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MASTER: Western Diversity Time Series Campaign, WDTS, California, USA, Fall 2020

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 Western Diversity Time Series (WDTS, formerly HyspIRI) program during nine flights aboard a NASA ER-2 aircraft over selected areas of California, USA, from 2020-09-17 to 2020-10-15. Data products include L1B multispectral imagery in 50 bands covering wavelengths of 0.460 to 12.879 micrometers. The WDTS program will observe California's ecosystems and provide critical information on natural disasters such as volcanoes, wildfires, and drought. MASTER products can identify vegetation type and health and provide a benchmark for the state of the ecosystems against which future changes can be assessed.

The MASTER instrument 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 and Aqua. The primary goal of this airborne campaign was to demonstrate important science and applications research that is uniquely enabled by the full suite of MASTER thermal infrared bands as well as the contiguous spectroscopic measurements of the AVIRIS (also flown in similar campaigns), or combinations of measurements from both instruments.

There are 90 data files in Hierarchical Data Format (HDF; *.hdf) format included in this dataset. There are also 144 companion files containing a variety of supplementary information (Table 1).

Figure 1. Single-band images and an RGB composite image from flight track 09 acquired on 15 October 2020 near Yosemite National Park, California, USA. Source: companion file 2190600_09.jpg

Citation

Hook, S.J., and R.O. Green. 2021. MASTER: Western Diversity Time Series Campaign, WDTS, California, USA, Fall 2020. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1940

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 Western Diversity Time Series (WDTS, formerly HyspIRI) program during nine flights aboard a NASA ER-2 aircraft over selected areas of California, U.S., from 2020-09-17 to 2020-10-15. Data products include L1B multispectral imagery in 50 bands covering wavelengths of 0.460 to 12.879 micrometers. The WDTS program will observe California's ecosystems and provide critical information on natural disasters such as volcanoes, wildfires, and drought. MASTER products can identify vegetation type and health and provide a benchmark for the state of the ecosystems against which future changes can be assessed.

The MASTER instrument 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 and Aqua. The primary goal of this airborne campaign was to demonstrate important science and applications research that is uniquely enabled the full suite of MASTER thermal infrared bands as well as the contiguous spectroscopic measurements of the AVIRIS (also flown in similar campaigns), or combinations of measurements from both instruments.

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 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.

Data Characteristics

Spatial Coverage: Portions of California, USA

Spatial Resolution: 50 m

Temporal Coverage: 2020-09-17 to 2020-10-15

Temporal Resolution: One-time estimate

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

Site Northernmost Latitude Southernmost Latitude Easternmost Longitude Westernmost Longitude
Portions of California, USA -123.738 -114.743 39.634 32.594

Data File Information

There are 90 data files in Hierarchical Data Format (HDF; *.hdf) format included in this dataset. There are also 144 companion files containing a variety of supplementary information (Table 2).  

The HDF files are named as MASTERLAA_BBBBBBB_CC_YYYYMMDD_EEFF_GGHH_V01.hdf (e.g., MASTERL1B_2190600_12_20201015_2119_2152_V01.hdf), where

 AA = ”1B”, indicates L1B data level,
BBBBBBB = flight number (nine flights),
CC = flight track (86 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 files contain swath trajectory data using longitude and latitude coordinates. The spatial resolution ranges from 44–50 m and is a function of aircraft altitude.

Table 1. Flight track details for each MASTER flight during the 2020 campaign over California, U.S.

Date Flight Number Locations Number of Flight Tracks
2020-09-17 2095500 Salton Sea / Bobcat Fire, CA 7
2020-09-24 2095600 Lake Tahoe / Soda Straw / Creek Fire, CA 14
2020-09-25 2095700 Soda Straw / Creek Fire, CA 1
2020-09-30 2095800 Soda Straw / Creek Fire / Santa Barbara, CA 12
2020-10-05 2190100 Ivanpah / Mt. Pass, CA 11
2020-10-06 2190200 Ivanpah / Mt. Pass, CA 10
2020-10-07 2190300 Southern California / Bobcat Fire 10
2020-10-13 2190500 San Francisco Bay Area / Soda Straw / Creek Fire, CA 13
2020-10-15 2190600 Yosemite / Soda Straw / Creek Fire, CA 12

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).

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.

The Western Diversity Time Series (WDTS, formerly HyspIRI) program will observe California’s ecosystems and provide critical information on natural disasters such as volcanoes, wildfires, and drought. It will provide a benchmark on the state of the ecosystems against which future changes can be assessed, as the instruments will be capable of identifying vegetation type and health. The WDTS Airborne Campaign is a multi-year effort to collect seasonal VIS-SWIR and TIR airborne scanner data using both AVIRIS and MASTER remote sensing instruments aboard the ER-2 high-altitude platform (ASF, 2021).

For this campaign, the MASTER instrument was flown on NASA's ER-2 aircraft at altitudes of 19,080–20,220 m above sea level.

Flight tracks

Figure 2. Flight tracks over California, Arizona, and Nevada represented as rectangular polygons.

Typical flight path

Figure 3. Typical flight path is shown for 2020-10-15. Flight 2190600 and 12 flight tracks. Source: companion file 2190600tm.gif

Data Access

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

MASTER: Western Diversity Time Series Campaign, WDTS, California, USA, Fall 2020

Contact for Data Center Access Information:

References

ASF. 2021. Campaign summary information: HyspIRI / WDTS Airborne Campaign. Airborne Sensor Facility, Airborne Science Program, NASA Ames Research Center, Moffett Field, California. https://asapdata.arc.nasa.gov/sensors/master/data/deploy_html/hyspiri_home.html

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

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