Probable Chance of Showers - Essay Example

Because of the above increased reliance on statistics and probabilities, the chances of wrong weather predictions are always there. This paper analyses how concepts used in probability theory are employed by meteorologist to determine when rain will rain in a certain region an how many inches.  In meteorological forecasting, the categorical forecast is one that has only two probabilities: zero and unity (or 0 and 100 percent). Thus, even what we call a categorical forecast can be thought of in terms of two different probabilities; such a forecast can be called dichotomous.

On the other hand, the conventional interpretation of a probabilistic, forecast is one with more than two probability categories; such a forecast can be called polychotomous (Probabilistic Forecasting - A Primer) Dichotomous weather prediction is more accurate than polychotomous prediction. In polychotomous prediction more probabilities are there compared to the dichotomous prediction and it is impossible to the public to know how much rain may rain or at what time the rain starts. In other words, polychotomous prediction is only an assumption which lacks scientific facts.

On the other hand, dichotomous prediction may have better scientific backing. It always says accurately whether rain comes or not at a particular period over a particular place. In other words, dichotomous prediction is 100% accurate. Dichotomous predictions are not always easy because of the changing climate cycles. Great uncertainties are prevailing in human life and weather prediction is also not free from uncertainties. Because of the increased element of uncertainties involved in weather prediction, probability theory is quite often used in weather prediction.

“Probability starts with logic. There is a set of N elements. We can define a sub-set of n favorable elements, where n is less than or equal to N. Probability P = n/N” (Theory of Probability: Best Introduction, Formulae, Algorithms, Software). In weather prediction, the favorable elements of rain are atmospheric temperature, humidity, pressure, cloud conditions etc. In other words, the above elements can determine whether rain happens or not at a particular period of time. When the number of favorable elements more, n > N and the probability becomes more than unity.

When probability is more than one or equal to one, the chances of rain are more. On the other hand in some cases, N might be the double of n. In such cases, the probability becomes .5 or the chances of rain become 50%. For example while tossing a coin, the probability of getting a tail and head is 50%. Here the attempt made or N is 1 and the coin has 2 sides or n is 2. So the probability p= ? or 0 .5. Probability theory is used based on the frequency of occurrence of events also. It is an accepted fact that during monsoon period, heavy rain will take place.

The arrival of rain during monsoon period has started long time back and it continues so. Weather or rain prediction during monsoon periods can be easy for the meteorologists by analyzing the frequency of occurrence of rain during the monsoon season. It is possible for meteorologists to analyze the rain data or statistics over a particular period of time and to predict the possible amount of rain which may happen in a particular year. All these calculations are made with the help of probability theory