By Watuwa Timbiti
Uganda will suffer severe effects of climate change especially between in 2070- 2100, according to a research published in the African Crop Science Journal.
Although 2070 may appear remote, the effects of climate change may be felt even earlier, the researchers warned.
With expected global temperature increases of 1.40C to 5.80C by the end of the 21st century, the research warns that sub-Saharan Africa, especially Uganda, are vulnerable to the adverse impacts of climate change since their economies are tightly bound to climate
The team of researchers from the College of the Agricultural and Environmental Sciences at Makerere University, in collaboration with bodies such as the water ministry, conducted the study.
They covered the whole of Uganda using observing stations countrywide. According to Prof. Majaliwa Mwanjalolo at the Department of Geography and Climate Sciences at Makerere, crops need certain temperatures and amounts of rainfall for proper growth.
“With an increase or decrease in temperature such crops may not yield highly,” he explains. He says this inhibits food production as well as food security.
With higher temperatures, Mwanjalolo adds, there is increased evaporation leading to plants receiving less water to produce biomass.
“High temperatures also favour the spread of some diseases and pests like grasshoppers. For humans, if the temperature changes from 300C to 320C, the way one’s body functions changes, which comes with costs,” he says.
He explains: “You may have to take more water to cool the body down.” In related research findings on the vegetation biomass in the cattle corridor of Uganda, it is noted that there is a correlation between rainfall and vegetation cover.
“The rainy seasons will have the highest vegetation and the dry ones will have the lowest vegetation, resulting in livestock mobility,” the research notes.
Mwanjalolo warns that although the increases in temperatures and decreases in rainfall are projected for 2070- 2100, such climate changes could happen before then.
Projected rainfall over Uganda (2070-2100)
During March to May (MAM) and September to October (SON), which are rainy seasons, the research projects several parts of the country will receive about 4-8mm of rainfall per day.
Areas like Lake Victoria and Rwenzori are likely to receive higher amounts of rainfall ranging from 10-16mm per day during those seasons.
During the June to August dry season (JJA), a large portion of the cattle corridor, the Lake Albert area and the south-western part of Lake Victoria are likely to receive 0-4mm of rainfall per day.
“North-western Uganda and other areas bordering Kenya and the Democratic Republic of Congo, are likely to receive 4-8mm of rainfall per day,” the research states.
Temperature to increase
The average surface temperature, according to the research, is likely to increase for all seasons. “The maximum for MAM is projected to increase by 10C and by 70C for SON, while the minimum for MAM is projected to increase by 1.60C and 1.40C for SON,” the research notes.
On the other hand, during the dry season, the temperature is projected to decrease slightly by 0.10C, while the minimum will increase by 0.60C.
“During rainy seasons, most of northern Uganda may remain hot; while the Mountain Elgon and southwestern regions are likely to be cool throughout the year,” the research adds.
In an interview in The East African, December 8-14, 2012, Ray Willson, a climate change expert, observes that to stem the effects of climate change on agriculture, scientists in East Africa should focus on finding new crops suitable for these changing times.
“Genetically modified crops and irrigation crops are some of the options available,” Willson advises. He notes reducing carbon emissions can also combat climate change.
He recommends a transition to low carbon emitting vehicles. “Governments should start investing in alternative energy sources like solar, wind and water. These are not only cheap, but are also good for increasing food security,” Willson notes.
Policies on combating climate change adaptation, he advises, should be drafted and adopted by both civil societies and nations.
In his book, Global Warming: Who is taking the heat?, a 1991 publication, Gerald Foley observes that making charcoal is particularly damaging because it produces a substantial amount of methane. “It is also destructive of forest resources, since charcoal-makers cut down trees,” he notes.
Improved cooking stove programmes, especially those focused on dissemination of improved charcoal stoves in urban areas, Foley advises, can help combat global warming. By reducing charcoal use, he argues, carbon dioxide and methane emissions are reduced.
On the other hand, Foley calls for reforestation, observing that the amount of carbon absorbed by a growing tree depends upon the species, the climate and the soil; it varies with the age of the tree.
“The rate of growth, and hence the amount of carbon fixed is greatest in the early years and tapers off as the tree matures,” he says.