AN INVESTIGATION OF DRY SPELLS OCCURRENCE IN ZOMBA DISTRICT FOR AGRICULTURAL APPLICATION

The threat of accelerating climate variability impacts on species and the future are subjects of growing scientific interest. These variabilities are causing harmful effects on agricultural production around the world including Malawi because of its low adaptive capacity. This study investigated the occurrence and impacts of dry spells on maize production in Zomba District in Malawi. Specifically, the study examines the trends in consecutive dry days (CDD) during January and February when the maize development is critical, alongside the temperature and rainfall data for planting and growth season (November to February). A dry day was defined as a day with less than 1mm of rainfall while for investigating dry spells we used the threshold of at least 7 consecutive dry days. Quality control and cleaning was done on the data set using Jupyterlab and Microsoft excel to determine the frequency of dry spell occurrence, assessment of its impact on maize production and the development of statistical predictive models. Mann-Kendall trend analysis showed no statistically significant trends in consecutive dry days (CDD) during January and February over the study period (2009–2023) as well as in rainfall and temperature, though notable inter-annual variability exists. Correlation analysis revealed a strong, statistically significant negative relationship between January dry spells and maize yield (r = -0.703, p=0.0035), highlighting the vulnerability of crops to early-season water stress. Predictive models using logistic and linear regression suggested that temperature and rainfall patterns moderately influence the likelihood and duration of dry spells, although their predictive strength was limited. The findings underscore the importance of targeted drought monitoring and the integration of dry spell forecasting in agricultural planning. This research provides valuable insights for enhancing climate resilience, informing policy, and supporting adaptive strategies in maize-dependent farming systems in Southern Malawi.

Specifically, the study examines the trends in consecutive dry days (CDD) during January and February when the maize development is critical, alongside the temperature and rainfall data for planting and growth season (November to February). A dry day was defined as a day with less than 1mm of rainfall while for investigating dry spells we used the threshold of at least 7 consecutive dry days. Quality control and cleaning was done on the data set using Jupyterlab and Microsoft excel to determine the frequency of dry spell occurrence, assessment of its impact on maize production and the development of statistical predictive models. Mann-Kendall trend analysis showed no statistically significant trends in consecutive dry days (CDD) during January and February over the study period (2009–2023) as well as in rainfall and temperature, though notable inter-annual variability exists.

Zomba district was our area of focus in this study of investigating the occurrence of dry spells for agricultural application. It is located in the Southern Region of Malawi, bordered by Chiradzulu, Blantyre, Mulanje, Phalombe, Machinga, Balaka, and the Republic of Mozambique to the east. As shown in. The overall land area is 2,363 square kilometers, with a total population of 746,724 (Torrance, 1972). The district's main agricultural operations are the production of tobacco and cotton cash crops, as well as maize, rice, beans, and other pulses. Zomba District in Malawi is located at about 15.3833° S latitude and 35.3333° E longitude. Being in the Southern Hemisphere, its located south of the equator adding to its subtropical climate (National Planing Commission, 2024). This latitudinal location affects the duration of daylight hours and the angle of the sun, which later affects temperature fluctuations throughout the year. The Inter Tropical Convergence Zone (ITCZ) also influences climate of Zomba District, as it does throughout Malawi (Samba, 2012). During the wet season, which runs from November to April, the ITCZ brings heavy rain and high humidity to this area, making this time to be distinguished by high temperatures and lush greenery (Mkandawire, 2014).

Traditional authority: TA Malemia

District: Zomba

Coordinates: -15.28605, 35.3424