玉龙雪山白水1号冰川冰川物质平衡数据（2008-2017）

1、 数据内容：玉龙雪山白水1号冰川2008年-2017年冰川物质平衡数据
2、数据来源及加工方法：在玉龙雪山白水1号冰川海拔高度为4600m至4800m之间海拔每隔100m布设花杆。每年5月消融期初和8月消融期末各观测一次；连续观测间隔时间为7天，如遇大雾，大雨，大雪等特殊情况下，无法观测，则会推迟观测时间。物质平衡是冰川表面积累量与消融量的代数和，反映了冰川表面单位面积上相对于上一个物质平衡年末，冰面的物质平衡平均升降变化状况。根据野外观测数据，花杆观测单点物质平衡为：bn=bs+bi+bsi, bn、bi、bs、bsi:分别代表单点物质平衡、冰川冰、积雪和附加冰平衡值，将计算结果标在大比例冰川图及地形图上，以50m为间距在等高线范围内画出消融、积累值。此外，计算了4700m观测点处，每月花杆及雪坑消融积累的水当量。分别量测出每相邻两等高线间的积累和消融面积，然后逐步计算出冰川消融区冰川的纯积累量C和纯消融量A以及物质平衡值B。通过Arcgis软件利用空间插值方法绘制积消等值线图，实现对整个冰川物质平衡的计算。整条冰川的年净物质平衡B为: 𝐵=Σ𝑏𝑖（𝑠𝑖/S𝑛i）,式中:si 为两相邻等值线的投影面积；bi 为si 的平均净平衡；n为si 总数；S为冰川总面积。
3、数据质量描述：用卷尺测量不同位置的花杆在观测时的出露高度值，以及测杆的高度、附加冰厚度、积雪剖面和污化层深度等，其单位为毫米水当量（mm w.e.）,观测主要在消融期进行。在观测期间，有部分花杆倾倒或被雪覆盖，无法获取有效数据.
4、数据应用成果及前景：数据可为冰川动力学模式和模拟研究提供参数率定及验证。。

1. Data Content: Glacier mass balance data of Baishui Glacier No.1, Yulong Snow Mountain, spanning from 2008 to 2017.

2. Data Source and Processing Methods: Glacier stakes were installed at 100-meter intervals between 4600 m and 4800 m above sea level (a.s.l.) on Baishui Glacier No.1, Yulong Snow Mountain. Two field surveys were conducted annually: one at the onset of the ablation season in May, and another at the end of the ablation season in August. Continuous observations were carried out at 7-day intervals; if observations were infeasible due to adverse weather conditions such as dense fog, heavy rainfall, or heavy snowfall, the observation schedule would be postponed.

Glacier mass balance is defined as the algebraic sum of surface accumulation and ablation, reflecting the average elevation change of the glacier surface per unit area relative to the end of the preceding mass balance year. Based on field observation data, the single-point mass balance is calculated as:
$$b_n = b_s + b_i + b_{si}$$
where $b_n$, $b_i$, $b_s$, and $b_{si}$ represent single-point mass balance, glacial ice mass balance, snow mass balance, and superimposed ice mass balance, respectively.

The calculation results were plotted onto large-scale glacier maps and topographic maps, with ablation and accumulation values contoured within the contour interval at 50 m spacing. Additionally, the monthly water equivalent of ablation and accumulation measured by glacier stakes and snow pits at the 4700 m a.s.l. observation site was calculated.

The accumulation and ablation areas between each pair of adjacent contour lines were measured, followed by stepwise calculation of the net accumulation C, net ablation A, and mass balance B of the glacier's ablation zone. Spatial interpolation was implemented using ArcGIS software to generate accumulation-ablation contour maps, enabling the computation of the entire glacier's mass balance.

The annual net mass balance B of the entire glacier is given by:
$$B = sum b_i left( frac{s_i}{S_{ni}}
ight)$$
where $s_i$ is the projected area of two adjacent contour lines, $b_i$ is the average net balance of the area $s_i$, $n$ is the total number of $s_i$ intervals, and $S$ is the total area of the glacier.

3. Data Quality Description: The exposed height of glacier stakes at various locations was measured with a tape measure during observations, alongside the total stake height, thickness of superimposed ice, snow stratigraphy, and depth of contaminated layers, all units are millimeters water equivalent (mm w.e.). Most observations were conducted during the ablation season. During the observation period, some glacier stakes were tilted or covered by snow, resulting in valid data being unavailable.

4. Data Application Achievements and Prospects: This dataset can provide parameter calibration and validation for glacier dynamic models and simulation studies.