Tropic of Capricorn years. In South America, whilst in the continental cratons soils are almost as old as in Australia and Southern Africa, the presence of the geologically young and evolving Andes means that this region is on the western side of the subtropical anticyclones and thus receives warm and humid air from the Atlantic Ocean. As a result, areas in Brazil adjacent to the Tropic are extremely important agricultural regions, producing large quantities of crops such as sugarcane, and the natural rainforest vegetation has been almost entirely cleared, except for a few remaining patches of Atlantic Forest. Further south in Argentina, the
The HAB Theory The novel borrows heavily from Brown's theory and book, which is that approximately every 6,000–7,000 years the Earth's polar ice caps become over-burdened with ice, creating such an imbalance in the planet's center of gravity, that the Earth's poles and the Earth's equator shift positions. The former poles are soon located somewhere between the Tropic of Cancer and the Tropic of Capricorn, where the weight of the polar ice cap leaves a large circular depression and other dramatic geological changes occur as the huge quantity of water is released by the ice caps melting. Called "capsizing" in the novel the