Sentences with phrase «of atmospheric dust»

Other sources of lag could be the time required for the ocean to mix vertically, for sea - ice to melt, for oceanic biological productivity to change, and / or for the concentrations of atmospheric dust to change («Timing of Atmospheric CO2 and Antarctic Temperature Changes Across Termination III», Science Magazine # 299).

To test the effect of atmospheric dust, we ran the GISS climate model with observed SSTs for 1932 - 1939, with and without the presence of a dust source over the Great Plains.

Claquin et al's model - derived findings show a change in tropical atmospheric forcing of «-- 2.2 to — 3.2 W m — 2» between PI and LGM earth, due to the increased albedo of atmospheric dust.

According to the study's authors, quantifying the amount and sources of atmospheric dust concentrations is also important to improve future climate change predictions.

Results: Tiny bits of atmospheric dust and particles called aerosols may play a big role in global climate change, but just how big a role is not well understood.

Combining the two instruments» data will help isolate the confounding effects of atmospheric dust.

Not exact matches

They found similar proportions of lead in atmospheric mineral dust samples collected in Switzerland.

Possible causes of IAD include recurrent pulmonary stress, deep inhalation of dust, atmospheric pollutants and persistent respiratory viral infections.

Even as the importance of biological ice nucleation was being recognized by agricultural scientists, it still wasn't embraced by atmospheric scientists, who stuck by the traditional view that soot, or sea salt, or some as - yet - unidentified mineral in dust was seeding ice in clouds.

By the 1990s, the Owens Lake playa was the largest producer in North America of PM10 atmospheric dust — particulate matter small enough to enter human lungs.

But Zahnle, an expert on atmospheric escape of gases, agrees with the main thrust of the study: Right now, dust storms are helping to bleed Mars dry.

Yoav Yair of the Open University in Ra'anana, Israel, and colleagues spent more than a year analysing the video, which was originally taken to study atmospheric dust.

Schneider coauthored a 1971 article in the journal Science about atmospheric aerosols — floating particles of soil dust, volcanic ash, and human - made pollutants.

But although some evidence points to past water oceans on Mars, only small amounts of carbonates have been found there — in Martian meteorites that landed on Earth and in atmospheric dust and bright soils on the planet.

To investigate the layers and composition of clouds and tiny airborne particles like dust, smoke and other atmospheric aerosols,, scientists at NASA's Goddard Space Flight Center in Greenbelt, Maryland have developed an instrument called the Cloud - Aerosol Transport System, or CATS.

Dust, ozone, and carbon can accumulate in valleys and basins, and mercury can be pulled to earth through atmospheric sinks that deposit it across large swaths of land.

It can attach to dust particles and rain out of the sky, in a process called atmospheric deposition.

The lead surrounding the stars — which was part of the original cloud of gas and dust from which these stars formed, not generated by reactions in the evolving stars themselves — may be dispersed within an atmospheric layer as much as 100 kilometers thick (depicted patchily in pink) that altogether weighs up to 100 billion metric tons.

Roughly half the mercury contamination in the United States comes from Asia; much of it may arrive aboard particles in atmospheric dust clouds.

For example, Mars experiences global dust storms in addition to its annual cycles of atmospheric freeze - out at the poles.

Prospero, J.M. et al. (2002): Environmental characterization of global sources of atmospheric soil dust identified with the nimbus 7 total ozone mapping spectrometer (TOMS) absorbing aerosol product, Rev. Geophys.

This method tries to maximize using pure observations to find the temperature change and the forcing (you might need a model to constrain some of the forcings, but there's a lot of uncertainty about how the surface and atmospheric albedo changed during glacial times... a lot of studies only look at dust and not other aerosols, there is a lot of uncertainty about vegetation change, etc).

Ice sheet albedo forcing is estimated to have caused a global mean forcing of about — 3.2 W m — 2 (based on a range of several LGM simulations) and radiative forcing from increased atmospheric aerosols (primarily dust and vegetation) is estimated to have been about — 1 W m — 2 each.

2) Most actual atmospheric cloud droplets form around dust particles including bacteria, rather than starting from minute droplets of pure water.

This was a relatively stable climate (for several thousand years, 20,000 years ago), and a period where we have reasonable estimates of the radiative forcing (albedo changes from ice sheets and vegetation changes, greenhouse gas concentrations (derived from ice cores) and an increase in the atmospheric dust load) and temperature changes.

Large scale dust storms change the atmospheric opacity and convection; as always when comparing mean temperatures, the altitude at which the measurement is made matters, but to the extent it is sensible to speak of a mean temperature for Mars, the evidence is for significant cooling from the 1970's, when Viking made measurements, compared to current temperatures.

CO2's effect of stimulating plant growth and increasing plant tolerance of aridity contributed to revegetating large areas of land that were desert at the LGM, compounding the effects of an increase in atmospheric humidity, reduced land / ocean surface ocean ration, and increased warmth, all of which combined caused the reduction of airborne dust and atmosperic albedo.

Other forcings, including the growth and decay of massive Northern Hemisphere continental ice sheets, changes in atmospheric dust, and changes in the ocean circulation, are not likely to have the same kind of effect in a future warming scenario as they did at glacial times.

The system has a large number of interacting parts — cloud, ice, biology, dust, ocean and atmospheric circulation — that together result in climate variation at all scales.

Since coming to PNNL, he has led or been significantly involved in studies of effects of surface heterogeneity on boundary layer structure, of mesoscale atmospheric flows induced or modulated by complex terrain, of the simulation of dust emission by wind erosion, and of the capabilities of a variety of atmospheric instruments — including a mass spectrometer and wind profiling radar — for measuring atmospheric turbulence.

The Sun, Jupiter, gravitational moment of the remaining planets, Earth angular orbit variations of all kinds, galactic rays, motion of the solar system through the galaxy and dust clouds, the Moon, atmospheric water vapor, ocean currents, configuration of the tectonic plates and continental drift, volcanic activity, the natural biosphere, human urban development, human alteration of the greenhouse water cycle (dam's, rivers etc),,... human produced CO2.

Think on atmospheric chemistry, individual rates for the reactions of nitrogen oxides and oxy - radicals can dependent on concentration, atmospheric pressure, temperature, light flux, liquid water levels, silicate surface (from dust) and «unknown unknowns *».

The variability is due to day - to - day variations in temperature, strength of the surface - based temperature inversion, atmospheric humidity, and the presence of «diamond dust» (near - surface ice crystals).

«The beginning of the Bølling - Alleröd warm period was marked in Greenland by an abrupt rise in 18O, an abrupt drop in dust rain, and an abrupt increase in atmospheric methane content.

There are a number of man - made contributory factors that may have had specific impacts on the atmospheric heating, e.g. local warming in the cities (due to housing, roads, and other resultant factors), smoke and dust over long distances or deforestation of huge forest areas.

The second part of the dissertation analyzes dust emission in an atmospheric general circulation model (AGCM), where realistic simulation is inhibited by the model's coarse resolution compared to the scale of the circulations observed to mobilize dust.

Effects of the volcanic dust and all other atmospheric material are a major unresolved problem.

Hubert Lamb, founder of the CRU, identified a major part of the aerosol problem in 1970 when he created the Dust Veil Index (DVI) designed to quantify the impact of volcanic dust on the atmospheric energy balaDust Veil Index (DVI) designed to quantify the impact of volcanic dust on the atmospheric energy baladust on the atmospheric energy balance.

They showed the evidence to 77 domain experts (i.e., atmospheric chemists with expertise in condensation trails, and geochemists working on atmospheric deposition of dust and pollution), and asked about each of the claims made by «SLAP theorists.»

Most of the GMT drop has been attributed to radiative forcing decreases from increased albedo due to equatorward ice extension and from decreased greenhouse gas concentrations; vegetation and atmospheric dust are thought to play secondary roles (20, 21).

The positive atmospheric forcing is due largely to the soot and dust absorption of solar radiation.

As shown by our simulations with a climate − carbon cycle model, such a relationship between dust and climate implies that dust - induced cooling is responsible for the final step from intermediate to extreme glacial cooling and drawdown of atmospheric CO2 concentrations.

The increased atmospheric dust load during glacial times is thought to be due to a generally colder and drier atmosphere, which increased the number and strength of dust sources through reduced vegetation cover (28), and reduced washout of suspended particles during transport (7).

We know there are effects from land use change and we know we have added to atmospheric backscatter of solar radiation from particulates (sulfate aerosols, dust from agriculture...) but we are no longer certain of the net sign of anthropogenic temperature change.

The accuracy of the simulations of GST by IPCC would also be improved significantly by introducing the influence of fine dust from the actual atmospheric nuclear explosions into their climate models; thus, global warming behavior could be more accurately predicted

Note that solar energy loss calculations through the air mass do NOT account for reflections off of either high clouds or low clouds or atmospheric dust and turbidity: they are based on «clear sky» conditions regardless of clouds, dust, storms or wind.

It is further argued that the transition of vertical circulation patterns is in response to adjustments to geostrophic imbalance — an adjustment time scale of 6 — 9 h. Although unproven, we suggest that antecedent rainfall over the alkali desert 2 weeks prior to the event was instrumental in lowering the bulk density of sediments and thereby improved the chances for dust ablation by the atmospheric disturbance.

Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450 — 600 ppmv over the coming century are irreversible dry - season rainfall reductions in several regions comparable to those of the «dust bowl» era and inexorable sea level rise.

The Barbados annual dust cycle is linked to the cycle of dust activity in North Africa and to seasonal changes in large - scale atmospheric circulation patterns.

The researchers, most of them based at Columbia University's Lamont - Doherty Earth Observatory, say it cements the theory that atmospheric moisture, and thus dust, move in close step with temperature on a global scale; the finding may in turn help inform current ideas to seed oceans with iron - rich dust in order to mitigate global warming.