# Describe the relationship between air pressure and wind speed

### Earth Science - New York Regents June Exam - Questions 68 - 71 (Part C)

Answer: The relationship between air pressure and wind is that air from areas of In weather we can this the pressure gradient force or PGF. Wind pressure is the force of the wind nlowing against something. Air pressure is the wieght of the atmosphere. Imagine a column of air 1 inch by 1 inch and. The four elements of weather -- temperature, air pressure, wind and moisture -- interact with one another. For example: Surface temperature.

Air lower in the atmosphere is more dense than air above, so air pressure down low is greater than air pressure higher up. Remember those acrobats; there's a lot more pressure on the one on bottom than on the one on top. Temperature also makes changes in air pressure. In cold air, the molecules are more closely packed together than in warm air, so cold air is more dense than warm air.

Rising and Sinking Air Since warm air is less dense and creates less air pressure, it will rise; cold air is denser and creates greater air pressure, and so it will sink.

When warm air rises, cooler air will often move in to replace it, so wind often moves from areas where it's colder to areas where it's warmer.

## Severe Weather

The greater the difference between the high and low pressure or the shorter the distance between the high and low pressure areas, the faster the wind will blow. Wind also blows faster if there's nothing in its way, so winds are usually stronger over oceans or flat ground. Meteorologists can forecast the speed and direction of wind by measuring air pressure with a barometer.

Wind Direction Although wind blows from areas of high pressure to areas of low pressure, it doesn't blow in a straight line. Mathematics of gradient The high to low force that causes wind and its velocity works on synoptic scales such as those depicted on conventional surface maps.

Gradients can also occur on scales much smaller than the high and low systems associated with middle-latitude systems. One example is a microburst which occurs within an individual thunderstorm. A microburst is a vertical pressure gradient caused by existing dry air beneath or entering the thunderstorm. Rain evaporates in this dry air causing cooling. Cool air is denser, thus creating higher-pressure air that plunges to the surface.

Sciencing Video Vault Geographic Scale The high to low force that causes wind and its' velocity works on synoptic scales such as those depiction on conventional surface maps.

Wind and Air Pressure

In weaker cyclones, the clouds may cover the circulation center, resulting in no visible eye. The eyewall is a circular band of intense convection and winds immediately surrounding the eye.

It has the most severe conditions in a tropical cyclone. Intense cyclones show eyewall replacement cycles, in which outer eye walls form to replace inner ones.

### What is the relationship between air pressure and wind? | Yahoo Answers

The mechanisms that make this occur are still not fully understood. In the eyewall replacement process, the eyewall contracts to a smaller size, and outer rain bands form a new eyewall. This new eyewall weakens the original, and eventually replaces it completely.

During the replacement cycle, the storm weakens, sometimes dramatically, but afterwards the storm will often be stronger than before.

Outer or Spiral Rain Bands: Focussed areas of low level convergence, rising motion, and heavy rain that rotate counterclockwise around the storm.

These may extend hundreds of kilometers from the storm's center. The spiral rain bands are basically aligned with the low level winds which rotate counterclockwise and spiral inward toward the storm's center. The upper levels of a tropical cyclone feature winds headed away from the center of the storm with an anticyclonic clockwise rotation.

Winds at the surface are strongly cyclonic, weaken with height, and eventually reverse themselves. Tropical cyclones owe this unique characteristic to the warm core at the center of the storm.

Relationship between surface air pressure and windspeeds Surface atmospheric pressure in the center of a hurricane tends to be extremely low.

• What is the relationship between temperature, air pressure, wind and moisture?
• What is the relationship between air pressure and wind?

The lowest pressure reading ever recorded for a hurricane typhoon Tip, is millibars mb. However, most storms have an average pressure of millibars. Wind speed in a hurricane is directly related to the surface pressure of the storm. The graph below shows the relationship between surface pressure and sustained wind speed for a number of tropical low pressure systems.

This is a rather old figure and does not contain data from hurricanes after For historical perspective, the table below shows that hurricane Katrina was the sixth strongest hurricane ever located in the north Atlantic Ocean and the third strongest to hit the United States at the time of landfall at least since reliable meterological measurements have been available. Relationship between surface pressure and wind speed for a number of tropical low pressure systems.

Tropical low pressure systems are classified as hurricanes when their pressure is millibars or lower, and sustained wind speeds are greater than kilometers per hour.