Clouds play essential roles in the Earth’s radiative energy balance and global hydrological cycle. Aerosols, the particles suspended in the air, can change cloud properties by interacting with radiation or serving as cloud condensation nuclei. However, the variations in cloud properties subjected to aerosol context, and their impacts on radiation and precipitation, are related to many complicating factors such as land types, meteorological conditions, cloud types, aerosol properties, and their co-varied relationships. Complication of cloud-aerosol-radiation-precipitation interactions makes representation of clouds one of the largest uncertainties in climate models for future climate prediction. It has also become a prevailing topic in atmospheric sciences over the past several decades.
Significant efforts have been made in China during the past 20 years in understanding cloud physics, aerosol hygroscopic growth, cloud in-situ measurements and remote sensing observations, human weather modifications, and aerosol-cloud-radiation-precipitation interactions (CARPI). Progress in CARPI highly depends on the development of new observation techniques and advancement of numerical models. Over the past 20 years, substantial progress has been made towards developing cloud remote sensing instruments and platforms, data processing algorithms, and weather and climate models. For example, high-quality aircraft with advanced world-standard instruments have been deployed. New satellites with more instruments, having more radiometric channels and higher sensitivity, also have been launched. Retrieval algorithms and numerical weather and climate simulation models with performance comparable to global models have been developed. State-of-the-art machine learning techniques have been applied. On the one hand, these new developments enable scientists to better examine the aerosol-cloud-radiation-precipitation interactions. On the other hand, new challenges emerge rapidly.
Motivated by those facts, we organized the special issue “Cloud-aerosol-radiation-precipitation interaction: progress and challenges” to recap new advances in cloud observation instruments and model development. The purpose is to share with the meteorological community the progress made in characterizing cloud properties, cloud processes and radiative impacts, the progress achieved in recognizing weather and climate model performance and simulations, and the challenges existing at the current time. Our special issue has solicited 16 articles, covering the following four research topics.
New Progress and Challenges in Cloud–Aerosol–Radiation–Precipitation Interactions: Preface for a Special Issue