An Estimation of Regional Climate Sensitivity Using Annual Atmospheric Carbon Dioxide and Land Use Changes over Iraq

Abstract

Abstract Climate sensitivity is the measurement of rising average surface air temperature resulting from doubling the atmospheric carbon dioxide (CO2) concentrations and changes in land cover caused by human activities. Based on annual CO2 concentrations (2003–2016), built-up areas, and average surface air temperature, (1971–2022), this sensitivity is estimated in terms of transient climate response (TCR) and equilibrium climate sensitivity (ECS) and changes in built-up areas for three cities of Iraq: Basra, Baghdad, and Mosul as well as in the whole Iraq. The results show that the values of TCR and ECS in Baghdad are 6.2 and 9.2°C respectively, which are higher than the recommended range by IPCC 5th assessment report, thus the increase in CO2 concentrations will exacerbate regional warming effect, while their values (2.8 and 4.2°C) were found to be within this range for overall Iraq. Also, the results show that built-up area changes have been contributed to increase average air temperature in Basra and Baghdad, while they are not in Mosul, which seems to be affected more by global warming.