Sentences with phrase «with aerosol particles»

The problem with clouds in climate models are of two different types: the first is a microphysics / chemistry one, regarding the physics and chemistry of how a population of cloud particles interacts with aerosol particles and evolves with time.

One of the key uncertainties is clouds, understanding the physics behind clouds and how clouds interact with aerosol particles.

Shiraiwa, M., Sosedova, Y., Rouvière, A., Yang, H, Zhang, Y., Abbatt, J. P. D., Ammann, M., and Pöschl, U.: The role of longlived reactive oxygen intermediates in the reaction of ozone with aerosol particles, Nature Chemistry, 3, 291 - 295, 2011.

In particular, they propose that cloud changes associated with aerosol particles in the atmosphere could be causing the weekend effect, though other pollution processes can not be ruled out at this time.

Not exact matches

After allowing for humidity and rainfall, they found that «aerosol optical thickness» — a measure of the concentration of atmospheric particles — decreased by only 10 to 15 per cent compared with the same periods in 2002 to 2007 (Geophysical Research Letters, in press).

During storms, they flew a research aircraft with several powerful instruments, including one that can identify the type of particle in a cloud and determine whether it was dust or some other type of aerosol.

With PNNL's climate model, Smith created more than 1,400 potential scenarios to reflect the many possibilities surrounding aerosols, tiny particles including soot that float in the atmosphere.

It then combines with pollutants from combustion — mainly nitrogen oxides and sulfates from vehicles, power plants and industrial processes — to create tiny solid particles, or aerosols, no more than 2.5 micrometers across, about 1/30 the width of a human hair.

And the way those droplets form - with scarce or plentiful aerosol particles - could have serious implications for weather and climate change.

Black carbon aerosols — particles of carbon that rise into the atmosphere when biomass, agricultural waste, and fossil fuels are burned in an incomplete way — are important for understanding climate change, as they absorb sunlight, leading to higher atmospheric temperatures, and can also coat Arctic snow with a darker layer, reducing its reflectivity and leading to increased melting.

Until recently, the U.S. Department of Homeland Security has been investigating whether seeding storm clouds with pollution - size aerosols (particles suspended in gas) might help slow tropical cyclones.

Albedo modification would work by lacing the atmosphere with tiny particles or aerosols that would reflect sunlight and mimic natural processes.

Ginot and his team of researchers can also track aerosols — small particles in the atmosphere that fall with snow and get trapped and stored in the ice, layer by layer, as the years pass.

Preliminary analyses show that most of the pollution was sulphate aerosols — along with dust and carbonaceous particles such as black carbon.

Aerosol pollution also affects the formation of clouds, which are seeded with dust particles in the atmosphere.

Previous studies with primates suggest that aerosols of most biothreat agents, which are particles dispersed in the air, are infectious.

Mikhailov, E., Vlasenko, S., Martin, S.T., Koop, T., and Pöschl, U.: Amorphous and crystalline aerosol particles interacting with water vapour: conceptual framework and experimental evidence for restructuring, phase transitions and kinetic limitations, Atmospheric Chemistry and Physics, 9, 9491 - 9522, 2009.

There are several variations on the so - called solar geoengineering theme, but they all have the same end - goal: using aerosols to blanket our atmosphere with reflective particles in order to quickly lower global temperatures.

Additionally, stimulated bacterial degradation might heavily affect the organic composition of nascent sea - spray particles, upon which relies the ability of marine aerosols to interact with the climate system.

Getting the data used in these 30 - plus papers, with more to come, required extensive coincident measurements of meteorology, sunlight comings and goings, trace gases, and aerosol particles.

This research is the first to connect a commercial CCN, with a CVI and mass spectrometers to study the chemistry of aerosol particles that activate to cloud droplets.

In general, the risk of aerosol transmission increases with proximity and duration of exposure to the source; however, once aerosolized, certain pathogens may remain infective over long distances, depending on particle size, the nature of the pathogen, and such environmental factors as temperature and humidity.3

Maybe one could add instead: «This downward radiation from greenhouse gases (and some fine solid air particles («aerosols») e.g. can be measured at the surface in nights with clear sky and no other radiation sources in the atmosphere (e.g. Philipona and Dürr 2004 doi / 10.1029 / 2004GL020937).

A paper discussing the difficulty of getting from nm sized nucleation mode to a size that can generate cloud particles is: Erupe, M. E., et al. (2010), Correlation of aerosol nucleation rate with sulfuric acid and ammonia in Kent, Ohio: An atmospheric observation, J. Geophys.

We also know quite accurately the spectral absorption characteristics for the absorbing gases, and how cloud and aerosol particles interact with thermal radiation.

It is shown that such photopolarimetric data are highly sensitive to the size distribution and refractive index of aerosol particles, which reduces the nonuniqueness in aerosol retrievals using such data as compared with less comprehensive datasets.

I write it off as a very real effect that is not well characterized by the models, probably because these models don't model with enough accuracy the effect of the additional aerosol particles on cloud production to properly account for it's full effect on temperature.

The parameterization of the interactions are at all levels; from estimation of the geometric characterization of the aerosols, to the numbers of particles, to connections with several important aspects of clouds, and finally to the interactions with radiative energy transport.

Ambient submicron particle measurements were made with a high - resolution time - of - flight aerosol mass spectrometer (AMS) at the north campus of the University of California Irvine, which is located in the SoCAB approximately 5 miles inland from the Pacific Ocean.

The remainder is made up with the other minor greenhouse gases, ozone and methane for instance, and a small amount from particles in the air (dust and other «aerosols»).

It then combines with pollutants from combustion — mainly nitrogen oxides and sulfates from vehicles, power plants and industrial processes — to create tiny solid particles, or aerosols, no more than 2.5 micrometers across, about 1/30 the width of a human hair.

Coupling these new measurements with detailed cloud simulations that resolve the size distributions of aerosols and cloud particles, we found several lines of evidence indicating that most anvil crystals form on mid-tropospheric rather than boundary - layer aerosols.

It is found that with a number concentration of aerosol particles of ∼ 102 — 103 cm − 3 (which corresponds to the aerosol density in the deposited layer of about 1 — 10 mg / m2 with the layer thickness along the ray path of about 100 m) the solar radiation attenuation with artificial aerosol layers accounts for 1 to 10 %.

Associated with human greenhouse gas production is the release of fine particle known as aerosols which have a temporary cooling effect (they last in the atmosphere less than a week).

This method uses consistency between direct normal and diffuse horizontal measurements together with a special regression technique for retrieval of daily time series of column mean aerosol particle size, aerosol optical depth, NO2, ozone and water vapor column amounts together with the instrument's calibration constants.

The position statement opens with the following: «Careful and comprehensive scientific assessments have clearly demonstrated that the Earth's climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing aerosol particles (IPCC, 2007).

The cloud condensation nuclei counter measures the concentration of aerosol particles by drawing an air sample through a column with thermodynamically unstable supersaturated water vapor that can condense onto aerosol particles.

Aerosols A suspension of airborne solid or liquid particles, with a typical size between a few nanometres and 10 μm that reside in the atmosphere for at least several hours.

This system measures aerosol optical properties to better understand how particles interact with solar radiation and influence the Earth's radiation balance.

While these particles soon fall back down to Earth and allow the planet to heat up again, the thinking with so - called solar geoengineering is that this thin layer of reflective sulfate aerosols would be replenished to help keep it cool.

With regard to the actual content of the press release quoted, it isn't clear if the process they report on (aerosol particles, particularly organic chemicals, getting smaller over time) makes them better or worse at forming clouds and their other atmosphere cooling functions.

Cloud condensation nuclei: Aerosol particles that provide a platform for the condensation of water vapor, resulting in clouds with higher droplet concentrations and increased albedo.

Here, gasses react with water to form aerosol particles that linger in the stratosphere for one or two years, reflecting sunlight and heat from the sun, and cooling the planet.

However, there have been proposals to mitigate climate change not by decreasing greenhouse gas emissions, but by increasing the reflection of incoming solar radiation with mirrors, aerosols (small particles), or other means.

It has been hypothesized that galactic cosmic rays (GCR) create atmospheric ions which facilitates aerosol nucleation and new particle formation with a further impact on the cloud formation (Kazil et al., 2012; Pierce and Adams, 2009).

The AOS measures aerosol optical properties to better understand how particles interact with solar radiation and influence the earth's radiation balance.

Aerosols - A collection of airborne solid or liquid particles, with a typical size between 0.01 and 10 micrometer (~ 0.00000039 and ~ 0.00039 inch) that reside in the atmosphere for at least several hours.

«Earth system models» include all that and much more: forests that can shrink or spread as conditions change; marine food webs that react as the oceans grow more acidic with carbon dioxide; and aerosol particles in the atmosphere that interact with greenhouse gases, enhancing or sapping their warming power.

Recently it was suggested that the formation of new atmospheric aerosol particles is connected with the existence of thermodynamically stable 1 - to 2 - nm clusters, formed in the atmosphere by some nucleation mechanism.

Interactions with the hydrological cycle, and additional impacts on the radiation budget, occur through the role of aerosols in cloud microphysical processes, as aerosol particles act as cloud condensation nuclei (CCN) and ice nuclei (IN).