Environmental Assessment
Volume B-3.4
Mine
Climate and Air Quality
Ambatovy Project
48
January 2006
3.4.4
Baseline Summary
Based on data from 1997 to 2004, hourly temperatures at the exploration camp
ranged from 7.6°C to 31.1°C with an annual average temperature of 17°C.
Annual average rainfall at the mine site was about 1,400 mm with almost 70%
occurring from December to March.
Figure 3.4-1 shows a windrose of data collected at the exploration camp from
1997 to 2004. The windrose consists of bars whose length indicates the
frequency of winds blowing from a given direction. The bars are also broken
into sections, each of which defines a speed range. A longer section indicates
that winds blow more frequently at a given speed for that direction. East-
southeast and southeast winds were predominant and occur 59% of the time
excluding calms. The average annual wind speed was 6 km/hr with maximum
hourly speeds of up to 48 km/hr and gust speeds over 80 km/hr. There was also a
high frequency of calm conditions (14.2%).
Figure 3.4-1 Observed Winds at Mine Exploration Camp
Calms: 14.2%
20%
15%
10%
5%
N
NNE
NE
ENE
E
ESE
SE
SSE
S
SSW
SW
WSW
W
WNW
NW
NNW
1-5
6-11
12-19
20-29
>30 km/hr
