation and air quality impacts and assess the efficacy of satellite detections for estimating the emissions from sampled fires. FIREX-QA is a joint venture between NOAA and NASA. This campaign includes 21 flights with a total of 354 flight tracks.

Project: MODIS/ASTER Airborne Simulator

The MODIS/ASTER Airborne Simulator (MASTER) is a scanning spectrometer which flies on a variety of multi-altitude research aircraft and provides data similar to the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). MASTER first flew in 1998 and has ongoing deployments as a Facility Instrument in the NASA Airborne Science Program (ASP). MASTER is a joint project involving the Airborne Sensor Facility (ASF) at the Ames Research Center, the Jet Propulsion Laboratory (JPL), and the Earth Resources Observation and Science Center (EROS).

Related Publication

Hook, S.J. Myers, J.J., Thome, K.J., Fitzgerald, M. and A.B. Kahle. 2001. The MODIS/ASTER airborne simulator (MASTER) - a new instrument for earth science studies. Remote Sensing of Environment 76:93–102. https://doi.org/10.1016/S0034-4257(00)00195-4

Related Datasets

Additional MASTER datasets are available on the ORNL DAAC MASTER project page. 

Acknowledgments

The MASTER instrument is maintained and operated by the Airborne Sensor Facility (ASF) at NASA Ames Research Center in Mountain View, California, under the oversight of the EOS Project Science Office at NASA Goddard. Data processing was conducted at NASA Ames Research Center and the Jet Propulsion Laboratory at the California Institute of Technology in Pasadena, California. FIREX-AQ is a joint venture between NOAA and NASA.

Data Characteristics

Spatial Coverage: Central and western United States

Spatial Resolution: 1 to 20 m

Temporal Coverage: 2019-07-22 to 2019-09-03

Temporal Resolution: One-time estimates

Study Area: Latitude and longitude are given in decimal degrees.

Site Westernmost Longitude Easternmost Longitude Northernmost Latitude Southernmost Latitude
Central and western U.S. -121.506 -83.158 48.577 30.786

Data File Information

There are 354 data files in Hierarchical Data Format (HDF; *.hdf) format included in this dataset. There are also 480 companion files containing a variety of supplementary information (Table 2); one set of companion files for each flight number.  

The HDF files are named MASTERLAA_BBBBBBBB_CC_YYYYMMDD_EEFF_GGHH_V01.hdf (e.g., MASTERL1B_1981712_01_20190722_1946_1949_V01.hdf), where

AA = ”1B”, indicates L1B data level,
BBBBBBBB = flight number (21 flights),
CC = flight track (354 tracks),
YYYYMMDD = date of sampling,
EEFF = starting time at EE hour and FF minute, and
GGHH = ending time at GG hour and HH minute.

A “flight” is a deployment flown on a single day, and a “flight track” refers to a segment of a given flight. Each HDF file corresponds to a flight track, and the number of flight tracks varies among flights (Table 1).

Data File Details

The HDF-4 files contain swath trajectory data using longitude and latitude coordinates. The spatial resolution ranges from 1–20 m and is a function of aircraft altitude.

Table 1. Flight track details for each MASTER flight during the 2020 campaign over central and western U.S.

Date Flight Number Locations (USA) Number of Flight Tracks
2019-07-22 1981712 California / Nevada / Oregon (Ferry to Idaho) 7
2019-07-24 1981713 Idaho (Sheep / Shady Fires) 6
2019-07-25 1981714 Idaho (Shady Fire) 7
2019-07-29 1981715 Montana / California / Oregon (North Hills / Tucker Fires) 19
2019-07-30 1981716 Northwestern USA (North Hills / Tucker / Left Hand Fires) 13
2019-08-02 1981717 Montana / Idaho (Ridgetop / Mica Creek / Lick Creek Fires) 14
2019-08-03 1981718 Idaho / Washington (Lick Creek / Williams Flats Fires) 12
2019-08-06 1981719 Washington / Montana (Williams Flats / Snow Creek / Horsefly Fires) 10
2019-08-07 1981720 Washington / Montana (Williams Flats Fire) 9
2019-08-08 1981721 Washington (Williams Flats Fire) 5
2019-08-12 1981722 Nevada / California / Arizona (Spring / Castle Fires) 14
2019-08-13 1981723 Arizona (Trumbull / Castle Fires) 11
2019-08-15 1981724 Arizona (Sheridan / Saber / Boulin / Trumbull Fires) 14
2019-08-16 1981725 Arizona (Sheridan / Boulin / Ikes / Castle Fires) 7
2019-08-21 1981727 Texas / Louisiana / Mississippi (Ag Fires) 22
2019-08-23 1981728 Mississippi / Louisiana / Arkansas (Ag Fires) 33
2019-08-26 1981729 Oklahoma / Arkansas / Texas / Louisiana (Ag Fires) 25
2019-08-29 1981730 Nebraska / Kansas / Oklahoma (Ag Fires) 19
2019-08-30 1981731 Florida (Prescribed Burn) / Georgia / Alabama (Ag Fires) 34
2019-08-31 1981732 Mississippi / Arkansas / Louisiana (Ag Fires) 38
2019-09-03 1981733 Louisiana / Mississippi / Arkansas / Missouri (Ag Fires) 35

Table 2. Companion file names and descriptions. "BBBBBBB" in the file name designates one of nine flight tracks

File Name Description
BBBBBBB_CC.jpg Browse figures; one per flight track, multiple tracks per flight
BBBBBBBtm.gif Map showing path of flight
BBBBBBB_spectral_band_info.txt Spectral band information for flight
BBBBBBB_spectral_response_table.zip Spectral response tables by band (ZIP archive of 50 TXT files)
BBBBBBB.cfg Instrument configuration information for the flight in text format
BBBBBBB_anc.txt Ancillary information about flight including notes on aircraft platform, mission objective, and data evaluation
BBBBBBB_summary.txt Summary of flight information. Includes time and coordinates for start and end of flight tracks along with the number of scan lines, solar and instrument angles, and aircraft altitude; FTLT = flight track number

Application and Derivation

The primary mission of MASTER is to: (a) collect ASTER-like and MODIS-like land datasets to support the validation of the ASTER and MODIS geophysical retrieval algorithms; (b) collect these datasets at a higher resolution than the spaceborne datasets to permit scaling studies and comparisons with in-situ measurements; and (c) under fly the EOS-AM1 ASTER and MODIS sensors to provide an additional radiometric calibration to assist with in-flight instrument performance characterization. Calibration is particularly important for ASTER where on-board calibration is dependent on a single black body in the TIR and only partial aperture illumination in the VNIR.

A secondary mission of MASTER is to: (a) provide both a backup instrument and backup modules for the current MODIS Airborne simulator, which is committed to a program of atmospheric and oceanic measurements; and (b) provide a wider spectral and dynamic range alternative to the use of the Thematic Mapper (TM) airborne simulator and Thermal Infrared Multispectral Scanner (TIMS) airborne scanners (JPL, 2021b).

MASTER imagery has been used for mapping wildfires and their impacts (Veraverbeke et al., 2011), land cover (Li and Moon, 2004), coral reefs (Capolsini et al., 2003), and urban heat islands (Zhao and Wentz, 2016).

An increasing frequency of wildfires and prescribed burns threaten to impact air quality at local and regional scales (Jaffe et al., 2020) The overarching objective of the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) program is to provide measurements of trace gas and aerosol emissions for wildfires and prescribed fires in great detail, relate them to fuel and fire conditions at the point of emission, characterize the conditions relating to plume rise, follow plumes downwind to understand chemical transformation and air quality impacts, and assess the efficacy of satellite detections for estimating the emissions from sampled fires. Additional data from the FIREX-AQ program are available from http://doi.org/10.5067/SUBORBITAL/FIREXAQ2019/DATA001.

Themes of the FIREX-AQ program

Figure 2. Themes of the FIREX-AQ program. Source: https://csl.noaa.gov/projects/firex-aq/about/

Quality Assessment

The MASTER instrument channels are calibrated spectrally and radiometrically in the laboratory preflight and postflight. The mid-infrared and thermal infrared channels (26–50) are also radiometrically calibrated in-flight by viewing an internal hot and cold blackbody with each scanline (Hook et al., 2001). Three calibration and validation experiments were conducted in 1998–2001 (Hook et al., 2001; JPL, 2021a). Spectral response information for this campaign is available as companion files.

Data Acquisition, Materials, and Methods

The MASTER instrument was developed by the NASA Ames Research Center in conjunction with the Jet Propulsion Laboratory. The instrument consists of three key components: the scanning spectrometer, the digitizer, and the storage system. The scanning unit was built by Sensys Technology (formerly Daedalus Enterprises) and the digitizer was a collaborative effort between Berkeley Camera Engineering and the Ames Airborne Sensor Facility (ASF). The data storage system and overall system integration were also provided by the ASF.

The MASTER instrument is similar to the MODIS Airborne Simulator (developed by the MODIS project (King et al., 1996). However, it has two key differences. First, MASTER supports a variety of scan speeds allowing it to acquire contiguous imagery from a variety of altitudes with different pixel sizes. Second, the channel positions are configured to closely match those of ASTER and MODIS. A detailed description of the instrument and optical system are provided by Hook et al. (2001) and King et al. (1996), respectively.

For this campaign, the MASTER instrument was flown on NASA's DC-8 aircraft at altitudes of 264–12390 m above sea level. Flights targeted active wildfires and prescribed fires to record air quality metrics.

Flight tracks

Figure 3. Flight tracks in this dataset represented as rectangular polygons.

Example flight path from 2019-07-29

Figure 4. A flight path for Flight 1981715, flown on 2019-07-29. Flight 1981715 and 17 flight tracks occurred over Montana, Oregon, and California. Source: companion file 1981715tm.gif

Data Access

These data are available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

MASTER: Fire Influence on Air Quality (FIREX-AQ), Western-Central USA, Summer 2019

Contact for Data Center Access Information:

References

Capolsini, P., S. Andréfouët, C. Rion, and C. Payri. 2003. A comparison of Landsat ETM+, SPOT HRV, Ikonos, ASTER, and airborne MASTER data for coral reef habitat mapping in South Pacific islands. Canadian Journal of Remote Sensing 29:187-200. https://doi.org/10.5589/m02-088

Hook, S.J. Myers, J.J., Thome, K.J., Fitzgerald, M., and A.B. Kahle. 2001. The MODIS/ASTER airborne simulator (MASTER) - a new instrument for earth science studies. Remote Sensing of Environment 76:93-102. https://doi.org/10.1016/S0034-4257(00)00195-4

Jaffe, D.A., S.M. O’Neill, N.K. Larkin, A.L. Holder, D.L. Peterson, J.E. Halofsky, and A.G. Rappold. 2020. Wildfire and prescribed burning impacts on air quality in the United States. Journal of the Air & Waste Management Association 70:583–615. https://doi.org/10.1080/10962247.2020.1749731

JPL. 2021a. Calibration and Validation, MASTER: MODIS/ASTER Airborne Simulator. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA. https://masterprojects.jpl.nasa.gov/cal-val

JPL. 2021b. Science objectives, MASTER: MODIS/ASTER Airborne Simulator. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA. https://masterprojects.jpl.nasa.gov/objectives

King, M.D., W.P. Menzel, P.S. Grant, J.S. Myers, G.T. Arnold, S.E. Platnick, L.E. Gumley, S.C. Tsay, C.C. Moeller, M. Fitzgerald, K.S. Brown, and F.G. Osterwisch. 1996. Airborne scanning spectrometer for remote sensing of cloud, aerosol, water vapor and surface properties. J. Atmospheric and Oceanic Technology 13:777-794. https://doi.org/10.1175/1520-0426(1996)013<0777:ASSFRS>2.0.CO;2

Li, P., and W.M. Moon. 2004. Land cover classification using MODIS-ASTER airborne simulator (MASTER) data and NDVI: A case study of the Kochang area, Korea. Canadian J. Remote Sensing 30:123-126. https://doi.org/10.5589/m03-061

Veraverbeke, S., S. Harris, and S. Hook. 2011. Evaluating spectral indices for burned area discrimination using MODIS/ASTER (MASTER) airborne simulator data. Remote Sensing of Environment 115:2702-2709. https://doi.org/10.1016/j.rse.2011.06.010

Zhao, Q., and E.A. Wentz. 2016. A MODIS/ASTER Airborne Simulator (MASTER) imagery for urban heat island research. Data 1:7. https://doi.org/10.3390/data1010007