Journal of Energy Bioscience 2012, Vol.3, No.1, 1-12
8
Table 2 Correlation coefficients and interpretation
(
SAMHSA, 2011,
_ 4_ pg9. htm)
Correlation coefficient (r)
Strength of correlation
IMD sites considered for re-validating CRU data
0.90 - 1.00
Very high
Sundernagar
0.70 - 0.89
High
Bilaspur, Nahan, Bhuntar
0.40 - 0.69
Moderate
Chamba, Dharmshala, Dalhousie, Manali, Shimla CPRI
0.20 - 0.39
Low
-
0.00 - 0.19
Negligible
Shimla
Figure 7 Cross-comparison of synthesised monthly wind speed data
(
Mani and Mooley, 1983). For re-validation of the
apparent representative wind data, CRU data within
10
km radius of ten IMD sites with surface data
availability were considered (represented in Figure 3).
CRU and IMD monthly wind speed values were
compared for these sites using scatter plots
(
represented in Figure 8). Out of 10, 1 site
(
Sundernagar) showed very high, 3 sites (Bilaspur,
Nahan, Bhuntar) showed high and 5 sites (Chamba,
Dharmshala, Dalhousie, Manali, Shimla CPRI)
showed moderate correlation between measured IMD
and synthesised CRU values (Table 2). The undulating
terrain of Himachal Pradesh renders variations in wind
speeds even over small distances and hence explains
the absolute lack of correlation between IMD and
CRU values in Shimla.
The above findings reiterate that CRU wind speeds are
the most representative among the three synthesised
datasets collected. CRU model considers geographical
influences and high resolution makes it prudent for
meso-scale (10~100 km) seasonal wind profiling in
the tough Himalayan terrain of Himachal Pradesh.
4.2
Seasonal wind profiling
Seasonal wind profiles for Himachal Pradesh based on
CRU data were generated by Kriging interpolation
Figure 8 Correlation analysis for re-validation of CRU data
within 10 km radius of IMD sites with surface data availability
method in a geospatial application. Figure 9 shows the
seasonal as well as spatial variation of average wind
speeds. Frequency of occurrences of regional wind
speeds are represented by histograms. As observed
in the annual CRU wind regime (Figure 6), the spatial
variations of wind speeds in seasonal wind profiles
(
Figure 9) were explicitly influenced by elevation and
resultant agro-climatic zones. Highest wind speeds in
