Geography of Brazil clearing. Public policies intended to promote sustainable management of timber extraction, as well as sustainable use of nontimber forest products (such as rubber, Brazil nuts, fruits, seeds, oils, and vines), were being discussed intensely in the mid-1990s. However, implementing the principles of sustainable development, without irreversible damage to the environment, proved to be more challenging than establishing international agreements about them. Although 90% of the country is within the tropical zone, the climate of Brazil varies considerably from the mostly tropical North (the equator traverses the mouth of the Amazon) to temperate zones below the Tropic of Capricorn (23°27' S
Daytime of the Equator. Within this zone, the Sun will pass (or culminate) almost directly overhead on at least one day per year. The line of 23.5° north latitude is called the Tropic of Cancer, because when it was named, the Sun passed overhead at this location at the time of year when it was within the zodiac sign of Cancer. The equivalent line of south latitude is called the Tropic of Capricorn, for similar reasons. If they had been named today using the constellation in which the sun is currently in at the time it is directly overhead the tropic