Cycle
Is smog changing the face of Earth's water cycle?
In year 2000 satellite data showed that urban pollution was reducing the size of droplets inside clouds.
One effect was reduced precipitation from short-lived clouds in hilly regions. These clouds form when moist air rises above the hills and form raindrops. But they dissipate once they have passed over them, giving them a limited amount of time to drop their moisture.
The researchers were able to use this data as a measure of the amount of pollution in the air and then compare it to patterns of rainfall.
Hazy Days
To see how this was affecting precipitation, scientists looked at the difference between rainfall at a hill station. This latest research joins a growing number of studies showing the effect of pollution on the planet's water cycle.
Another study, shows that there are more intense storm systems over the Pacific ocean. By delaying the onset of rainfall, small particles in the air are apparently making storm systems over the Pacific larger before they eventually break.
Moreover, in January 2007 Stanford University, USA, showed that air pollution is reducing ground-level winds in California. This, in turn is reducing the amount of evaporation from the ground, lakes and rivers.
Conclusion is that we are changing the planet's water cycle in many ways: in the intensity of storms, in the redistribution of precipitation, by making clouds live longer and cover larger areas and by slowing low-level winds.
.
Cycle
Is smog changing the face of Earth's water cycle?
In year 2000 satellite data showed that urban pollution was reducing the size of droplets inside clouds.
One effect was reduced precipitation from short-lived clouds in hilly regions. These clouds form when moist air rises above the hills and form raindrops. But they dissipate once they have passed over them, giving them a limited amount of time to drop their moisture.
The researchers were able to use this data as a measure of the amount of pollution in the air and then compare it to patterns of rainfall.
Hazy Days
To see how this was affecting precipitation, scientists looked at the difference between rainfall at a hill station. This latest research joins a growing number of studies showing the effect of pollution on the planet's water cycle.
Another study, shows that there are more intense storm systems over the Pacific ocean. By delaying the onset of rainfall, small particles in the air are apparently making storm systems over the Pacific larger before they eventually break.
Moreover, in January 2007 Stanford University, USA, showed that air pollution is reducing ground-level winds in California. This, in turn is reducing the amount of evaporation from the ground, lakes and rivers.
Conclusion is that we are changing the planet's water cycle in many ways: in the intensity of storms, in the redistribution of precipitation, by making clouds live longer and cover larger areas and by slowing low-level winds.
.