Extracted the book " Tahiti today and all these islands " by Arlette EYRAUD, with the editions J.A.
By through tropic of Capricorn (23° 27 south) between 144° and 152° of western longitude, the archipelago of Southern includes four high islands separated by distances from 150 to 200 km: Rurutu, Rimatara, Tubuai, Raivavae and the atoll of the Maria islands. More in the east and 27° 37 Sud Rapa which is low in latitude that the Easter Island, marks to 1300 km approximately of PAPEETE the southern land end of Polynesia in the Eastern part of the Southern Pacific
The influence of the latitude brings to these islands, without defense against the winds and the rains of the South, the temperatures lower of 4° than 8° Celsius compared to the islands of the Society and perhaps is this one of the reasons of the deceleration of the activity of the coral formations.
Rapa is deprived of reefs barriers and Rurutu has only one fringing reef with a few tens of meters of the shore.
Climatology is not either favourable with the fructification of the coconut whose output is poor and the breadfruit tree is rarer. On the other hand this moderate climate allowed, as of XVIIe century, the culture of the tarot in considerable quantity, then of sweet potato and, nowadays the development of European vegetables: onion, potatoes, cabbage, tomato, salad which feed the markets tahitiens.
