HT spotlight: Chandigarh growing hotter by the decade
Urban heat island effect due to rapid urbanisation and the growing traffic is leading to the rise in temperature in the city; extreme winter conditions have shifted from November and December to January and the monsoon pattern has also changed, affecting the cropping routineUpdated: Mar 28, 2019 22:07 IST
Chandigarh is growing warmer since it came up in the ’50s. The winter isn’t as cold and the summer stretches longer. The India Meteorological Department (IMD) says the average minimum temperature of the city has gone up by 1.78 degrees Celsius, while the maximum temperature has gone up by 0.63 degrees Celsius over the past seven decades.
The IMD data shows an increase in the average minimum and maximum temperatures from 1950-80 and from 1970 to 2010 for every month. The increase has been the most in February.
ML Sarin, 70, who has been staying in Chandigarh for 64 years, says, “Due to global warming, there has been an increase in the temperature across the country. Dust storms were common in Chandigarh. With the growing construction, strong winds have subsided and could be one of the reasons why the city has become warmer.”
Swadesh Talwar, 74, who has seen the city grow over 52 years, says the weather has become unpredictable now. “This year, the winter rain went on longer. Earlier, rain would stop by Basant Panchami that heralded the advent of spring. But now we are heading straight into summer. During the last two years, winter was shorter than normal. Seasons are turning topsy-turvy,” he says.
In 1982, the furthest year for which his data is available with IMD, Chandigarh, the highest maximum temperature of the year was 43.5 degrees Celsius in July, while the lowest minimum temperature was at 4 degrees Celsius. In 2018, the highest maximum temperature was 43.6 degrees Celsius in May, while the lowest minimum temperature was 3.2 degrees Celsius in January.
The impact and solution
Shivinder Singh, a scientist at IMD, says temperature variations from global warming can be observed by studying data on a decadal scale but a similar study must be carried out for the entire region to determine if it is, in fact, the result of climate change.
Local IMD director Surender Paul says the urban heat island effect is the main reason behind Chandigarh growing warmer. “In the 1950s, the city was barely constructed. As it became urbanised, green cover was reduced. Roads made of tar acted as heat wells were built along with tall buildings. Chandigarh saw rapid development in a few decades which is why the temperature variation is noticeable. Climate change has been working in the background over the years.”
Suman Mor, an assistant professor at the department of environmental sciences at Panjab University, says even a little increase in temperature can impact people in different ways.
“Crop production has been hit the worst. Being agrarian economies, this has affected Punjab and Haryana. The period of extreme winter has shifted from November and December to January over the years, and the pattern of monsoons has changed due to which
the dates for sowing and harvest have got affected.”
She says waste segregation is the need of the hour as landfills have been shown to release methane and carbon dioxide over time when waste is not segregated.
Green energy and cover
Chandigarh administration director, environment, Debendra Dalai says besides the increase in population and number of vehicles, emission of greenhouse gases has increased over the decades.
“It’s important to switch to sustainable sources of energy and also to increase the city’s green cover. We plan to plant 2.5 lakh saplings in the city by this year-ed. We are encouraging more sustainable means of transportation such as bike sharing and e-buses to tackle emissions.”
Chandigarh is only a micro-climate zone and a holistic approach needs to be adopted at the regional level for a significant impact on controlling the rising temperature, he says.
This year, the temperature has been on the lower side, pointing towards the variability of the climate.
With 18 western disturbances this season, February was the coldest in five years, while January was the warmest in four years.
Traffic, a red zone
The trend of rise in temperature can also be attributed to the increase in the number of motor vehicles in the city. Regional Licensing Authority (RLA) records show 11.6 lakh vehicles have been registered in Chandigarh, while there were only 23,224 vehicles registered in the city in 1974. In 44 years, the number of cars has grown 50 times. The increase in the number of vehicles has led to the release of more toxic fumes into the environment.
The city’s population has also grown but not as exponentially as the number of vehicles. There were 3.15 lakh people in the city in 1974 and the population grew to 11.2 lakh in 2018. As compared to the 50-time jump in the number of vehicles, the population growth is only 3.5 times during the same period. The increasing population is also a reason for the rise in temperature.
Farming is also attributed as one of the sources for methane and carbon dioxide being released into the environment, both of which are green-house gases.
First Published: Mar 28, 2019 16:34 IST