Turks and Caicos Islands

Table 3.3.4: GCM and RCM projected changes in Turks and Caicos under the A2 scenario
3.4. Wind Speed
19
Projected changes by the 2080s
SRES A2
Min Median Max
GCM Ensemble Range -63
% Change
-8 5
Annual RCM (ECHAM4)
2
RCM (HadCM3)
-35
GCM Ensemble Range -34 1 36
DJF RCM (ECHAM4)
33
RCM (HadCM3)
4
GCM Ensemble Range -54 -24 14
MAM RCM (ECHAM4)
0
RCM (HadCM3)
-36
GCM Ensemble Range -85 -30 0
JJA RCM (ECHAM4)
-36
RCM (HadCM3)
-67
GCM Ensemble Range -73 -1 20
SON RCM (ECHAM4)
12
RCM (HadCM3)
-43
Observed mean wind speeds from the ICOADS mean monthly marine surface wind dataset demonstrate
increasing trends around Turks and Caicos Islands in all seasons over the period 1960-2006. The increasing
trend in mean annual wind speed is 0.34 ms -1 per decade. It is greatest in DJF at the rate of 0.56 ms -1 per
decade.
Mean wind speeds over Turks and Caicos Islands generally show a very small increase in GCM projections.
Projected changes in annual average wind speed range between -0.2 and +0.5 ms -1 by the 2080s across the
three emission scenarios. Both increases and decreases are seen in all seasons across the 15-model
ensemble.
RCM projections based on two driving GCMs lie within the range of changes indicated by the GCM
ensemble. RCM simulations project a decrease in wind speed in DJF and increases in MAM and JJA seasons.
Driven by ECHAM4, the RCM indicates a very small change in wind speeds in all seasons. Driven by
HadCM3, the RCM projects a relatively large decrease of 0.5 ms -1 in DJF wind speed and a large increase of
0.7 ms -1 in JJA wind speed by the 2080s.