World Bioclimates

Climate plays a major role in determining the distribution of plants and animals. Bioclimatology, the study of climate as it affects and is affected by living organisms, is key to understanding the patterns of forests and deserts on the landscape, where productive agricultural lands may be found, and how changes in the climate will affect rare species. This layer is part of the Ecophysiographic Project and is one of the four input layers used to create the World Ecological Land Units Map. This layer provides access to a 250m cell-sized raster with a bioclimatic stratification. The source dataset was a 30-arcsecond resolution raster (equivalent to 0.86 km2 at the equator or about a 920m pixel size). The layer has the following attributes: Temperature Description - Seven classes based on the number of growing degree days (the monthly mean temperature multiplied by number of days in the month summed for all months). The 1950 to 2000 monthly average temperature was used to calculate growing degree days. Values in this field and associated number of growing degree days are: Temperature Description Growing Degree Days Very Hot 9,000 – 13,500 Hot 7,000 – 9,000 Warm 4,500 – 7,000 Cool 2,500 – 4,500 Cold 1,000 – 2,500 Very Cold 300 – 1,000 Arctic 0 - 300 Aridity Description - Six classes based on an index of aridity calculated by dividing precipitation by evapotranspiration. Precipitation and evapotranspiration are average values from 1950 to 2000. Aridity Description Aridity Index Very Wet 1.5 – 70 Wet 1.0 – 1.5 Moist 0.6 – 1.0 Semi-dry 0.3 – 0.6 Dry 0.1 – 0.3 Very Dry 0.01 – 0.1 Bioclimate Class - a 2-part description that combines the value of the Temperature Description field and the Aridity Description field. The alias for this field is ELU Bioclimate Reclass. This layer was created by modifying the dataset documented in the publication: Metzger, M.J., Bunce, R.G.H., Jongman, R.H.G., Sayre, R., Trabucco, A. and Zomer, R. (2013), High-resolution bioclimate map of the world. Global Ecology and Biogeography, 22: 630-638. https://doi.org/10.1111/geb.12022 Dataset Summary Analysis: Optimized for analysis What can you do with this layer? This layer is suitable for both visualization and analysis. It can be used in ArcGIS Online in web maps and applications and can be used in ArcGIS Desktop. Restricted single source analysis means this layer has size constraints for analysis and it is not recommended for use with other layers in multisource analysis. This layer has query, identify, and export image services available. This layer is restricted to a maximum area of 16,000 x 16,000 pixels - an area 4,000 kilometers on a side or an area approximately the size of Europe. A service is available providing access to the data table associated with this layer. The data table services can be used by developers to quickly and efficiently query the data and to create custom applications. For more information see the World Ecophysiographic Tables. Optimized for analysis means this layer does not have size constraints for analysis and it is recommended for multisource analysis with other layers optimized for analysis. See the Living Atlas Imagery Layers Optimized for Analysis Group for a complete list of imagery layers optimized for analysis. This layer is part of a larger collection of landscape layers that you can use to perform a wide variety of mapping and analysis tasks. The Living Atlas of the World provides an easy way to explore the landscape layers and many other beautiful and authoritative maps on hundreds of topics. The Esri Community is a good resource for learning more about landscape layers and the Living Atlas of the World. To get started see the ArcGIS Living Atlas of the World online community. The Esri Insider article “The First Ecological Land Units Map of the World” provides an introduction to the Ecophysiographic Mapping project.气候在决定动植物分布格局中发挥着核心作用。生物气候学（Bioclimatology）作为研究气候与生命有机体相互影响关系的学科，是理解地表森林与荒漠分布、优质农用地区位，以及气候变化如何影响珍稀物种的关键所在。 本图层隶属于生态地貌制图项目（Ecophysiographic Project），是用于生成世界生态土地单元地图（World Ecological Land Units Map）的四类输入图层之一。该图层提供分辨率为250米像元的生物气候分层栅格（raster）数据集。其源数据集为30角秒（arcsecond）分辨率栅格，在赤道处等效面积约0.86平方千米，像元尺寸约920米。 本图层包含以下属性字段： 1. 温度描述（Temperature Description）：基于生长度日（Growing Degree Days，即各月平均气温乘以当月天数后全年累加）划分的7个等级。生长度日的计算采用1950年至2000年的月均气温数据。该字段及其对应生长度日区间如下： 极热（Very Hot）：9000–13500 炎热（Hot）：7000–9000 温暖（Warm）：4500–7000 凉爽（Cool）：2500–4500 寒冷（Cold）：1000–2500 极寒（Very Cold）：300–1000 极地（Arctic）：0–300 2. 干旱度描述（Aridity Description）：基于干旱指数划分的6个等级，干旱指数由降水量除以蒸散发（evapotranspiration）计算得到。降水量与蒸散发数据采用1950年至2000年的平均值。该字段及其对应干旱指数区间如下： 极湿（Very Wet）：1.5–70 湿润（Wet）：1.0–1.5 湿润适中（Moist）：0.6–1.0 半干旱（Semi-dry）：0.3–0.6 干旱（Dry）：0.1–0.3 极干旱（Very Dry）：0.01–0.1 3. 生物气候类别（Bioclimate Class）：结合温度描述字段与干旱度描述字段的双维度分类，其别名为ELU生物气候重分类（ELU Bioclimate Reclass）。 本图层基于以下文献中的数据集修改而成：Metzger, M.J., Bunce, R.G.H., Jongman, R.H.G., Sayre, R., Trabucco, A. 及 Zomer, R. (2013)，《全球高分辨率生物气候地图》，《全球生态学与生物地理学》，22卷：630-638。https://doi.org/10.1111/geb.12022 数据集摘要分析：针对分析优化 您可使用本图层完成以下操作： 本图层同时适配可视化与分析需求，可在ArcGIS Online（ArcGIS在线版）的网页地图与应用中使用，也可用于ArcGIS Desktop（ArcGIS桌面版）。 受限单源分析模式下，本图层存在分析尺寸限制，不建议与其他图层进行多源联合分析。本图层支持查询、识别与导出影像服务。本图层的最大分析面积限制为16000×16000像元——即边长约4000千米的区域，面积大致相当于欧洲全境。 此外，可通过配套服务访问本图层的数据表，开发者可利用该数据表服务快速高效地查询数据并定制开发应用程序。更多信息请参阅《世界生态地貌数据表》（World Ecophysiographic Tables）。 针对分析优化意味着本图层无分析尺寸限制，推荐与其他经分析优化的图层进行多源联合分析。如需完整的分析优化影像图层列表，请参阅《分析优化型活地图集影像图层》（Living Atlas Imagery Layers Optimized for Analysis）群组。 本图层隶属于更广泛的景观图层集合，可用于开展各类制图与分析任务。ArcGIS世界活地图集（Living Atlas of the World）提供了便捷的探索方式，可浏览各类景观图层及数百个主题下的优质权威地图。Esri社区（Esri Community）是了解景观图层与世界活地图集的优质资源，入门指引可参阅ArcGIS世界活地图集在线社区。Esri Insider专栏文章《全球首份世界生态土地单元地图》详细介绍了生态地貌制图项目。