ISIMIP3a population input data

The Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) provides a framework for the collation of a consistent set of climate impact data across sectors and scales. It also provides a unique opportunity for considering interactions between climate change impacts across sectors through consistent scenarios.<br>The ISIMIP3a part of the third simulation round is dedicated to i) impact model evaluation and improvement and ii) detection and attribution of observed impacts according to the framework of IPCC AR5 Working Group II Chapter 18. To this end all simulations are driven by observed socio-economic information combined with either observed (factual) climate data or a detrended (counterfactual) version of the observed climate allowing for the generation of a “no climate change” baseline.<br>This dataset contains the national and gridded historical population data for ISIMIP3a. Estimates are available for total as well as urban and rural population counts.

部门间影响模型比对计划（Inter-Sectoral Impact Model Intercomparison Project，ISIMIP）提供了一套跨部门、跨尺度整合一致气候影响数据的研究框架，同时也为通过统一情景分析跨部门气候变化影响间的相互作用提供了独特契机。
第三轮模拟中的ISIMIP3a部分，旨在达成两大目标：一是开展影响模型的评估与优化；二是依据《政府间气候变化专门委员会（Intergovernmental Panel on Climate Change，IPCC）第五次评估报告（AR5）第二工作组第18章》的框架，对已观测到的气候影响进行检测与归因。为此，所有模拟均以观测得到的社会经济信息作为驱动因子，结合两类气候数据：一类为实际观测的（事实性）气候数据，另一类为经去趋势处理后的观测气候数据（反事实数据），以此可构建出"无气候变化"的基准情景。
本数据集包含ISIMIP3a所需的国家级与网格化历史人口数据，可提供总人口、城镇人口及乡村人口的统计估算值。