Orographic precipitation - The second precipitation producing mechanism is described as orographic, which means, 'related to mountains.' Prevailing winds or other moving masses of air may be forced to flow over mountain ranges. As the air rises on the windward side of the range, it is cooled at the adiabatic rate. If cooling is sufficient, precipitation will result. After passing over the mountain summit, the air will begin to descend the lee side of the range. Now it will undergo a warming through the same adiabatic process and, having no source from which to draw up moisture, will become very dry. A belt of dry climate, often called a rain shadow, may exist on the lee side of the range. Several of the important dry deserts of the earth are of this type.
Dry, warm foehn winds (Europe) and Chinook winds (northwestern North America), which occur on the lee side of a mountain range, may cause extremely rapid evaporation of snow or soil moisture. These winds result from turbulent mixing of lower and upper air in the lee of the range. The upper air, has little moisture to begin with, is greatly dried and heated when swept down to low levels.
Much orographic rainfall is actually of the convectional type, in that it takes the form of heavy convectional showers and thunderstorms. The storms are induced, however, by the forced ascent of unstable air as it passes over the mountain barrier.
Cyclonic precipitation - A third type of precipitation is cyclonic. This topic cannot be fully understood until the entire subject of cyclonic storms and fronts has been developed. It will suffice here to note that in middle and high latitudes much of the precipitation occurs in cyclonic storms or eastward-moving centres of low pressure into which air is converging and being forced to rise.
Locals hypothesize that the legacy of Italian blood and culture in Cologne, colonized by the Romans more than 1500 years ago, makes the people more jovial and lighthearted. Cologne is the largest city on the Rhine.
Kolsch is not only the dialect spoken here but, also the name of their own top-fermented beer. There are more than 4,000 pubs, restaurant's and brewery taverns in Cologne.
Unlike many of the world's large cities, Cologne, with a population of over a million, gets better every day, there are more things to do and see, more new and innovative buildings... more
Travel is an opportunity to learn, whether geography, languages, history or other subjects.
Cologne is situated on the beautiful Rhine River.