Fig. 3From: Characteristics of the atmospheric electric field and correlation with CO2 at a rural site in southern BalkansMean diurnal variation of fair weather (FW)–potential gradient (PG) and all weather (AW)–PG for the period of June 2011 to May 2012. Error bars denote standard errors for each hour. Upward and downward arrows denote mean sunrise and sunset time, respectivelyBack to article page