9-second gridded continental Australia novel ecological environments for Reptiles 1990:2050 CanESM2 RCP 8.5 (CMIP5) (GDM: REP_r3_v2)

Novel ecological environments for Reptiles as a function of change in long term (30 year average) climates between the present (1990 centred) and projected future (2050 centred) under the CanESM2 model (RCP 8.5) based on Generalised Dissimilarity Modelling (GDM) of compositional turnover. This metric describes the nature of the projected 2050 centred future environmental conditions for each 9s grid square. Using a Generalised Dissimilarity Model of compositional turnover (the effects of changing environment on changing species), each future location is compared with the continent in the present. For each cell, the metric looks out to all other cells in the continent, and records the ecological similarity of the future state of the cell to the most similar cell in the present. A value of 1 indicates that the future environment is similar to a current location in the present, and perfect analogue can found somewhere in Australia. A value of 0 indicates that the most similar environment to be found in the present is ecologically so different that we would expect no species in common, i.e. there are no current analogues for this environment; it is novel. Intermediate values show how ecologically similar the most similar cell is. However, no weight is given to the proximity of the most similar cell. The environment may be similar, but the cells thousands of kilometres apart.This metric was developed along with others for use in an assessment of the efficacy of the protected area system for biodiversity under climate change at continental and global scales, presented at the IUCN World Parks Congress 2014. It is described in the AdaptNRM Guide “Implications of Climate Change for Biodiversity: a community-level modelling approach”, available online at: www.adaptnrm.org. Data are provided in two forms:1. Zipped ESRI float grids: Binary float grids (*.flt) with associated ESRI header files (*.hdr) and projection files (*.prj). After extracting from the zip archive, these files can be imported into most GIS software packages, and can be used as other binary file formats by substituting the appropriate header file.2. ArcGIS layer package (*.lpk): These packages contain can be unpacked by ArcGIS as a raster with associated legend.Additionally a short methods summary is provided in the file 9sMethodsSummary.pdf for further information.Layers in this 9s series use a consistent naming convention:BIOLOGICAL GROUP _ FROM BASE_ TO SCENARIO_ ANALYSISe.g. A_90_CAN85_S or R_90_MIR85_Lwhere BIOLOGICAL GROUP is A: Reptiles, M: Reptiles, R: reptiles and V: vascular plants\tLineage: Novel ecological environments were calculated using the highly parallel bespoke CSIRO Muru software running on a LINUX high-performance-computing cluster, taking GDM model transformed environmental grids as inputs. The similarity of the most similar present cell to the future environment of each cell was calculated.More detail of the calculations and methods are given in the document “9sMethodsSummary.pdf” provided with the data download. GDM Model: \tGeneralised dissimilarity model of compositional turnover in reptile species for continental Australia at 9 second resolution using ALA data extracted 28 February 2014 (GDM: REP_r3_v2)Climate data. Models were built and projected using:a) 9-second gridded climatology for continental Australia 1976-2005: Summary variables with elevation and radiative adjustmentb) 9-second gridded climatology for continental Australia 2036-2065 CanESM2 RCP 8.5 (CMIP5): Summary variables with elevation and radiative adjustment本数据集基于物种组成更替的广义相异性建模（Generalised Dissimilarity Modelling, GDM），依托CanESM2模式（RCP 8.5），以当前（以1990年为中心）与预测未来（以2050年为中心）时段的长期（30年平均）气候变化为变量，生成爬行动物的全新生态环境数据。 该指标用于描述每个9秒网格单元以2050年为基准的预测未来环境特征。借助物种组成更替的广义相异性模型（即环境变化对物种变化的影响机制），将每个未来区位与当前时段的澳洲大陆进行比对。针对每个网格单元，该指标会遍历大陆内所有其他网格单元，记录该单元未来环境状态与当前最相似网格单元的生态相似程度。当指标值为1时，表明该未来环境与当前某一区位的环境高度相似，澳大利亚境内可找到完全匹配的类似环境；当指标值为0时，表明当前可找到的最相似环境在生态层面差异极大，二者几乎无共有物种，即该环境无当前类似环境，属于全新生态环境。中间值则体现了最相似网格单元的生态相似程度。但该指标未考虑最相似网格单元的空间邻近性，即便环境相似，两个网格单元可能相距数千公里。 该指标与其他同类指标一同开发，用于大陆及全球尺度下气候变化背景下生物多样性保护区系统的效能评估，相关成果发表于2014年世界自然保护联盟（IUCN）世界公园大会。其详细说明见于AdaptNRM指南《气候变化对生物多样性的影响：群落级建模方法》，可通过网址www.adaptnrm.org在线获取。 本数据集提供两种格式： 1. 压缩版ESRI浮点栅格：包含二进制浮点栅格文件（*.flt）、配套的ESRI头文件（*.hdr）与投影文件（*.prj）。从压缩包解压后，这些文件可导入绝大多数地理信息系统（Geographic Information System, GIS）软件；通过替换对应头文件，也可作为其他二进制格式文件使用。 2. ArcGIS图层包（*.lpk）：此类文件可通过ArcGIS解压为带配套图例的栅格数据。 此外，数据附带的9sMethodsSummary.pdf文件提供了简要的方法概述，可供用户查阅更多细节。 本9秒系列栅格图层采用统一命名规则： 生物类群_基准时段_情景_分析类型 示例：A_90_CAN85_S 或 R_90_MIR85_L 其中生物类群对应如下：A为爬行动物、M为爬行动物、R为爬行动物、V为维管植物。 数据溯源：全新生态环境通过运行于Linux高性能计算集群的高度并行化定制化CSIRO Muru软件计算得到，输入数据为经广义相异性模型转换的环境栅格。本研究计算了每个网格单元的未来环境与当前最相似网格单元的生态相似程度。更多计算细节与方法说明可参阅数据附带的9sMethodsSummary.pdf文件。 广义相异性模型： 本模型基于2014年2月28日提取的ALA数据，以9秒分辨率构建澳大利亚大陆爬行动物物种组成更替的广义相异性模型（模型标识：REP_r3_v2）。 气候数据： 模型构建与预测所用气候数据如下： a) 1976-2005年澳大利亚大陆9秒分辨率栅格气候数据集：包含经高程与辐射校正的汇总变量 b) 2036-2065年澳大利亚大陆9秒分辨率栅格气候数据集（CanESM2模式RCP 8.5情景，CMIP5计划）：包含经高程与辐射校正的汇总变量