Inter-Annual Temperature Variability and Projections on its Irish Potatoes Production in Rwanda

Abstract

This study analyzed the inter-annual Temperature variability on potato production in Rwanda especially in Nyabihu and Musanze districts, the overall objective was to investigate the annual Temperature variability, projections and impacts on production volumes of Irish Potatoes to assess the information gaps that should otherwise be tailored for general famers. Specific objectives were to assess the annual Temperature variability and trends factors of temperature and Irish potato production volumes per district of the area of study, to identify the correlation of Irish potato production associated with temperature variability and to identify how the future will unfold based on the past behaviors Primary data on daily Tmax and Tmin from 2007 to 2017 was collected from Rwanda Meteorological Agency’ stations, where the respective stations which are Bigogwe, Jenda, Mukamira representative of Nyabihu district, Busogo, Musanze and Rwaza representative of Musanze District was sampled, Secondary data on annual potato production for both long and short rain season comprised between 2007 and 2017 were collected from RAB and NSRI. For the consistency of the good results the long rain season production was added to the short rain season production to get the annual yields in each year, again online Marksim simulated monthly present day climate data (Tertiary) were extracted and compared with the observed data to Assess the performance of Marksim model in simulating present day temperature, monthly projected data from 2010 to 2039 with the help of seventeen models were also extracted and projected with the help of RCPs to evaluate the future unfolding. The data collected were analyzed using Python, R, IBM SPSS statistics 23, CDT and Excel; the results were presented using trend lines and bar graphs, curves, radar with makers, tables and pie charts. The findings were that annual Tmax and Tmin shown an increasing trend between 2007 and 2017 and Annual potato production increase and decline in mid 2012 for both Districts, but to some extend the two variables exhibited weak negative correlation between them. Pearson’s r= -0.366 for Tmax and r= -0.369 for Tmin is close to 0 followed by the P value of 0.94 for TMax and 0.91 for Tmin which bigger than 0.05 (>5% significance interval), showing that there is a weak negative correlation between the two variables and that change in one variable are weak correlated with changes in the second variable, meanwhile there is weak statistical correlation between annual temperature and annual potato production. the projected annual maximum and minimum temperature from 2010 up 2039 with the help of RCP 2.6, RCP 4.5 and RCP 8.5 in the studied areas shows that an increase of Tmax and Tmin will be between 1-1.3oC and 0.2 -1.3 oC respectively within both Districts and this will lead to the decline of future potato production with no futher adaptation. The study recommends that Farmers should be encouraged to enhance crop diversification to caution them from temperature variability, to be focused of forecasting and to adopt cultivars that can be withstand ever to the increasing temperatures