2010 Pakistan Floods: Climate Change Or Natural Variability?” by Madhav L Khandekar

I have been alerted to an excellent article by Madhav L. Khandekar from the latest edition of the CMOS Bulletion.  The article is titled

2010 Pakistan Floods: Climate Change Or Natural Variability?”  [this article was also posted on ICECAP]

The article starts with the text

“Among the extreme weather events of summer 2010, the extensive floods in Pakistan and their widespread impacts garnered maximum attention in the media as well as in the scientific community. Several climate scientists expressed concern about such weather extremes becoming more common with future climate change, while the WMO (World Meteorological Organization) issued a statement that theThe extensive weather related cataclysms of July and August ( 2010) fit patterns predicted by climate scientists. Damage due to floods and plight of thousands of people marooned over waterlogged areas were graphically covered in heart-wrenching details by most newspapers and TV news stories in Canada. Per latest estimates, the floods have claimed over 1500 human fatalities so far and over two million more have been rendered homeless. From a personal perspective, the TV footage of women & children in knee-deep water brought back poignant memories of a similar situation I witnessed in Pune, my former home-town (a city 200 km southeast of Mumbai, the largest Indian city on the west coast) in July 1961 when incessant monsoon rains in the first week of July 1961 led to the breaking of a dam resulting in massive flooding of the city, destroying hundreds of homes and drowning dozens of people living along the riverside. Several other cities and regions suffered from similar flooding during the 1961 summer monsoon. As it turned out, the 1961 summer monsoon over India and vicinity was the rainiest monsoon season in the 150-year instrument data which caused extensive flooding and loss of life and property in many regions of the country (India Meteorological Department 1962). This year’s monsoon has been quite vigorous since the third week of July 2010 and heavy rains have caused flooding in the peninsular regions of India and also in the northwest regions bordering with Pakistan. Has the vigorous Indian monsoon of 2010 led to the historic floods in Pakistan? Let us briefly consider the monsoon climatology.”

His conclusion includes the text

“A rapid transition of the ENSO phase from El Niño to La Niña between spring and summer of 2010 appears to be the key element in triggering a vigorous monsoon of 2010 over the Indian subcontinent…….the 2010 Pakistan floods, although seemingly unprecedented, were well within natural variability of monsoonal climate over the Indian subcontinent.”

Read the full article here.

Madhav sent me the e-mail below also when I alerted him that I was posting on his new article

Dear Roger

I look forward to seeing my article on your webblog.

May I suggest, you also want to post my earlier article ” the notoriously unpredictable monsoon” along with the latest one? You did post it a few months ago.

This may enable readers of your blog to realize how Indian ( and possibly south Asian) monsoon which was about 25% below average last summer ( 2009) is about 5% above normal this ( 2010) summer, a dramatic flip from ‘drought’ to ‘flood’ in just one year!

This means that just in one year, the total land-based rains increased by about 30% ( of normal value of about 890 cm). This translates to about 25 cm of rains over the entire land-area of India, about 3.3 million sq km! This represents a huge increase in amount of water falling, from last summer to this summer in four summer months and cannot be fully explained by a simple “global warming & increased atmospheric moisture” hypothesis.

For ready reference, [here is] the PDF of my earlier article which appeared in CMOS Bulletin December 2009.

Regards

Madhav

Khandekar, M., 2009: The Notoriously Unpredictable Monsoon, CMOS Bulletin SCMO Vol.37, No.6