Twenty-First Century Projected Changes in Extreme Temperature over Côte d’Ivoire (West Africa)

Abstract

The projection of the future climate changes is of paramount importance inasmuch as it contributes to provide useful information for adaptation planning worldwide to local scales. This study investigated the future changes using four temperature related indices based on an ensemble of 14 CORDEX-Africa simulations at 0.44° × 0.44° of resolution under the RCP4.5 and RCP8.5 scenarios. These indices indicate moderate extremes over Côte d’Ivoire. The results show an increase in the warm extreme indices such as the warm spell days index (HWFI), very warm days frequency index (TX90P), and the warm nights frequency index (TN90P) over the entire country under both emission scenarios. The increase in these indices was higher under RCP8.5 and reached 85, 72, and 90% for HWFI, TX90P, and TN90P respectively. In addition, the magnitude of the changes is relevant along the coastal areas in the 2031–2060 and 2071–2100 periods. Moreover, the intra period extreme temperature range (ETR) shows future decrease following a south-north gradient with values in the range [−0.5; 1.5°C] over the country during January–March (JFM) and October–December (OND) seasons whereas an increase (~0.5°C) is projected for April–June (AMJ) and July–September (JAS) seasons, particularly in the central and northern parts. The minimum temperature increases faster than the maximum, except in AMJ and JAS in the central and northern regions. On the other hand, the changes in the indices based on the mean values of the reference period (1976–2005) are in concordance to the expected warming at the end of the twenty-first century with important trends. The projected changes are, however, subject to uncertainties, which are higher under RCP8.5 than under RCP4.5 scenarios. Overall, these changes are meaningful as all the 14 CORDEX-Africa simulations agree to an increase of warm extreme temperature.

Potential changes in temperature extreme events under global warming at 1.5 °C and 2 °C over Côte d’Ivoire *

“…They further noticed that some models indicated that the temperature rise has already crossed the 2 • C GWL since the year 2012 and would continue to rise through 2066. Furthermore, the current results are in agreement with a similar analysis in temperature extreme over Côte d'Ivoire (Yapo et al 2019) that projected an increase, during the periods 2031-2060 and 2071-2100, in the frequency of warm spell days, very warm days, and the warm nights across the country, under both RCP4.5 and RCP8.5. Using the low-warming projections of NCAR-CESM to assess the differences in extreme temperature events under the GWLs at 1.5 • C and 2.0 • C, relative to the recent climate taken from 1976 to 2005 over Africa, Iyakaremye et al (2021) found that the frequency of occurrence of hot days (TX90P) is projected to increase with global warming across the African continent, while the frequency of cold day events (TN10P) is expected to decrease, especially across West Africa.…”

“…The current section focuses on the seasonal mean changes in TN10P, TN90P, TX10P, TX90P and HWDI under GWLs at 1.5 • C and 2 • C, across Côte d'Ivoire and for each of its climatic zones as defined in figure 1. Following Yapo et al (2019), four seasons, namely January-February-March (JFM), April-May-June (AMJ), July-August-September (JAS) and October-November-December (OND) have been used for each of the three climatic zones.…”

“…Over Côte d'Ivoire Yapo et al (2019Yapo et al ( , 2020 investigated future changes in temperature using the warm spell days index (HWFI), very warm days frequency index (TX90P), warm nights frequency index (TN90P), and intra-period extreme temperature range based on 14 of the Coordinated Regional Climate Downscaling Experiment (CORDEX)-Africa simulations ensemble under the RCP4.5 and RCP8.5 scenarios. They found moderate changes in extremes over Côte d'Ivoire and projected changes in the seasonal extreme precipitation intensity and dry spell length under RCP4.5 and RCP8.5 forcing scenarios, which suggested a robust increase in the cumulative intensity of precipitation associated with an amplification of extreme precipitation events during the West African Monsoon (WAM) period (Yapo et al 2020).…”

Contribution to the study of the seasonal dynamics of trace metals in the open waters at the water-sediment interface from a tropical lagoon estuary

“…In HS, the influence of the marine waters from Atlantic Ocean on this lagoon estuary is maximal, and the ambient temperature is maximal [46] . So, these marine inputs and ambient temperature would conduce to the slight basicity and the relative important temperature, salinity and, conductivity of these open waters.…”

Characterization of the variability in climate extremes in the Ferkessédougou sugar complexes (Northern Côte d'Ivoire)

“…The increase in temperature extremes can be attributed to heavy anthropisation and more particularly to the development of land use leading to the destruction of vegetation cover, which has increased over the last twenty years throughout the world (Abdalah, 2005). Thus, future projec-tions also predict an upward trend in these extreme temperature indices (Diedhiou et al, 2018;Yapo et al, 2019) namely heat wave episodes, heat waves, extremely hot and more frequent nights. These extreme events are thought to be related to wind anomalies opposing the mean circulation in the upper and lower troposphere of West Africa (Fontaine et al, 2013).…”