Sentences with phrase «by aerosol droplets»

«It seems that TB tricks the immune system into damaging our own lung tissue, which therefore makes the person highly infectious through coughing and the TB then spreads by aerosol droplets to other individuals.

Not exact matches

How much radiation is reflected by sulphur dioxide aerosols varies according to the size of the droplets, their height in the atmosphere, whether it is night or day, what season it is and several other factors.

By absorbing heat, aerosols can evaporate nearby cloud droplets — making the cloud less reflective and compounding the heating effect.

On their own, aerosol particles are tiny; when a cloud droplet becomes a rain droplet, it grows by a factor of a million as droplets crash and coalesce together.

Droplets from bursting bubbles are the principle means by which aerosols are produced above the open ocean, said first author Luc Deike, a Princeton University assistant professor of mechanical and aerospace engineering and the Princeton Environmental Institute (PEI).

Highly pathogenic avian influenza A / H5N1 virus can cause morbidity and mortality in humans but thus far has not acquired the ability to be transmitted by aerosol or respiratory droplet («airborne transmission») between humans.

A team of scientists led by Pacific Northwest National Laboratory atmospheric researcher Dr. Susannah Burrows and collaborator Daniel McCoy, who studies clouds and climate at the University of Washington, reveal how tiny natural particles given off by marine organisms — airborne droplets and solid particles called aerosols — nearly double cloud droplet numbers in the summer, which boosts the amount of sunlight reflected back to space.

Although most aerosols are carried up by the same atmospheric circulation patterns, their chemical and physical properties determine whether or not they become «cloud condensation nuclei,» which are the points around which droplets form before they become cloud droplets.

Aerosol spread (small droplets) is when the organisms which cause the disease are spread from the infected person via droplets in the air (caused by coughing, sneezing or during close conversation) and then inhaled by another person.

Dog Flu, also referred to as Canine Influenza or CIV, is highly contagious and rapidly spread by a combination of aerosols, droplets, and direct contact with respiratory secretions or contaminated fomites.

Transmission occurs via an aerosol - droplet route, direct contact, or possibly by contact with contaminated objects.

My question is: does the retroreflectivity of the larger droplets, i.e. back towards the light source, play into the sulfur aerosol issue or is it simply averaged out by the bulk effect of all the aerosol particles present in the apparently white haze?

«We show that the control of the droplet concentration (N), the environmental carrying - capacity (H0), and the cloud recovery parameter (τ) can be linked by a single nondimensional parameter (μ = √ N / (ατH0)-RRB-, suggesting that for deeper clouds the transition from open (oscillating) to closed (stable fixed point) cells will occur for higher droplet concentration (i.e., higher aerosol loading)...

The moisture is also robbed from the western US and migrated east by excessive aerosol spraying (too many condensation nuclei for the cloud droplets to combine and fall as rain).

Aerosol particles affect the Earth's radiative balance by directly scattering and absorbing solar radiation and, indirectly, through their activation into cloud droplets.

The formation of cloud droplets and cloud ice crystals is associated with suspended aerosols, which are produced by natural processes as well as human activities and are ubiquitous in Earth's atmosphere.

«In order to develop climate models, we have to consider microphysical processes, such as how a cloud droplet gets formed and how such droplets and physical conditions inside and outside of a cloud are changed by the presence of aerosols,» she said.

Greenhouse gases — like carbon dioxide — trap heat and warm the planet, while fine particles suspended in droplets, known collectively as aerosols, usually cool the planet by reflecting the sun's energy away.

a) decreases («dimming») until the 1980s, because atmospheric pollutants (aerosols) make the atmosphere more reflective and also clouds, by increasing the number of water droplets in the clouds, which in turn increases the amount of sunlight reflected, and subsequent

The underlying mechanism is that charged aerosols are more effective than neutral aerosols as ice nuclei (i.e., electrofreezing) and that the enhanced collections of charged evaporation nuclei by supercooled droplets enhance the production of ice by contact ice nucleation (i.e., electroscavenging).

But in vitro values become, in effect, theoretical calculations when they're applied by GCMs to model vastly greater columns of atmosphere, where cloud droplets and ice crystals, various aerosols and particulates — not to mention highly variable water vapor — appear in situ.

During this period, the aerosol amount varied with dust export from Africa, but also from major eruptions by two volcanoes (El Chichon in 1982 and Pinatubo in 1991), each of which left a reflective layer of sulfate droplets in the lower stratosphere for a couple of years.

The failure to actually reduce global emissions has meant that all possibilities are now on the table, including some that sound like premises from a science - fiction novel: Humans could sequester carbon dioxide by removing it from the air through technologies that mimic trees, or we could spray water droplets in the lower atmosphere to reflect light and heat back to space, or we could seed sulfur aerosols in the stratosphere to do the same.