The Azimuth Project


The idea

From Wikipedia:

Technically, an aerosol is a suspension of fine solid particles or liquid droplets in a gas. Examples are smoke, oceanic haze, air pollution, smog and CS gas.

In general conversation, aerosol usually refers to an aerosol spray can or the output of such a can. The word aerosol derives from the fact that matter “floating” in air is a suspension (a mixture in which solid or liquid or combined solid-liquid particles are suspended in a fluid). To differentiate suspensions from true solutions, the term sol evolved—originally meant to cover dispersions of tiny (sub-microscopic) particles in a liquid. With studies of dispersions in air, the term aerosol evolved and now embraces both liquid droplets, solid particles, and combinations of these.


The Devil are certainly in the details, concerning aerosol. Four decades of field trials have been performed initially on a per country basis and later on globally coordinated basis. The earliest 20 years found out (see the book by Kondratyev in the References):

the aerosols plays the most important role in atmospheric energy transformation processes, especially from the viewpoint of the transfer of short-wave solar radiation

They also concluded other important things in these early states of Aerosol field experiments and research:

  • Determination of the levels of background aerosol, e.g. the naturally occurring aerosols on Earth.
  • Modeling of clouds - as they have a large impact in climate processes - and aerosol modeling.

Climate effects

Qoute from Wikipedia:

Some anthropogenic aerosols, particularly sulfate aerosols from fossil fuel combustion, exert a cooling influence on the climate which partly counteracts the warming induced by greenhouse gases such as carbon dioxide. This effect is accounted for in many climate models. Recent research suggests that aerosol diffusion of light may have increased the carbon sink in the Earth’s ecosystem.


It is extremely difficult to estimate the overall effects of atmospheric aerosols on health. On one hand the tiny particles cause major public health problems, yet at the same time they are thought to cool the planet (evidence for this?) and thus they ward off global warming health diseases.

A verdict on their effect, if ever there is one, is well beyond the horizon for us now.


This quick note in the Health section is a summary of a Nature news piece.

The original paper is:

  • Löndahl, J. et al. Aerosol exposure versus aerosol cooling of climate: what is the optimal emission reduction strategy for human health?, Atmos. Chem. Phys. 10 (2010), 9441–9449.