Building a Better Virtual Raindrop

Jun 26, 2005
Building a Better Virtual Raindrop

A new way of mathematically modeling the formation of rain drops in clouds may improve our understanding of Earth’s climate, cloud formation and movement, and the effect that small airborne particles have on rainfall. In a paper published online by Geophysical Research Letter the week of June 20, 2005, atmospheric physicist Yangang Liu and atmospheric chemists Peter Daum and Robert McGraw of the U.S. Department of Energy’s Brookhaven National Laboratory present a new model, which, they say, helps to overcome some of the shortfalls of previous approaches.

In the first step in the formation of raindrops, small cloud droplets combine to form larger drops in a process known as autoconversion. The mathematical representation of this process is used in simulating cloud activity and global climate patterns. But according to the Brookhaven team, the model used previously has been oversimplified and vague because some of the terms in the equation lacked a physical basis.

To address this problem, Liu and his colleagues developed a new model for autoconversion that takes into account the limited size range of droplets that interact to create raindrops. The new model also accounts for the amount of liquid water present and the concentration of droplets in a cloud. The authors assert that their model avoids guesswork by being more grounded in physics and is as easy to use as other models.

This work was funded by the Atmospheric Radiation Measurements Program and the Atmospheric Sciences Program of the Office of Biological and Environmental Research within the U.S. Department of Energy’s Office of Science.

Source: Brookhaven Lab

Explore further: Small business owners not always worried about being treated fairly, researcher finds

add to favorites email to friend print save as pdf

Related Stories

Warm US West, cold East: A 4,000-year pattern

Apr 16, 2014

Last winter's curvy jet stream pattern brought mild temperatures to western North America and harsh cold to the East. A University of Utah-led study shows that pattern became more pronounced 4,000 years ago, ...

Asian air pollution affect Pacific Ocean storms

Apr 14, 2014

In the first study of its kind, scientists have compared air pollution rates from 1850 to 2000 and found that anthropogenic (man-made) particles from Asia impact the Pacific storm track that can influence ...

Appearance of night-shining clouds has increased

Apr 10, 2014

(Phys.org) —First spotted in 1885, silvery blue clouds sometimes hover in the night sky near the poles, appearing to give off their own glowing light. Known as noctilucent clouds, this phenomenon began ...

Recommended for you

Bloody souvenir not from decapitated French king: DNA

3 hours ago

Two centuries after the French people beheaded King Louis XVI and dipped their handkerchiefs in his blood, DNA analysis has thrown new doubt on the authenticity of one such rag kept as a morbid souvenir.

Residents of 'boom time' suburbs face unsustainable commutes

5 hours ago

People living in the 'boom time' suburbs of Dublin are more likely to endure unsustainable commutes to work than those living in older accommodation. Research shows that people living in newly constructed housing in the Greater ...

User comments : 0

More news stories

Cell resiliency surprises scientists

New research shows that cells are more resilient in taking care of their DNA than scientists originally thought. Even when missing critical components, cells can adapt and make copies of their DNA in an alternative ...