Development of the Chinese Dual Auroral Radar Network and Preliminary Results.

Led by the National Space Science Center of the Chinese Academy of Sciences, we have built a Chinese dual auroral radar network in northern China, which is called the CN‐DARN. The CN‐DARN consists of three pairs of high‐frequency coherent scattering radar facilities and is one of the key parts of the Chinese Meridian Project Phase II. It has been fully constructed and started trial operations at the end of 2023. The detection range of the radar network extends longitudinally over approximately 9 hr of local times and covers the middle to high latitudes of the entire Asia region above 40° ${}^{\circ}$. In this paper, we present the basic design of the CN‐DARN and its preliminary observations of ionospheric irregularities, subauroral polarization streams (SAPSs) and traveling ionospheric disturbances (TIDs). We also investigate its contribution to the ionospheric convection pattern of the Northern Hemisphere derived from Super Dual Auroral Radar Network (SuperDARN) observations. The results indicate that the CN‐DARN provides excellent measurements and better specifications of flows in the Asian sector, improving our understanding of the global‐scale ionospheric convection pattern in the Northern Hemisphere. These encouraging results lead us to believe that the CN‐DARN will play an important role in studies on the evolution of ionospheric irregularities, the characteristics and evolution of SAPSs, the propagation of TIDs, and global‐scale ionospheric convection dynamics. Plain Language Summary: The ionosphere is home to all charged particles in the Earths atmosphere, and it is also home to many satellites, including space stations. The density of the charged particles is uneven. There are different scales of electron density irregularities in the ionosphere and they can disrupt signals. To monitor the ionospheric environment of the mid‐ and high‐ latitude regions of Asia, three pairs of high‐frequency coherent scattering radars have been deployed in northern China. This network of radars is called the CN‐DARN, short for the Chinese Dual Auroral Radar Network. The CN‐DARN achieves large‐scale continuous detection of the movement of decameter‐scale ionospheric irregularities in the middle and high latitudes of the Asian sector. The detection range can reach 4,000 km from south to north and extends longitudinally over 9 hr of local time. We describe the basic design and parameters of the radar network and present the preliminary observation results obtained during trial operations. The observations results show that the CN‐DARN can monitor ionosphere disturbances effectively over this region; moreover, the observations can be combined with those in the Western Hemisphere to create a comprehensive picture of large‐scale features in geospace. Key Points: The Chinese Dual Auroral Radar Network (CN‐DARN) consists of three pairs of newly constructed radar facilities in northern ChinaThis paper details the hardware, key parameters and preliminary detection results of the CN‐DARNThe CN‐DARN achieves continuous detection of the mid‐ and high‐latitude ionosphere in Asia [ABSTRACT FROM AUTHOR]