A detailed study of climate change and some vulnerabilities in Indian Ocean: A case of Madagascar island

Climate change continues to remain the main concern of all nations, and the adverse effects of this problem are enormous. This research was aimed to study the variation of outdoor climate in some regions of Madagascar, and also the assessment of impacts and vulnerabilities related to global warming. Toward this end, the daily data relating to the last 44 years have been studied. A first analyse has been carried out with several GCMs models, and scenarios(A2, A1B and B1), then RCM models associated to Representative Concentration Pathway(RCP) scenarios(RCP2.6, RCP4.5, RCP 6.0 and RCP 8.5). Chi-square Pearson tests and probabilities have been assessed to compare observed values and generated values. A significant values showed(P < 0.05). Finally, INCM3 model and A2 scenario showing an important correlation coefficient Pearson was used to carried out the forecasting in many cities in Madagascar.The results that were obtained show that temperature evolves more rapidly in the dry season than in the rainy season in these regions. An increase of more than 2 °C will be observed over the next decade. From 1990–2015, the degree of heat enhancement and multiple flooding resulted in the fall in farm production of more than 50%. In 1971, only two of cholera were registered in all the country. This number has increased up to 29,305 in 2000. In some areas, rice production had dropped by 75% between 2012 and 2014. Moreover, 3000 people were affected by “storms” between 1981 and 1989. The dry season was prolonged in recent years in areas with humid climate, and the degree of humidity decreased to 10% in the hot tropical climate. The prevalence of malnutrition increased conditions of vulnerability on every front.