What's new
A Planet That Pushes Back
The map is not scenery any more.
Hurricanes
Coastal cities in the equatorial jungle band and the two desert belts face tropical storms, hurricanes and super-typhoons. Warming makes them more frequent and more severe. A Sea Platform ends the super-typhoons and keeps your buildings standing. See Hurricane.
Disasters
Earthquakes near hills, floods along unwalled rivers, plague and fire in cities without an Aqueduct, famine without a Granary, pirates on undefended coasts. Each one has a local cause, and almost every cause has a cure you can build. See Disasters.
Warming
Warming is scaled to the size of the map, so an epic world warms on the same schedule as a small one. You can fight it: the Kyoto Accord, Carbon Capture, and an Environmental Advisor that shows which of your cities are smoking and which cures each one already has.
Warming has one more consequence, which only matters if somebody out there is watching. See the Scavengers.