Generally, we consider that 10 cm of snow = 1 cm of equivalent water. But, following a number of paramters, this ratio can be great or less. But let us suppose that the ratio snow/water = 100cm/1cm (which is probably wrong), despite this very disproportionate ratio, it is impossible to show that Total precipitation >= Solid precipitation (snow) at dates where it snowed.
My questions are : What total precipitation means here? Isn't it the sum of solid and liquid precipitation? Why equivalent water of snow is always superior to total precipitation? Does total precipitation already take into account the water equivalent of snow?
Here is the link to the site where I got the data (you can enter an Airport name to get some data to see what is going on, if necessary): https://meteostat.net/en/
弄清楚了它正在做什么,比较结果的网站在布法罗机场与NOAA NOWData…12月26日和27日2020年它显示(将NOAA数据从英寸转换为毫米后):
date | MS Total Precip | NOAA Precip | NOAA新雪 | NOAA雪深 | 37.6 mm | 200 mm | 37.592 mm |
---|---|---|---|---|
410 mm | Trace | 406.4mm |
所以总精度是我所期望的,液态水当量,与NWS值匹配,我熟悉使用多年。
问题是你的气象观测仪站点给出了雪柱中的雪深度…因此,测量地面上有多少雪(在一天的早些时候拍摄……爱荷华州国家气象局网站建议在早上7点),而不是一天中落下了多少,你将无法从中计算出总降雪量(因为融化或缺乏和压实意味着你不能只计算差异……即使在这个日期,470毫米也只成为210毫米的额外雪深)
我猜这是在车站拍摄的事实上的数据,因为直接测量积累只能合理地在清扫干净的滑雪板上进行更频繁的测量,这与车站自动化相反,可能只在重要的机场和气象办公室现场进行?所以对于大多数地方,这是你所拥有的最好的直接数据:-(美国国家气象局也从雷达和站数据中生成降水 >和雪 >地图插值,但不确定世界上其他地方是否存在这样的数据集:-(所以不确定水文学家如何获得降雪数据,没有人去这些地方做长期的数据收集?必须从附近的站点插入或使用模型数据或类似的??< / p >