User Guide

OCEANOGRAPHY
At over 20% higher insolation than Earth, Planet has very small polar ice caps.
The effect of this on the oceanic circulation is profound. Instead of cold oxy-
gen-rich polar water sinking at the poles and being carried in a current along
the ocean floor to the equator (as on Earth today), the circulation is driven in
reverse, with warm saline oxygen-poor water sinking at the equator and flow-
ing to the poles. As a result, the bottom waters have little oxygen.
SOIL COMPOSITION
Compared to Earth, silicates are much less common in the soils of Planet. As
in the tropics on Earth, warm water leaches the silica from clays, leaving a poor
alumina-rich soil. (This does not prevent rain forests from growing, but will
inhibit agriculture.) The arctic regions have a higher proportion of acidic soils
with a high proportion of organic matter (podzols) which is equally hard to
farm. The temperate soil zone, which on Earth is favoured with rich alumi-
nosilicate clays, is much narrower on Planet, and the soils are more likely to
be sandy or lime-rich. Bogs are also common.
ECOLOGY
Although basically similar to Earth life, in that it is based on carbon com-
pounds in water, the organisms of Planet have evolved a biochemistry very dif-
ferent from Earth. The scarcity of carbon in the environment, and of dioxygen
in the soil, has forced plants to try to make do without O2 (oxygen), and to
economize on the use of carbon in structural parts and as an energy storage
material. They do this by using a biochemical reaction unknown on Earth.
Planet’s plants seem to have a special enzyme to encourage this reaction, pos-
sibly with the aid of sunlight. They use the nitrate obtained this way to store
energy as organic nitro-compounds, to reduce carbonates to carbon, and to
carry out respiration in anoxic environments.
A NEW SUN
APPENDIX 5
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