Outdoor air pollution is a complex mixture of several pollutants, the common sources of outdoor pollution are emissions caused by combustion processes from motor vehicles, solid fuel burning and industry.
They major classes of outdoor pollutants include;
Carbon monoxide; carbon dioxide, sulfur dioxide, nitrogen oxides, VOC's, SPM's, photochemical oxidants, ozone and PANs.
Evaporation of the water is the process that exerts the pull on water molecules that is relayed from leaf to root via cohesion. The pressure of the water present in the leaves becomes less due to evaporation of water. The pressure of water in the roots and lower part of the shoot is high. This gradient of pressure creates a pull on the water molecules present in the roots to move upwards to the leaves to occupy the vacant space. The whole process is called transpiration.
If a light is traveling straight up out of the ocean, then moves out of the air it will become less refracted because it is moving to a far less-dense medium, meaning the image will not be distorted.