Sentences with phrase «study effects of aerosols»

«Tiny particles have outsize impact on storm clouds, precipitation: Amazon rainforest provides a unique natural lab to study effects of aerosols.»

Not exact matches

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).

This unique orbit path will allow the CATS instrument to observe locations at different times of day and allow scientists to study day - to - night changes in cloud and aerosol effects from space.

The study also showed that the effect was much larger on a regional scale, counteracting possibly up to 30 % of warming in more rural, forested areas where anthropogenic emissions of aerosols were much lower in comparison to the natural aerosols.

During this event, the aerosols stayed close to the surface due to the presence of a anticyclone hovering over the study region at sea - level, «reducing the amount of shortwave irradiance reaching the surface and causing greater radiative cooling,» states Obregón, who likens the effects of desert dust with those resulting from certain forest fires or episodes of high pollution.

The cooling effect of aerosols can partly offset global warming on a short - term basis, but many are made of organic material that comes from sources that scientists don't fully understand, said Joost de Gouw, a research physicist at NOAA's Earth System Research Laboratory in Boulder, Colo., who is unaffiliated with the studies.

This mission is fulfilled by operating atmospheric observatories around the world that collect massive amounts of atmospheric measurements to provide data products that help scientists study the effects and interactions of clouds and aerosols and their impact on the earth's energy balance.

My main problem with that study is that the weather models don't use any forcings at all — no changes in ozone, CO2, volcanos, aerosols, solar etc. — and so while some of the effects of the forcings might be captured (since the weather models assimilate satellite data etc.), there is no reason to think that they get all of the signal — particularly for near surface effects (tropospheric ozone for instance).

One of the major parameters was the safety of these agents in the respiratory airways and lung parenchyma, since several of these agents are known to cause adverse effects.23 The main adverse effects observed were cough, transient fever and transient decrease in the respiratory functions after the aerosol administration.8, 19, 20 Moreover; it has been observed that excessive deposition of these agents in one site of the respiratory system can induce non-specific side effects in the form of pulmonary edema as observed with many other drugs.16 These side effects were milder when a premedication with bronchodilators and inhaled corticosteroids were administered.8, 19, 20 Until now no long term trial (> 9 months) has been performed since all patients included in previous studies had stage IV non-small cell lung cancer (NSCLC).

He has pioneered the use of SP - CAM to study aerosol - cloud interaction and used it together with satellite observations to constrain aerosol indirect effects.

Only a few estimates account for uncertainty in forcings other than from aerosols (e.g., Gregory et al., 2002a; Knutti et al., 2002, 2003); some other studies perform some sensitivity testing to assess the effect of forcing uncertainty not accounted for, for example, in natural forcing (e.g., Forest et al., 2006; see Table 9.1 for an overview).

Most studies consider a range of anthropogenic forcing factors, including greenhouse gases and sulphate aerosol forcing, sometimes directly including the indirect forcing effect, such as Knutti et al. (2002, 2003), and sometimes indirectly accounting for the indirect effect by using a wide range of direct forcing (e.g., Andronova and Schlesinger, 2001; Forest et al., 2002, 2006).

Some of these studies use the difference between Northern and Southern Hemisphere mean temperature to separate the greenhouse gas and aerosol forcing effects (e.g., Andronova and Schlesinger, 2001; Harvey and Kaufmann, 2002).

Plans and missions designed to study the effects of clouds and aerosols have been delayed or cancelled, Charlson and his colleagues write.

Scenes allude to the band's gloomy inclinations, bass - driven melodies and innovative use of audio effects (one band member uses an aerosol spray can to form a beat), but the story of Joy Division is an afterthought in the movie, replaced instead by a much more routine study of depression and the effects of sudden success and touring on a marriage.

If industry - generated aerosols have a more limited cooling effect than originally thought, we can clean up and scale down dirty coal plants without worrying too much about consequent sudden jumps in global temperatures of up to 2 degrees C (if I remember the upper limits of earlier studies correctly).

Similarly, a Bayesian study of hemispheric mean temperatures from 1900 to 1996 finds decisive evidence for an aerosol cooling effect (Smith et al., 2003).

CLOUD is designed to study the effects of cosmic rays on aerosols, cloud droplets and ice particles, under precisely controlled laboratory conditions.

This was shown to be the case for near - surface temperatures in the PCM (Meehl et al., 2004), in the Hadley Centre Climate Model version 2 (HadCM2; Gillett et al., 2004c) and in the GFDL CM2.1 (see Table 8.1) model (Knutson et al., 2006), although none of these studies considered the indirect effects of sulphate aerosols.

So, I knew I'd find papers discussing experimental studies of the effect of aerosols at meetings that Jim attended!

The study focuses on one proposed type of SRM, known as a «stratospheric aerosol injection», which involves sending up substances to the stratosphere that are known to have a cooling effect on the climate.

«It perhaps suggests that the role of sulphate aerosols, that cooling effect, was less powerful than we thought,» said Mike Hulme from the University of East Anglia (UEA), who was not involved in the study.

R&S 71 was one of the first studies using modeling, and their results found minimal warming effects from CO2 and large cooling effects from aerosols.

In our study, the biggest aerosol effect on climate came from the effect of aerosol - cloud indirect effect.

An analysis of the very recent studies of stratospheric aerosol changes following a giant solar energetic particles event shows a similar negligible effect.

This study found that black carbon has a warming effect of approximately 0.9 W / m2, while aerosol cooling effects account for approximately -2.3 W / m2.

However, this study focused on the warming effects of black carbon, and did not compare them to the cooling effects of atmospheric aerosols.

Fan went to China in 2008 for an ARM Mobile Facility field campaign studying the climatic effects of aerosols in that country's fast - changing atmosphere.

However, the GWPF report only references the «main results» of Aldrin et al. (2012), whose study actually estimated equilibrium climate sensitivity of about 2.5 or 3.3 °C when accounting for cloud and indirect aerosol effects.

The study researches the effects of microbial control on sea spray aerosol, along with the blooms included within, in an isolated facility that simulates the atmosphere of the ocean with 3,400 gallons of seawater.

Aerosol collections on the NOAA Ron Brown for subsequent processing of INP activation temperature spectra and composition analyses, add a valuable measurement to the ACAPEX and related CalWater2 (NOAA) studies for use in parameterizing and modeling the impacts of marine boundary layer and other aerosols on climate and radiation via aerosol - indirect effects on mixed phase Aerosol collections on the NOAA Ron Brown for subsequent processing of INP activation temperature spectra and composition analyses, add a valuable measurement to the ACAPEX and related CalWater2 (NOAA) studies for use in parameterizing and modeling the impacts of marine boundary layer and other aerosols on climate and radiation via aerosol - indirect effects on mixed phase aerosol - indirect effects on mixed phase clouds.

Several studies have considered the response of a GCM with a mixed - layer ocean to indirect aerosol effects (Rotstayn et al., 2000; K. Williams et al., 2001; Rotstayn and Lohmann, 2002) or to a combination of direct and indirect aerosol effects (Feichter et al., 2004; Kristjansson et al., 2005; Takemura et al., 2005).

Microphysical theories regarding CR - cloud links via ion - mediated nucleation are well developed, and several studies have attempted to incorporate these effects within atmospheric models to estimate the magnitude of potential affects to aerosols and clouds.

Cloud - resolving models of cumulus and stratocumulus case studies also diagnose semi-direct effects indicating a similar relationship between the height of the aerosol layer relative to the cloud and the sign of the semi-direct effect (Ackerman et al., 2000; Ramanathan et al., 2001; Johnson et al., 2004; Johnson, 2005).

In fact, most of the GCM studies of the indirect aerosol effect used sulphate as a surrogate for the total anthropogenic fraction of the aerosol (e.g., Boucher and Lohmann, 1995; Feichter et al., 1997; Lohmann and Feichter, 1997).

A large number of modeling studies have been carried out to characterize the spatial variability in aerosol forcing due to direct, indirect, and semidirect effects (IPCC, 2001).

This mission is fulfilled by operating atmospheric observatories around the world that collect massive amounts of atmospheric measurements to provide data products that help scientists study the effects and interactions of clouds and aerosols and their impact on the earth's energy balance.

A modeling study of the direct effect of aerosol over the Tropical Indian Ocean.

2) The effects of clouds and aerosols on radiative heat transfer, which are many and varied and still being studied with many questions open.

Stratospheric ozone science: To elucidate the geographical extent of, and mechanisms responsible for, ozone depletion in the «ozone hole» region and to study dilution effects and possible heterogeneous chemistry even outside of the polar regions due to sulphate aerosols.

I also predict it will be accompanied by studies showing either: a) The quantity of atmospheric aerosol from the 40's -70's is much less than previously thought b) The cooling effect of aerosols is much less significant than previously thought

While multiple studies have shown the Northern Hemisphere plays a stronger role than the Southern Hemisphere in transient climate change, this had not been included in calculations of the effect of atmospheric aerosols on climate sensitivity.

This study will examine the current state of knowledge regarding the direct and indirect radiative forcing effects of gases, aerosols, land use, and solar variability on the climate of the Earth's surface and atmosphere and it will identify research needed to improve our understanding of these effects.

Although previous research had seemed to indicate that aerosols could create a general cooling effect in the atmosphere — thus helping mitigate the effect of global warming — a new study has revealed that they may in fact warm it just as much as greenhouse gases.

The new study, published in Nature Geoscience, identified a negative feedback loop in which higher temperatures lead to an increase in concentrations of natural aerosols that have a cooling effect on the atmosphere.

The study also showed that the effect was much larger on a regional scale, counteracting possibly up to 30 % of warming in more rural, forested areas where anthropogenic emissions of aerosols were much lower in comparison to the natural aerosols.

Topics that I work on or plan to work in the future include studies of: + missing aerosol species and sources, such as the primary oceanic aerosols and their importance on the remote marine atmosphere, the in - cloud and aerosol water aqueous formation of organic aerosols that can lead to brown carbon formation, the primary terrestrial biological particles, and the organic nitrogen + missing aerosol parameterizations, such as the effect of aerosol mixing on cloud condensation nuclei and aerosol absorption, the semi-volatility of primary organic aerosols, the importance of in - canopy processes on natural terrestrial aerosol and aerosol precursor sources, and the mineral dust iron solubility and bioavailability + the change of aerosol burden and its spatiotemporal distribution, especially with regard to its role and importance on gas - phase chemistry via photolysis rates changes and heterogeneous reactions in the atmosphere, as well as their effect on key gas - phase species like ozone + the physical and optical properties of aerosols, which affect aerosol transport, lifetime, and light scattering and absorption, with the latter being very sensitive to the vertical distribution of absorbing aerosols + aerosol - cloud interactions, which include cloud activation, the aerosol indirect effect and the impact of clouds on aerosol removal + changes on climate and feedbacks related with all these topics In order to understand the climate system as a whole, improve the aerosol representation in the GISS ModelE2 and contribute to future IPCC climate change assessments and CMIP activities, I am also interested in understanding the importance of natural and anthropogenic aerosol changes in the atmosphere on the terrestrial biosphere, the ocean and climate.

Several observational studies (see Chapter 5) support the existence of the first aerosol indirect effect on low - level clouds and a negative sign for the associated radiative forcing, but these studies do not give indications on what a (negative) upper bound of the forcing would be.

Plans and missions designed to study the effects of clouds and aerosols have been delayed or cancelled, Charlson and his colleagues write.