论文标题
北半球积雪的趋势
Trends in Northern Hemispheric Snow Presence
论文作者
论文摘要
本文开发了一种数学模型和统计方法，可以在存在/不存在雪覆盖的情况下量化趋势（而不是深度），并将其应用于1967 - 2021年期间从卫星天桥中提取的北半球观测值分析。引入了具有周期性动力学的两国马尔可夫链模型，以通过网格方式分析数据的变化。估计每个研究网格估计趋势，转化为每个世纪损失/获得的雪覆盖次数。这些趋势的不确定性边缘是从模型开发出来的，用于评估趋势估计的重要性。确定具有可疑数据质量的网格。在值得信赖的网格中，雪的存在的降雪量几乎是降低的两倍。尽管发现北极和南部纬度的积雪正在迅速退缩，但其他地点（例如加拿大东部）正在经历雪覆盖。
This paper develops a mathematical model and statistical methods to quantify trends in presence/absence observations of snow cover (not depths) and applies these in an analysis of Northern Hemispheric observations extracted from satellite flyovers during 1967-2021. A two-state Markov chain model with periodic dynamics is introduced to analyze changes in the data in a grid by grid fashion. Trends, converted to the number of weeks of snow cover lost/gained per century, are estimated for each study grid. Uncertainty margins for these trends are developed from the model and used to assess the significance of the trend estimates. Grids with questionable data quality are identified. Among trustworthy grids, snow presence is seen to be declining in almost twice as many grids as it is advancing. While Arctic and southern latitude snow presence is found to be rapidly receding, other locations, such as Eastern Canada, are experiencing advancing snow cover.
