Saturnus' nordpol.
Nu sitter kag och tittar på tv. Om 30 minuter ska jag dra iväg till jobbet. Ska följa med en äldreboende till sjukhuset.
Så det får bli en video. Vad säger ni om denna? Det är första gången jag ser den här videon.
Update: Kom hem precis(16,30), och är TRÖÖTT! Ska till observatoriet om 30 minuter nu, så jag tänker bara vila mig. Ses ikväll istället:)
Henrik
Saturnus "polar vortex". Höll ett föredrag om olika sådana runt om i solsystemet i en kurs i atmosfärfysik. Måste leta rätt på det och se vad jag skrev =)
13:47:27
Assi
Skumt :S. Du får gärna berätta mer om detta fenomen :) intressant. om du orkar såklart
17:16:21
Henrik
Ok, det här är en sammanfattning om 'Polar Vortex' från det föredraget, utan bilder dock. Det börjar med en förklaring om vad Jordens vortex är för något och dess betydelse, sedan beskrivs några liknande formationer på andra planeter i solsystemet. Hoppas det förklarar litegrann... =)
-----------------------------------
This presentation deals with the subject of the polar vortex: its formation,
climatological impact and the discoveries of similar structures elsewhere in the
solar system.
The Earth’s polar vortices and its formation
The polar vortex is a large- scale cyclone located near the Earth’s poles, in the stratosphere and upper troposphere. It forms during the hemisphere’s winter, when no sunlight heats the polar region. Strong circumpolar winds, the polar night jet, develop that isolates the cold air nearest the poles. The vortex is strongest during the winter
and early spring for the hemisphere. At these times, air from outside the vortex
cannot mix with the air inside it. The trapped air continues to cool of radiatively
and thus becomes very cold.
Climate impacts
One phenomenon that is found in the polar regions is
polar stratospheric clouds, PSCs. They form at very low temperatures, below -
80◦ C . These clouds are more common over Antarctica than in the Arctic, since
temperatures are below -80 ◦ C for longer periods. On the surface of PSCs,
chlorine and bromine compounds are converted into active forms. These then
act as a catalyst in the destruction of the ozone layer. In the Antarctic, this
leads to the creation of an ozone hole.
Discoveries of polar vortices on other planets
Polar vortices have been discovered on other planets as well. This have led scientist to search for similarities and differences with the vortices on Earth. The origin and the dynamics of these systems are not so well understood, and more research is needed. The
study of vortices on the giant planets Jupiter and Saturn does not have to
consider the effects of topography, but similarities with the Earth can still be
found.
Venus
Mariner 10, en route to Mercury, found evidence of a vortex above
the south pole of Venus in 1974. In 1979, the spacecraft Mariner Venus discov-
ered a similar feature in the northern hemisphere. The most interesting aspect
of Venus’ vortices is that the atmosphere rotates much faster than the planet
itself.
Jupiter
Images of Jupiter’s north polar region shows an almost hexagonal
shape that extends vertically from the stratosphere down into the top of the
troposphere. As on Earth, a steep temperature gradient creates a strong cir-
cumpolar wind that keeps the polar air isolated from the rest of the atmosphere.
Saturn
Polar vortices have been discovered at both poles of Saturn. At the north pole, there has been found a hexagonally shaped structure, as on Jupiter. The hexagonal structure is very persistent, in spite of large differences in insolation. This suggests that it might originate from inside the troposphere.
What is more interesting is the vortex found at the south pole. It is the first ever
discovered where the vortex air is warmer than the surrounding air. Though
the southern hemisphere had been subjected to continous sunlight for over 15
years at the time of this discovery, this does not explain why the polar vortex
is so much warmer than the air at lower latitudes.
-----------------------------------
14:02:35