“Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A...
Transcript of “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A...
![Page 1: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/1.jpg)
“Diamond dust”:
A very thin ice-cloud
in the near-surface
inversion layer.
![Page 2: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/2.jpg)
“Diamond dust”:
A very thin ice-cloud
in the near-surface
inversion layer.
It’s a mixing-cloud.
(Saturation vapor
pressure as a function
of temperature is
concave-upward.)
![Page 3: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/3.jpg)
Snow crystals falling in winter at South Pole (temperature –60 C).
Small grid is 50 microns. Photo by Steve Warren.
![Page 4: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/4.jpg)
![Page 5: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/5.jpg)
Shimizu crystals (~ 10 µm × 1 mm)
![Page 6: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/6.jpg)
![Page 7: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/7.jpg)
Nacreous clouds (Polar Stratospheric Clouds, PSC)
above McMurdo Station (78°S), September 2009
![Page 8: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/8.jpg)
Snow accumulation
(centimeters liquid equivalent
per year):
East Antarctic Ridge 2-3
Peninsula >40
Average for Antarctica ~17
Global average 100 cm
(40 inches)
![Page 9: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/9.jpg)
Snow accumulation
(centimeters liquid equivalent
per year):
East Antarctic Ridge 2-3
Peninsula >40
Average for Antarctica ~17
Global average 100 cm
(40 inches)
At South Pole (7 cm/yr), a
large fraction of the snowfall
comes from a few warm
storms.
On the East Antarctic Ridge
(2 cm/yr), most may come
from diamond-dust.
![Page 10: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/10.jpg)
Snow accumulation
(centimeters liquid equivalent
per year):
East Antarctic Ridge 2-3
Peninsula >40
Average for Antarctica ~17
Global average 100 cm
(40 inches)
At South Pole (7 cm/yr), a
large fraction of the snowfall
comes from a few warm
storms.
On the East Antarctic Ridge
(2 cm/yr), most may come
from diamond-dust.
During the last ice age: Lower
temperature, less snowfall.
With future global warming:
Probably more snowfall.
![Page 11: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/11.jpg)
Wind direction at the surface
Wind
![Page 12: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/12.jpg)
Wind direction at the surface
Average wind speed
South Pole
summer 8 knots
winter 13 knots
Cape Denison
annual 40 knots
Threshold for drifting snow
~ 14 knots
![Page 13: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/13.jpg)
![Page 14: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/14.jpg)
![Page 15: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/15.jpg)
Blowing snow (as well as a few falling-snow crystals)
![Page 16: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/16.jpg)
![Page 17: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/17.jpg)
![Page 18: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/18.jpg)
![Page 19: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/19.jpg)
![Page 20: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/20.jpg)
![Page 21: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/21.jpg)
Climate changes
(1) Mean annual temperature
South Pole Antarctic Peninsula (west side)
Turner 2004
![Page 22: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/22.jpg)
Climate changes
(2) Wind speed
Late winter (July-Sept)
South Pole
Annual
Lazzara et al. 2012
![Page 23: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/23.jpg)
Climate changes
(3) Snow accumulation
South Pole
![Page 24: “Diamond dust”: A very thin ice-cloud in the near-surface ...€¦ · “Diamond dust”: A very thin ice-cloud in the near-surface inversion layer. “Diamond dust”: A very](https://reader036.fdocuments.us/reader036/viewer/2022081621/61299d0727f5703f287f3ccd/html5/thumbnails/24.jpg)
Antarctica
Depth of ice: average 2.2 km, maximum 4.8 km
About 86% of the ice is in East Antarctica
Mean annual temperature
from -60°C on East Antarctic Plateau
(Vostok, Dome C, Plateau Station)
to -3°C on Antarctic Peninsula
Temperature extremes at surface
World record low temperature: -89°C (at Vostok)
Record high temperature at South Pole: -12°C
Snow accumulation
average 14-19 g cm-2 yr-1
on Plateau 5 g cm-2 yr-1