What is related to pressure gradient

In contrast, with vascular or valvular stenosis the pressure gradient is increased because of the increased resistance to flow e. Furthermore, as flow increases across the stenotic lesion e. Increased flow across a heart valve, particularly when it is stenotic, causes a a large increase in velocity that can lead to a significant degree of turbulence , which will further augment the pressure gradient across the valve and lead to a functional murmur or enhance the intensity of a preexisting murmur.

Cardiovascular Physiology Concepts Richard E. Klabunde, PhD. Klabunde, all rights reserved Web Design by Jimp Studio. The Poles are at an angle, causing the sun's radiation to strike the North Pole and the South Pole at steep angles. The more normal the surface is to the sun, the brighter and warmer a region will be. The greatest warming is around the equator Fig. Clouds can create some variation; occasionally there will be greater warming somewhere besides at the equator.

But on the average near the Poles the heating is minimal and near the equator at a maximum. This accounts for the general circulation of winds on the planet.

The heating differences in turn create pressure differences. The cold air sinking at the pole would tend to produce higher pressure with cold air sinking to the ground. Low pressure would occur with rising air as air is accelerated away from the ground. The pressure differences cause winds to blow, trying to even out the pressure differences. These pressure differences are observed looking at pressure gradients. The difference in pressure produces a force called the pressure gradient force PGF.

It is defined as:. The strength of the pressure gradient force can be changed by increasing the pressure difference D P or reducing the distance D Z of the pressure change. When a pressure gradient force exists, the wind will attempt to balance the force by moving directly from high to low pressure Fig.

Authors Authors and affiliations Mark Binkley. How to cite. This is a preview of subscription content, log in to check access. Byers, H. General Meteorology. New York: McGraw-Hill. Google Scholar. Griffiths, F. Driscoll, Survey of Climatology. Columbus, Ohio: Charles E. Navarra, J.