A review of research on remote sensing monitoring of rice methane emissions

Rice methane emissions are an important source of agricultural methane emissions, and timely and accurate estimation of rice methane emissions can provide valuable information for policymakers. The data sources, methods, and uncertainties of remote sensing monitoring of rice methane emissions, as well as its current status of development and future outlook, were summarized by means of conceptual analysis and literature research. The results show that remote sensing technology is largely promising for rice methane emission monitoring. It can not only directly monitor rice methane emissions through top-down methods but also indirectly estimate rice methane emissions by combining them with bottom-up methods. However, how to improve the accuracy of top-down and bottom-up methods and narrow the differences between the two types of methods is the key issue that needs to be addressed. In the future, new remote sensing technologies and sensors with better performance can provide additional assurance for accurate estimation of rice methane emissions. The fusion of remote sensing data from multiple sources and the combination of top-down and bottom-up methods are important research directions for quantifying the uncertainty of remote sensing monitoring of rice methane emissions.