CCCma_SRES_B2_PREC

Project: IPCC Data Distribution Centre : Third Assessment Report data sets
The Intergovernmental Panel on Climate Change (IPCC) has been established by WMO und UNEP to assess scientific, technical and socio-economic information, relevant for the understanding of climate change, its potential impacts and option for adaption and migration. Projection of future trends for a number of key variables are provided through this section of the DDC (http://www.mad.zmaw.de/IPCC_DDC/html/ddc_gcmdata.html). This information contained in either IS92 emission scenarios (IPCC 1992), the Special Report on Emission Scenarios (IPCC 2000, SRES) or published model studies using data from these scenarios. Six alternative IPCC scenarios (IS92a to f) were published in the 1992 Supplementary Report to the IPCC Assessment. These scenarios embodied a wide array of assumption affecting how future greenhouse gas emissions might evolve in the absence of climate policies beyond those already adoped. The SRES scenarios have been constructed to explore future developments in the global enviromental with special reference to the production of greenhouse gases and aerosol precursor emission.
A set of four scenario families (A1, A2, B1, B2) have been developed that each of this storylines describes one possible demographic, polito-economic, societal and technological future. Model experiments, also using different forcing scenarios, were calculated at other modeling centres. Emissions Scenarios. 2000 ,Special Report of the Intergovernmental Panel on Climate Change Nebojsa Nakicenovic and Rob Swart (Eds.) Cambridge University Press, UK. pp 570
Summary: The SRES data sets were published by the IPCC in 2000 and classified into four different scenario families (A1, A2, B1, B2). SRES_B2 storyline describes a world in which the emphasis is on local solutions to economic, social and enviromental sustainability. The global population is increasing at a lower rate than A2. It has an intermediate level of economic development and a less rapid and more diverse technological change than in A1 and B1. The atmospheric component AGCM2 is a spectral model with triangular truncation at wave no. 32 and 10 vertical levels. The ocean model component based on the GFDL MOM 1.1 code with 29 vertical levels and has a iospycnal / eddy stirring parameterization (Gent and McWilliams,1990). CGCM2 (http://www.cccma.bc.ec.gc.ca/models/cgcm2.shtml ). The changes of anthropogenic emissions of CO2, CH4, N2O and sulphur dioxide are prescribed according to the above mentioned scenario. These data belongs to a set of three ensemble runs, with the CCCma-model, using the SRES_B2 scenario. They provide monthly averaged values of selected variables for the IPCC-DDC.

项目：政府间气候变化专门委员会（Intergovernmental Panel on Climate Change, IPCC）数据分发中心（Data Distribution Centre, DDC）：第三次评估报告数据集
世界气象组织（World Meteorological Organization, WMO）与联合国环境规划署（United Nations Environment Programme, UNEP）联合设立政府间气候变化专门委员会，旨在评估与理解气候变化、其潜在影响以及适应与迁移方案相关的科学、技术与社会经济信息。本数据分发中心的该板块（http://www.mad.zmaw.de/IPCC_DDC/html/ddc_gcmdata.html）提供了若干关键变量的未来趋势预测结果。
此类信息要么源自IS92排放情景（IPCC，1992年）、排放情景特别报告（IPCC，2000年，简称SRES），要么源自基于上述情景数据开展的已发表模型研究。IPCC在1992年《IPCC评估报告补充报告》中发布了6种备选情景（IS92a至IS92f）。这些情景涵盖了一系列假设，用于模拟在未实施额外气候政策的前提下，未来温室气体排放的演变路径。
SRES情景的构建旨在探究全球环境的未来发展态势，尤其聚焦于温室气体和气溶胶前体物的排放情况。研究人员构建了4类情景族（A1、A2、B1、B2），每类情景均对应一种可能的人口、政治经济、社会与技术发展前景。其他建模中心也基于不同的强迫情景开展了模型试验。
*排放情景*（2000年）：政府间气候变化专门委员会特别报告，Nebojsa Nakicenovic与Rob Swart主编，英国剑桥大学出版社，共570页。
## 概述
SRES数据集由IPCC于2000年发布，分为4类情景族（A1、A2、B1、B2）。SRES_B2情景对应一种以本地方案解决经济、社会与环境可持续发展问题的世界图景：全球人口增速低于A2情景；经济发展水平处于中等区间；技术变革速度慢于A1与B1情景，且技术路径更为多元。
大气分量模式AGCM2为谱模式，采用波数32的三角形截断，垂直分层共10层。海洋分量模式基于GFDL MOM 1.1代码开发，垂直分层共29层，并采用等密度面/涡旋扰动参数化方案（Gent与McWilliams，1990年）。CGCM2模式（http://www.cccma.bc.ec.gc.ca/models/cgcm2.shtml）的人为排放强迫基于上述情景设定，涉及二氧化碳（CO₂）、甲烷（CH₄）、一氧化二氮（N₂O）与二氧化硫的人为排放变化。本数据集为采用SRES_B2情景的CCCma模式的3个集合模拟试验结果，为IPCC数据分发中心提供了选定变量的月均数值。