A Study on the Application of Mass Smartphone Barometer Data in a Severe Convective Weather in China

In the age of massive data accumulation, crowdsourcing data has gradually become one of the most important data to improve weather forecasting, while the popularity and develpment of smartphones have made it an important source of crowdsourcing data. Almost every smartphone is able to capture the local surface pressure in real time. MOJI is the largest weather app service provider all over the world, with over 500 million users woldwide and over 50 million active users getting weather informations through our APP every day. Thus, we have more than tens of millions data per day. A joint study we conducted with Peking University shows that the data of smartphone barometers are well consistent with the ground-based observation data after some quality control. In addition, before the occurrence of severe convective weather, the data volume of the phone barometer increased rapidly, which has a strong correlation with the severe convective weather, and it can catch the changes of the weather acutely. On this basis, we carry on the further research from two aspects to explore the use of the phone barometer data. On the one hand, the processed phone barometer data were used to carry out the assimilation test with different resolution for a severe convective weather in Beijing area. The results show that after the weather can be better described after the assimilation of phone barometer data and the weather intensity is enhanced significantly, and the weather situation and development are very consistent with the assimilation of the conventional observation data. On the other hand, we will consider using machine learning method to eliminate systematic errors in data to get a greater extent. In this way, the data could be used to our nowcasting which is also based on machine learning. After this it also can be used as real-time data of user’s position in MOJI APP, so that the user can see more accurate and real-time data.