We can no longer ignore the emerging reality of climate change. Disastrous rains in Karachi have proved beyond any shadow of doubt that climate change is now a stark and dreadful reality for Pakistan. And the sooner we wake up to the threat and take it seriously, the better for our future generations.

The global atmosphere is changing fast as manifested in sudden alterations in the climate cycle for various countries. These alterations stem from large-scale deforestation, increased use of fossil fuels, and other toxic commercial and industrial activities. In terms of climate change, Pakistan is a high-risk country. The Global Climate Risk Index 2019 by Germanwatch ranked Pakistan as the 8th most affected country when it comes to extreme weather events. The report noted: “Countries like Pakistan that are recurrently affected by catastrophes continuously rank among the most affected countries both in the long-term index and in the index for the respective year”. In the same report, India is placed at the 14th position in terms of the impact of extreme weather events.

According to an estimate, natural disasters claim around 90,000 lives and affect more than 150 million around the world every year. Among these, floods pose the greatest threat to lives and livelihoods, inundating large swathes of land across borders. Figures quoted by authoritative sources show that between 1998 and 2017, floods affected nearly a third of the global population, or 2 billion people worldwide. Floods have long-term effects on a country’s economy. These include destruction of infrastructure, loss of means of livelihood and disastrous ecological changes which arrest the economy’s growth momentum.

A steep rise in the frequency and intensity of floods is the most devastating consequence of climate change. It is estimated that 80-90pc of all natural disasters in the past decades have, on average, been a result of floods, heat waves, droughts, and storms. Floods and extreme variations in precipitation are expected to contribute to flooding in areas that have historically remained immune to it. A recent report of the United Nations Economic and Social Commission for Asia and the Pacific on the risk of floods and droughts during the monsoon season said that over eight million people would be exposed to flood risk in Pakistan this year alone.

Agriculture in most countries in South Asia is dependent on monsoon rains in the months of June to September. Rains during these crucial months irrigate about 60pc of cultivated land in Pakistan and India. Failure of the monsoon or abnormal showers destroy standing crops. Over the past few years, there have been wide-ranging temporal and spatial variations in monsoon rainfall. The repetitive cycle of floods and drought means the loss of livelihood for millions of farmers dependent on nature’s bounty.

Pakistan was a victim of devastating floods in 2010, which destroyed the hearth and homes of over 20 million people. The loss computed in economic terms was around $10 billion. Floods in parts of Pakistan are now a recurrent annual phenomenon. But no long-term strategy has yet been developed to deal with the threat. Surely, the time has come to put in place an effective mechanism to deal with the growing menace of urban flooding.

We saw what happened in Karachi in the last fortnight. The devastating rain spell later spread to the north, inundating large tracts of land in Khyber Pakhtunkhwa and Gilgit-Baltistan. But Karachi was the hardest hit of all. The mega city’s administrative and operational infrastructure virtually collapsed under the weight of incessant rainfall. Besides the loss of over 50 lives, the city’s industry and businesses suffered loss of tens of billions of rupees, a conservative estimate according to knowledgeable circles.

Urban floods are caused by rapacious land use, haphazard and mindless urbanisation and proliferation of squatter colonies, alteration of natural watercourses, and inadequate drainage and sanitation infrastructure. Urban flooding hits, when rains exceed the capacity of an urban area’s drainage system.

Over the years, agricultural land and green pastures around our major cities have disappeared in the face of creeping urbanisation and illegal housing projects. Unplanned residential settlements, buildings, roads, and bridges come in the way of natural water flow channels. With the absorption capacity of the soil sapped over time, sudden cloudbursts result in uncontrolled flooding.

The situation is worsened by the obstruction of drainage systems and other pathways by solid waste causing flood water to spread all over. The accumulation of sediments and refuse in canals and waterways, and outdated and overburdened drainage and sanitation infrastructure, contribute to the kind of flood devastation we saw in Karachi. The problem calls for both micro and macro level solutions. Pakistan’s forest cover of around 4 percent is one of the lowest in the world. A billion tree plantation drive is the right step in addressing the issue.