It seems ‘classical dust cycle models have over-estimated the amount of dust emission.’ This in turn affects the results from climate models, which ‘have only been providing a fraction of the story’. This ‘has significant implications’ for reconstructions of past climate.
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You may think of dust as an annoyance to be vacuumed and disposed of, but actually, on a grander scale, it is far more important than most people realize, says Phys.org.
Globally, dust plays a critical role in regulating our climate, radiation balance, nutrient cycles, soil formation, air quality and even human health.
But our understanding of it has been hampered by limitations in current mathematical models. These models, built on methods developed decades ago, struggle to accurately simulate the properties and quantities of dust.
The latest research by my colleagues and I sheds light on these limitations and suggests a more nuanced picture of dust. Our findings reveal that dust emissions are not constant but shift seasonally and between hemispheres, across deserts and shrublands.
This challenges the long-held notion that north Africa and the Middle East are the dominant sources of global dust.
Using two types of satellite data, our research suggests that dust emissions during dust storms are rare and localized, much like lightning strikes, and occur in constantly shifting locations.
. . .
[The article concludes…]
These new findings are crucial for large scale models because the properties of dust are different depending on where they come from. Not only that, but dust may change as it is transported within a hemisphere to different destinations where it settles on land, in our oceans and on icecaps.
Our new understanding of dust distribution, quantity and seasonal shifts has significant implications. It will require revisions to historical reconstructions that explain past climate changes.
Our findings will also influence future climate projections and how the dust cycle interacts with the carbon, energy and water cycles of Earth’s systems.
Full article here.
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Image: Saharan dust storm [credit: BBC]
Tallbloke's Talkshop 
Really? Talk about grant hunting. The dust has been around for a few million years, gets all over the place, and the control feedbacks are not bothered by the dust, ipso facto. So why do we need to care, or, to my regular complaint, waste taxpaters’ money funding someone with no useful work to do to care, and its not even real science, its modelling. FFS. Where is the value in this research for those paying for it? Pehaps they will propose a giant dust buster like Space Balls Mega Maid had, about as serious as their science.
ATMOSPHERIC CARBON DIOXIDE AND AEROSOLS:
Effects of Large Increases on Global Climate.
Abstract.
Effects on the global temperature of large increases in carbon dioxide and aerosol densities in the atmosphere of Earth have been computed.
It is found that, although the addition of carbon dioxide in the atmosphere does increase the surface temperature, the rate of temperature increase diminishes with increasing carbon dioxide in the atmosphere.
For aerosols, however, the net effect of increase in density is to reduce the surface temperature of Earth. Because of the exponential dependence of the backscattering, the rate of temperature decrease is augmented with increasing aerosol content. An increase by only a factor of 4 in global aerosol background concentration may be sufficient to reduce the surface temperature by as much as 3.5 deg.K. If sustained over a period of several years, such a temperature decrease over the whole globe is believed to be sufficient to trigger an ice age.
The rate at which human activities may be inadvertently modifying the climate of Earth has become a problem of serious concern . In the last few decades the concentration of CO2 in the atmosphere appears to have increased by 7 percent . During the same period, the aerosol content of the lower atmosphere may have been augmented by as much as 100 percent .
How have these changes in the composition of the atmosphere affected the climate of the globe? More importantly, is it possible that a continued increase in the CO2 and dust content of the atmosphere at the present rate will produce such large-scale effects on the global temperature that the process may run away, with the planet Earth eventually becoming as hot as Venus (700 deg. K.) or as cold as Mars (230 deg. K.)?
We report here on the first results of a calculation in which separate estimates were made of the effects on global temperature of large increases in the amount of CO2 and dust in the atmosphere.
It is found that even an increase by a factor of 8 in the amount of CO2, which is highly unlikely in the next several thousand years, will produce an increase in the surface temperature of less than 2 deg. K.
However, the effect on surface temperature of an increase in the aerosol content of the atmosphere is found to be quite significant. An increase by a factor of 4 in the equilibrium dust concentration in the global atmosphere, which cannot be ruled out as a possibility within the next century, could decrease the mean surface temperature by as much as 3.5 deg. K. If sustained over a period of several years, such a temperature decrease could be sufficient to trigger an ice age!
Schneider S. & Rasool S., “Atmospheric Carbon Dioxide and Aerosols – Effects of Large Increases on Global Climate”, Science, vol.173, 9 July 1971, p.138-141
Those results were based on a climate model developed by none other than James Hansen, incidentally.
Brianrlcatt ==> Is that you on a sailboat? My wife and I lived on our sailing cat in the Northern Caribbean for a decade…and some years we’d wake up in the morning with the decks covered with fine red dust — blown all the way from the Sahara.
“Northern” Caribbean? vs. Southern? So is that running drugs and illegals to the US mainland? :-). Just jealous….. is that where Necker is?
PS Is Key West worth a visit if you can’t sail, wife doesn’t like water, especially in large quantities
It was a Dutch 30m brigantine “The World’s Largest” built to do Hospitality, which had been to the Carribean.
https://www.oliviervanmeer.com/yachts/5783/50m-brigantine–swan-fan-makkum-.html
We went over to Cowes from the Solent in Cowes week, had a fun incident when some rich posh prick in a racing Yacht lost the give-way chicken game and was told to politely fuck off by our Captain. To applause.
My dad was Bosun of Marchwood Yacht Club in the Solent and had various sailing boats and a 50 ft Motor cruiser. I still like to sail a bit, cats are easier. Last exploit was a little RIB of the coast of Puerta de la Selva Spain. You are only allowed a little one w/o a licence. No money for real boats any more.
I do have a picture of me showing folk how to fall off the back of a massive 100 foot powered Cat in Antigua in the Sailing week, https://www.facebook.com/photo/?fbid=10154138753721458&set=a.10154138753781458
we also stood by while the Crew went assist to what had been a very nice single hull ocean Yacht that had planted itself on the jagged Atlantic side reef shoreline somehow, which was doing the vatnished underside no good at all while the owner tried to get the sails down….. before saing through an Ocean Yacht race! Still have some video. I taught my daughter how to sail in 2012 in Bodrum Turkey, It’s all a bit like my flying bum experiences… other people’s kit.
“The science is settled.” <– various media and PhD idiots
“There are some mistakes only someone with a Ph.D. can make.” Daniel Patrick Moynihan
“Science is the belief in the ignorance of the experts” – Richard Feynman
If sustained over a period of several years, such a temperature decrease could be sufficient to trigger an ice age!
Reminder – dust proposed as a ‘secret ingredient’…
Ralph Ellis: ‘Why did the ice-sheets melt, when there was no insolation increase?’
Summary here — https://tallbloke.wordpress.com/2015/10/11/albedo-regulation-of-ice-ages-with-no-co2-feedbacks/#comment-108295
I think the primary cause of this very unique interglacial event, when tropical climates are forced at the equatorial regions, is the asymmetry of the land masses in the SH and NH, as regards the effects of their very different heat capacities during the late glacial phase.
As Ralph, and others, have pointed out this event requires a unique Milankovitch configuration of max eccentricity co-incident with perihelion when the NH is most proximal to the Sun in the 23Ka precessionary cycle. Or, as nobody seems to say to make it easy for others, the Northern Hemisphere is as close to the Sun as it ever gets. Where the ice sheet is. Clue.
REPEAT: This is a unique configuration. A “full interglacial” ONLY happens under this condition of max eccentricity AND 23Ka maximum with the NH at perihelion to the Sun, NOT with SH at perihelion, or any other part?
Put another, heat input related way, to end a glacial, the NH has to be held closest to the Sun when the highest ever insolation occurs (and also the lowest in Winter). Whatever the balance of increased and reduced heat is, BANG! the ice is gone! In 7Ka.
That hemisphere has half the thermal capacity, so the temperature effect of +/- 40W/m^2 insolation variability will cause far greater temperature variability on it than the oceanic SH at perihelion and Apogee, obs. Warmer and colder, but net melty.
So the theory is that this asymmetry and the extremes it creates in the NH in response to y the high insolation variability at maximum eccentricity must somehow melt the ice caps in 7Ka, because the perihelion heating has a greater effect than the aphelion cooling on the NH.
We know the glacial phase ice sheet on the NH forms only where it is close to the oceans that supply the precipitation to build the lower latitude ice sheets, and also, from Radar measurements, that these ice sheets accumulate/decline in a very non-linear and even reversed manner with temperature. e.g. Total loss during the warmer Eemian interglacial, slow polar rate accumulation during the last glacial phase across NA and N. Europe down to 50 degrees N or so …. then maximum accumulation EVU recorded during Holocene optimum, then a slow net loss now as Earth cools from the Holocene, with a return to glacial rate net accumulation as in the last glacial to come later, as the current neo glacial gets steadily colder?
This is my theory, which is mine, extending the insights of Ralph Ellis, as regards HOW the asymmetric effects of extreme insolation variability on the Northern Hemisphere during the particular co-incidence of the eccentricity and precessionary cycles when the NH is proximal at perihelion is the main driver of interglacial events.
This also recognises the much-increased volcanic heating of the oceans by direct submarine volcanism at this time, probably by maximum solid tidal causes arising from orbital gravitational stresses, which, while overtly contributory and clearly naturally cyclic, lack the heat energy to be the dominant cause. http://dx.doi.org/10.2139/ssrn.4687577
Dust is not naturally cyclic, it is an effect of the glacial phase, expose ure of continental shelves and perhaps increasing volcanism. From whatever cause, the accumulating dust will contribute positive feedback with growing albedo reduction. NASA also notes that the published science has recorded the particular congruence of unique cyclic necessity for an interglacial event. So it must be twoo. S’obvious, innit?
nb: Contains only natural science, definite theories and observations. No models were harmed in validating this theory.
Aerosols and Their Importance – NASA
When absorbing aerosols such as soot or dust are deposited on snow or ice, they decrease its reflectivity (‘albedo’) and cause the surface to absorb more light, which has a warming effect. This can lead to, for example, faster retreat of glaciers.
https://earth.gsfc.nasa.gov/climate/data/deep-blue/aerosols