Weather Forecast = Mathematical Model

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Weather Forecast = Mathematical Model

by goelmohit2002 » Fri Mar 13, 2009 10:54 am
Hi All,

In the below question, the original answer is [spoiler]"B"[/spoiler]. Can somebody please help me understand how [spoiler]"B"[/spoiler] is correct in the question below.

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Meteorologists say that if only they could design an accurate mathematical model of the atmosphere with all its complexities, they could forecast the weather with real precision. But this is an idle boast, immune to any evaluation, for any inadequate weather forecast would obviously be blamed on imperfections in the model.

Which of the following, if true, could best be used as a basis for arguing against the author’s position that the meteorologists’ claim cannot be evaluated?
(A) Certain unusual configurations of data can serve as the basis for precise weather forecasts even though the exact causal mechanisms are not understood.
(B) Most significant gains in the accuracy of the relevant mathematical models are accompanied by clear gains in the precision of weather forecasts.
(C) Mathematical models of the meteorological aftermath of such catastrophic events as volcanic eruptions are beginning to be constructed.
(D) Modern weather forecasts for as much as a full day ahead are broadly correct about 80 percent of the time.
(E) Meteorologists readily concede that the accurate mathematical model they are talking about is not now in their power to construct.

Thanks
Mohit
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by S0laris » Fri Mar 13, 2009 12:52 pm
I was choosing between B and E, but the just decided to stick up for meteo-ists statement and to support it B is the best. Second part just confuse IMO.
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by ssilver0210 » Sun Mar 15, 2009 1:14 pm
I would say choice B here is correct. Focus on the conclusion.

It states that it is impossible to evaluate the claims made by meteorologists that a mathematically accurate model of the atmosphere will lead to greater precision in weather forecasting.

Choice B says that significant gains in the accuracy of mathematical models, are accompanied by gains in precision of weather forecasts.

If choice B is true, then we now have a basis for evaluating the effectiveness of increasing the accuracy of mathematical models. True, there might be some other variable leading to the increased precision of forecasts (causation question), but the fact that precision of forecasts is generally increased with accuracy of models, weakens the conclusion that there is no way to evaluate the effectiveness of these models.
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by goelmohit2002 » Mon Mar 16, 2009 11:48 pm
Hi Sean,

IMO "B" says in the past:

Higher precision in model = Higher accuracy in forecast.

But it does not say anything about the present or future conditions. Moreover "B" does not say that model is perfect. There might be imperfections in the model.

So why can't in future for Meteorologist claim for his/her wrong forecast that

"Whatever best could have been done with the Maths model that is provided by you...I had done my best....you have provided me imperfect software and that needs to be improved a lot....the condition due to which yesterday's wrong forecast happened was due to some XYZ variation at some PQR place at earth.....I could not have done better than this"

Thanks
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by ssilver0210 » Tue Mar 17, 2009 7:52 am
Mohit,

What this comes down to is that the conclusion is very strong. It says that there is no way to evaluate whether a mathematical model could aid in the accuracy of weather forecasts.

But, if, as B states, we have clear situations in the past in which more accurate mathematical models have been accompanied by clear gains in the accuracy of weather forecasts, then in fact we at least have a basis for evaluating these models (they appear to be relevant.) We don't have to have some clear indication that these models are perfect, anything like that, as long as they might perhaps be working, it weakens the conclusion which states that there is no way to evaluate them.
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by nicolette » Sun May 15, 2016 8:07 am
Well I feel B is the answer. I guess I'm right. If some expert could throw