# Relationship of air pressure and wind speed

### Statistical Analysis of the Relationship Between Wind Speed, Pressure and Temperature

The wind blows because of differences in air pressure from one location to the speed and direction of wind by measuring air pressure with a barometer. An Ideal Gas behaves in such a way that the relationship between pressure The Pressure Gradient Force (PGF) is the direct result of different air pressures. Hence, if we assume the mass and density of the air are constant, then wind speed is directly proportional to pressure, a ∝ ΔP and w ∝ P. This.

One climbs up and stands on another's shoulders. The weight of the acrobat on top puts more pressure on the one below.

### Wind & Air Pressure

Then another acrobat climbs up and stands on the second acrobat's shoulders. Now there's even more pressure on the acrobat on the bottom because he is under the weight of the two acrobats above him. It's the same with air. Yes, air has weight, and probably more than you think.

## Windy Weather II: The Correlation Between Barometric Pressure and Wind Velocity

In fact, the weight of the air on your desk at school weighs about 11, pounds. That's about the same weight as a school bus! Since air pressure pushes in all directions, the air pressure pushing up from under your desk balances out the air pushing down on it, so the desk doesn't collapse under the weight.

Just like an acrobat with two people stacked on his shoulders would want to move to where there wasn't so much pressure on him, air moves from areas where the pressure is higher to where it is lower. Gradients can also occur on scales much smaller than the high and low systems associated with middle latitude thunderstorms.

Cool air is denser, thus creating higher pressure air that plunges to the surface.

Precise Relationship Wind velocity is determined by pressure gradient, so what magnitude of gradient corresponds to a certain wind velocity? According to The Weather Book by Jack Williams, a "half pound per square inch pressure difference between places miles apart will accelerate still air to an 80 mph wind in three hours. This is difficult to be precise because other factors such as friction, the Coriolis effect, and "spin out" and latitude affect speed. An example from metservice.

Downward vertical motion can happen with low flowing to high. However, there is a smaller standard error, this is an indication of higher order terms in at least one of the principle factors to explain the curvature seen in the residuals Fig. Full second order model: Consider the augmented model: Scatter plot of pressure versus wind speed including developed model including interaction Using this non-response analysis, we have to be: Residual plot of a pressure and b wind speed Solving for pressure we have: The apparent reason for the two solutions is that pressures relationship to wind speed is indirectly related by temperature and volume and therefore, the pressure would be different before, during and after a storm.

Scatter plot of pressure versus wind speed including developed model including higher order terms and interaction This is seen in the estimates when we let: This is an indication that there are lurking variables, either volume not measured or temperatures not provided in this data set are related to pressure and wind speed. This breakdown is consistent with the Wooten and Tsokos b scale, that around 80 knots there is a shift in pressure differentials and the start of hurricane category 2 in this newly defined scale.

Scatter plot of pressure versus wind speed a before the storm and b after the storm Table 4: Standard scores for wind speedpressure, temperatures atmospheric, water and dew point for a the original data and b for the day moving average In the Saffir-Simpson scale, this shift occurs at 85 knots.

As these values vary from hour to hour and have daily and yearly patterns, Fig. To compare these measures near the surface to those measured within a hurricane; consider the non-response model given in Eq.

Using this non-response analysis and the raw data, we have to be: Solving for pressure in terms of wind speedwe have Hence, solving for pressure as it has been done in the previous analysis, Eq.

However, as the wind speed increase, this estimate has increase variance. Figure 8 indicates that there is more to the relationship between pressure and wind speed near the surface of the water in the Gulf of Mexico.

## Severe Weather

This is seen in that the estimates for pressure are only accurate during the summer months when temperatures are higher. However, in the winter months, the developed model does not accurate estimate the observed pressure.

This is due to the affects of temperature. By the ideal gas law, pressure and volume are directly related to temperature, but under the assumption that pressure is constant, by Charles Law Pidwirny,here the ratio of volume to temperature is constant.

Therefore, during the summer months when pressures appear to be constant, temperature should explain the interaction between pressure and volumes. To compare the behavior of each of the various temperatures and related volumes by scaling the data as follows: Among the variables given, pressure appears to be most constant; in addition, the behaviors of the three temperature readings are very similar.

This is seen in Fig. When compared to the other variables, temperature appears to relate inversely; when temperatures rise, pressure and wind speed compensate for the moving volumes of air. This measure is also an indication of the constant nature of the variable itself.