ENVI provides the following gas indices:

Methane Index

This index detects concentrated sources of CH4 emissions based on the absorption of CH4 in the shortwave infrared (SWIR) region.

The Methane Index needs to use radiance data, not reflectance data.

Reference: Xiao, C, B. Fu, H. Shiu, Z. Guo, and J. Zhu. "Detecting the Sources of Methane Emission from Oil Shale Mining and Processing Using Airborne Hyperspectral Data." Remote Sensing 12, No. 3 (2020): 537.

Methane Index for AVIRIS

This index uses AVIRIS-CL bands to detect concentrated sources of CH4 emissions based on the absorption of CH4 in the shortwave infrared (SWIR) region. This methane formula was originally designed for use with AVIRIS bands. However, it will work with any multispectral sensor with a similar band range.

The Methane Index for AVIRIS needs to use radiance data, not reflectance data.

This methane index is based on the index described in the following publication. It has been modified by NV5 Geospatial Solutions, Inc. for use in ENVI.

Reference

Scafutto, R. Werff, H. Bakker, W. Meer, F. and Filho, C. "An Evaluation of Airborne SWIR imaging spectrometers for CH4 mapping: Implications of band positioning, spectral sampling noise." International Journal of Applied Earth Observation and Geoinformation 94, (2021):102233.

Methane Index for AVIRIS-NG

This index uses AVIRIS-NG bands to detect concentrated sources of CH4 emissions based on the absorption of CH4 in the shortwave infrared (SWIR) region. This methane formula was originally designed for use with AVIRIS-NG bands. However, it will work with any multispectral sensor with a similar band range.

The Methane Index for AVIRIS-NG needs to use radiance data, not reflectance data.

This methane index is based on the index described in the following publication. It has been modified by NV5 Geospatial Solutions, Inc. for use in ENVI.

Reference

Scafutto, R. Werff, H. Bakker, W. Meer, F. and Filho, C. "An Evaluation of Airborne SWIR imaging spectrometers for CH4 mapping: Implications of band positioning, spectral sampling noise." International Journal of Applied Earth Observation and Geoinformation 94, (2021):102233.

Methane Index for EMIT

This index uses EMIT bands to detect concentrated sources of CH4 emissions based on the absorption of CH4 in the shortwave infrared (SWIR) region. This methane formula was originally designed for use with EMIT bands. However, it will work with any multispectral sensor with a similar band range.

The Methane Index for EMIT needs to use radiance data, not reflectance data.

This methane index is based on the index described in the following publication. It has been modified by NV5 Geospatial Solutions, Inc. for use in ENVI.

Reference

Scafutto, R. Werff, H. Bakker, W. Meer, F. and Filho, C. "An Evaluation of Airborne SWIR imaging spectrometers for CH4 mapping: Implications of band positioning, spectral sampling noise." International Journal of Applied Earth Observation and Geoinformation 94, (2021):102233.

Methane Index for ENMAP

This index uses EnMAP bands to detect concentrated sources of CH4 emissions based on the absorption of CH4 in the shortwave infrared (SWIR) region. This methane formula was originally designed for use with EnMAP bands. However, it will work with any multispectral sensor with a similar band range.

The Methane Index for ENMAP needs to use radiance data, not reflectance data.

This methane index is based on the index described in the following publication. It has been modified by NV5 Geospatial Solutions, Inc. for use in ENVI.

Reference

Scafutto, R. Werff, H. Bakker, W. Meer, F. and Filho, C. "An Evaluation of Airborne SWIR imaging spectrometers for CH4 mapping: Implications of band positioning, spectral sampling noise." International Journal of Applied Earth Observation and Geoinformation 94, (2021):102233.

Methane Index for PRISMA

This index uses PRISMA bands to detect concentrated sources of CH4 emissions based on the absorption of CH4 in the shortwave infrared (SWIR) region. This methane formula was originally designed for use with PRISMA bands. However, it will work with any multispectral sensor with a similar band range.

The Methane Index for PRISMA needs to use radiance data, not reflectance data.

This methane index is based on the index described in the following publication. It has been modified by NV5 Geospatial Solutions, Inc. for use in ENVI.

Reference

Scafutto, R. Werff, H. Bakker, W. Meer, F. and Filho, C. "An Evaluation of Airborne SWIR imaging spectrometers for CH4 mapping: Implications of band positioning, spectral sampling noise." International Journal of Applied Earth Observation and Geoinformation 94, (2021):102233.