Cloud-to-ground lightning characteristics in Yunnan province from 2006 to 2010

Abstract

Cloud-to-ground lightning data have been analyzed for the years 2006-2010 for Yunnan province for all ground flashes, positive flashes, the percentage of positive lightning, and peak currents for negative and positive lightning. Mean 400 thousands cloud-to-ground flashes happen in Yunnan province every year. The highest flash densities are in the Central Yunnan province (6.4 fl· km <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> yr <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> ), Areas of greater than 50% positive lightning occur in the west river valley. The median negative peak current is 27.9kA. The median positive peak current is 47.4 kA. It is founded that substantial differences between wet season lightning (Apr-Sep) and dry season lightning (Oct-Mar). Wet season lightning is characterized by a high CG flash count and percent positive CG flashes less than 5%; dry season lightning is characterized by a low CG flash count and percent positive CG flashes greater than 20%. The most of CG lightning flashes is single return stroke. The CG lightning activity in Yunnan province is weak in the morning and increases rapidly in the afternoon.