Remote sensing of atmospheric aerosol composition and species Preface List of acronyms 1. Introduction: 1.1. Background; 1.2. Principles; 1.3. Historic perspective and recent advancement 2. Mechanism of aerosol composition remote sensing: 2.1. Optical absorbing components; 2.2. Optical scattering components; 2.3. Mixing rules; 2.4. Aerosol composition model 3. Methodology of aerosol composition remote sensing: 3.1. Retrieval theory; 3.2. Forward modeling; 3.3. Retrieval scheme 4. Applications: 4.1. Inter comparison with in situ measurements; 4.2. Ground based remote sensing; 4.3. Satellite remote sensing Acknowledgments References This Spotlight presents the state of the art of aerosol remote sensing including remote sensing principles and satellite and ground based approaches. The mechanism and theories are introduced along with the component mixing rules e.g. Maxwell Garnett Bruggeman and volume weighted average approaches. Recent advances in aerosol component methods are discussed focusing on composition schemes inversion methods and validation results. The final section looks at the remote sensing applications of atmospheric aerosol composition and species