The air in motion is called wind, it is invisible yet we see evidence of it nearly everywhere we look. It sculptures rocks, moves leaves blows smoke and lifts water vapor upward to where it can condense into clouds and form precipitation, in form of rain. The wind is with us wherever we go. On a hot day it can cool us off, on a cold day, it can make us shivers. A breeze can sharpen our appetite when it blows the aroma from local bakery in our direction that is the power of the wind. Therefore the wind is a powerful element among the common elements of weather we are conversant with in meteorology, the likes of, precipitation, pressure, humidity, sunshine, in fact, wind makes the weather in motion, a dynamic system. I can call it the work-horse of our weather; it moves storms and large fair-weather systems around the globe, like monsoon and tropical cyclones. It is also responsible for the formation of tornados together with dust devils, plus many other common phenomena. Wind transports heat and moisture, it is the one responsible for the seasons we experience in our regions, either summer or winter and also drought or rainy seasons. Also, wind transports dust and pollen grains from one area to another. It is responsible for the outbreak of diseases, when it changes its course and transport bacteria from one location to another.
Wind is the very best friend of pilot and again a very big enemy of the pilot. For the aircraft to take off, the presence of wind and to be specific its strength is very important. For the aircraft on the run way to make it up, the strength of the wind matters a lot to the pilot. And again at its cruise when the wind moves along the direction of aircraft but not against, it is quite economical, since it will burn few amount of fuel, within a long flight made for the short time, for example when a commercial plane moves along the Jet stream (a strong narrow current of air).The other face of wind is the enemy of the pilot, when the plane goes against it, there is formation of turbulence, like during the downburst (rapid descend of air).
So what is wind? This is a very powerful weapon that must be handled carefully so as to use its benefits and also to take cautions about its harmful consequences. By the way that’s the work meteorologists do almost the entire of their carrier, to monitor the movement of wind systems, and use them to predict the weather of the place. So for a good meteorologist he or she have to know all the global and local wind, their prevailing pattern and their origins, for your information, winds gets their names from their origins, good example is westerly wind, wind moving from west to east, and easterly wind from east. Winds veer to the right in the northern hemisphere and to the left in the southern hemisphere, reason? Because of what is called Coriolis Effect (this is the force experienced by the wind due to the rotating earth). Two winds can meet, when they do they form zones, good example is Inter-tropical convergence zone (ITCZ). This again is responsible for the seasons of regions it crosses. Wind can be a synoptic, messoscale or micro scale; it depends with the time duration it takes for the wind to blow in a direction and the space it covers. For example synoptic wind systems can take up to 6 months, and cover a distance of 200km; mostly they are global general circulations.
So what causes wind? Due to strong differential heating of the sun, high temperature regions and low temperature regions are formed; this is responsible for the pressure gradient. Since, high temperature regions are of low pressure and low temperature regions are of high pressure. This will make wind to move along that gradient, driven by the force known as, pressure gradient force (PGF). This explains why the wind is sometimes so strong in the afternoon when we have highest temperature and very calm nights, when the temperatures are relatively low. Finally, I can now give my last definition to this horse-power of our weather as, flowing of air mass from the region of high pressure to the regions of low pressure.
AUTHOR: OTIENO DANCUN ONYANGO, (third year meteorology student) danji239@gmail.com.
