VICGlobal: soil and vegetation parameters for the Variable Infiltration Capacity hydrological model

## VICGlobal: soil, vegetation, and elevation band input files for the VIC hydrological model Date updated: June 28, 2021 Authors and affiliations: Jacob Schaperow (1), Dongyue Li (1,2) 1. Department of Civil and Environmental Engineering, UCLA 2. Department of Geography, UCLA Author contact info: [e-mail] The current version, v1.6d improves upon v1.6c by splitting the image parameters by continent, reducing file sizes. v1.6c is the same as v1.6, except that the image mode parameters have been updated to reflect the changes made to the classic mode parameters (e.g. r0 and rmin are different, and albedo, fcanopy, and LAI are calculated based on snow-free values). ## Overview VICGlobal is a dataset that can be used to run the Variable Infiltration Capacity (VIC) hydrological model over regional to continental scales. The dataset is at 1/16 degree resolution and has latitudinal coverage from -60 to 85 degrees. All files are referenced to the WGS84 ellipsoid and datum (EPSG code 4326). The vegetation parameter file uses the IGBP classification and use partial land use types. The vegetation parameter rooting depths and root fractions are based on the method of Zeng (2001). The vegetation library file is largely the same as that of Livneh et al. (2013; 2015); however, the monthly average LAI, canopy fraction, and albedo values for each land cover type are calculated based on MODIS observations from 2017, using the method of Bohn and Vivoni (2019). There are two vegetation libraries: one for the northern hemisphere, and one for the southern hemisphere, in order to account for the seasonality of LAI, canopy fraction, and albedo. WARNING: although it appears small in compressed form, the image driver parameter input file, VICGlobal_params.nc, is about 140 GB when unzipped. Users are encouraged to use the image mode parameters that are already split by continent. For example, the parameter file for Africa is about 19 GB. A data descriptor is in preparation for submission to Nature Scientific Data (https://www.nature.com/sdata/). Other VIC input datasets (coverage limited to North America): * Bohn and Vivoni MOD-LSP dataset: https://zenodo.org/record/2559631 ## List of contents Inputs for VIC-4 or the VIC-5 Classic Driver * Soil parameter file * Vegetation parameter file * Elevation band file * Vegetation library files (one each for the northern and southern hemispheres) Inputs for the VIC-5 Image Driver * Parameter file (global) * Domain file (global) * Parameter files for each continent * Africa * Australia * Eurasia (except Kamchatka) * Kamchatka * North America * Oceania (New Zealand and nearby islands) * South America * Domain files for each continent * GeoTiffs with continent masks Matlab codes for subsetting the VICGlobal parameters to a region of interest are also provided. ## References * Bohn and Vivoni (2019). MOD-LSP, MODIS-based parameters for hydrologic modeling of North American land cover change. https://www.nature.com/articles/s41597-019-0150-2 * Livneh et al. (2015). A spatially comprehensive, hydrometeorological data set for Mexico, the U.S., and Southern Canada 1950–2013. https://www.nature.com/articles/sdata201542 * Livneh, B., Rosenberg, E. A., Lin, C., Nijssen, B., Mishra, V., Andreadis, K. M., Maurer, E. P. and Lettenmaier, D. P.: A long-term hydrologically based dataset of land surface fluxes and states for the conterminous United States: Update and extensions, J. Clim., 26(23), 9384–9392, doi:10.1175/JCLI-D-12-00508.1, 2013. * Zeng (2001). Global Vegetation Root Distribution for Land Modeling. Journal of Hydrometeorology. https://doi.org/10.1175/1525-7541(2001)002<0525:GVRDFL>2.0.CO;2

VICGlobal：用于可变下渗容量（Variable Infiltration Capacity, VIC）水文模型的土壤、植被与高程波段输入文件
更新日期：2021年6月28日
作者及所属机构：Jacob Schaperow(1)、李东悦(1,2)
1. 加州大学洛杉矶分校（UCLA）土木与环境工程系
2. 加州大学洛杉矶分校（UCLA）地理系
作者联系方式：[e-mail]

当前版本v1.6d基于v1.6c优化而来，通过按大洲拆分图像参数以减小文件体积。v1.6c与v1.6基本一致，仅更新了图像模式参数以适配经典模式参数的变更（例如r0与rmin参数已调整，反照率、冠层占比fcanopy以及叶面积指数（Leaf Area Index, LAI）均基于无雪条件计算）。

## 概述
VICGlobal是一款可用于在区域至大洲尺度上运行可变下渗容量（VIC）水文模型的数据集。该数据集分辨率为1/16度，纬度覆盖范围为-60°至85°，所有文件均参考WGS84椭球体与基准面（EPSG代码4326）。植被参数文件采用IGBP（国际地圈生物圈计划，International Geosphere-Biosphere Programme）分类体系，并包含部分土地利用类型。植被参数的根系深度与根系占比基于Zeng（2001）提出的方法确定。植被库文件整体与Livneh等人（2013；2015）的成果基本一致，但各土地覆盖类型的月均叶面积指数、冠层占比与反照率数值基于2017年的MODIS观测数据，采用Bohn与Vivoni（2019）的方法计算得到。为适配叶面积指数、冠层占比与反照率的季节变化特征，数据集包含两套植被库：分别对应北半球与南半球。

## 警告
尽管压缩后体积较小，但图像驱动模式参数输入文件VICGlobal_params.nc解压后体积约为140 GB。建议用户使用已按大洲拆分的图像模式参数文件，例如非洲地区的参数文件体积约为19 GB。相关数据描述文稿已提交至《Nature Scientific Data》（https://www.nature.com/sdata/）待刊。

其他仅限北美地区的VIC输入数据集：
* Bohn与Vivoni MOD-LSP数据集：https://zenodo.org/record/2559631

## 数据集内容
### 适用于VIC-4或VIC-5经典驱动模式的输入文件
* 土壤参数文件
* 植被参数文件
* 高程波段文件
* 植被库文件（北半球与南半球各一套）

### 适用于VIC-5图像驱动模式的输入文件
* 全局参数文件
* 全局域文件
* 各大洲参数文件：
- 非洲
- 澳大利亚
- 欧亚大陆（不含堪察加半岛）
- 堪察加半岛
- 北美洲
- 大洋洲（新西兰及邻近岛屿）
- 南美洲
* 各大洲域文件
* 带大洲掩膜的GeoTIFF文件

此外，还提供了用于将VICGlobal参数裁剪至指定研究区域的Matlab代码。

## 参考文献
1. Bohn, T. J. & Vivoni, E. R. MOD-LSP：基于MODIS的北美土地覆盖变化水文模拟参数集。《科学数据》6, 120 (2019). https://www.nature.com/articles/s41597-019-0150-2
2. Livneh等。1950–2013年墨西哥、美国与加拿大南部的全域综合水文气象数据集。《科学数据》2, 150042 (2015). https://www.nature.com/articles/sdata201542
3. Livneh, B. et al. 美国本土陆面通量与状态的长期水文数据集：更新与扩展。《气候杂志》26, 9384–9392 (2013). https://doi.org/10.1175/JCLI-D-12-00508.1
4. Zeng, X. 陆面模型中的全球植被根系分布。《水文气象学杂志》2, 525–537 (2001). https://doi.org/10.1175/1525-7541(2001)002<0525:GVRDFL>2.0.CO;2

搜集汇总

背景与挑战

背景概述

VICGlobal是一个为Variable Infiltration Capacity（VIC）水文模型设计的全球数据集，提供土壤、植被和高程带参数，覆盖-60至85度纬度范围，分辨率为1/16度。该数据集基于IGBP分类和MODIS观测数据，植被参数考虑季节性并分为南北半球，同时提供按大陆分割的参数文件以优化存储和使用。