Retrieval of the charge sources neutralized by negative cloud-to-ground lightning flashes in the Daxing’anling Forest region

Using the data from slow and fast antenna network of the 7 stations synchronized by UPS in the Daxing'anling Forest region on July 14,2010,the magnitude and location of charge neutralized by return strokes and continuing currents of negative cloud-to-ground lightning flashes are fitted.The charge lowered by the discrete negative return stroke ranged from 0.1 to 5.0 C with an arithmetic mean of 1.0 C.The charge transported by continuing current processes was from 0.4 to 7.3 C with an arithmetic mean of 3.8 C,and the corresponding average current was from 4.9 to 50.8 A with an arithmetic mean of 25.3 A.The total charge neutralized by a negative flash was in a range from 1.4 to 12.4 C with an arithmetic mean of 6.4 C.The charge neutralized by return strokes and continuing currents gradually raised up from 5.0 km to 10.5 km during the early-mature stage of thunderstorm.When the thunderstorm evolved into the late-mature stage, the average height of charge sources desccndcd from 9.0 to 6.0 km,corresponding to the ambient temperature of about -10℃ to -25℃.The superposition of the neutralized charge and radar echo shows the charge sources of negative cloud-to-ground mainly concentrated inside the cloud region with radar reflectivity higher than 40 dBz.