Six months of summer and less than two months of winter - this could be the new normal in the Northern Hemisphere by 2100 if effective climate change policies are not implemented.
The consequences on human health, as well as on agriculture and the environment, are inevitable.
This is demonstrated by a Chinese study led by the South China Sea Institute of Oceanology (SCSIO) and published in the journal Geophysical Research Letters.
The researchers, led by oceanographer Yuping Guan, compared the climatic data collected daily between 1952 and 2011, in order to verify how the rhythm with which the seasons alternate in the Northern hemisphere has changed.
This information was then fed into models that study climate change to simulate possible future scenarios.
The results of the study show that over 60 years the length of summer has lengthened from an average of 78 days to 95, while winter has shortened from 76 to 73 days.
The mid-seasons have also shrunk: spring has gone from 124 to 115 days on average, while autumn has contracted from 87 to 82 days.
The numbers also confirm that spring and summer start earlier than in the past, while autumn and winter start later.
The Mediterranean region and that of the Tibetan plateau are those in which the cycle of the seasons is most altered.
Unless this trend is reversed with effective climate change mitigation policies, it is possible that by 2100 summer will last six months, winter less than two, while spring and autumn will shorten further.
This will be able to phase out the biorhythms of plants, insects and animals, altering entire ecological communities and impoverishing agriculture.
Human health problems could also increase, with an increase in the duration of pollen allergies and a greater spread of disease-carrying insects.
