Subscribe
A new study has predicted a 68 per cent chance of temperatures and humidity levels smashing records in India and other tropical countries this summer.
Northern India, for example, faces a 50 per cent chance of suffering record heat and humidity this summer, the study published in the journal Geophysical Research Letters stated.
The new research established the potential to predict the maximum wet-bulb temperature of a particular year five months in advance, the authors claimed.
Wet-bulb temperatures are calculated using data on air temperature and humidity. It measures how well our bodies cool down by sweating during hot and humid conditions. In warm-humid environments, wet bulb temperatures above 30°C could lead to irreversible heat stress. Further, it is also predicted that extreme wet bulb temperatures in the tropics could rise by 1°C for every 1°C increase in tropical mean warming.
Though weather models are good at providing short-term predictions, they are bad at doing the same several weeks in advance. The researchers explained that such long-term predictions can help regions prepare for extreme heat events and protect humans, livestock and crops.
“Humanitarian aid and outreach, preparation for medical care and advising and distribution of crops and agricultural equipment can all be adjusted in ways that can account for that prediction," William Boos, professor of earth and planetary science, University of California Berkeley and author of the study, said in a statement.
They arrived at this after considering the strong‐to‐very‐strong El Nino at the end of 2023 and its impact on tropical heat and humidity.
El Nino is the warm phase of a recurring climate pattern across the tropical Pacific — the El Nino-Southern Oscillation (ENSO). El Nino pumps heat and moist air into the upper atmosphere that spreads around Earth’s equator.
They compared this with data on heat and humidity extremes throughout the tropics over the last 45 years. They then combined the data with the increased temperature and humidity accompanying global warming. The continual rise in global average temperature compounds the impacts of El Nino, Boos said.
Their analysis showed that the ‘strong‐to‐very‐strong El Nino’ at the end of 2023 suggests the tropics could likely experience a mean daily maximum wet‐bulb temperatures of around 26.2°C, with a 68 per cent chance that these regions could shatter existing records in 2024.
The five-month lead time for the prediction is based on the current state of ENSO. “If weather centres could forecast ENSO conditions six to 12 months in advance, the lead time for wet bulb temperature predictions could be extended to approximately a year, allowing even more preparation time for societies across the tropics,” Yi Zhang, postdoctoral fellow, department of earth and planetary science, University of California, said in a statement.
An April 2024 advisory from the United States National Oceanic and Atmospheric Administration predicted a transition from El Nino to ENSO-neutral by April-June 2024, with an 85 per cent chance. The odds of La Nina (the cool phase of ENSO) developing was likely in June-August 2024, with a 60 per cent likelihood.