KARACHI, Pakistan: It is more than five decades ago since Sabir Gul first arrived in Karachi from a small town in northwestern Pakistan but he still remembers the mild, cooling weather of the port city as he got off the bus to start a new life. That was in 1968, but since then Karachi has become one of the planet’s climate hotspots, according to the World Bank. In April, the city and financial hub of the country had its hottest day since 1947 when the mercury rose to 43.6 degrees Celsius. In June 2015, 1,500 people died due to heat stroke and dehydration during a heatwave. The Global Climate Risk Index 2020, issued by think tank Germanwatch, ranked Pakistan fifth on a list of countries most affected by planetary heating over the past two decades — even though the south Asian nation contributes only a fraction of global greenhouse gases. Gul reckons there is only one way to fight the raging climate war: By planting more trees and taking care of the ones that exist. In his quest to bring down temperatures in Karachi, the retired gardener has planted 4,000 trees in the city with the help of the former chairman of a union council and leader of the Al-Khidmat charity organization, Junaid Mukati. “I worked as a gardener for 23 years, but when I retired, I thought I should do something for the people of this city. Then Junaid Mukati came up with the idea of developing green localities, and I told him it was the best thing we could do,” Gul said. Together they planted thousands of trees. “Now I take care of them just like I take care of my children,” he added. Scientists point out that as trees grow, they help stop climate change by removing carbon dioxide from the air, storing carbon in the trees and soil, and releasing oxygen into the atmosphere. Trees also offer cooling shade in places such as Karachi, attract birds and wildlife, purify the air, prevent soil erosion, and clean water. But in the absence of a massive tree-planting drive, officials fear Karachi will only get hotter and more unlivable. “Karachi’s maximum daytime average temperature for the last 30 years is 32.51 degrees, and night-time minimum normal temperature is 21.67 degrees,” Pakistan’s Meteorological Department director, Sardar Sarfaraz, said. But between 1991 and 2020, Karachi’s day and night temperatures increased by 0.77 and 1.53 degrees, respectively, he added. “With this prevailing trend, it is statistically expected that Karachi’s day and night temperature may rise by 0.3 degrees to 0.5 degrees Celsius in the next 10 years,” Sarfaraz said, figures he described as “alarming and severe.” In 2018, Pakistani Prime Minister Imran Khan launched an ambitious five-year tree-planting program, the 10 Billion Tree Tsunami, to counter the rising temperatures, flooding, droughts, and other extreme weather in the country that scientists have linked to climate change. In June, the economic survey report said 350 million trees and 814.6 million plants were seeded in the country under the program. In Karachi too, the capital of Sindh province, the provincial government said it had conducted several plantation campaigns. City administrator Murtaza Wahab told Arab News that several urban forests would be created in the city. But more needed to be done, Gul said, and quickly. “Trees will benefit our coming generations. They are the best remedy against heat waves.”