A climatologist, Prof. Ibidun Adelekan, has warned that unpredictable weather patterns caused by climate change pose serious risks to farmers in Nigeria.
Adelekan, of the Department of Geography, University of Ibadan, told reporters on Monday in Ibadan that climate change has resulted in erratic rainfall patterns and increased flooding across the country.
“When rainfall becomes unpredictable, farmers can no longer rely on traditional planting calendars. Flooding can destroy crops, damage farmland and threaten food security,” she said.
The expert called for improved urban planning, better drainage infrastructure, environmental protection and increased public awareness to mitigate the impacts of climate change in Nigeria.
Adelekan said climate change has significantly altered Nigeria’s weather patterns, leading to delayed harmattan seasons, heavier rainfall, rising temperatures and widespread flooding.
She noted that long-established seasonal patterns were no longer reliable, posing growing risks to farmers, urban residents and coastal communities.
According to her, the harmattan season, which used to begin as early as November in southern Nigeria, now sets in much later.
Adelekan recalled that in the early 1980s, harmattan conditions often began by mid-November, particularly during graduation periods at the University of Ibadan.
“We were almost at the end of January before the harmattan was felt in southern Nigeria. This late onset has been the experience over the last three years,” she said.
The don explained that Nigeria’s climate is largely influenced by the Inter-Tropical Discontinuity (ITD), the boundary between dry northeasterly winds from the Sahara and moisture-laden southwesterly winds from the Atlantic Ocean.
“The position and movement of the ITD determine whether an area experiences harmattan or rainfall. What we are seeing now is a delayed southward movement of the ITD, which explains why harmattan is coming later than it used to,” she said.
Adelekan also noted significant changes in rainfall patterns across the country, including southern Nigeria where rains traditionally begin early.
“Rainfall is now starting later, but when it comes, it is more intense. We now experience fewer rainy days but heavier rainfall,” she said.
She added that the combination of intense rainfall and rapid urban development has worsened flooding in many Nigerian cities.
“With more buildings, roads and concrete surfaces, rainwater can no longer infiltrate the soil as it used to. Instead, it flows rapidly as runoff, overwhelming drainage systems that were built decades ago when rainfall was less intense,” she explained.
The climatologist further identified blocked drainage systems, caused by indiscriminate waste disposal, as a major contributor to urban flooding.
“In the past, there was less plastic waste. Today, plastic bottles and other refuse clog drainage channels, reducing their capacity and causing flash floods even after moderate rainfall,” she said.
Adelekan also observed a shift in weather patterns in northern Nigeria, which was previously associated mainly with drought.
“Historically, northern Nigeria was known for dry conditions and drought. Today, we are witnessing more flooding incidents in areas that rarely experienced flooding in the past,” she said.
She explained that climate change and global warming have intensified the hydrological cycle, leading to increased evaporation, cloud formation and heavier rainfall.
Rising temperatures, she added, are also becoming more noticeable across the country.
“We are experiencing more extremely hot days than before, particularly during the dry season,” Adelekan said.
The expert attributed global warming to factors such as deforestation, rapid urbanization, increased use of generators, industrial activities and greenhouse gas emissions.
“When vegetation is removed, less carbon dioxide is absorbed from the atmosphere. At the same time, human activities release more greenhouse gases, trapping heat and warming the atmosphere,” she said.
