Last week, my husband and I went hiking in Montana, looking for marine shelled fossils and birds along the way. We were in much the same place where we saw all the forest fires last year (see blog on Forest Fires).
This year, we found almost no fossils for several days. Yet, I took careful notes. Why?
- We thought there should be fossils there (our hypothesis).
- We didn’t find any (disproving our hypothesis).
So we learned something from the experience. From geologic maps, we can identify the type of rock (Bearpaw Shale). We knew that fossils form the nucleus of rocks called “concretions” in the Pierre Shale. There was Bearpaw Shale. There were concretions. But the concretions had no visible fossils.
From a personal point of view, this tells us not to expect to find too many fossils in this area.
From a geologic point of view, this poses the question – why are there so few? This fascinating question probably has a two-part answer. The first part involves where the creatures lived (Was the water too deep?). The second part involves whether the creatures were fossilized (Did the shells dissolve? Did they get crushed? Were the animals eaten?).
Null – or zero – results were also important in GLOBE’s past Contrail Count-a-Thons. If you see a contrail, and report it as “non-persistent”, “persistent,” or “persistent spreading,” that is valuable information. It tells us that there was enough water vapor for the contrail to exist. Indeed, the findings of former GLOBE PI Lin Chambers show – not surprisingly – that more humid air at jet altitude means longer contrails that can spread horizontally.
But a report of no contrails is interesting because it indicates very dry air – assuming that the observer is below where jets are known to be flying.
Another example of important “zero” observations is for precipitation. According to Nolan Doeskin of the Community Collaborative Rain, Hail, and Snow network, an observation of “no precipitation” is very important. “No rain” for a long period of time – or drought is significant information if you need water, which we all do.
Of course a “zero” observation doesn’t always mean that there is nothing there. As someone once said…
“The presence of absence doesn’t necessarily mean the absence of presence.”
One of the best examples of this involves life on other planets.
If I go to Mars and find no life, life could still exist there. Why? Because:
- I could have been in the wrong place (as in the fossil example).
- Or I could have not realized what kind of life I should be looking for.
- Or I could have been looking for it the wrong way. (maybe I needed a microscope, or some chemical test).
So if you are recording weather data for GLOBE, for CoCoRaHS, for some other organization, or for yourself – don’t forget to record the “boring” weather as well as the interesting weather.
