Abstract

The IPCC fifth assessment report indicates an increase in air temperature under future scenarios over Mozambique. It may affect the development cycle and length of phenological stages of maize, and compromise the agricultural activity in Mozambique. The goal is to quantify the response of maize phenology to referred projected changes in climate, especially highlighting changes in air temperature patterns over Mozambique. Air temperature was simulated by a regional model, RegCM4, nested by global model HadGEM2 under two IPCC representative scenarios, RCP4.5 and RCP8.5 for far future (2070-2099) relative to the baseline period (1971-2000). The Growing Degree-Days method (GDD) was used to calculate the thermal units accumulated throughout the growing season over the study domain, considering the development cycle of the main cultivars used in Mozambique. However, unlike the widespread increase in accumulated thermal units, there is a reduction in accumulated GDD during the maize growing season over some regions of the country. Over some regions of the country, there is a reduction in accumulated GDD during the maize growing season, unlike the widespread increase in accumulated thermal units. In addition to the flattening of favorable areas for maize growing, another immediate consequence of this reduction is the lengthening of the maize development cycle and possible loss of productivity.

Key words: Climate change, growing degree-days, maize phenology.