我正在试图了解城市环境中积雪中的融水是如何流动的。< / p >
I understand that for routing rain water, one can create grid and then determine the flow direction for each cell by using the D8 model. In the D8 model, first the slope for each of the 8 adjacent cells is calculated and then the direction of outflow corresponds to the direction of maximum slope. One can also compute the velocities with some approximations of the St. Venant equation.
I was trying to understand if it makes sense to use this model when :
- Runoff is because of snow melt in the absence of rainfall.
- Runoff is generated because of a rain over snow event.
Using the D8 model would mean that, in both of these cases, the snow melts, water percolates down the snow pack, and when it touches the land or water mass, the routing happens according to the current slope values.
Is this a reasonable way to characterize the meltwater flow?
If not, is there any literature where this problem is solved using any alternate technique?
- 横向流入SHE陆地上
- 横向流入SHE饱和区
- 横向流入SHE陆地上排水
- 横向流入SHE饱和区排水
我试图估计有多少水进入我正在研究的模型域的不同流域。然而，我不太明白这四个变量之间的区别，特别是“陆上”与“陆上排水”和“饱和区”与“饱和区排水”之间的区别
是否有任何简单的模型来近似土壤湿度水平(%)作为与水体(例如湖泊)距离的函数?如果一个人将湖的饱和水平指定为100%，那么是否有任何近似值可以用来确定距离湖中心x处的陆地的饱和水平?我知道这些计算将取决于天气和其他参数，例如土壤类型
我有一个地方的24小时总降雨量的信息，100年一遇的风暴事件。(来源:https://hdsc.nws.noaa.gov/hdsc/pfds/index.html)。我想利用这些信息创建一个真实的24小时内降雨的时间序列，以10秒为增量。
我怎么才能做到这一点?我可以假设均匀分布，这很天真。关于什么样的分发是合适的，有什么指导方针吗?< / p >
根据我的理解，你可以将上述术语定义为:
<强>大气灾害 -引起或影响天气或气候的灾害。例如龙卷风和飓风。<强>地质灾害 -由陆地或构造板块引起或影响的灾害。例如地震和山体滑坡。< / p >
So what would you class flooding as? It seems to fit either or in some cases neither.
Climate Fresk是一个非政府组织，发布了一款旨在教育人们关于气候变化的纸牌游戏。卡片33(第16页这个pdf文件)读(强调我):
气旋和大气波带来风，波浪和低压条件。1百帕斯卡的压力下降导致海平面上升0.4英寸。因此，飓风会导致海洋淹没(或沿海洪水)，并被已经由海平面上升引起的海平面上升放大。
压力下降和海平面上升之间真的有关系吗?如果有，是什么关系，背后的机制是什么?我觉得很难相信，因为水的压缩性非常低，所以我不明白大气压力的下降，即使是很大的下降，会导致海平面上升。气候Fresk项目声称其所有事实都来自IPCC的报告，但我不知道从哪里开始挖掘……< / p >
(PS: I'm not questioning the need to educate people about climate change, nor the integrity of the Climate Fresk project; I just want to get the facts straight.)
A < A href="https://www.google.com/maps/place/Miyazaki，+Miyazaki+Prefecture，+Japan/@31.7825779,131.2343451,187m/data=!3m1!1e3!4m2!3m1!1s0x3538b5f6c768a27b:0xd4ce23b1878ee7d!6m1! "1e1" rel="nofollow noreferrer">Google satellite view shows an unusual structure on a hillside in Miyazaki Prefecture, Japan (Latitude 31.782600°N, Longitude 131.233881°E):
It measures about 170m by 120m and is structured in steps of around 10m, with some parts also showing a grid structure on a scale of around 2m. It appears to be made out of concrete. What could its purpose be?
普吉特海湾地区夹在太平洋和Cascades之间…你会认为所有的雨水(和温暖月份的积雪融化)，低地地区会有灾难性的山洪暴发，在俄克拉荷马州看到的震级(1， 2， 3)，德州(1， 2， 3，4)或田纳西(1， 2， 3)。< / p >
On the contrary, western WA is actually subject to droughts and wildfires, not something you'd expect from such a wet region with rainforests.
这可能吗?需要多少水?整个地球需要被淹没才能达到那样的高度吗?< / p >
政府在今年剩下的时间里就没有什么可以做的来防止和减少损害吗?有没有像这样的地方，多年来成功地将损害降到最低?< / p >
I believe the loss of life and property is too high and happens every year or so hence investing in solutions must be a good choice still we don't see it happening at a large enough scale to make a difference is it due to unwillingness of the bureaucracy?
提前谢谢你
我正在试图找到关于美国洪水事件的实时信息，理想的多边形格式。到目前为止，我找到了两个来源:
- USGS洪水观察:洪水传感器所在的点和当前的测量值。这看起来很全面，但不包含多边形。美国国家海洋和大气管理局天气警告:洪水观察区域的多边形，但我不认为这是美国所有地区的全面。
是否有其他实时多边形数据集?我想知道观测到的洪水事件。< / p >
It's easy to get a statistical distribution that does not have finite variance. For example, you can sometimes get that when the thing that is measured comes from two random variables, one divided by the other. Sometimes you can't measure a variance. Sometimes you can get a statistical distribution that doesn't even have a mean.
When that happens, if you don't notice, you can get a mean and standard distribution from the data. And when you collect more data it will seem to mostly fit. But you get big outliers more often than you'd expect. As you recompute your mean and standard deviation, with more data the standard deviation keeps increasing. Because the longer you keep measuring, the more unexpected events you will have that go outside the predicted range.
Without knowing much at all about floods, they seem to fit this pattern. The news keeps announcing floods that were supposed to be unlikely, unexpected.
Of course, for all I know this is just the news reporting things that should have been expected. Of all the thousands of places we calculate hundred-year-flood levels for, every year we should expect floods that high at one percent of them. Maybe what's happening is really exactly what should be expected.
But it's testable. With enough data you can check whether flooding ought to fit a finite-variance distribution or not.
How well has it been tested?
In either case, it is assumed that vast amounts of water formed the gigantic chasm; the main difference being: over how much time did the transformation occur?
If a global deluge were accepted as a possibility, is the condition and appearance of the Grand Canyon consistent with such an origin?
对我来说，这没有任何意义。如果风减弱了，洪水完全是由潮汐效应引起的，这是天文事件，它不应该在几个月前，甚至几年前就被预测到吗?< / p >
我正在寻找任何关于大小盆地集中时间的学术参考(即文章)。< / p > < p >。我预计，与小盆地相比，如果两个盆地的降雨量相同，那么一个大盆地(面积为1,500 km^2)将在较晚的时间(例如1-2天后)发生洪水(或达到最大峰值流量)
描述
洪水和泥石流都是偶发事件，破坏力非常强。< /强> < / p >
Question
(Hopefully after the edit the question is more clear)
What is the difference between a flood and a mudslide?
我不知道接下来要去哪里。你知道到哪里去寻找更多的信息吗?< / p >
However, I have not found any statements on how high the storm surged ocean-wise. I've seen plenty of homes wiped off of their foundations from wind, but if you look carefully homes right next to them are still quite intact. My guess is the max "surge" was less than 1 m (<2 feet). Does anyone know this or where to find it?
Obviously detailed hydrological models are the only way to properly incorporate the varied topography and other unique factors in each situation.
But it would seem useful for a lot of folks, whether tens of miles downsource of a mountain stream (such as might've been vital as the Big Thompson flood started), dozens of miles down a valley from a dammed waterway (like those further down the Feather/Sacramento Rivers tonight), or hundreds of miles down a flooding major river (such as the 1993 Mississippi Flood), especially given the varying warning networks in place around the world, to have a rough scale of how quickly an unexpected flood might translate downstream their way. Is it a matter of hours, days, weeks? A rough worst-case scenario of how quickly they may have to react is what is desired.
Would seem a reasonable formula for a loose estimate might reasonably include the volume of water flowing, the expected channel size, and the elevation change (or alternatively, just the speed of the water... but if you knew that, you really don't need any special formula!).
Does such a formula like this exist?
Or are there good empirical estimates for those different situations I presented?
Or is each case just so unique that there's no hope of such an estimate?
特别是说:“较低的温度减少了蒸散作用，增强了湿润的土壤条件，减少了土壤入渗，促进了水的径流，最终形成了河流峰值流量”。你知道这事吗?< / p >
Based on this account, my questions are:
Given the amount of water on Earth (including all the water as liquid, solid, and gas, in all possible places: the atmosphere, the surface, and underground), is there enough water to flood the whole earth until ‘all the high mountains… were covered’?
What is the estimated rainfall intensity based on this description, and how intense is it in comparison with today’s rainfall intensity in tropical areas?
Regardless of the veracity or otherwise of the account, this makes for an interesting thought experiment.
此问题不涉及具体区域。这个问题是以一种构建世界的心态提出的，我只是想弄清楚周期性洪水是如何工作的。< / p >
气候变化有可能通过飓风强度(震级和强度)和海平面上升来增加洪水。世界各地的许多社区已经暴露在热带气旋造成的沿海洪水中。与气候变化相关的变化会在多大程度上加剧沿海洪水?我知道这在很大程度上是特定于地区的，但我想知道有哪些研究量化了这些影响