Analysis of Meteorological Measurements made over Three Rainy Seasons and Rainfall Simulations in Sinazongwe District, Southern Province, Zambia

Abstract

Zambia has frequently been affected by abnormal weather and droughts. Our research focused on the type of meteorological data required to assist farmers' efforts to avoid the risks associated with these weather conditions. We conducted local meteorological observations from September 2007 to August 2010 at three sites in Sinazongwe District, Zambia. The three rainy seasons of this period coincided in sequence with La Niña (normal) and El Niño conditions. The mean annual precipitation for the three years of our study exceeded 1200 mm, which was considerably more than the regional annual average rainfall from 1970 to 2000 of around 800 mm per year. We used detailed analyses of intraseasonal variations in other meteorological elements to attempt to explain the high precipitation. Local circulation dominated in our research area, while heavy rain induced by convection in the afternoon and night might account for precipitation exceeding the norm. We numerically simulated meteorological conditions over the past decade to determine whether the annual precipitation

Sensitivity of Simulations of Zambian Heavy Rainfall Events to the Atmospheric Boundary Layer Schemes

“…The role of surface heating is indicated by the lag of about 2 to 4 h between the peak in temperatures and the peak in area average rainfall. Kanno et al [18] also found a strong diurnal cycle in the rainfall of Zambia, indicating strong afternoon convection, and large spatial differences in sites that they studied due to differences in topography.…”

“…Our study also points to a clear need for more ground observations that would greatly assist studies on the performances of different model configurations, not least because the reanalysis and satellite estimates gave some contrasting results. Kanno et al [18] also concluded that the existing meteorological stations were too sparse to use for local meteorological studies. In their situational analysis Venäläinen et al [4] recommended an increase in the number of ground observations and procurement of a radar system and a lightning detection system for ZMD.…”

“…Kanno et al [18] found that the location of the ITCZ resulted in large intra-seasonal variations in three summer seasons that they studied over southern Zambia (from 2007/2008 to 2009/2010). The El Niño Southern Oscillation (ENSO) has also been found to impact the rainfall season of Zambia, with cool ENSO events being associated with increased rainfall [36].…”

“…The availability of an HPC system in Zambia provides an opportunity for ZMD to conduct NWP research to understand atmospheric processes, and to also determine a suitable configuration for simulating weather and climate in Zambia [17]. Kanno et al [18] did a 10 year climate simulation with WRF version 3.2 and found the model overestimated rainfall on three sites in the southern province of Zambia. The representations of subgrid processes such as clouds and turbulence are thought to be responsible for much of the uncertainty in weather and climate simulations [19].…”

Climate Change and Food Security: The Impact of Some Key Variables on Wheat Yield in Kazakhstan

“…In Africa, crop yields have been shown to correlate with ENSO events with El Niño having a negative impact on millet and a positive impact on maize and sorghum production with an indirect effect on temperature and rainfall during the short planting period in the Sahel [30]. Warm ENSO events in east Africa were found to coincide with drier conditions affecting surface temperatures and the Normalized Difference Vegetation Index (NDVI), while Pacific SST anomalies tend to affect air temperature in east Africa, according to Plisnier et al [31], ENSO has been shown to be responsible for variations in temperature, wind, and humidity in Zambia, with three rainy seasons corresponding to La Niña, normal, and El Niño conditions [32].…”