The climate of Nigeria is mostly tropical. Nigeria has three distinct climatic zones,[1][2] two seasons, and an average temperature ranging between 21 °C and 35 °C.[2] Two major elements determine the temperature in Nigeria: the altitude of the sun and the atmosphere's transparency (as determined by the dual interplay of rainfall and humidity).[2] Its rainfall is mediated by three distinct conditions including convectional, frontal, and orographical determinants.[2] Statistics from the World Bank Group showed Nigeria's annual temperature and rainfall variations, the nation's highest average annual mean temperature was 28.1 °C in 1938,[1] while its wettest year was 1957 with an annual mean rainfall of 1,441.45mm.[1]
The climate has a significant impact on the country's agriculture, economy, and society. The rainy season is the most important time for agriculture, as it is the time when most crops are planted and harvested.[3][4] The dry season is a time of drought, which can lead to water shortages and crop failures.[5] The high temperatures and humidity can also be uncomfortable and can lead to health problems.[6] Nigeria's climate is influenced by its geographical location, topography, and the interactions of various air masses.[7] Nigeria is situated in West Africa, between latitudes 4°N and 14°N, and longitudes 2°E and 14°E.[8] It experiences a tropical climate characterized by distinct wet and dry seasons.[9]
Nigeria has three distinct climatic zones.[2] According to the Nigerian Meteorological Agency, it is mainly tropical. It can be categorized into three including the tropical monsoon climate in the southern part, the tropical savannah climate, and Sahelian hot and semi-arid climate in the northern parts of the country.[2] While temperature and rainfall plays key roles in the determination of the country's climate, rainfall has been opined to be the key element based on its relevance and implications for agriculture.[10]
Tropical monsoon climate (Am)
Tropical monsoon climate can be found in south southern part of the nation. This climate generally has an estimated average annual rainfall of 2000mm[2] which varies for both the coastal areas and the inland regions. During the dry season, regions with this climate have a monthly mean temperature ranging from 23 °C (73 °F) during nighttime to 31 °C (88 °F) at daytime.[2]Port Harcourt, Delta and Bayelsa are examples of regions experiencing Tropical monsoon. The Am climate is found in the northern regions of Nigeria.[11] It is characterized by a shorter wet season and a longer dry season compared to the Aw climate. The average annual rainfall ranges from 600 to 1,200 mm.[12] The wet season usually lasts from May to September, while the dry season extends from October to April.[13]
Tropical savannah climate (Aw)
The tropical savannah climate is also called tropical wet and dry climate, as they tend to have both wet and dry seasons.[14] It could be either a lengthy dry season and a relatively short wet season; or a lengthy wet season and a relatively short dry season. The tropical savannah climate has a mean annual rainfall of about 1200mm or below, while the monthly mean temperature ranges from 22 °C (72 °F) during nighttime to 33 °C (91 °F) at daytime.[2]Lagos State is an example of a state with this type of climate. However, most central and southern parts of the nation also have this climate.
Sahelian hot (BWh) and semiarid climates (BSh)
The Sahelian hot and semiarid climates have average daytime temperatures of 35 °C (95 °F) and 21 °C (70 °F) at nighttime.[2] Regions experiencing this climate are majorly part of the Northern part of Nigeria and they experience very low annual mean rainfall below 700mm. Northern states like Kaduna, Jigawa and Sokoto are examples.[15]
Seasons
Nigeria has two seasons in a year: dry and wet.
Dry season
The dry season is accompanied by the dusty northeast winds where midday temperatures that can sometimes reach 100F (38C). During the dry season, there are lesser rainfalls, more sun and lower humidity. This period falls between October and April every year. It is normal to experience harmattan and dry spells during this period. The harmattan usually appears from December to January.[16] 1983 holds the record as the driest year Nigeria has ever seen since 1981.[17]
Wet season
The wet season is also referred to as rainy season. It falls between April and September every year. The wet season is particularly noticeable on the southeastern coast, where annual rainfall reaches about 130 inches (330 cm), where temperatures rarely exceed 90F (32C). 2019 holds the record as the wettest year Nigeria has ever seen since 1981.[16][17]
Temperature
Nigeria experiences high temperatures throughout the year, influenced by its location near the equator. The average annual temperature ranges from 25 °C to 32 °C, with regional variations based on factors such as elevation and proximity to water bodies.[18]
The average monthly temperature in Nigeria is between 24°C and 30 °C.[19]
The highest temperatures are usually seen between February and April during the dry season and are called the hot season. It falls between February and March ranging from 39.5 to 39.9 °C (103.1 to 103.8 °F) in the south, and March to May ranging from 42.9 °C to 44.5 °C in the north. In 2021, this period lasted until May.
In 2020, Nigeria saw a slight increase with southern states recording a mean average temperature of 30 °C - 32 °C while northern states had a record of 34 °C to 37 °C. Nigeria recorded 2021 as the year with the highest temperature in 40 years.[16]
Over the years, Nigeria has slowly become prone to various hazards due to change in climate. With the southern and coastal places at a risk of flooding due to rising sea levels. Further, they are also threatened with waterborne disease and vulnerable to more. States in the northern part of the country are experiencing higher temperatures, lesser rainfalls and are threatened by drought, famine, and food scarcity.[20]
Climate action
Nigeria joined the UN Environment's Climate and Clean Air Coalition in 2012 with the vision of reducing short-lived climate pollutants across ten high-impact sectors.
According to Nigerian Meteorological Agency (NIMET), Nigeria, with an annual mean temperature of 26.9 °C[22] has experienced heatwave with temperatures above 35 °C and with high occurrence rates in the northern part of the country.[23] The northern part is more vulnerable to heat waves due to the hot semi-arid climate. In 2019, Nigeria experienced a heatwave with northern states experiencing high occurrences as Minna had a temperature of 42.2 °C.[19] With 46.4 °C in 2010, the Nigerian city Yola had the highest recorded temperature in the list of countries and territories affected by extreme temperatures.
During the wet season, it is not unusual to experience rainfalls that can cause flooding in some parts of the nation. In 2012, the country experienced its worst in 40 years with an estimated loss of N2.6 trillion. A total of 363 people were killed and over 2,100,000 displaced.[24][25]
Houses submerged in Makurdi, Nigeria due to the flooding
The 2017 flooding that occurred during the rainy season in Benue state was another disaster that displaced a thousand people.[26] In 2021, 32 out of Nigeria's 36 states had cases of flooding according to the National Emergency Management Agency, reporting 155 lives lost between August and October.[16]
Nigeria was also among the affected countries that suffered severe famine in the 2012 Sahel drought.[28]
Prolonged drought in Nigeria has led to desertification and land scarcity for farming and livestock. This forces farmers and herders to migrate to new areas, often resulting in violent conflicts, with over 2,000 casualties in 2018. Despite these challenges, some Plateau State residents are reluctant to leave, rebuilding their communities after destruction. Satellite images from NASA reveal severe desertification, affecting about 900,000 km2 of savanna grassland between the 1960s and 1986.
Drought is a recurring issue in Nigeria, particularly in the arid north, with historical famines documented in various years. A recent survey by SBMIntel found that 79% of Nigerian farmers were impacted by drought and flooding in 2020, with 26.3% experiencing significant harvest disruptions. This poses a threat to national food security.
