Our house is in the mountains. We have meadow below and forest above. The main windows face west so we look out at the high country. If you can see the mountains, the mountains can see you and that means wind. It's been windy all winter, such that we started to go nuts with it. When we walk in the forest by my house, the floor is crunchy under our feet. We'll worry about fire this summer.
My thoughts about rainfall have evolved over 20 years as my life has become ever more tightly bound with precipitation. So if you don't care about my personal history with rainfall, stop reading now. I'll write something else next time.
It started out for me as a simple concept: It's either raining or it isn't, right?
Not. It's a form of epistomology - how do you know what you know about rain? How do you know if it's raining behind you when you aren't looking there, or up in the mountains, or across town?
1693
OK, that's easy, put out a rain gage, collect the rainfall and then you'll know! You can measure rainfall by putting out a funnel that collects from a known area into a measuring container.
1974
But what if I'm not able to go out to the rain gage all the time and watch it? OK, use a two-part tipping bucket that fills up one side and tips over its center of gravity whenever it gets 0.01 inches of rainfall. Every time it tips it sends a radio signal, and we just count them to find out how much it rained. So now we know exactly what's going on, right now. Right there, just where the rain gage is.
(1978 - Husband's note to self: Develop custom software that runs on a microprocessor, records radio-transmitted data in real time so we can see what's happening, be able to print out rainfall results displayed on a map. Guess about the rainfall between the rain gages for the purpose of the map. Make sure Big Thompson flood doesn't happen in Boulder County.)
1988 - By the way, there's this new radar network from the National Weather Service called NEXRAD and it lets you see rainfall in the sky across a large area. Who needs rain gages?
1992
So we did rain gages. We started a company, DIAD, and we came up with ways to make automated rain gages more efficient, less expensive and more reliable. We developed processes and tools that are useful for putting in, maintaining and collecting data from rain gages, so we could see what was happening. At the rain gage.
(1994 - Husband's note to self: develop software package that runs in Windows because that's what people will have, records data in real time so we can see what's happening, display data on a map, be able to playback recent storms...save data in relational database for historical purposes. keep guessing about the rain between the gages, help customers mitigate their flood event.)
1994
Um, we still need rain gages. It turns out that: (1) NEXRAD reflects off whatever's out there, including geese, smoke, hail and large immoveable objects, so we're really estimating rainfall based on climate conditions and radar reflectivity, and reflectivity is strongly affected by raindrop size. (2) NEXRAD looks at the sky, but we really care about the consequences of rainfall which means it had to land on the ground somewhere. (3) NEXRAD is finally here, but it gives us the wrong answers sometimes - often - for what we need to know about runoff.
1998
This really smart guy Dave Curtis started a business, NEXRAIN, that used rain gage data to calibrate the NEXRAD rainfall estimates so we could have a much better idea of what rainfall reached the ground. This gives a much better input for runoff models than rain gage data alone, so when Atlanta contemplates rebuilding their sewers they'll know whether they have to spend $1 billion or $2 billion to do the job - it would be bad to plan for the wrong amount!
2003
So let's merge these two companies! Let's make something called OneRain that does all of the above - that's what people really need. Let's offer real-time 24/7 data services so rainfall data consumers get the information they need when and where they need it. We'll put it out on the web, we'll have maps and charts of rainfall, stream responses, weather related to rainfall, and everything.
2005
Note to self: Mergers are fun, and be sure you have the emotional fortitude to do it well!
2006
We still can't measure rainfall very effectively. We go to a great deal of physical and computational trouble to sense and then analyse the results, and there's no way of knowing what really happened so we can test the success of our methods. We can go to Mars with digital video, but it's a bear of a challenge to estimate accurately the rainfall that fell over some particular watershed (or the runoff, but that's yet another problem so don't get me started) .
The good news is I'm not bored yet. Get me a funnel, please. I'm going to put a plexiglass rain gage near the bedroom window so I can look out and see it when I get up in the morning. That way I'll feel better about the fire danger when the gage gets wet.
No comments:
Post a Comment