AUTHOR=Wang Yong , Zhang Maolei , Wang Jiapeng , Wang Gang , Cui Ruyue , Dong Lei , Wu Hongpeng TITLE=Field measurement of atmospheric CO₂ column abundance based on portable laser heterodyne radiometer JOURNAL=Frontiers in Physics VOLUME=13 YEAR=2025 URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2025.1553252 DOI=10.3389/fphy.2025.1553252 ISSN=2296-424X