An equatorial climate is usually one in which rainforests can be found due to the year-round humidity and precipitation. There is no winter season and no period in which it is particularly dry. Rainfall is usually heavy and frequent all through the year, yielding dense, luscious vegetation typical of rainforests. Night time temperatures may drop significantly from daytime highs. However, the daily temperatures are all fairly similar as equatorial zones usually lie on the equator (although this is not always the case), placing them on the same line of latitude and, therefore, along the same pressure belt. Because it is usually overcast in equatorial zones, the daily highs do not often exceed about 33 degrees Celsius, and are usually at a comfortable temperature between 25 and 28 degrees.
Lighting lights up the night sky at Salvador of Bahia - Brazil.
As its name implies, this climatic zone is found in the tropics. The temperatures of these zones are consistent all year round. In fact, the only distinguishing characteristic of the different seasons is the amount of rainfall that they bring. In areas of rainforests, such as in Brazil, the average rainfall is at least 60 millimetres (or 2.4 inches) per annum. To qualify as a Tropical Zone, an area must have a mean temperature of over 18 degrees Celsius all year round.
These zones receive less rain than they actually need to make up for evaporation, but not so much less that the area becomes a desert. They are the halfway mark between deserts and humid forests. In semi-arid zones, the vegetation includes hardy shrubs and grasses, rather than trees. There are"hot semi-arid climates" and "cold semi-arid climates", each with their own unique characteristics based on the differences in the mean annual temperature.
This is also called an Oceanic Climate or a Maritime Climate and is found along the coast of Brazil. It is characterised by cool summers and warm winters, although the annual temperature does not vary by significant amounts. Rainfall is fairly uniform throughout the year. To qualify as such a zone, the area must experience an annual mean temperature of not lower than 18 degrees Celsius.
This zone refers to the areas that are just outside of the formal Tropical Zones. It is hot, but not quite as hot and humid as Tropical areas. Winters are mild to cool, but not cold enough for snow or frost. In Brazil, the Subtropical Zone experiences different levels of rainfall, depending on their elevation above sea level.
In general, the coastal cities of this South American country can get very hot, while those on plateaus usually enjoy milder temperatures and conditions. Northeast Brazil is the driest part of the country, yielding limited vegetation, while the Amazon Basin experiences the highest levels of precipitation and is, therefore, home to an array of fascinating fauna and flora.
Here is a web site with details on Brazil's climate: http://www.brcactaceae.org/climate.html