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<br />'50s, the wet period here in the '60s, and then you go out through the more recent type here, got the
<br />same curve, here's a dry period back here in the early 1980's, wet year, and then here we are right
<br />now at the end of 2002 actually, we're in our dry period, but again, nothing atypical. And this is
<br />true of all the stations, there's absolutely nothing unusual about our current situation. So I think
<br />the bottom message is that there's no reason we couldn't have another dry winter, it's happened in
<br />the past. We could have another dry two winters, three winters. And so I think one of the
<br />questions is, in terms of preparation, we have to anticipate that at some point, whether it's now or a
<br />decade from now, we are going to have these decade-long droughts, and we have to plan now, at
<br />this time, as to what we would do if we had another dry winter, for example. What if we have 2
<br />dry winters? We have to plan on that.
<br />
<br />_ - Is it fair to say that it is fairly typical thus far, and then if we have a bad snowpack next
<br />winter, we're all back to the '50s before we get anything similar to it?
<br />
<br />Roger - I agree. What I mean by being typical, means that it has happened in the last 100 years.
<br />Not even considering the paleo-record, which you know, in the 16th century there was a 50-year
<br />drought that occurred in Western North America.
<br />
<br />- My point is, we'll all have to be very careful about how we word that, because if
<br />there's any importance that came out of the California 6-year drought, was that they kept thinking
<br />it was going to be better next year. We've got to be really careful. We have people who could
<br />misinterpret that.
<br />
<br />Roger - I think that we have to plan for the worse case situation. Reduce our vulnerability. I
<br />agree. We shouldn't hope that it's going to be wet, we have to plan for it being dry. Let me make
<br />one last connent. There is... where we go into the summer, and there is some research that had
<br />suggested that drought can self-perpetuate. And there's a couple of reasons for that, and I think
<br />this could be particularly true here in Colorado, and one of them is, when you have less
<br />transpiration because the trees are stressed and they're irrigating less, and you're farming less, you
<br />have less transpiration of water to fuel thunderstorms, and that's been demonstrated quite a bit. So
<br />that makes a tendency for higher based thunderstorms if they do occur, because there's less water
<br />available, and then less rainfall falls out of them. The second one is, it's been very well
<br />documented by satellite that if you have more cloud condensation nuclei, the little particles that
<br />help form the cloud droplets, if you have more of them because of dust or fire, they over-seed the
<br />clouds and they tend to rain less too. And so, if you have a lot of dust storms, or you have a lot of
<br />fires occurring. . . the heat from the fires in their immediate vicinity of course can generate a
<br />shower or thunderstorm, but the dust itself, if it feeds in downstream to other storms, actually
<br />tends to inhibit rainfall, and so there are two things that tend to perpetuate a drought and only a
<br />large scale affects can overcome that, and Klaus will talk more about that, and maybe Bob.
<br />
<br />- Add Jack's connent to that list about the absence of return flow would be the most
<br />frequent concern at now.
<br />
<br />Roger - Any questions?
<br />
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