Thursday, November 8, 2012

Increased or reduced future rainfall for India? Global warmist can’t make up their minds!!!

The IPCC, in its 2007 report, predicted that global temperatures will rise by 2-4.5°C by the end of this century, with a 2.7-4.3°C increase over India by the 2080s. The panel also predicted an increase in rainfall over the Indian sub-continent by 15-20 percent and that the sea level would rise by 88 centimetres by 2100. 

There would be losers and winners in any climate change and if the IPCC model predictions are any yardstick to go by, then India had every reason to be more than happy with global warming as it would have brought increased rainfall that in turn would have boosted agricultural production and productivity in the country. 

But alas, none of these model predictions have todate actualized. In fact, Indian rainfall has been relatively stable, if anything, with a negative departure around one per cent from normal.

Now, climate alarmists have switched into reverse gears in their prediction, if the Potsdam Institute for Climate Impact Research, Germany research study is to be believed and published as a runup to the Global Climate Summit to be held at Qatar from Nov. 26-Dec. 7 this year.  Here are the salient points of the study:

- The study, in the journal Environmental Research Letters, projected a temperature rise of 4.6 degrees C (8.3 F) over pre-industrial times by 2200. UN scenarios indicate a gain of between 1.1 and 6.4 degrees C (2.9-11.5F) by 2100. 

-  Monsoon failure becomes much more frequent" as temperatures rise. The Indian monsoon is likely to fail more often in the next 200 years threatening food supplies, unless governments agree how to limit climate change

-  The monsoon rains could collapse about every fifth year between 2150 and 2200 with continued global warming, blamed mainly on human burning of fossil fuels, and related shifts in tropical air flows and the "failure" as a deficiency in rainfall would be between 40 and 70 percent below normal levels. Such a drastic decline has not happened any year in records dating back to 1870 by the India Meteorological Department, they said.

-  "In the past century the Indian monsoon has been very stable. It is already a catastrophe with 10 percent less rain than the average,"  

- The study projected a temperature rise of 4.6 degrees C (8.3 F) over pre-industrial times by 2200. UN scenarios indicate a gain of between 1.1 and 6.4 degrees C (2.9-11.5F) by 2100.

-  By modelling past data, the researchers found that there are two monsoon modes. In the first, spring sees the troposphere over land being warmer than that above the ocean. Moist air moves over the continent and the resulting rainfall releases latent heat. This reinforces the tropospheric temperature contrast, and stabilizes the air circulation, in what the team dubbed the wet moisture-advection feedback.

-  In dry years, in contrast, less humid air in the upper troposphere tends to sink over both land and the Arabian Sea. This suppresses rainfall and keeps sea-level pressure anomalously high throughout the summer. As a result, the direction of the monsoon flow in the upper troposphere tends to change from generally westward to northward or even eastward. In the same way that rainfall sustains a wet monsoon regime, the team believes this anomalous circulation pattern may be a self-amplifying feedback that can sustain a dry-monsoon regime – the "dry-subsidence" feedback.  

-  But the study said that the shifts would disrupt air flows known as the Pacific Walker circulation, which usually helps to drive the Indian monsoon by bringing high pressure to the western Indian Ocean. 

-  In years with an El Nino weather phenomenon, which warms waters in the eastern Pacific, the Walker pattern gets shifted eastwards, bringing high pressure over India. That pattern suppresses the monsoon. "As temperatures increase in the future, the Walker circulation, on average, brings more high pressure over India, even though the occurrence of El Nino doesn't increase," a statement about the findings said.

We question many of the assumptions of the study:

1. Are there evidences of accelerated global warming?

 One of the most cited global surface temperature dataset as used in climate science and treated as the gold standard of the IPCC is UK’s HADCRUT compiled by the Met Office’s Hadley Center and the now-disgraced Climatic Research Unit at the University of East Anglia — the institution at the centre of the infamous Climategate scandal that exposed so-called “climate scientists” fudging numbers, covering up contradictory data, conspiring to attack dissenting experts, and unlawfully trying to evade freedom of information requests. The data combines surface and sea temperatures. While the Hadley Centre is responsible for the sea surface temperatures, the CRU takes care of the land temperatures.
The latest report by HadCRUT published the above graph that admitted that there is no statistically significant global warming for past 16 years. By their own null hypothesis, if there is an absence of statistically warming for 15 years, then the global warming hypothesis stands falsified.

Now the HadCrut graph finds high correlation with the temperature graph of India as compiled by the Indian Meteorological Department (IMD) as quoted in the report titled ‘Climate Change and India: A 4X4 Assessment’, (2010) Ministry of Environment & Forest, India. Read here. 

While the mean warming for last century is 0.51 deg C; from 1940-1990 it was 0.20 deg C/100 years while from 1997 warming is flat at 0.09 deg c/per 10years. 

Observational data confirms that there is no evidence of accelerated warming as Potsdam Institute’s hysteria generation. In fact, all indications point to the fact that we have already entered into a global cooling cycle which will start accelerating from now on. 

Can Rainfall Decrease 40-70%?     

It is significant that the Potsdam Institute themselves accept their findings controversial and admit their model prediction of 40-70% has not occurred during recorded history, going back to 1870 and the rainfall till now has been stable.    

As seen from the above graph, Indian monsoon has been demonstrating a 30 year alternating cycle of excess-deficient rainfall periods. We have now entered the next 30 year cycle of excessive rainfall cycle. Rainfall by and large fluctuate within the +/- 20% range.  

It is interesting that Potsdam Institute predict “monsoon rains could collapse about every fifth year between 2150 and 2200” and not in our life time. How many of us will be around in 2150 or 2200 to ensure their prediction had been accurate.  

And yet, in one of the IPCC reports viz AR3 2001, they however admitted: 
 “The climate system is a coupled non-linear chaotic system, and therefore the long-term prediction of future climate states is not possible.” 
It follows that the IPCC's models are not falsifiable and thereby are not scientific models. What the IPCC reports provide in lieu of "predictions" are computer simulated "projections" based on several assumed scenarios. 

It must be appreciated that the Potsdam Institute’s prediction are not predictions but model projections. The difference between the two terminologies is as follows:    
- a projection is a mathematical function that maps the time to the computed global average temperature;
- a prediction is a proposition that states the outcome of a statistical event.   

According to Popperian principles, a theory is only scientific if it is falsifiable. Popper additionally argues that though we cannot prove that a theory is true, we can certainly show that a prediction is false. A prediction can be tested to discover it is not true by using the logical concept - ‘modus tolens’ to either validate or refute the theory:  

If the theory is true, then the prediction is true
The prediction is not true.
Therefore, the theory is not true.  
It follows that Potsdam Institute's hypothesis and consequently models are not falsifiable and thereby are not scientific models as they are projections not predictions.
Now even if we were to treat Potsdam Institute’s projections as predictions, why did all the international models went awry predicting this year’s South West Monsoon? If we were to take Potsdam Institute seriously then they should have good track record in predicting Indian monsoons. They have none.  Even our IMD is far better than them. And we are expected to sheepishly believe the Potsdam Institute’s 150-200 years predictions, when none us, including our children would be alive to verify it is true.

The difference between climate and weather is that climate is average weather over a long period, now usually considered as 30 years. If a model is unable to predict the current season’s monsoon, only the naive would treat their 150-200 years projection as gospel truth. Consider this in concluding, the IMD a few days admitted that they had no models to predict the North East Monsoon!

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