你是对的,高空试探通常每天只做两次,甚至在相当粗观察间隔。这高空数据模型中绝对是非常重要的。首先,重要的是要注意,* *甚至广泛,非常朦胧的画面在空中表面* *帮助很大。可以看到在准地转方程ω。基本上大型涡度系统和喷射条纹驱动大气中空气的垂直运动。加上没有那么多的复杂地形引起的地面覆盖/湿度/微分加热表层看到。因为这些大规模的进化特性很简单的一天,清晨的上层预测仍然是相当可靠的和有用的6小时后。但这说,小规模shortwaves天气预报和涡度最大值绝对是至关重要的。和更小的尺寸和更瞬态性质,忽视他们的变化超过6小时可能真的对预测等关键的细微差别时你会看到龙卷风爆发或飓风追踪。所以实际上,* *我们认识到这些变化吗? Well, we do have a second source that these days is probably at least as important as soundings, perhaps even moreso - **satellite imagery**. See for example [this][1] satellite page. You can turn on HDW-low, HDW-mid, HDW-high. Well as far as I understand it, the models are ingesting that information readily. Likewise, clouds, which are just as important. I believe some satellites also have vertical sounders that are used more now. And third, **we also have some other data sources that help**. In certain parts of the world, we've got radars. I believe at least some of the better models these days are using that data... there's plenty of wind data to be had from velocities (though it would seem challenging to use/analyze it given things like range-folded velocities and the ambiguity of tangential winds [see the intro to [this article]][2]). And finally, I believe at least the ECMWF has had real success in ingesting [ACARS][3]... atmospheric data that are generally reported by all commercial aircraft. But... all that said, your point still has some potency. Especially when we note that, when it comes to our best model, the ECMWF... it still only runs twice a day. Maybe other reasons drive the decision, but you'd think they still weigh how improved such forecasts are. So it seems fairly likely that they've determined that long-range forecasts don't improve much when they are still based heavily upon that older information. But then, I think everyone would agree that having hourly models available like the HRRR is very useful in important nowcasting situations, such as severe weather awareness. So maybe the overlooked small data changes are (counterintuitively?) more important to long-range forecasting than short-term. Definitely an interesting question you've raised! [1]: http://www.ssd.noaa.gov/goes/east/tatl/h5-loop-vis.html [2]: http://www.nat-hazards-earth-syst-sci.net/6/285/2006/nhess-6-285-2006.pdf [3]: https://amdar.noaa.gov/FAQ.html