Residents of Mexico City take shelter from the heat in a covered area, on a central street in the capital, in the month of March, when spring has not even arrived yet in the country. Heat waves will become more frequent and will last longer, due to the climate emergency. CREDIT: Emilio Godoy/IPS
By Emilio Godoy
MEXICO CITY, Mar 14 2023 – On Mar. 9, more than half of Mexico reported maximum temperatures above 30 degrees Celsius, although spring has not even arrived yet in this Latin American country located in the northern hemisphere.
In fact, the Megalopolis Environmental Commission, which brings together the federal government, the Mexican capital city government and those of five states in the center of the country, forecasts four heat waves, a level similar to that of 2022 – one in March, one in April and two in May – before summer.
Despite constituting a public health problem, Mexico lacks a national heat warning system, like the ones that other Latin American nations, such as Argentina, Brazil, Chile and Colombia, have in place.“The authorities must keep the public informed and get them to take the necessary measures. It is very important for the entire population to know what kind of weather lies ahead and to act appropriately. Unfortunately, misinformation is a social problem that we must eradicate all together, but it cannot be a pretext to say that we did not know what could happen.” — Ismael Marcelo
Ismael Marcelo of the National Meteorological Service recommended the creation of a warning system with a regional scope, based on temperature levels.
“Most of the population has a cell phone,” the meteorologist told IPS. “It’s important for the authorities to inform the public about meteorological events that affect us. In a culture of prevention, we have to adapt. At the National Meteorological Service we have all the tools to inform people, a website and through the social networks.”
A heat wave is an unusually hot, dry or humid period that begins and ends abruptly, lasting at least two to three days, with a discernible impact on humans and ecosystems, as defined by the Pan American Health Organization (PAHO), based in Washington DC.
These phenomena cause public health problems, especially for vulnerable groups – such as children and the elderly – food spoilage, increased air pollution, atmospheric environmental emergencies and forest fires.
The Geneva-based World Meteorological Organization warns that heat waves and other negative trends in the climate will become more frequent and will continue until at least 2060, due to the climate crisis.
In Mexico, a federal country, there are two governments that do have their own heat warning systems: Mexico City, which has a Meteorological Early Warning Network, and the southeastern state of Veracruz, which has a Grey Alert.
The scorching sun
Meanwhile, several Latin American countries do have heat warning systems.
In Colombia, a country of 52 million people, the government Institute of Hydrology, Meteorology and Environmental Studies monitors hot spots.
Lídice Álvarez, an academic in the nursing program at the Colombian University of Magdalena, told IPS about the relative usefulness of early warnings.
“In assessing how to prevent mortality from climatic events, we found that early warnings help, but it is difficult to predict certain events, because climatic variability further complicates things,” she told IPS from the city of Santa Marta, on Colombia’s Caribbean coast.
“What they do is to say that we are in a heat wave. But the public do not pay attention to the warnings. There is no discipline when it comes to checking climatological variables.”
In Colombia, heat waves have not yet occurred this quarter, but when the El Niño/Southern Oscillation (ENSO) phenomenon hits in July, a period of drought and lack of rain is expected, which will bring heat waves in the Caribbean zone in the second half of the year. ENSO cools the surface of the ocean and unleashes droughts in some parts of the planet and storms in others.
In Chile, a country of 19.2 million inhabitants, the government of Santiago introduced an “Extreme Heat and High Temperatures” system in December, which seeks to prevent deaths and protect people’s health during the southern hemisphere summer, through preventive alerts.
The number of heat waves in the Andean country increased from nine to 62 in the last 10 summers, according to figures from the Annual Environment Report from the government’s National Institute of Statistics.
In the metropolitan region there were 81 heat waves between 2011 and 2020 and forecasts point to a doubling of the percentage of days of extreme temperatures in the next 30 years. During a summer day in Chile, 100 people die from different causes, but when the temperature exceeds 34 degrees Celsius, the number goes up by 10 additional deaths, related to heat waves in Santiago.
Since 2018, Argentina’s National Meteorological Service (SMN) has operated a national warning system, which ranges from white to red according to the impact on human health, in the country of 46 million people.
Since 2009, the SMN has used a heat wave alert mechanism in the capital, Buenos Aires, which was later replicated in several other cities. In the current southern hemisphere summer that officially ends on Mar. 20, there have been nine heat waves so far, and in the metropolitan area of Buenos Aires a red alert has been issued due to the high temperatures.
The places marked in red show spots where temperatures above 30 degrees Celsius were recorded in Mexico on Mar. 9, according to a map of the National Water Commission. In Latin America, extreme heat warnings can save lives. CREDIT: Conagua
A worsening problem
In Mexico, population 129 million, events due to high temperatures and victims of heat stroke are on the rise, with the exception of 2020, due to the fact that the COVID-19 pandemic led millions of people to stay at home.
In 2018, 631 health incidents linked to extreme temperatures and 30 deaths were documented, with the numbers growing to 838 and 44 the following year, according to figures from the General Directorate of Epidemiology, under the Ministry of Health.
Due to the pandemic, the numbers fell to 193 health events and 37 deaths in 2020, but the first figure jumped to 870 in 2021, although the latter dropped to 33. However, in 2022 both statistics climbed, to 1,100 and 42, respectively.
PAHO recommends strengthening the ability of the health sector, through the design of action plans against heat waves that include improvements in preparedness and response to this threat, to reduce the excess of diseases, deaths and social disruptions.
It also recommends improving the capacities of the meteorological services to generate accurate projections and forecasts, so that meteorological information can be used for decision-making before, during and after a heat wave.
Marcelo, the Mexican meteorologist, emphasized the importance of disseminating information.
“The authorities must keep the public informed and get them to take the necessary measures. It is very important for the entire population to know what kind of weather lies ahead and to act appropriately. Unfortunately, misinformation is a social problem that we must eradicate all together, but it cannot be a pretext to say that we did not know what could happen,” he said.
Álvarez from Colombia said mortality is preventable. “We have focused on how people are part of the problem and can take measures. They believe that they cannot make any changes, but they are realizing that simple steps taken at home can generate changes,” she said.