ATOC 4720: class 17 - PowerPoint PPT Presentation

Atoc 4720 class 17
1 / 15

  • Uploaded on
  • Presentation posted in: General

ATOC 4720: class 17. Atmospheric aerosols Effects on atmospheric phenomena. Total concentration. Concentration vary with location and time. Generally,. Over the ocean:. Rural land areas:. Polluted air:. >10km, H=7km; <5km, H=3km. Size spectra. <0.2um ;. 0.2-2um; >2um. Similar.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Presentation

ATOC 4720: class 17

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Atoc 4720 class 17

ATOC 4720: class 17

  • Atmospheric aerosols

  • Effects on atmospheric phenomena

Total concentration

Total concentration

Atoc 4720 class 17

Concentration vary with location and time.


Over the ocean:

Rural land areas:

Polluted air:

>10km, H=7km;

<5km, H=3km.

Size spectra

Size spectra





Atoc 4720 class 17

Sources and sinks:

Aitken nuclei


Combustion processes (human activities,

Forest fires, volcanoes, gas-to-particle


[2] Large to giant aerosol:

wind blown dust, emission of pollens,

and spores from plants; Ocean: bursting of

Air bubbles (under high windspeed); urban

Industrial processes.

Atoc 4720 class 17

Sinks: Aitken nuclei--big aerosols:

Precipitation and gravity.

Global: Precipitation 80-90%;

10-20%: gravitational settling.

Aitken nuclei: <1hour in polluted

Air or in clouds;

Large: days;

Giant: minutes-hours-days.

Life time:


Atoc 4720 class 17

Average Residence Time of Aerosols in Atmosphere

Atoc 4720 class 17


Desert Aerosol Transport over North Africa and the Mediterranean.

The 2D distribution of aerosols

Concentration for the period

from August, 1996 to April, 2000 (top panel).

Main source regions of the UV-absorbing aerosols can be inferred, and these regions are marked in the bottom panel.

Atoc 4720 class 17

Desert Aerosol Transport over North Africa and the Mediterranean.

Largest values

Tend to be along

The dust plume


Effects on atmospheric phenomena

Effects on atmospheric phenomena

[1] Clouds and precipitation:

Good: Precitaion; bad: acid rain

Atoc 4720 class 17

[2] Electricity: electric field

and conductivity;

measurements of

electricity may indicate aerosol


Atoc 4720 class 17


Electric field

Atoc 4720 class 17

[3] Radiation

Scattering & absorption of solar radiation:

Important for the earth’s radiation budget;

Qr at the earth’s surface can cause

SST (sea surface temperature) variability,

And thus force variability in atmospheric

Circulation and convection: affecting


Atoc 4720 class 17

[4] Chemistry:

Liquid aerosol absorbs gases: react;

Solid aerosol provide surfaces upon which

Gases can be absorbed and react;

Aerosol & sulfur dioxide from polluted air

accumulate in stable (T-inversion),

moist air==sulfur dioxide is converted

to sulfates==smog;

1952 Landon smog caused 4000 people death.

  • Login