Study pitches for city-wise thresholds of temperature
NEW DELHI: A first-of-its-kind study, which measured the summer temperatures at which death rates increase, made a strong pitch for city-wise temperature thresholds to develop customized warning systems for all cities in the country. The research, carried out in Bhubaneswar, demonstrated how ambient temperature can kill due to all causes of mortality; not only those restricted to heat-related deaths.
The study was carried out by a team from the Public Health Foundation of India, the School of Public Health, the Kalinga Institute of Industrial Technology, the Bhubaneshwar centre of the Indian Council of Medical Research and the University of Nottingham in the UK found. It found that the killing effect of ambient heat starts to “kick in” when the maximum temperature crosses 36.2°C, but the major escalation occurs when it soars beyond 40.5°C.
The analysis is based on the rise in temperatures and death rates between 2007 and 2014.
The results could impact the policies of the Indian Meteorological Department and the National Disaster Management Authority. Both focus on temperature thresholds. “Apart from developing temperature mortality thresholds for different cities, we have also suggested using the traffic-light-like graded method in heat warning advisories,” said Ambrish Dutta of PHFI and the lead author.
Lipika Nanda of the PHFI, a co-author on the study, who is also member of the NDMA task force for heat wave preparedness, said the authority has already decided to urge states to get city-specific temperature thresholds assessed through its heat wave preparedness guidelines, which are to be issued next week.
Findings of the study
People die at a higher rate on hotter days than on relatively cooler days in the summer — the “hot days” are measured by the maximum day time temperature
“Hot days” that have hot nights, measured by the minimum temperature, are most risky
Meteorological system of the Indian cities should consider city-wise temperature “thresholds” that is at what temperature the fatal effects of ambient heat “kicks in”, as they vary from region to region, city to city
A fatal temperature for one region may be normal for other. For instance, heat tolerance threshold for a citizen in Bhubaneshwar will be different from the one in Nagpur
System should also consider “multiple thresholds” as this study was generated to set up a traffic
light of warning systems