Why is Chickamaglur, Medikiri receiving less rains since last 5 years?

1. Though not five years, it is this SWM 2010 period that the catchment areas of River Cauvery is getting lesser rainfall.
You know that the mean latitude where the SWM will be active is about 15 degree parallel. But this year [2010] the cross equatorial flow in Arabian Sea is stronger in such a way it touched first Goa, Maha, Guj & Rajastan areas right from the early days of on set.
2. The traditional off shore trough that used to prevail in Arabian Sea from Lakeshawadeep to Maharashtra was mostly absent or seen in the upper latitudinal areas only.
3. Further the monsoonal winds were [& are too] stronger above 850 hPa level. This leads, many a times, the moisture laden winds to cross the western Ghats / penetrate Himalayas. Similarly, one of the attributed reasons for heavy rainfall in LEH area was also due to this.
4. The conventional monsoon trough from Ganga Nagar to Head Bay was not prominent most of the time.
5. Similarly monsoon depression in the Bay was less.
6. [As pointed out by some body]The traditional Easterly Jet at 13 Degree Latitude over Chennai that usually prevails in monsoon period [July] was weak or not prominent; instead the stronger monsoon wind that emerged from Arabian Sea get advected and became higher level easterly divergent flow to form (neat Tibet) a high pressure area. This easterly winds played important role in late August to drag clouds from east to west. Thus there were unusual heavy rainfalls in North Coastal Tamilnadu i.e Cholamandalam Coast upto and along 10 Degree, South Coastal AP, Rayalaseema, western MP,Delhi,Rajstan,Gujarat. 


Posted by Kaneyen