Report: Three characteristics are classically required to guarantee the democratic legitimacy of political participation processes: the descriptive or demographic representativeness of the assembled publics (input legitimacy), their inclusive character and the quality of their deliberation (throughput legitimacy) and the scope of the results (output legitimacy). For the French Citizens' Convention for Climate (CCC), "150" citizens were drawn at random to constitute a "France in miniature ", as representative as possible of the diversity of the population aged 16 and over residing on national soil. This volume A of the Raw Data from the Observation of the French Citizens' Convention for Climate examines the descriptive representativeness of the CCC by presenting tables summarizing the distribution of the citizens drawn and then present during the sessions according to the different sociodemographic characteristics retained for their selection.