Uncontrollable sneezing, red eyes and runny nose, the beginnings of spring often rhyme with the first pollens of the year. With global warming and rising temperatures, allergy season could start much earlier and end much later according to a recent study published in NatureCommunications.
If you live on the Mediterranean arc, you may have the nose itchy, the eyes runny and uncontrollable sneezing for a few days. In the region, the cupressaceae (redwoods, the cypress and junipers) come out of their winter rest and produce pollen in large quantities. In the west of France, it is ash pollen that saturates theair. The 2022 season started quite early, from mid-January, in particular because of the mild temperatures recorded at the start of the year. A trend that is likely to continue, or even increase, with the global warming.
The endless allergy season
Yingxao Zhang and Allison Steinerfrom Department of Climate and Space Sciences and Engineering from the University of Michigan, are working on a computer simulation which predicts the intensity and the duration from emissions daily pollen between 2081 and 2100 — in a world where temperatures would have jumped by 4 to 6°C. Their analysis concerns only the United States and 13 taxa of plants responsible for 77% of allergies respiratory systems in the country. According to their results, the season from pollen could be much longer, but also more intense than the one we are currently experiencing. Bad news for allergy sufferers!
The simulation indicates that spring pollens could appear 10 to 40 days in advance, and those of summer andfall last up to 15 additional days. Regarding the intensity of pollen emissions, all species botanicals analyzed here do not react in the same way. For example, the precipitation and temperature decrease daily pollen production by 33% for alder, but increase that of oak by 50%.
Even so, the overall increase in pollen emissions over one year is up 16 to 40%. Who says more CO2 atmospheric, also says more pollen. It’s a sighting made for many years by the scientific community. When the CO concentrations2 enter the researchers’ simulation, the peak in pollen production is 200% higher than that observed in recent years, still in the United States.
An important public health topic
Respiratory allergies due to pollen are a real public health issue. They concern 20 to 25% of French people, adults and children alike. In predisposed people, respiratory allergies, such as tobacco or pollution, can promote the appearance of asthma. This chronic disease is characterized byinflammation from bronchi which causes episodes of shortness of breath, dyspneaof pressure chest and cough.
Nearly 2,000 people die each year from the consequences ofasthma including a hundred children, adolescents or young adults. Public Health France estimates that more than 60,000 people are hospitalized for an asthma attack every year. In future years, respiratory allergies are likely to last longer and be more severe, increasing the risk of complications.
Interested in what you just read?