Storms :: essays research papers

If you know where and when to look, you cantreat yourself to a noisy display of atmospherichaloes, spots and pillars. These images can tell yousomething about the clouds budget items and possible turns in the weather. All of these images atomic number 18created by take fire reflect with cirrostratus clouds.These clouds occur at an altitude of 6,000-12,000metres. They appear as a thin sheet or storey(strata) that is pure white. The grade of cloud is sothin (only 100-450 metres) that is doesnt obscurethe fair weatherbathe or moon, so you should be able to decideyour shadow. Cirrostratus is made of many typesof trumpery crystals. However, four crystal shapes areresponsible for producing most of the parklandlysee haloes-plate crystals, columns, cappedcolumns and bullets. The most obvious halo isfound around the solarise. If the layer of cirrostratus isextensive, youll see an entire ring. Within the layerof cloud, sunninesslight is strike and passing throughthe slopes of randomly-oriented ice crystals. As thesunlight passes through each crystal, the lightchanges direction, or refracts. The radius of thehale depends on the amount of change in thedirection of the suns light. Usually this is 22degrees. Since the sun is 1/2 of a degree across,the radius of the halo is 44 sun-widths.Occasionally you whitethorn see a second halo at 46degrees from the sun (that is, with a radius of 92sun-widths). This is produced by sunlight passingthrough both the side and bottom of each crystal.Moonlight will alike produce a halo, around themoon, with the proper layer of cirrostatus.another(prenominal) common optical effect is known as " treatsuns" or "sun dogs" or "parhelia" (Greek for "withthe sun"). These bright spots on either side of thesun, outside of the halo, occur when sunlightpasses through the sides of capped columns,bullets and plate crystals, when these crystals arearranged with their sides vertical. The crystalswobble, diff using and smearing the colours of themock sun. You can see haloes and mock sunsmore clearly if you block out your view of the realsun by holding your hand in front of it at armslength. Another spectactular optical effect is thesolar pillar. This is a vertical shaft of light the samecolour as the sun stretching upwards from the sunand is most often seen at sunset or sunrise. Itsproduced by sunlight reflecting of the base of plateand capped column crystals in the clouds.