Sentences with phrase «for atmospheric aerosol»

«galactic cosmic rays appear to play a minor role for atmospheric aerosol formation events, and so for the connected aerosol - climate effects as well.»

For atmospheric aerosol, this shape factor is usually not strongly different from one; its effect is usually assumed negligible compared to the effect of particle size, which covers several orders of magnitude.

Our main conclusion is that galactic cosmic rays appear to play a minor role for atmospheric aerosol formation events, and so for the connected aerosol - climate effects as well.

At present, only one regional boundary (south Asian monsoon) can be established for atmospheric aerosol loading.

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).

«Volcanic aerosols in the stratosphere absorb infrared radiation, thereby heating up the stratosphere, and changing the wind conditions subsequently,» said Dr. Matthew Toohey, atmospheric scientist at GEOMAR Helmholtz Centre for Ocean Research Kiel.

For example, the tiny particles known as aerosols are far better understood, says atmospheric scientist Piers Forster of the University of Leeds in England andalso a lead author.

Mission leaders were relieved and eager to begin their studies of cloud and haze effects, which «constitute the largest uncertainties in our models of future climate — that's no exaggeration,» says Jens Redemann, an atmospheric scientist at NASA's Ames Research Center in Mountain View, California, and the principal investigator for ObseRvations of Aerosols above CLouds and their IntEractionS (ORACLES).

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.

Plants release gases that, after atmospheric oxidation, tend to stick to aerosol particles, growing them into the larger - sized particles that reflect sunlight and also serve as the basis for cloud droplets.

Yet there is no doubt that research into atmospheric aerosols is becoming increasingly important due to the effects that they can have on the global temperature of Earth, given that solar radiation is the main source of energy for Earth - Atmosphere system.

«Scientists have talked about Arctic melting and albedo decrease for nearly 50 years,» said Ramanathan, a distinguished professor of climate and atmospheric sciences at Scripps who has previously conducted similar research on the global dimming effects of aerosols.

Mims's research and writings span topics ranging from atmospheric aerosols to home electronics; he is probably best known for the educational electronics kits and books he has created for RadioShack, which have introduced generations of young experimenters to electronics.

Atmospheric aerosols play important roles in climate and atmospheric chemistry: They scatter sunlight, provide condensation nuclei for cloud droplets, and participate in heterogeneous chemical reactions.

Processes for which global - level boundaries can not yet be quantified are represented by gray wedges; these are atmospheric aerosol loading, novel entities, and the functional role of biosphere integrity.

In the journal «Angewandte Chemie,» Jokinen and co-workers report that auto - oxidation, which can, for example spoil plastics or food, also plays an important role in the atmospheric aerosol formation.

«The backward - enhanced plasma emission spectrum from water droplets or biological agents,» they write, «could be attractive for remotely determining the composition of atmospheric aerosol.»

The ARM Facility has provided the world's atmospheric scientists with continuous observations of cloud and aerosol properties and their impacts on the Earth's energy balance for more than 20 years.

Sally, who was nominated by Dr. Beat Schmid, Associate Director, Atmospheric Sciences and Global Change Division, was honored for her exceptional contribution in the field of atmospheric science, particularly in her efforts to improve understanding of the radiative effect of clouds and aerosols on the Earth's atmosphere and their representation in climate models.

These oligomers are also the starting materials for troubling atmospheric aerosols, known as secondary organic aerosols.

Development of new instruments and methods for measurement of properties of atmospheric aerosols and cloud - aerosol properties

Methods: In this new approach, the team began with an atmospheric aerosol sample that contains thousands of molecules formed in the reactions of ozone, a common atmospheric oxidant, with limonene, a molecule emitted by various types of trees, which is responsible for the citrus scent found walking among the orange trees.

The AMT, for example, is designed to evaluate the performance of aerosol process modules that calculate specific climate - relevant atmospheric processes.

Analyzing such systems, whether they are on the surface of a catalyst, a microbial community, or atmospheric aerosols, and understanding their impact requires tools that can accurately identify and quantify hundreds of molecules,» said Dr. Julia Laskin, a PNNL chemist, who has been advancing the frontiers of the Nanospray Desorption Electrospray Ionization Mass Spectrometry, nicknamed nano - DESI, for the last 3 years.

The top priorities should be reducing uncertainties in climate sensitivity, getting a better understanding of the effect of climate change on atmospheric circulation (critical for understanding of regional climate change, changes in extremes) and reducing uncertainties in radiative forcing — particularly those associated with aerosols.

With her colleagues from around the world, she is designing techniques to better characterize complex molecules in biological samples, atmospheric aerosols, and biofuels, work critical for a secure energy future.

The ARM Aerosol Measurement Science Group (AMSG) coordinates ARM Climate Research Facility observations of aerosols and atmospheric trace gases with user needs to ensure advanced, well - characterized observational measurements and data products — at the spatial and temporal scales necessary — for improving climate science and model forecasts.

The measured energy imbalance accounts for all natural and human - made climate forcings, including changes of atmospheric aerosols and Earth's surface albedo.

The paper describes and evaluates CAM5, the advanced aerosol module for the Community Earth System Model, which provides a clearer picture of these atmospheric particles.

In the unlikely case of an abrupt fuel burning cessation, we could add aerosols at a decreasing rate, both to smooth the transition, but also because atmospheric CO2 would drop significantly during the first few years after a cessation, as the shorter term reservoirs have not yet come to equilibrium and would still be absorbing CO2 at a decent clip for several years.

For the first time, simultaneous global observations of the ERB and a multitude of cloud, aerosol, and surface properties and atmospheric state data are available with a high degree of precision.»

However, calculation of the radiative forcing is again a job for the line - by - line codes that take into account atmospheric profiles of temperature, water vapour and aerosols.

The important point here is that a small external forcing (orbital for ice - ages, or GHG plus aerosols & land use changes in the modern context) can be strongly amplified by the positive feedback mechanism (the strongest and quickest is atmospheric water vapor - a strong GHG, and has already been observed to increase.

However, under a climate mitigation scenario for the twenty - first century in which sulphate aerosols decline before atmospheric CO2 is stabilized, this «diffuse - radiation» fertilization effect declines rapidly to near zero by the end of the twenty - first century.»

We have performed such experiments for the principal greenhouse gases, clouds, and aerosols using the [Goddard Institute] climate model by systematically inserting, or taking out, each atmospheric constituent one at a time, and recording the corresponding radiative flux change.

Pollutant gas and aerosol emissions levels in the reference scenario were checked for consistency by estimating regional surface particulate and ozone levels using the MOZART atmospheric chemistry model.

On the other hand I am co-plotting, down to sub-annual timescales up to 3 or even perhaps 4 well defined physical parameters relating to both the sea surface (e.g. SST, chlorophyll a, surface leaving radiance), the immediate subsurface (e.g. diffuse attenuation of 490 nm light to approx 50 m depth) and atmospheric aerosol size e.g. AOT at 865 and 890 nm — all measured with modern, state of the art surface telemetry and remote sensing methods and simply looking for mechanistic links between these parameters on sub-annual timescales.

Differences in future atmospheric burdens and radiative forcing for aerosols are dominated by divergent assumptions about emissions from South and East Asia.

An international team of researchers report in Nature Communications that they made a computer model of the planet's atmospheric conditions: they included natural and human - triggered aerosols, volatile organic compounds, greenhouse gases and other factors that influence temperature, one of which is albedo: the scientist's word for the capacity of terrain to absorb or reflect solar radiation.

Basic physical science considerations, exploratory climate modeling, and the impacts of volcanic aerosols on climate all suggest that SWCE could partially compensate for some effects — particularly net global warming — of increased atmospheric CO2.

Climate models are like weather models for the atmosphere and land, except they have to additionally predict the ocean currents, sea - ice changes, include seasonal vegetation effects, possibly even predict vegetation changes, include aerosols and possibly atmospheric chemistry, so they are not like weather models after all, except for the atmospheric dynamics, land surface, and cloud / precipitation component.

Some of the more complex models now account explicitly for the dynamics of the aerosol size distribution throughout the aerosol atmospheric lifetime and also parametrize the internal / external mixing of the various aerosol components in a more physically realistic way than in the TAR (e.g., Adams and Seinfeld, 2002; Easter et al., 2004; Stier et al., 2005).

Such mixtures of absorbing and scattering aerosols (including other particulate matter such as nitrate, potassium and so on) are referred to as ABCs, for atmospheric brown clouds11» https://www.nature.com/articles/ngeo918

As the Director of GISS and Principal Investigator for the GISS ModelE Earth System Model, I am interested in understanding past, present and future climate and the impacts of multiple drivers of climate change, including solar irradiance, atmospheric chemistry, aerosols, and greenhouse gases.

This capability is also important for atmospheric chemistry and aerosol studies where the emission sources are localized and non-uniformly distributed.

Research shows the Clean Air Act was likely responsible for a dramatic decline in atmospheric organic aerosol.

Anomalies in the volcanic - aerosol induced global radiative heating distribution can force significant changes in atmospheric circulation, for example, perturbing the equator - to - pole heating gradient (Stenchikov et al., 2002; Ramaswamy et al., 2006a; see Section 9.2) and forcing a positive phase of the Arctic Oscillation that in turn causes a counterintuitive boreal winter warming at middle and high latitudes over Eurasia and North America (Perlwitz and Graf, 2001; Stenchikov et al., 2002, 2004, 2006; Shindell et al., 2003b, 2004; Perlwitz and Harnik, 2003; Rind et al., 2005; Miller et al., 2006).

The parameterization is intended for application in large - scale atmospheric and cloud models that can predict 1) the supersaturation of water vapor, which requires a representation of vertical velocity on the cloud scale, and 2) concentrations of a variety of insoluble aerosol species.

Consequently, the most advanced climate models now require, in addition to concentrations or emissions of greenhouse gases (CO2, CH4, N2O and halocarbons), emissions of reactive gases and aerosol precursor compounds (SO2, NOx, VOC, BC, OC and NH3), to model atmospheric chemistry and interactions with the climate system.6 For most variables, a sectoral differentiation would improve the quality of the calculations (e.g. from power plants and agricultural burning).

Overall forcing at the TOA is negative averaged over all aerosols, but significant atmospheric heating and a net positive TOA forcing is possible for aerosols with a strong black carbon component, and some of this will eventually be transmitted to the surface despite the reduction in surface insolation from the light scattering and absorptive properties of the aerosols.