Ice melting, flash floods, salt in aquifers, desertification. 2016 was the hottest year since 1880. With a possible domino effect in the future
“We have seen such extraordinarily extreme weather patterns. If you consider the vastness of this universe, planet Earth is just a small boat: if this boat is sinking then I think that we will all have to sink together.” With these words Ban Ki-moon, former Secretary General of the United Nations, welcomed Leonardo Di Caprio to the UN headquarters in New York. The actor, a long-term advocate of environmental issues, was filming his documentary Before the Flood with a very clear objective: to demonstrate to the general public that global warming is real threat and not, as America’s new president Donald Trump thinks, “created by and for the Chinese to make US manufacturing non-competitive.”
News about global warming continues to mount up each day. The latest update has arrived from the US Federal Agency, the National Oceanic and Atmospheric Administration (NOAA) with the announcement that 2016 was the hottest year since records began in 1880. A NASA video demonstrates unequivocally how since 1880 average temperature has increased by +1.1°C, “a change,” the US space agency explain, “that is largely due to the increase in the atmosphere of CO2 and other man made emissions.”
The high in 2016, however, is no fluke seeing as the last three years have been the warmest on record, a trend that, according to Hans Joachim Schnellnhuber of the Potsdam Institute for Climate Impact Research, brings with it dramatic consequences. First among these is the shrinking of the Arctic and Antarctic ice caps, which in 2016 reached their smallest size since 1979, the year in which their surface was first measured. The melting of the polar ice together with the expanding volume of the oceans (which further increases the ocean temperatures) leads to rising sea levels, which in turn causes flooding and coastal erosion. In the Annual Global Climate and Catastrophe Report the insurance multinational AON underlines how in 2016 natural disasters caused directly by climate change have caused an estimated 30 billion dollars of damage, the highest figure for the last 16 years, concluding that “in the near future the losses linked to climate catastrophe will increase.” This is a genuine problem for insurers that are finding themselves in increasing difficulty managing the growing number of extreme events linked to climate change.
According to analysis by ClimateWise, a global network of 29 large global insurance industry organisations convened by the University of Cambridge Institute for Sustainability Leadership, “Since the 1950s, the frequency of weather-related catastrophes, such as windstorms and floods, has increased six-fold. As climate-related risks occur more often and predictably, previously insurable assets are becoming uninsurable, or those already underinsured further compromised.”
Italy is by no means immune from the effects of climate change. Studying the phenomenon are the non-profit associations (such as Rete Clima), individual scientists (such as climatologist Antonello Pasini, who writes an eagerly followed blog in Le Scienze), universities (in the academic year 2016/2017 the University of Pisa, established the country’s first degree course in Climatology) and research organizations financed by the state such as the Centro Euro-Mediterraneo sui Cambiamenti Climatici (CMCC), founded in 2005. Through the studies that the CMCC has carried out on the interactions of the environmental system with society, it is possible to comprehend the extent to which the consequences of global warming are already having a notable impact in Italy. The list of consequences represents a long chain of connected events, a sort of dramatic domino effect that also includes some less predictable twists. It begins with the temperature, which is increasing globally and has led to a rise in the number of wildfires in Italy and the need for cities to manage the summer heat waves that each year are lethal for thousands of elderly people: often the only solution is to invite the population to seek refuge from the heat for a few hours in the air-conditioned shopping centres.
Connected to the increase in temperatures is the so-called ‘tropicalization’ of the climate in temperate areas: in short, it rains less but it rains more violently, even in Italy. The flash floods can arrive with an intensity ten times greater than normal rain and the damaging effects of these extreme phenomena are numerous: roads, bridges, underground transport and sewerage systems are put under considerable stress, the man made river channels often cannot contain the violent and sudden flows of an enormous volume of water and the number of landslides caused by the weather are increasing disproportionately. The whole water system is threatened, already unstable and exhausted by months of drought and worsened by unregulated activities and poor maintenance. Further complicating the situation is the increase in recent years of tornados and ‘Medicanes’ (a portmanteau of Mediterranean and hurricanes), cyclones that have been hitting the Mediterranean Sea with an intensity that is more often associated with tropical climates.
Unfortunately it does not end here. The rising sea levels are damaging the coastal ecosystems and threatening the port cities (there is an attempt to protect the Venice lagoon with a huge engineering project called MOSE). The rising sea levels together with other factors contribute also to coastal erosion and the increase in saltwater intrusion, the presence of seawater in the final stretches of rivers.
Fifty years ago in the Po delta the sea water intrusion reached no further than three kilometres inland, today the phenomenon has been detected twenty km from the sea: a worrying phenomenon that increases the salinity of the water table, makes the ecosystem more arid and denies fresh water to agricultural activities. Erosion, saline intrusion, falls in average rainfall and temperature increases are factors that contribute, also in Italy to the loss of cultivatable land. Agricultural association Coldiretti, quoting data from Ispra, claims “since the seventies the available farmland in Italy has been reduced by 28%.” The risk of desertification is particularly high in the southern regions, in particular Sicily, Puglia and Basilicata, where agriculture too is changing: they have been forced to bring back long-lost varieties of crops that require less water and are more resistant to drought, while the cultivation of fruits, cereals and vines is shifting ever northwards. “In Southern Europe,” explains the European Environmental Agency, “extreme heat waves and the reduction in rainfall and available water have had a negative influence on agricultural productivity. Forecasts predict that agricultural production will become increasingly variable each year, caused by extreme weather and other factors such as the spread of parasites and diseases”.
All in all global warming is having a slow but progressive impact on the entire human ecosystem, on our culture, our habits and our lives. As Barack Obama explained to the New York Times, “What makes climate change difficult is that it is not an instantaneous catastrophic event. It’s a slow-moving issue that, on a day-to-day basis, people don’t experience and don’t see but it is the greatest long-term threat facing the world.”