@ARTICLE{10.21494/ISTE.OP.2022.0898, TITLE={An accurate estimation of the radiative forcing by the Monte-Carlo method}, AUTHOR={Yaniss Nyffenegger-Péré, Mégane Bati, Stéphane Blanco, Jean-Louis Dufresne, Mouna El Hafi, Vincent Eymet, Vincent Forest, Richard Fournier, Nicolas Mellado, Nada Mourtaday, Mathias Paulin, }, JOURNAL={Entropy: Thermodynamics – Energy – Environment – Economy }, VOLUME={3}, NUMBER={Special issue}, YEAR={2022}, URL={https://www.openscience.fr/An-accurate-estimation-of-the-radiative-forcing-by-the-Monte-Carlo-method}, DOI={10.21494/ISTE.OP.2022.0898}, ISSN={2634-1476}, ABSTRACT={We want to estimate the outgoing Earth’s radiative flux integrated over the thermal infrared, over the entire surface of the globe and over a long climatic period. This calculation is known to be very difficult to achieve without simplifications of the frequency, spatial or temporal description (e.g. switching from a line-by-line model to a band model, using a coarser temporal discretization, etc). We show that the Monte-Carlo method can avoid these simplifications if we combine the following two ideas : introduce fictitious colliders to allow ray tracing without knowledge of the extinction coefficient field and statistically sample the spectral lines. We show that it is not more expensive to perform this integration over a day or a month, over an atmospheric column or over the whole Earth, or finally over a narrow frequency band or over the whole infrared spectrum.}}