Turks and Caicos Islands

Relative humidity data has not been made available for all models in the 15-model ensemble. From the
available data, the GCM projections indicate a small increase in RH in all seasons. The ensemble sub-sample
range does span both increases and decreases in RH in all seasons.
RCM projections indicate small increases in RH over Turks and Caicos Islands in all seasons. But, these
increases are generally smaller in the EHCAM-driven simulation and higher in the HadCM3-driven
simulation than the GCM ensemble median projections. RCM simulations, in general, project around 1%
increase in annual RH by the 2080s under the A2 scenario.
The representation of the land surface in climate models becomes very important when considering
changes in relative humidity under a warmer climate. This factor is reflected when GCMs and RCMs
projections are compared.
Table 3.5.1: Observed and GCM projected changes in relative humidity for Turks and Caicos Islands
Observed
Mean
1970-99
Turks and Caicos Islands: Country Scale Changes in Relative Humidity
Observed
Trend
1960-
2006
Projected changes by Projected changes by Projected changes by
the 2020s
the 2050s
the 2080s
Min Median Max Min Median Max Min Median Max
(%) (change in
% per
decade)
Change in % Change in % Change in %
A2
0.2
0.6
1.2
Annual 78.9 -0.14 A1B -3.9 0.1 0.7 -3.8 0.3 1.3 -4.6 0.2 1.6
B1 -3.8 -0.3 0.3 -3.5 0.2 1 -4 0.6 1.1
A2
0
0.7
0.9
DJF 77.7 0.22 A1B -2.8 -0.3 1 -3.3 0.5 1.2 -4 0.5 2.1
B1 -3.2 0 0.9 -1.4 0.2 1.1 -3 0 1.6
A2
0.3
0.8
1.3
MAM 79 -0.25 A1B -4.7 0.4 0.7 -4 0 1.4 -4.7 0.2 2
B1 -4.5 -0.2 0.7 -4.2 0.5 0.8 -4.5 0.5 1.5
A2
0
0.4
1.5
JJA 80 -0.2 A1B -3.9 -0.3 0.6 -4.2 0.4 1.3 -5.1 -0.5 1.6
B1 -3.5 -0.5 0.4 -4.3 0.4 0.8 -4.6 0.5 1.8
A2
0
0.5
1.2
SON 78.7 -0.33* A1B -4.1 0.1 0.8 -3.6 -0.1 1.3 -4.8 -0.8 1.8
B1 -4 -0.3 0.4 -3.9 -0.2 1.1 -3.7 0.2 1.4
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