The bulk surface properties, including canopy height (h), zero-plane displacement height (d), roughness length (z₀), and aerodynamic resistance (r_b and r_d), are crucial biophysical parameters that influence momentum, energy and mass exchanges at the land-atmosphere interface. The variabilities of these parameters are important for understanding possible impacts of the ecosystem on climate change, yet they have not been systematically evaluated due to the lack of large-scale, long-term observations. Here we provide global estimates of these bulk aerodynamic parameters, including d, z₀, r_b, and r_d, for the period 1982–2017 based on remote-sensed leaf area index (LAI), h, and plant functional type dependent canopy morphological characteristics. The global h estimate is acquired from LAI using a semi-empirical relation in which the coefficients have been optimized based on the canopy height product from the Geoscience Laser Altimeter System (GLAS) onboard the Ice, Cloud, and land Elevation Satellite (ICESat). Two LAI products, Global Land Surface Satellite (GLASS) and Global Inventory Modeling and Mapping Studies (GIMMS), are used to calculate canopy height and parameters separately. The products derived from the above two LAI datasets agree very well (spatial correlation coefficient, SCC = 0.99, relative root-mean-square-error, rRMSE = 8.28% for h, SCC = 0.99, rRMSE = 12.15% for d, and SCC = 0.98, rRMSE = 13.78% for z₀). Verification of the products against in-situ canopy height records from the FLUXNET and eddy-covariance (EC)-based d and z₀ estimates shows that the estimates can reproduce the annual means and seasonal variations of the bulk surface properties. We found significant positive trends in global h (0.04–0.05% year⁻¹), d (0.07% year⁻¹) and z₀ (0.07% year⁻¹) associated with the Earth greening, but they are different from the trend in LAI (0.14–0.25% year⁻¹). The differences between the trends in LAI and the trends in derived parameters are also found in different latitudes. For instance, in the Northern Hemisphere Polar region, the GLASS LAI increases by 0.48% year⁻¹, leading to positive trends of 0.03% year⁻¹ in h, 0.18% in d, and 0.20% year⁻¹ in z₀. The above results highlight the importance of comprehensively considering changes in LAI, canopy height, and aerodynamic parameters when evaluating the effects of ecosystem change on climate. This long-term dataset can be used in climate models to assess the response of bulk aerodynamic parameters to climate changes and the impact of vegetation dynamics on regional and global climate.

总体表面特性，包括冠层高度（h），零平面位移高度（d），粗糙度长度（z ₀）和空气动力学阻力（r _b和r _d），是影响动量，能量和质量的关键生物物理参数。在陆地-大气界面进行交换。这些参数的可变性对于理解生态系统对气候变化的可能影响很重要，但是由于缺乏大规模的长期观测，因此尚未对其进行系统的评估。在这里，我们提供了这些总体空气动力学参数的全局估计，包括d，z ₀，r _b和[R _d，基于远程感测的叶面积指数（LAI），周期1982至2017年ħ ，和植物功能类型依赖篷形态特征。全球h使用半经验关系从LAI获取估计值，其中基于冰，云和陆地高程卫星（ICESat）上的Geoscience激光测高仪系统（GLAS）的冠层高度积对系数进行了优化。两种LAI产品，即全球陆地卫星（GLASS）和全球清单建模与制图研究（GIMMS），分别用于计算冠层高度和参数。从以上两个LAI数据集得出的乘积非常吻合（空间相关系数，SCC = 0.99，相对均方根误差，h的rRMSE = 8.28％，s的SCC = 0.99，d的rRMSE = 12.15％，SCC = 0.98，z _0的rRMSE = 13.78％）。根据FLUXNET的原地冠层高度记录以及基于涡度协方差（EC）的d和z ₀估计值对产品进行验证，结果表明，这些估计值可以重现体表性的年度平均值和季节性变化。我们发现与地球绿化相关的全球h（0.04–0.05％年^-1），d（0.07％年^-1）和z ₀（0.07％年^-1）有显着的正趋势，但它们与LAI（0.14–0.25％年^-1）。LAI趋势与导出参数趋势之间的差异也出现在不同纬度上。例如，在北半球极地区域，玻璃LAI年增加了0.48％^-1，导致每年0.03％的积极趋势^-1的^ h，在0.18％d，和0.20％，比去年^-1在ž ₀。以上结果强调了在评估生态系统变化对气候的影响时，必须综合考虑LAI，冠层高度和空气动力学参数的变化的重要性。该长期数据集可用于气候模型，以评估整体空气动力学参数对气候变化的响应以及植被动态对区域和全球气候的影响。