Nigeria vegetation trend during recent West African monsoon season and the near future implications in CORDEX-Africa

IF 5.6 1区农林科学 Q1 AGRONOMY Agricultural and Forest Meteorology Pub Date : 2025-03-18 DOI:10.1016/j.agrformet.2025.110499

Ugochukwu K. Okoro, Chijioke U. Opara, Hyacinth C. Nnamchi, Wen Chen

{"title":"Nigeria vegetation trend during recent West African monsoon season and the near future implications in CORDEX-Africa","authors":"Ugochukwu K. Okoro, Chijioke U. Opara, Hyacinth C. Nnamchi, Wen Chen","doi":"10.1016/j.agrformet.2025.110499","DOIUrl":null,"url":null,"abstract":"This study investigated the impact of recent West African monsoon seasonal rainfall on the vegetation trend in Nigeria. Using Mann-Kendall test, the satellite estimates revealed increasing trends in the mean Normalized Difference Vegetation Index (NDVI) at 95 % in area of the location between 1981 and 2020 with statistical significance (at<span><span><math><mrow is=\"true\"><mspace is=\"true\" width=\"0.33em\"></mspace><mi is=\"true\">α</mi><mo is=\"true\">≤</mo><mn is=\"true\">0.5</mn></mrow></math></span><script type=\"math/mml\"><math><mrow is=\"true\"><mspace width=\"0.33em\" is=\"true\"></mspace><mi is=\"true\">α</mi><mo is=\"true\">≤</mo><mn is=\"true\">0.5</mn></mrow></math></script></span> levels of significance) in the south-western States. The 6-month Standardized Precipitation Index (SPI) from the Climate Research Unit (CRU) observational rainfall within the same period indicated increasing trends at 73 % of the area with statistical significance (at <span><span><math><mrow is=\"true\"><mi is=\"true\">α</mi><mo is=\"true\">≤</mo><mn is=\"true\">0.5</mn></mrow></math></span><script type=\"math/mml\"><math><mrow is=\"true\"><mi is=\"true\">α</mi><mo is=\"true\">≤</mo><mn is=\"true\">0.5</mn></mrow></math></script></span> levels of significance) in the northern States above the 9° N latitude. From the temporal correlations between the seasonal rainfall and vegetation trends, there was significant (at 95 % confidence level from the <em>t</em>-test) positive characteristic impact on 89 % of the area. The CORDEX-Africa historical experiment outputs (1981–2005) of the selected models and the ensemble mean revealed strong correlation values with high normalized RMSE when representing the seasonal rainfall simulation. The bias-corrected output (2006–2020) in the RCP 8.5 experiment showed notably enhanced representation quality of the models and the ensemble mean, with 87 % of the area demonstrating “reasonable performance” efficiency. The 6-month SPI projection from 2021 to 2050 indicated positive trends in 84 % of the area. Indeed, the relative percentage difference between projected and baseline trends compellingly suggests a decrease in seasonal rains by 2050, intensifying the demand on vegetation and introducing additional climate challenges.","PeriodicalId":50839,"journal":{"name":"Agricultural and Forest Meteorology","volume":"19 1","pages":""},"PeriodicalIF":5.6000,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Agricultural and Forest Meteorology","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1016/j.agrformet.2025.110499","RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"AGRONOMY","Score":null,"Total":0}

引用次数: 0

Abstract

This study investigated the impact of recent West African monsoon seasonal rainfall on the vegetation trend in Nigeria. Using Mann-Kendall test, the satellite estimates revealed increasing trends in the mean Normalized Difference Vegetation Index (NDVI) at 95 % in area of the location between 1981 and 2020 with statistical significance (at

α \leq 0.5

$α \leq 0.5$ levels of significance) in the south-western States. The 6-month Standardized Precipitation Index (SPI) from the Climate Research Unit (CRU) observational rainfall within the same period indicated increasing trends at 73 % of the area with statistical significance (at

α \leq 0.5

$α \leq 0.5$ levels of significance) in the northern States above the 9° N latitude. From the temporal correlations between the seasonal rainfall and vegetation trends, there was significant (at 95 % confidence level from the t-test) positive characteristic impact on 89 % of the area. The CORDEX-Africa historical experiment outputs (1981–2005) of the selected models and the ensemble mean revealed strong correlation values with high normalized RMSE when representing the seasonal rainfall simulation. The bias-corrected output (2006–2020) in the RCP 8.5 experiment showed notably enhanced representation quality of the models and the ensemble mean, with 87 % of the area demonstrating “reasonable performance” efficiency. The 6-month SPI projection from 2021 to 2050 indicated positive trends in 84 % of the area. Indeed, the relative percentage difference between projected and baseline trends compellingly suggests a decrease in seasonal rains by 2050, intensifying the demand on vegetation and introducing additional climate challenges.

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

求助全文

约1分钟内获得全文去求助

来源期刊

Agricultural and Forest Meteorology 农林科学-林学

CiteScore

10.30

自引率

9.70%

发文量

415

审稿时长

69 days

期刊介绍： Agricultural and Forest Meteorology is an international journal for the publication of original articles and reviews on the inter-relationship between meteorology, agriculture, forestry, and natural ecosystems. Emphasis is on basic and applied scientific research relevant to practical problems in the field of plant and soil sciences, ecology and biogeochemistry as affected by weather as well as climate variability and change. Theoretical models should be tested against experimental data. Articles must appeal to an international audience. Special issues devoted to single topics are also published. Typical topics include canopy micrometeorology (e.g. canopy radiation transfer, turbulence near the ground, evapotranspiration, energy balance, fluxes of trace gases), micrometeorological instrumentation (e.g., sensors for trace gases, flux measurement instruments, radiation measurement techniques), aerobiology (e.g. the dispersion of pollen, spores, insects and pesticides), biometeorology (e.g. the effect of weather and climate on plant distribution, crop yield, water-use efficiency, and plant phenology), forest-fire/weather interactions, and feedbacks from vegetation to weather and the climate system.