Climate French Guiana
The ideal is obviously to visit the department during the summer months: the period from the end of July to the end of October corresponds to the dry season, a blessed period to venture into the forest as well as to enjoy the coastline. The small rainy season, which extends roughly from Christmas to carnival (February), nevertheless reserves some beautiful sunny days, just like "the small summer of March". All in all, thanks to its hot and humid equatorial climate (it is always between 26°C and 30°C) and the absence of hurricane risk, French Guiana can be visited all year round, except perhaps in June, the rainiest month. However, threats linked to global warming are weighing down on the future of French Guyana here as elsewhere: rising land and sea temperatures, rising water levels and rainfall hazards could well have serious impacts on the daily life of the department.
Guyana Seasonality
Two types of seasons - dry season and rainy season - punctuate the passage of the Guyanese year in four stages.
A strong rainy season runs from April to June, which is not a good time to visit the department because roads become impassable (potholes, floods, etc.). The long hours of rain do not allow for dugout canoe trips or walks in the forest, and often the month of June, the rainiest, is the occasion for the annual closures of businesses.
Then comes the dry season from mid-July to early November, certainly the best time - it's hot (30°C) and the humidity drops - to travel to French Guiana, then dressed in its finest finery: blue sky, green forest and waterlogged rivers. The tracks are then passable, and it is possible to penetrate the interior of the country by pirogue or on foot. However, at the end of the dry season, the rivers, whose water level drops sharply, may not be able to be fully recovered.
Immediately afterwards comes another short, more pleasantrainy season, which generally lasts from mid-November to February. The rains then return and the level of the rivers rises, making French Guiana a destination of choice in the heart of the metropolitan winter. It is then necessary to plan for a little protection from the rain and give priority to the coast and the west of French Guiana, where the rains are less frequent.
Themonth of March, finally, brings with it the "little summer of March", a welcome break in the heart of the wet season: before March, it rains a little, after March, it rains a lot, even if sometimes the climate does not always follow the calendar very closely. It is worth noting that in the forest, even if the temperatures are relatively constant throughout the year, the difference between those of the day and those of the night can be surprising. The variations are of the order of ten degrees, which is why it is necessary to cover yourself well at night, when you sleep in a hammock (sleeping bag, blanket).
It shouldalso be noted that the Guyanese territory is sheltered from the passage of Caribbean cyclones. This can be explained by the weakness of the Coriolis force in the equatorial regions, which is essential for the formation of cyclonic phenomena. However, a cyclone in northern Guyana can cause intense thunderstorms.
The impact of global warming
The department is not spared from air pollution caused by coastal development. But it is perhaps global climate change that is likely to pose the greatest challenge. Although the impacts are difficult to assess, the measurements taken over the last fifty years in the region are unequivocal. Over the period 1955-2009, an increase in average temperatures of the order of +1.36°C was observed. Also, a study conducted between 1993 and 2012 off the coast of French Guyana reported a rise in water levels at an average rate of 3.5 mm/year, a rate slightly higher than the global rate. Finally, rainfall is increasingly variable. As a result, meteorologists are predicting longer droughts and much more extreme rainfall periods for the entire eastern Amazon region. Among the most concrete threats are the risk of submergence of inhabited areas, but also land movements. Warming waters can also cause changes in the distribution range of fish, impacting the fishing sector, while more erratic rainfall can affect the quality of the soil and thus of agriculture as a whole.
