Fig 1.
Map of Ghana, West Africa (green shaded region in West Africa) with the rain gauge network shown as circles on the right panel. The study region is demarcated into four agro-ecological zones as per Ghana Meteorological Agency (GMet) standards [41]. The four study locations (Bole, Kumasi, Accra, and Axim) for thunderstorm case assessments are represented by green circles on the right panel.
Fig 2.
Frequency distribution OF CAPE AND LIS.
Mean monthly climatology distribution of CAPE (a) and Lightning flash rate density over West Africa (1998–2012).
Fig 3.
Seasonal distribution of CAPE and LIS.
A seasonal distribution plot CAPE and Lightning flash rate density (FRD). Note that the color bar used in these plots are for density distribution for both variables over West Africa (1998–2012).
Fig 4.
Seasonal hexagonal bin plot of CAPE and Lifted index to LIS occurrence.
A seasonal hexagonal bin plot of CAPE and Lifted index with respect to lightning flash rate density over West Africa (1998–2012).
Fig 5.
Seasonal hexagonal bin plot of CAPE and relative humidity.
A seasonal hexagonal bin plot of CAPE and Relative humidity (at 200 hPa, 500 hPa and 925 hPa) with respect to Lightning flash rate density over West Africa (1998–2012).
Fig 6.
Occurrence of lightning flash rate density under CAPE and CIN (West Africa).
Hexbin plot of lightning flash rate density for the combination of CAPE and CIN over West Africa (1998–2012).
Fig 7.
Lightning flash rate density under CAPE and LI (West African Zones).
Zonal Hexbin plot of Lightning flash rate density for the combination of CAPE and LI over West Africa (1998–2012). Note that the values for fL are directly proportional to the frequency of lightning.
Fig 8.
Lightning flash rate density under RH and CAPE (West African Zones).
Zonal hexbin plot of Lightning flash rate density for the combination of RH and CAPE over West Africa (1998–2012). Note that the values for fL are directly proportional to the frequency of lightning.
Fig 9.
Lightning flash rate density under 2m temperature and convective rainfall (West African Zones).
Zonal hexbin plot of Lightning flash rate density for the combination of 2m temperature and convective rainfall over West Africa (1998–2012). Note that the values for fL are directly proportional to the frequency of lightning.
Fig 10.
Mean monthly FRD Climatology over West Africa.
Mean monthly FRD Climatology over West Africa, January (a) to December (l) in progressive order (1998–2012).
Fig 11.
Mean monthly CAPE Climatology over West Africa.
Mean monthly CAPE Climatology over West Africa (1998–2012), with similar description as Fig 10.
Fig 12.
Seasonal Mean Flash Rate Density Climatology over West Africa.
Seasonal Mean LIS Flash Rate Density Climatology over West Africa, December -January -February (DJF) to September-October-November (SON) in progressive order (1998–2012).
Fig 13.
Seasonal RH Climatology over West Africa (1998–2012).
Seasonal RH Climatology over West Africa (1998–2012), with similar description as Figs 10 and 12 at 200 hPa, 500 hPa, 925 hPa.
Fig 14.
Seasonal Lifted Index Climatology over West Africa.
Seasonal Lifted Index Climatology over West Africa (1998–2012), with similar description as Figs 10 and 12.
Fig 15.
Storm frequency and trends over Accra, Axim, Bole and Kumasi.
The Storm frequency, monthly and annual trend of TS activities in Accra, Axim, Bole and Kumasi.
Fig 16.
Boxplot of TS and Dry TS frequency.
Boxplot of TS and Dry TS frequency over four stations (Accra, Axim, Bole, Kumasi). Solid lines within the boxes represent medians. Upper and lower values of boxes indicate 75th and 25th percentile; upper and lower whiskers 90th and 10th percentiles.
Table 1.
The r-values and p-values between convective rainfall amount and Lightning flash rate density over the various agro-climatic zones.
P-values above 0.05 indicate low/no significant correlation between the two variables.
Table 2.
The r-values and p-values between lightning flash rate density (FRD), convective available potential energy (CAPE), lifted index (LI) and relative humidity (RH) over the study area.
P-values above 0.05 indicate low/no significant correlation between the two variables.
Table 3.
The monthly mean values for convective available potential energy (CAPE) and Lightning flash rate density (FRD) over West Africa.
Fig 17.
Seasonal climatology of lightning over Ghana Mean seasonal FRD Climatology over Ghana, December -January -February (DJF) to September-October-November (SON) in progressive order (1998–2012).
Fig 18.
Mean seasonal rainfall climatology over Ghana Mean seasonal rainfall climatology over Ghana, December -January -February (DJF) to September-October-November (SON) in progressive order (1998–2012).
Fig 19.
Monthly Mean FRD Climatology over Ghana Monthly Mean FRD Climatology over Ghana, January (a) to December (l) in progressive order (1998–2012).
Fig 20.
Monthly Rainfall Climatology over Ghana Monthly Rainfall Climatology over Ghana (1998–2012), with similar description as Fig 19.