NASA Appleman Chart - Real contrail science

reply to post by sandwiches


The papers support my claims.

Meteorology is a whole lot more than just a single, out dated graph.

Again, you wanna talk science, you gotta walk science.

Or in this case, read the science.

To ignore these papers is a clear sign of closed mindedness and an unwillingness to challenge your beliefs.

[edit on 1/6/10 by Chadwickus]

reply to post by Chadwickus

The papers do not support your claims. As stated n the OP, The science was reviewed in 1992 because the prediction of YES contrails by the appleman chart is only 25-35% accurate.

The papers you present are based on improving on prediction of YES contrails NOT improving prediction of NO contrails.

Making sense yet?

I wonder what OzWeatherman has to say about this. He doesn't dispute the accuracy of the appleman chart.

reply to post by sandwiches


Dude, seriously.

Stop pretending to know what is in these papers!

You wouldn't be saying what you're saying if you had actually read them.

Your 1992 contrail forecast document has been superseded numerous times over.

One of them is the Schrader teqnique, which can be found HERE.


Then, by THIS ONE

One of the three studies I provided earlier.

It further proves that you didn't even read the abstract that I quoted, because in that abstract it states:

The statistical model produced a correct diagnosis of contrail occurrence or nonoccurrence for 85% of the observations, as compared with 58% correct for the Schrader technique, for this particular dataset.

To further elaborate (this means reading the sources provided):

This dataset of nearly coincident radiosonde observations and aircraft observations was used to test the Schrader (1997) contrail forecast algorithm, which is very similar to the operational AFWA (Air Force Weather Agency) contrail forecast technique (JETRAX), and to develop a new statistical regression-based contrail forecast algorithm. The Statistical Contrail Forecast Model was developed, which makes use of logistic regression techniques to relate contrail-yes/contrail-no observations with nearly coincident radiosonde measurements. In this study,flight-level temperature and relative humidity parameters were found to be the most important predictors. The Statistical Contrail Forecast Model provides results that are superior to the Schrader (1997) contrail prediction algorithm. The statistical model produced a correct diagnosis of contrail occurrence or nonoccurrence for 85% of the observations, as compared with 58% correct for the Schrader 40/70/10 algorithm. The probability of detection of contrail occurrences (POD/Y) was 0.91 for the statistical model and 0.35 for the Schrader 40/70/10 algorithm. The results for the Schrader (1997) algorithm presented here are consistent with past Air Force contrail studies that document the tendency of past and present AFWA techniques to underpredict the occurrence of contrails and overpredict the nonoccurrence of contrails.

The Appleman figures are clearly unreliable.

Therefore your claims are void.

reply to post by Chadwickus

Why are you comparing numbers and percentages that combine both prediction of YES contrails and NO contrails?

Are you blind to see that these new methods were developed simply to better predict YES contrails?

Do you understand that the appleman chart remains 98% accurate at predicting NO contrails?

Thanks

Personally, I find the -35C requirement just fine to prove the existence chemtrails, but altitude requirements can be further brought much higher by considering pressure and humidity.

By studying the science and atmospheric sounding data, anyone will agree that contrails never form below about 10,000 ft. Therefore, when you see a "contrail", take its altitude. If it's below 10,000 ft you have a chemtrail.

What could be simpler?