Monthly prediction of rainfall over India and its homogeneous zones during monsoon season: a supervised principal component regression approach on general circulation model products

This research used CFSRv2 data as output data general circulation model. CFSRv2 involves some variables data with high correlation, so in this research is using principal component regression (PCR) and partial least square (PLS) to solve the multicollinearity occurring in CFSRv2 data. This research aims to determine the best model between PCR and PLS to estimate rainfall at Bandung geophysical station, Bogor climatology station, Citeko meteorological station, and Jatiwangi meteorological station by comparing RMSEP value and correlation value. Size used was 3×3, 4×4, 5×5, 6×6, 7×7, 8×8, 9×9, and 11×11 that was located between (-40) N - (-90) S and 1050 E -1100 E with a grid size of 0.5×0.5 The PLS model was the best model used in stastistical downscaling in this research than PCR model because of the PLS model obtained the lower RMSEP value and the higher correlation value. The best domain and RMSEP value for Bandung geophysical station, Bogor climatology station, Citeko meteorological station, and Jatiwangi meteorological station is 9 × 9 with 100.06, 6 × 6 with 194.3, 8 × 8 with 117.6, and 6 × 6 with 108.2, respectively.

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Variations in sulphate aerosols concentration during winter monsoon season for two consecutive years using a general circulation model

Atmósfera ◽

10.1016/s0187-6236(13)71082-8 ◽

2013 ◽

Vol 26 (3) ◽

pp. 359-367 ◽

Cited By ~ 1

Author(s):

S. Verma ◽

O. Boucher ◽

H.C. Upadhyaya ◽

O.P. Sharma

Keyword(s):

General Circulation Model ◽

General Circulation ◽

Monsoon Season ◽

Circulation Model ◽

Winter Monsoon ◽

Sulphate Aerosols

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Impact of absorbing aerosols on the simulation of climate over the Indian region in an atmospheric general circulation model

Annales Geophysicae ◽

10.5194/angeo-22-1421-2004 ◽

2004 ◽

Vol 22 (5) ◽

pp. 1421-1434 ◽

Cited By ~ 18

Author(s):

A. Chakraborty ◽

S. K. Satheesh ◽

R. S. Nanjundiah ◽

J. Srinivasan

Keyword(s):

General Circulation Model ◽

General Circulation ◽

Monsoon Season ◽

Lower Troposphere ◽

Circulation Model ◽

Indian Region ◽

Radiative Heating ◽

Aerosol Forcing ◽

Absorbing Aerosols ◽

The Impact

Abstract. The impact of anthropogenic absorbing aerosols (such as soot) on the climate over the Indian region has been studied using the NCMRWF general circulation model. The absorbing aerosols increase shortwave radiative heating of the lower troposphere and reduce the heating at the surface. These effects have been incorporated as heating of the lower troposphere (up to 700hPa) and cooling over the continental surface based on INDOEX measurements. The heating effect is constant in the pre-monsoon season and reduces to zero during the monsoon season. It is shown that even in the monsoon season when the aerosol forcing is zero, there is an overall increase in rainfall and a reduction in surface temperature over the Indian region. The rainfall averaged over the Tropics shows a small reduction in most of the months during the January to September period. The impact of aerosol forcing, the model's sensitivity to this forcing and its interaction with model-physics has been studied by changing the cumulus parameterization from the Simplified Arakawa-Schubert (SAS) scheme to the Kuo scheme. During the pre-monsoon season the major changes in precipitation occur in the oceanic Inter Tropical Convergence Zone (ITCZ), where both the schemes show an increase in precipitation. This result is similar to that reported in Chung2002. On the other hand, during the monsoon season the changes in precipitation in the continental region are different in the SAS and Kuo schemes. It is shown that the heating due to absorbing aerosols changes the vertical moist-static stability of the atmosphere. The difference in the precipitation changes in the two cumulus schemes is on account of the different responses in the two parameterization schemes to changes in vertical stability. Key words. Atmospheric composition and structure (aerosols and particles) – Meteorology and atmospheric dynamics (tropical meteorology; precipitation)

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