|[Note Guidelines] Photographer's Note|
It was a dark morning. It rained heavily the night before. The sunlight was not that bright. I hought I could get some shot of insects. But they were not arounf, but I saw these pearls. How beautiful, still coherence to a blade of grass.
Dew is water in the form of droplets that appears on thin, exposed objects in the morning or evening. As the exposed surface cools by radiating its heat, atmospheric moisture condenses at a rate greater than that at which it can evaporate, resulting in the formation of water droplets.
When temperatures are low enough, dew takes the form of ice; this form is called frost.
Because dew is related to the temperature of surfaces, in late summer it is formed most easily on surfaces which are not warmed by conducted heat from deep ground, such as: grass, leaves, railings, car roofs, and bridges.
Dew should not be confused with guttation, which is the process by which plants release excess water from the tips of their leaves
Water will condense into droplets depending on the temperature. The temperature at which droplets can form is called the Dew Point. When surface temperature drops, eventually reaching the dew point, atmospheric water vapor condenses to form small droplets on the surface. This process distinguishes dew from those hydrometeors (meteorological occurrences of water) which are formed directly in air cooling to its dew point (typically around condensation nuclei) such as fog or clouds. The thermodynamic principles of formation, however, are virtually the same.
Sufficient cooling of the surface typically takes place when it loses more energy by infrared radiation than it receives as solar radiation from the sun, which is especially the case on clear nights. As another important point, poor thermal conductivity restricts the replacement of such losses from deeper ground layers which are typically warmer at night. Preferred objects of dew formation are thus poor conducting or well isolated from the ground, and non-metallic or coated as shiny metal surfaces are poor infrared radiators. Preferred weather conditions include the absence of clouds and little water vapor in the higher atmosphere to minimize greenhouse effects and sufficient humidity of the air near the ground. Typical dew nights are classically considered to be calm because the wind transports (nocturnally) warmer air from higher levels to the cold surface. But, if the atmosphere is the major source of moisture (this part of dew is called dewfall), a certain amount of ventilation is needed to replace the vapor that is already condensed. The highest optimum wind speeds could be found on arid islands. If the wet soil beneath is the major source of vapor, however (this part of dew is called distillation), wind always seems to be adverse.
The principles of dew formation do not strictly constrict its occurrence to the night and the outdoors. They are also working when eyeglasses get steamy in a warm, wet room or in industrial processes. However, the term condensation is preferred in these cases.
maurydv, jusninasirun has marked this note useful
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molto particolare questa macro con uno studio di forme e colori di tipo pittorico astratto, molto piacevole la composizione e gradevole impatto visivo.
- [2008-10-06 21:28]
What can I say about this one, it's just too much. Once again simple but refreshingly beautiful. color maybe a little pushing the edge on saturation, but I will let is slide on this one.
simple shapes form such a beautiful shot! nice composition
- [2008-10-09 2:36]
this is a beautiful artistic photo. i like that you chose to overexpose the drops.
Ever macro lens owner should try this capture of the drop. The coercion of the droplets and the surface tension making the subject stunning. With the suitable angle, it can turn into an amazing fisheye lens. Very graphical in pleasing green hues. Well done and thanks for sharing. Best regards.
Sunday October 12, 2008