Year: 2019
Type: article
Abstract: This study evaluates a new generation of satellite imaging spectrometers to measure point source methane emissions from anthropogenic sources. We used the Airborne Visible and Infrared Imaging Spectrometer Next Generation(AVIRIS-NG) images with known methane plumes to create two simulated satellite products. One simulation had a 30 m spatial resolution with ~200 Signal-to-Noise Ratio (SNR) in the Shortwave Infrared (SWIR) and the other had a 60 m spatial resolution with ~400 SNR in the SWIR; both products had a 7.5 nm spectral spacing. We applied a linear matched filter with a sparsity prior and an albedo correction to detect and quantify the methane emission in the original AVIRIS-NG images and in both satellite simulations. We also calculated an emission flux for all images. We found that all methane plumes were detectable in all satellite simulations. The flux calculations for the simulated satellite images correlated well with the calculated flux for the original AVIRIS-NG images. We also found that coarsening spatial resolution had the largest impact on the sensitivity of the results. These results suggest that methane detection and quantification of point sources will be possible with the next generation of satellite imaging spectrometers.
Source: Remote Sensing
DOI: 10.3390/rs11243054
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $1,824
Awards: ANTHROPOGENIC EMISSIONS OF CARBON DIOXIDE (CO2) AND METHANE (CH4) HAVE RESULTED IN POSITIVE RADIATIVE FORCING AND INCREASED GLOBAL TEMPERATURE. FOR BOTH ATMOSPHERIC TRACE GASES POINT SOURCE EMISSIONS REPRESENT AN IMPORTANT CONTRIBUTION TO TOTAL EMISSIONS. A SMALL NUMBER OF POINT SOURCES CONTRIBUTE A LARGE PERCENTAGE OF POINT SOURCE EMISSIONS WITH EPA DATA POINTING TO LESS THAN 1.5% OF FACILITIES BEING RESPONSIBLE FOR OVER A THIRD OF TOTAL REPORTED POINT SOURCE EMISSIONS IN THE US. UNINTENDED CH4 EMISSIONS KNOWN AS FUGITIVE EMISSIONS HAVE ALSO BEEN SHOWN TO BE REGIONALLY SIGNIFICANT SOURCES. DETECTING AND QUANTIFYING POINT SOURCE EMISSIONS IS CRITICALLY IMPORTANT FOR REDUCING ANTHROPOGENIC GREENHOUSE GAS EMISSIONS BUT CURRENT AND PLANNED SATELLITE MISSIONS FOR RETRIEVING COLUMN CO2 AND CH4 CONCENTRATIONS ARE NOT CAPABLE OF RESOLVING POINT SOURCE EMITTERS. RECENT WORK HAS DEMONSTRATED THAT AIRBORNE VISIBLE INFRARED IMAGING SPECTROMETER-NEXT GENERATION (AVIRIS-NG) DATA ARE CAPABLE OF DETECTING TRACE GAS PLUMES AND EVEN ESTIMATING EMISSION RATES. MATCHED FILTER ALGORITHMS DEVELOPED FOR TRACE GAS PLUME DETECTION HAVE SHOWN SOME SUCCESS BUT THEY IGNORE SPATIAL STRUCTURE IN BACKGROUND REFLECTANCE AND IN THE PLUME ITSELF. TAKING THIS SPATIAL STRUCTURE INTO ACCOUNT WILL REDUCE FALSE POSITIVE PLUME DETECTIONS AND IMPROVE SENSITIVITY TO TRACE GAS ABSORPTION FEATURES IN THE SHORTWAVE INFRARED. THE PRIMARY OBJECTIVE OF THE PROPOSED RESEARCH IS TO DEVELOP NEW ITERATIVE ALGORITHMS FOR CO2 AND CH4 PLUME DETECTION IN AVIRISNG DATA USING DATA COLLECTED DURING THE INDIA CAMPAIGN. THESE ALGORITHMS WILL EXPLICITLY TAKE ADVANTAGE OF SPATIAL CORRELATION IN TRACE GAS CONCENTRATIONS WITHIN PLUMES TO IMPROVE DETECTION APPLYING METHODS DEVELOPED WITHIN THE FIELD OF BIOMEDICAL IMAGE RECONSTRUCTION. THE ALGORITHMS WILL RELY ON MAXIMUM A POSTERIORI (MAP) PARAMETRIC ESTIMATION AND MARKOV RANDOM FIELD MODELING TO ESTIMATE TRACE GAS MIXING RATIO LENGTH THE PRODUCT OF CONCENTRATION AND PATH LENGTH. TEMPLATE SPECTRA REQUIRED FOR DETECTION WILL BE GENERATED BY RADIATIVE TRANSFER MODELING., G4496622097
OpenAlex ID: W2996742363