Man made seawater particles change cloud brightness, temperature and rain patterns as shown by computer models, thus proving useful against global warming.

According to the research, new results from modeling clouds like those seen in shipping lanes reveal the complex interplay between aerosols, the prevailing weather and even the time of day the aerosol particles hit the air.

Phil Rasch, chief climate scientist at the Department of Energy''s Pacific Northwest National Laboratory in Richland, Washington, said," We''ve seen ship tracks affect the reflectivity of clouds."

He further added," We want to know if we can do the same thing when we want to, on purpose, and how that might be helpful in countering some of the effects of global warming. We decided to see how the reflectivity of clouds is influenced by particles in a very detailed model that treats clouds much more realistically than we are able to do in a typical climate model."

The group performed some exploratory computer simulations to determine the net effect of increased aerosols.

A few hundred miles southwest of Los Angeles, Rasch''s team simulated three ships chugging along in a 93-mile by 37-mile block of the Pacific Ocean.

The team showed that introducing additional particles into the model near the surface - as proposed for geoengineering - would make the clouds significantly more reflective than they would otherwise be, in certain situations.

Rasch will discuss other cloud, weather and climate characteristics affected by aerosols, such as how long the brighter clouds last, whether they burn off when the sun comes up, and what happens when they finally rain. (With Input from Agencies)