Question

explain how temperature difference result in the movement of air



long answer plzz

Answer 1

The movement of air. movement of air caused by temperature and pressure of wind. This is a due to rotation Of the earth beneath The moving air, which causes of apparent deflection of the wild to the right in the notheron hemisphere and left in the southern hemisphere

Answer 2

3.1. Wind due to differences in pressure

Movement of air caused by temperature or pressure differences is wind. Where there are differences of pressure between two places, a pressure gradient exists, across which air moves: from the high pressure region to the low pressure region. This movement of air, however, does not follow the quickest straight line path. In fact, the air moving from high to low pressure follows a spiralling route, outwards from high pressure and inwards towards low pressure. This is due to the rotation of the Earth beneath the moving air, which causes an apparent deflection of the wind to the right in the northern hemisphere, and left in the southern hemisphere. Consequently, air blows anticlockwise around a low pressure centre (depression) and clockwise around a high pressure centre (anticyclone) in the northern hemisphere (see Figure 3.1). This situation is reversed in the southern hemisphere.

3.2. Wind due to differences in temperature

Wind caused by differences in temperature is known as convection or advection. The process of convection was described in lesson 1. In the atmosphere, convection transfers heat energy from warmer regions near the Earth's surface to regions higher up in the atmosphere away from the heating influence of the Earth's surface. Whereas convection is the vertical movement of air, advection involves the horizontal movement of air and heat energy transference.

3.3. Sea breezes and land breezes

Temperature differences at the Earth's surface occur wherever there are differences in surface substances. A dark tarmacked surface will heat up more quickly on a sunny day (i.e. absorb more solar radiation) than a grassy field. Similarly, along the coast, large areas of land heat up more quickly than adjacent sea water (water has a large heat capacity and is a good conductor of heat). Air near the land surface is heated by radiation and conduction, expands and begins to rise, being lighter than the surrounding air. This is convection. To replace the rising air, cooler air is drawn in from the surface of the sea. This is advection, called a sea breeze, and can offer a pleasant cooling influence on hot summer afternoons when further inland the heat may become oppressive.

Air above the sea sinks and is again pulled in over the land. The full sea breeze circulation is show in Figure 3.2. A very hot summer sun may cause a sea breeze of up to 15 mph along the coast, felt in decreasing strength 20 to 25 miles inland.

Since the sea breeze owes its existence to the enhanced heating of the land under the sun, it follows that at night, when the land cools faster than the sea, a land breeze may develop. In this case, it is air above the warmer surface water that is heated and rises, pulling in air from the cooler land surface.

3.4. Katabatic winds

Inland on clear nights when the surface looses considerable radiation, surface cooling serves to set up air movements wherever there are undulations of contour. As the air becomes colder, it contracts and sinks down as far as it can move, settling into hollows, drifting down slopes and blowing down mountain sides. Large scale air movements of this nature are called Katabatic winds.

3.5. Global winds

On a global scale, the same principle of temperature difference operates to develop the major wind belts. Large volumes of air rise over the equator where most solar radiation is directed, creating a demand for colder air from higher latitudes This however, is an oversimplification of the cause of global weather. The presence of large continental land masses and vast expanses of ocean introduce further complexities to the global air movements.