A monster heat wave hit Karachi last month. High temperatures, absence of the normal cooling sea breeze, and a law that forbids eating and drinking during the month of fasting (Ramadan), turned the city into a veritable hellhole. As the death toll crossed 1300, hospital morgues ran out of refrigeration space and frequent power breakdowns made the stench of decaying corpses unbearable. The government, under harsh criticism for failing to react effectively, came up with a scapegoat: India. The minister for climate change, Senator Mushahidullah Khan, alleged that the coal-powered plants in Rajasthan, India, had sent hot air across the border!
Extreme weather is hitting Pakistan hard – very hard. If June was superhot, April was unseasonably cold in northern areas, where rain and hailstorms destroyed crops and fruit on a massive scale. All these pale before the abnormal events of 2010. Rains of biblical proportion followed a summer of extreme heat. Sheets of water poured from the skies for days leaving left two thousand dead, millions displaced, and 20% of Pakistan under water.
What did it? Some have begun to ask a different question: Who did it? There is rising temptation to put the onus upon some human agency. Hidden, malignant forces bent upon reshaping this country’s climatic pattern are being conjured up by many. Fringe academics in western countries, who claim that weather weapons are secretly being used by powerful states against weaker ones, are being quoted as authentic voices speaking for science.
A new book, “Reality of Floods in Pakistan” echoes the conspiratorial notion that India was responsible for the 2010 catastrophe. A chapter of the book is titled “The Broken Rhetoric of Pervez Hoodbhoy”!
Curiously enough, perhaps in the hope that my dissenting voice would draw a larger crowd, I was invited last month to be a speaker at the book’s launch in Islamabad by the author, Waqas Ahmed, a young Pakistani telecommunications engineer. Glowing tribute is paid on the book’s back cover by Pakistan’s famed nuclear scientist, Sultan Bashiruddin Mahmood. Mr. Mahmood, who also spoke, was given the national award sitara-e-imtiaz in 1998 for being the founder-director of the Kahuta Nuclear Enrichment Project that led to Pakistan’s acquisition of nuclear weapons. He is better known as Pakistan’s “jinn man” for advocating the capture of these fiery beings, who would then duly add their contributions to our electricity grid. He achieved additional recognition after meeting Osama bin Laden in Afghanistan in early 2001.
One argument in the book closely follows that of Pakistan’s famed chemistry professor, Dr. Atta-ur-Rahman (Fellow of the Royal Society), which he published in 2010. Therein the good professor, quoting political leaders and non-scientists rather than his own research in chemistry, alleged that the massive floods in July 2010, and possibly various recent earthquakes, were likely instigated by an experiment in Alaska called HAARP which directs radio waves at a part of the upper atmosphere called the ionosphere. My objections to this bizarre theory will not be repeated here. The interested reader can google the various subsequent public discussions on the topic.
Less bizarre, but no less wrong, is the book’s contention that seeding clouds can lead to catastrophic floods. I say this is less bizarre because diddling with the ionosphere cannot have the slightest impact upon weather but seeding clouds might have some. The book hints that five years ago India prepared some combination of drones, aircraft spewing chemicals, ground based cloud seeding generators, ionospheric heaters, and aerosol rockets that nearly drowned its unfriendly neighbor. But even if some of this paraphernalia could have been mustered without being detected, to cause massive country-wide rains is impossible. To understand this we first need to understand both the potentialities and limitations of cloud seeding.
For many decades we’ve known that spraying finely divided particles of certain substances, such as ordinary salt or sodium iodide, can coax the rain out of a cloud. But only sometimes! A cloud has to be of a particular kind with its temperature, density, droplet size, and internal wind currents being just right. Else seeding is useless, which is so about 80-90 percent of the time. Most importantly, you cannot alter weather over large areas with multiple clouds through this mechanism.
So what accounts for today’s extreme weather? Basically there are two culprits. First, plain bad luck – these things just happen! From heat and cold waves to tornadoes and typhoons, nature has turned extreme from time to time over hundreds of centuries. Even today, although we know a lot about jet streams and currents, specific occurrences can be foretold only a little in advance.
Talking of luck (or chance) cries for explanation. Yes, for all its precision, science actually needs this concept! Chance (probability) is a perfectly well defined mathematical quantity and essential because most systems are not rigidly deterministic. In particular, the atmosphere-ocean system contains chaotic fluids obeying certain equations which suffer from what is famously called the “butterfly effect”.
The butterfly effect is a metaphor for the particularities of a hurricane (strength, path, place of formation) being influenced by minor disturbances. Even a butterfly that flapped its wings several weeks earlier in China can make a difference! Before its discovery 50-60 years ago, it was thought that if atmospheric conditions could somehow be known exactly today, with big enough computers we could precisely predict weather for all times to come. But, as mentioned, weather equations are supersensitive to even the tiniest of input variations. This limits our ability for long-term prediction or for controlling individual events. Chance becomes inevitable. On the other hand, short term forecasts and weather averages are accurately predicted.
The second culprit is global warming. Greenhouse gas emissions from cars and factories have made Earth steadily warmer. Correspondingly, the atmosphere packs greater energy and more moisture. These lead to more and bigger storms, as well as extreme heat and cold events. But when or where an extreme event will hit cannot be predicted, much less controlled.
In a world crackling with multiple tensions, pseudoscientific allegations of weather modification can do great harm by increasing mistrust. Although one cannot vouch for the future, no country today is capable of using weather as a weapon. As increasingly severe storms, droughts, and wildfires in the United States demonstrate, even the world’s most powerful country – one alleged to be at the forefront of weather modification – has not escaped nature’s wrath. Humans have collectively made Earth sicker and more feverish, and now it is lashing back. Rather than lend our ears to conspiracy obsessed theorists, we need to cut down emissions and go for eco-friendly solutions for energy and urbanization problems. And, of course, cut down on population growth.
The author teaches physics in Lahore and Islamabad.