Geography Climate of Rio

The city of Rio occupies the western margin of the Bay of Guanabara and some of its islands (such as Governor and Paqueta). Rio de Janeiro was developed on narrow flood plains compressed between mountains and hills.

The mountain of the Sea, at the Atlantic edge of the plateau, rises to the northwest, and is about 40 kilometers from the coast and interior of the mainland. The Pedra da Gavea, one of the greatest rock elevations of the city, is the largest block of stone by the sea on the planet, with 842 meters of altitude.

Rio de Janeiro has three mountainous areas. Pedra Branca, which crosses the city east to west (where the municipality peaks at 1024 meters); Gericino to the north (with the peak of Guandu at 900 meters); and the Tijuca or the Carioca, bursting with hills and peaks, some covered with lush vegetation that are of great tourist interest.

The peaks in this area include the peak of Tijuca (1,022 m), of the Nozzle Papagaio (975 m), the Andaraí (900 m), the Pedra da Gavea (842 m), [15] the Corcovado (704 m), the Two Brothers (533 m) and Sugar Loaf (395 m) which is the entrance to the bay.

Its coastline is 197 kilometers long, includes more than 100 islands occupying 37 square km, and breaks down into three parts, devoted to Sepetiba Bay, the Atlantic Ocean and the Bay of Guanabara. The coast of Sepetiba has the unique expression of the Restinga da Marambaia, and is sandy and a little low cut.

The coast of the Bay of Guanabara is cut, covers many islands (such as the Governor at 29km ², and Local Galeao International Airport) and on its banks, is the commercial center and industrial suburbs. The Atlantic coast alternates considerably, presenting either high, as when in contact with the ramifications of the massive coastal areas of Pedra Branca and Tijuca, or presenting low, such as the passage through which run the beaches of Copacabana, Ipanema, Leblon, Barra da Tijuca and Recreio dos Bandeirantes.

Several lakes, such as the Tijuca, Marapendi, Jacarepagua and Rodrigo de Freitas formed from runoff form the mountains, and much of the swampland is still not completely drained.

Climate
The climate is classified as tropical Atlantic (Aw), following the model of Koppen, with and average annual temperature is 23.1 ° C.

As a coastal city, the effect of the water is quite noticeable, translating into relatively low temperature ranges. The average monthly high temperature is 26.1 ° C and the average monthly low is 20 ° C. The mean annual absolute maximum and minimum temperatures measured in each month are, respectively, 36.2 ° C and 13.8 ° C. July is the coldest month, with average maximum and minimum of 24 ° C and 17 ° C respectively, and January, the hottest (29 ° C and 23 ° C).

The summers are marked by hot and humid days, eventually surpassing a high of 40 ° C in isolated spots, while the winters tend to be mild and the rainfall more restricted, with a minimum temperature rarely below 10 ° C. In general, the year can be divided into two seasons: one relatively warm and wet, and the other of mild temperatures. The characteristics are of spring and fall.

Due to the high concentration of buildings in central urban areas, more distant from the coast, there is the common appearance of islands of heat, with temperatures surpassing 40 ° C in the warmest months of the year. In these and other areas, you can see some differences in degrees Celsius relative to coastal areas, due to sea breezes. The amount of accumulated annual rainfall is 1086 mm. The rains are concentrated in the months of December, January, February and March, becoming sparser in the period June to August. It rains about one third of the time. October, November and January each average 13 days of precipitation.

December averages 14 days; February and September, 11 days; and June, July and August, 7 days. However, the bulk accumulation of precipitation is observed in December (137 mm), January (125 mm), February (122 mm) and March (130 mm).

In the summer, landslides on the slopes of the city are not uncommon, sometimes causing fatalities.

Relative humidity shows acceptable rates throughout the year. The average in the period preceding the mid-day is at 84.6% and, after the twelve hours, 70.8%. June, July and August have the lowest percentage in the afternoon: 69, 68 and 66% respectively