Surface Albedo Dominates Radiation Efficiency of Alpine Grasslands Along an Elevation Profile of Qilian Mountains

NWIPB OpenIR

	Surface Albedo Dominates Radiation Efficiency of Alpine Grasslands Along an Elevation Profile of Qilian Mountains
	Li, Hongqin; Zhang, Fawei; Zhu, Jingbin; Li, Jiexia; Guo, Xiaowei; Zhou, Huakun; Li, Yingnian
	2024
发表期刊	JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
卷号	129 期号:8
摘要	Quantifying the elevation dependency of radiation partitioning in high-altitude mountains is crucial for projecting regional energy balance while remains highly uncertain. We compared the surface radiation partitioning parameters across a meadow (3,200 m), shrub (3,400 m), and forb (3,600 m) along a southern slope of the Qilian Mountains. At a daily scale, the downward shortwave radiation (Rs) fluctuated minimally among the grassland types probably induced by similar site orientations. The greatest downward and upward longwave radiation (Ld and Lu) happened at the lowest meadow while the largest net shortwave (Sn) and longwave (Ln) radiation occurred at the deciduous shrub. The net all-wave radiation (Rn) of the meadow and shrub was similar and exceeded that of the forb by similar to 20%. The differences in Rn between the sites were jointly explained by those of upward shortwave radiation (Ru) and Lu, more than by Rs and Ld, suggesting the importance of surface attributes. The monthly normalized effective terrestrial radiation (lambda, the ratio of Ln to Rs) varied insignificantly among the sites and averaged 0.25 +/- 0.05, which was comparable to the global mean value (0.26). The smallest surface albedo (alpha, the ratio of Ru to Rs) and largest radiation efficiency (eta, the ratio of Rn to Rs) were 0.13 +/- 0.02 and 0.64 +/- 0.09, respectively, both at the shrub. Grassland type dominated the spatial variations of monthly alpha and eta. These findings highlighted the importance of grassland types to explain the spatiotemporal variations of radiation partitioning parameters in high-altitude alpine grasslands.An accurate understanding of the radiation budget and partitioning of high-altitude mountainous regions played a pivotal role in projecting the global climate system. This is especially true in the Qinghai-Tibetan Plateau, the so-called roof of the world, where there is a large scarcity of high-quality field observations from different vegetation types. We compared the four-component radiation measurements of alpine grasslands along an altitudinal gradient (a meadow at 3,200 m, a shrub at 3,400 m, and a forb at 3,600 m) of a southern slope of the Qilian Mountains. We found that the incoming shortwave radiation changed little across the three sites. However, the lowest meadow had the largest incoming and outgoing longwave radiation. The net all-wave radiation of the meadow and shrub exceeded that of the highest forb. The shrub had the lowest annual surface albedo and the biggest annual radiation efficiency. The annual normalized effective terrestrial radiation fluctuated minimally across the three sites and was comparable to the global mean value. Grassland type was the most important variable responsible for the variations of surface albedo and radiation efficiency. Our findings underscored the importance of taking surface attributes into account when projecting radiation budget and partitioning in high-altitude alpine grasslands.The differences in net all-wave radiation were jointly explained by the differences in upward shortwave and longwave radiation The normalized effective terrestrial radiation was conservative among these grasslands and comparable to the global mean value Grassland type, more than environmental variables explained the spatiotemporal variations of surface albedo and radiation efficiency
收录类别	SCIE
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/62045
专题	中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Li, Hongqin,Zhang, Fawei,Zhu, Jingbin,et al. Surface Albedo Dominates Radiation Efficiency of Alpine Grasslands Along an Elevation Profile of Qilian Mountains[J]. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES,2024,129(8).
APA	Li, Hongqin.,Zhang, Fawei.,Zhu, Jingbin.,Li, Jiexia.,Guo, Xiaowei.,...&Li, Yingnian.(2024).Surface Albedo Dominates Radiation Efficiency of Alpine Grasslands Along an Elevation Profile of Qilian Mountains.JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES,129(8).
MLA	Li, Hongqin,et al."Surface Albedo Dominates Radiation Efficiency of Alpine Grasslands Along an Elevation Profile of Qilian Mountains".JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES 129.8(2024).