single-climate worlds

Hope it's not a dumb question from a sad SF nerd again...
Planets with a major environment-type are common in science fiction (eg.
Tatooine: desert world, Dagobah: swamp world). Is it plausible for
(habitable) worlds to have one major type of environment, or is Earth
with many types of environment a more realistic model? Mars may be a
uniformly cold-desert planet (similar to the Tierra de Fuego?)--does it
have much environmental variation compared to Earth?
Note that I'm talking about habitable planets: many not-very-habitable
planets/moons like the Moon, Mercury, etc. are quite uniform if I'm not
mistaken.

Seb

"Seb" wrote in message
...
Hope it's not a dumb question from a sad SF nerd again...
Planets with a major environment-type are common in science fiction (eg.
Tatooine: desert world, Dagobah: swamp world). Is it plausible for
(habitable) worlds to have one major type of environment, or is Earth with
many types of environment a more realistic model? Mars may be a uniformly
cold-desert planet (similar to the Tierra de Fuego?)--does it have much
environmental variation compared to Earth?
Note that I'm talking about habitable planets: many not-very-habitable
planets/moons like the Moon, Mercury, etc. are quite uniform if I'm not
mistaken.

Seb

I'd expect inhabited worlds to have a "solvent" present in three phases
which
pretty much implies a very varied environment. Single sun planets with not
too inclined axes are going to have a significant variation in pole to
equator stellar
flux too. Extending Lovelock a bit you'd also expect a wide range of flora
and
fauna because of the stellar evolution cycle.

(Happy SF nerd)

"Newshound" wrote in message
...
| "Seb" wrote in message
| ...
| Hope it's not a dumb question from a sad SF nerd again...
| Planets with a major environment-type are common in science fiction (eg.
| Tatooine: desert world, Dagobah: swamp world). Is it plausible for
| (habitable) worlds to have one major type of environment, or is Earth
with
| many types of environment a more realistic model? Mars may be a
uniformly
| cold-desert planet (similar to the Tierra de Fuego?)--does it have much
| environmental variation compared to Earth?
| Note that I'm talking about habitable planets: many not-very-habitable
| planets/moons like the Moon, Mercury, etc. are quite uniform if I'm not
| mistaken.
|
| Seb
|
| I'd expect inhabited worlds to have a "solvent" present in three phases
| which
| pretty much implies a very varied environment. Single sun planets with not
| too inclined axes are going to have a significant variation in pole to
| equator stellar
| flux too. Extending Lovelock a bit you'd also expect a wide range of flora
| and
| fauna because of the stellar evolution cycle.
|

It is belived there have been times in the past when the earth's climate was
more uniform than now. In particular, ice ages of the sort we are now in a
stage of are a relatively rare phenomenon (although some in past epochs have
been more severe than the current one) because they seem to depend on a
favourable distribution of the continents either isolating a polar sea or
allowing a zonal current to isolate a polar continent from heat transport
from the tropics. The power of this heat transport is shown that even in
"ice age" conditions the inflow of warm North Atlantic water into the Arctic
Ocean basin can maintain open water up to 80N at Svalbard and for some
considerable distance along the Russian coastline.

Presumably the time will come, in a suitable number of millions of years,
when the gap between Greenland and Norway will open further and enable warm
water to completely invade the Arctic basin. A drifting of Antarctica away
from its current polar position, also blocking the South Circumpolar
current, would then mean an end to ice ages for a few tens or even hundreds
of millions of years. During these periods the "solid" phase will be
present only in the upper atmosphere or possibly on the highest mountains
apart from during night frosts.
--
- Yokel -
oo oo
OOO OOO
OO 0 OO
) ( I ) (
) ( /\ ) (

"Yokel" now posts via a spam-trap account.
Replace my alias with stevejudd to reply.

I don't see why it needs to exist as a solid. Why shouldn't life formed on
Earth had it been just too hot to have ice? I can see that with the
resulting lower amount of dry land it might have developed very differently.
That's not quite a "single-environment" Earth, but it's getting closer as
ocean in the dominant environment already. An all-ocean Earth would be very
different, of course. It certainly wouldn't have us!

"Newshound" wrote in message
...
I'd expect inhabited worlds to have a "solvent" present in three phases
which
pretty much implies a very varied environment. Single sun planets with not
too inclined axes are going to have a significant variation in pole to
equator stellar
flux too. Extending Lovelock a bit you'd also expect a wide range of flora
and
fauna because of the stellar evolution cycle.

(Happy SF nerd)