It seems that climate on Indian subcontinent is changing its conventional trend. is this change caused by increasing pollution level or global climate change ?
In the past two years, global warming has only had an indirect effect on the rainfall and monsoon of India.
There have been two other very important factors that have created rainfall changes that are still relatively unknown by climatologists: 1.) The Pakistan-Arabia Dust Cloud, that has been the cause of droughts and floods, and I have a lot of articles about my research on the Dust Cloud attached to my Research Gate publications page that you can download, and
2.) Lack of Pseudomonas host plants. India has unfortunately chopped down 99% of their Pseudomonas tropical forest host trees, so when monsoon moisture travels over parts of India and you are expecting rain but get drought instead, because the Pseudomonas bacteria is no longer available to form rain clouds in those areas.
This is what happened in Pakistan about 3,300 years to the Indus Valley civilization, when to fire the millions of bricks to build their 1,000 cities, they chopped down all of the Pseudomonas tropical forest hoist trees to fire all those bricks and the monsoon rains stopped and their civilization failed.
This is a real possibility for all of India in the future, if the Pakistan-Arabia Dust Cloud keeps strengthening and not managed, and if the Pseudomonas host trees are not replanted and protected across India. These Pseudomonas host tree species need to be identified and protected as sacred trees or sacred forests, whose existence helps keep the billion+ people alive in India each year.
To date the Indian Monsoon appears to have been more strongly influenced by interannual and decadal variability than greenhouse gas induced climate change.
For example there may be a link with Atlantic multidecadal variability, and El Nino events induce a decrease in monsoon rainfall while La Nina events increase monsoon rainfall on average. This all helps to generate year to year variations of 10% or so in monsoon seasonal rainfall totals.
According to most climate models, increasing greenhouse gases are expected to increase monsoon rainfall. The projected increase over the next century is comparable to the year to year variability and is perhaps 10% - an amount which already has big impacts on year to year timescales. The following paper may be of interest but there are many others - see the work of Andy Turner at Reading University for example.
Based on the daily images of the Pakistan-Arabia Dust Cloud at http://www.nrlmry.navy.mil/shared-bin/display_image.cgi?URL=/aerosol_web/globaer/ops_01/india/current.gif
I am predicting this year that India and Pakistan will have a severe drought, except for floods on the western leading edge of the cloud, or if pockets form in the eastern edge and trap moisture.
Is there any money from your institution or from the Indian government to start tracking the daily position of the Dust Cloud and plot its effects on the monsoon in terms of droughts and floods?
California is in the middle of the worst drought in 1,000 years, and unless India starts watching the Dust Cloud;s daily impact on your monsoon and investing in curing it, India may blindly join Californians in having their own civilization-ending drought also? Once you study the daily movements of your Dust Cloud, you then have the tool to end floods and droughts in India and Pakistan, and start to have normal rainfall each month across both countries.
It is a difficult question to answer, but you want to minimize suffering by irregularities in the monsoon season. Since re-planting trees will take time (once and if it starts) you may take advantage of the Dust Cloud.
Half a world away, we had some rains recently in Canada as a result of dust from forest fires. It happened when the humidity happened to be high (more than 80%). If it was less than 50 %, probably no rain.
I noticed India had relatively high humidity before the monsoon rains came in. Since making rain is used in some places (China), it would be possible to induce precipitation from the Dust Cloud and/or a high humidity situation.
The Dust Cloud keeps rain clouds from forming, and has the opposite effect than other aerosols that help rain cloud formation.. You can see the impact of the Dust Cloud in keeping the potential cyclone that was forming in the Arabian Sea last week from raining on Pakistan and causing a heat wave instead, at http://rammb.cira.colostate.edu/products/tc_realtime/archive.asp?product=16kmgwvp&storm_identifier=IO972015. Image from June 22 attached
The main monsoon circulation in the world (Indian, African, American) is the processes that formed the planetary processes of circulation of the atmosphere and the oceans. Of course they are bound to global changes in the natural world. We found that from 2008 to 2009 under the influence of certain geophysical parameters rainfall across India decreased.