Set in an unspecified 'near-future' (one of the main characters has childhood memories of the Exxon Valdez disaster) in which a radical environmentalist movement, joined with a coalition of religious groups, has gained control of the US government and imposed draconian luddite laws which, in attempts to curb global warming, have ironically brought about the greatest environmental catastrophe in recorded history - an ice age which may eventually escalate into a Snowball Earth.

The exact process is described: Clouds are water condensation. This cannot occur without particulate matter in the atmosphere. The emission laws have removed most of this, reducing cloud cover, meaning the ground loses heat faster. This in combination with the drop in greenhouse gases has resulted in the acceleration of the existing ice age; now self-perpetuating as glaciers have a much higher albedo.

As a radical totalitarian environmentalist party now controls the US government, the scientific explanation is denounced as "propaganda from life-hating technophiles", and blame for the ice age is instead solely placed on the society surviving in orbit. Science fiction fandom forms the core of a pro-technology underground in the United States, working in tandem with Hacker movements. Other technologists - accused by the government of pursuing "materialist science" - were removed from their jobs and forced underground, where they were generally unable to continue their work. This rabid distaste for technology has resulted in the collapse of the economy and lack of education and a complicit media has left the majority of the population credulous and easily manipulated. The Greens have been in power for most of the lives of the characters.

As glaciers rapidly advance south, Canada and the northern United States are all but destroyed. Near the edge of the glaciers, in Milwaukee, barbaric feudal systems arise as the federal government and markets collapse, leaving violence and disease in their wake. In orbit, Mir and Space Station Freedom survive in tandem with a Lunar colony, but with no support from Earth. The city of Winnipeg is the last major outpost of Canadian civilization, warmed and inhabitable due to immense amounts of solar power beamed from the space stations.