1990 to 2045 Atmospheric SO2 Ancillary Files for HadCM3

SO2 emissions are a major source of uncertainty for climate model studies. From the Coupled Model Intercomparison Project Phase 5 (CMIP5) historical data and representative concentration pathway (RCP) data is readily available for use in climate models. However the contribution from observational data ceases after 2005 and therefore simulations of the recent past are dependent on up to 10 year old projection data. Here the authors have made use of more recent observations and projection scenarios from the ECLIPSE_v5a global emissions dataset. The 5 yearly SO2 land observations have been combined with shipping data, split into surface and high level emissions, interpolated in time to give monthly values and converted to N96 in the data format used by the MetOffice HadCM3 family of climate models. Data is available for the baseline current legislation (CLE), climate 2 degrees CLE and Maximally Technically Feasible reduction scenarios with data covering the period 1990 - 2045. To broaden the reuse of this data for other climate models both MetOffice ancillary files and NetCDF output files are included as well as two different methods by which the allocation of different emitters to the low and high level layers.<br>二氧化硫排放是气候模型研究中不确定性的主要来源。耦合模式比较计划第五阶段（Coupled Model Intercomparison Project Phase 5, CMIP5）的历史数据与典型浓度路径（Representative Concentration Pathway, RCP）数据可直接用于气候模型研究，但观测数据的贡献在2005年后中断，因此对近年气候的模拟依赖的是最长可达10年的滞后预测数据。本研究团队采用了ECLIPSE_v5a全球排放数据集的最新观测与预测情景数据：将每5年一次的陆地二氧化硫观测数据与航运排放数据整合，划分为地表与高空两类排放，通过时间插值生成月度数据，并转换为英国气象局（MetOffice）HadCM3系列气候模型所采用的N96数据格式。该数据集涵盖1990年至2045年的三类情景：现行立法基线情景（Current Legislation, CLE）、2℃气候目标CLE情景，以及最大技术可行减排情景。为推动该数据集在其他气候模型中的复用，本数据集附带英国气象局辅助文件与NetCDF格式输出文件，并提供两种将不同排放源分配至低层与高层排放层的方法。