Quantitative Applications of Weather Satellite Data for Nowcasting:Progress and Challenges

Monitoring and predicting highly localized weather events over a very short-term period,typically ranging from minutes to a few hours,are very important for decision makers and public action.Nowcasting these events usually relies on radar observations through monitoring and extrapolation.With advanced high-resolution imaging and sounding observations from weather satellites,nowcasting can be enhanced by combining radar,satellite,and other data,while quantitative applications of those data for nowcasting are advanced through using machine learning techniques.Those applications include monitoring the location,impact area,intensity,water vapor,atmospheric instability,precipitation,physical properties,and optical properties of the severe storm at different stages(pre-convection,initiation,development,and decaying),identification of storm types(wind,snow,hail,etc.),and predicting the occurrence and evolution of the storm.Satellite observations can provide information on the environmental characteristics in the preconvection stage and are very useful for situational awareness and storm warning.This paper provides an overview of recent progress on quantitative applications of satellite data in nowcasting and its challenges,and future perspectives are also addressed and discussed.

Ecological Assessment of Oxygen Balance:A Case Study of China’s Natural Oxygen Bars

Ecological assessment plays a vital role in sustainable development of the environment,and thus exploration of specific and integrated ecological assessment methods has become a critical task.In this study,based on the concept of oxygen balance and by accommodating both natural factors and socioeconomic elements,we establish an oxygen(O_(2))balance index(OBI),i.e.,the ratio of the O_(2)production from the ecosystem to the O_(2)consumption by human behavior,based on the net primary productivity(NPP),fuel consumption,gross domestic production(GDP),population data,and so on.The results show that the spatial distributions of OBI in China are intimately correlated to the regional vegetation and socioeconomic development.The estimated OBI values are then validated by statistical data from 27 counties in China,and it is found that the OBI reflects the ecological environment status well.Moreover,the average OBI values derived from 190 natural oxygen bars in China reveal extreme imbalance between O_(2)production and consumption in highly developed regions,especially in the cities,in contrast to good O_(2)balance in areas with high-quality ecological status and less industrialization.The findings from this study have quantitatively captured the regional ecological quality,providing guidance for sustainable natural and socioeconomic developments in local areas of China.