# Review of Satellite Remote Sensing of Carbon Dioxide Inversion and Assimilation
## 3 Carbon Satellite Remote Sensing Inversion Techniques
### Orthogonal Modelling and Inversion Principles
#### 3.1.2 Selection of Forward Modelling
It is applied to limb, sky, and occultation observation modes and contains solar spectral data, absorption cross-section data of various atmospheric components, and vertical profile data of atmospheric trace components, as well as aerosol and surface albedo data. However, the range of bands it supports is only 175.44\(\sim\)2400 nm covered by SCIMACHY. LBLRTM: LBLRTM v12.1 is an atmospheric radiative transfer model developed by Lawrence Berkeley National Laboratory, based on FASCODE developed by the US Air Force Phillips Laboratory, with improved design and higher computational accuracy. LBLRTM is capable of handling a wide range of gases and aerosols, taking into account atmospheric absorption, scattering, and transmission, and is widely used in the fields of atmospheric chemistry and remote sensing. The LBLRTM radiative transfer software package includes LNFL, a tool for atmospheric spectral line parameterization, and LBLRTM, the radiative transfer calculation component, as documented in Figure 12.  
VLIDORT: It is used to simulate the transport process of solar radiation in the atmosphere by vector radiative transfer model based on the discrete coordinate method. Rayleigh scattering of molecules is simple in form and can be calculated directly and accurately by the formulae, which are developed based on the LIDORT radiative transfer model. DISORT: DISORT is an atmospheric radiative transfer model developed at the University of Illinois at Urbana-Champaign, IL, USA. The main features of DISORT are high computational speed and accuracy, its ability to deal with multi-layer atmospheres and multiple gases, and wavelength coverage ranging from UV to microwave, which includes the  
Figure 12: Schematic diagram of the LBLRTM calculation process. physical processes of absorption, scattering, and thermal radiation, as well as bi-directional reflections and emissions at the lower boundary. RTTOV: RTTOV is a fast radiative transfer model developed and more widely used based on the radiative transfer model of the European Centre for Medium-Range Numerical Weather Forecasts (ECMWF) simulation of the TOVS satellite observations. RTTOV is mainly characterized by high accuracy, fast computation speed, and its ability to deal with a wide range of gases and clouds, and it has been applied to the inversion process of the thermal infrared wavelengths of the satellite CO\({}_{2}\) gases. LINTRAN: LINTRAN v2.0 is a linearised vector radiative transfer forward model used in famous algorithm RemoTAP, employing forward-adjoint theory, that is capable of modelling cloud contaminated satellite observations and their derivatives with respect to the state of the atmosphere and the Earth's surface in a numerically efficient manner. Compared to LINTRAN v1.0, v2.0 improves efficiency by combining an iterative solving method with forward-adjoint perturbation theory and separating the first N orders of scattering from the diffuse intensity vector field. LINTRAN is instrumental in analyzing spectral features for identifying and quantifying atmospheric trace gases. Table 4 displays the common radiative transfer models.