IPCC 2018 report: a call for teamwork
These days TV newscasts worldwide are recounting about the raging flames that are igniting the state of California where more than 6,700 structures have been destroyed and more than 200,000 acres were burnt. The current fire, that has killed 42 civilians and reported 228 missing, is already the deadliest and most destructive in California’s history, and the damages continue, as the blazes show no signs of ending. President Trump has blamed the wildfires, unfortunately very recurring in the Golden State, on the “forest mismanagement”, moving a heavy attack against the Democratic administration of California. On the other hand, the current State Governor Jerry Brown responded by stating that the management of the forest could in no way stop climate change, suggesting the latter, and those who deny it, as the main contributors of the catastrophe. Global warming is also said to influence the formation of Atlantic Hurricanes. According to some studies, the increase in temperatures would allow hurricanes to absorb more energy and thus be more powerful. Also warmer oceans’ waters make the speed at which hurricanes intensify in strengthfaster than before. In particular, meteorologists use the term “rapid intensification” (or “RI”) to describe a storm that increases its maximum sustained winds by at least 35mph within a 24-hour period.The next chart, from the National Hurricane Center, shows that the number of RI hurricanes is definitely increased through the last decade, peaking in 2017, even if storm activity for 2018 is expected to be a “below-normal”, according to the National Oceanic and Atmospheric Administration (NOAA).
The experience of more extreme weather phenomena has concerned the European Continent too, as in mid-October Portugal and Spain were touched by the tropical storm Leslie, right after it’s status was declassed from “Category 1 hurricane”. Reportedly, Leslie was the strongest storm to hit Portugal in a long period of time, in term of wind speed and rainfalls, and followed in the footsteps of Ophelia, that made landfall in Ireland in the same period one year before, recording the fastest winds ever experienced in the country.Italy has been hit recently by severe weather conditions too, as multiple rainstorms have caused onerous damages to numerous regions of the boot, restituting destruction images that millennials have never seen before.Winds and heavy rainfalls destroyed portions of forests in the North-Est and left several small towns without the principal utilities, and coastal storms have annihilated holiday resorts, their harbors and waterside routes. Moreover, especially in the south, fields were completely covered in few hours by the intense rain, causing pricey economic damages to the agricultural industry of the areas. Some inhabitants are sure that various locations will never look the same in the future.
The spreading of severe weather conditions has again raised the attention over the issue of global warming. The majority of the scientific studies over the topic are convinced that the current increase of 1°C in the average temperature worldwide, with respect to the pre-industrial situation, have contributed to the extreme level reached by atmospheric phenomena. But some research entities, such as the Geophysical Fluid Dynamics Laboratory (Sept. 2018), (that contributes to the researches of the National Oceanic and Atmospheric Administration) argue that it is premature to conclude that human activity, and particularly greenhouse warming, has already caused a detectable changein Atlantic hurricane activity. “Detectable” here means that the change is large enough to be distinguishable from the variability due to natural causes. Thus, they recognize the possibility that human activity may have alreadycaused some changes that are not yet detectable due to the small magnitude of the changes or observation limitations, or are not yet confidently modeled, but they don’t have a statistical response that could clearly claim that those events are not related to the inner variability of nature.
Thus, even if the present effects of the emissions of greenhouse gases (GHG), the main source of global warming coming from the human intervention, are still a matter of argument, the whole scientific community agrees on the point that global warming will be a key factor to face for the next century, for the harming effects that it could generate from different standpoints, economic, social, natural, etc.
The topic has been recently discussed among governors and gave life to the Kyoto protocol(adopted in 1997) and the Paris agreements(sealed in 2015), that represented the two main attempts of the international community to come together to commit to a common action in lowering the emission of GHS (such as carbonic dioxide and methane) in order to reduce global warming.
In particular, the Paris Agreement's explicit long-term goal is to keep the increase in global average temperature to “well below” 2 °C above pre-industrial levels and to limit the increase to 1.5 °C, since this would substantially reduce the risks and effects of climate change. On one hand the agreement had the merit of including 196 countries to the signatories, but on the other hand it has received many critics for the lack of any form of active enforcement. In fact, countries can set a voluntarytarget for emissions limitation, called a "nationally determined contribution”, in a sort of “name and shame” system that doesn’t captivate the opinion of some experts.
The half degree distinction cited in the Paris agreement, although might seem irrelevant, can have many important consequences.The most recent Intergovernmental Panel on Climate Change (IPCC) report, published in October 2018 warns about the differences in managing to keep the warming under 1.5°C or reaching 2°C.According to the IPCC report, managing to keep the increase at 1.5°C by year 2100, would avoid a 10 cm rise in the sea levels and would keep 10 million people away form danger due to coastal storms.Similarly, when it comes to heat waves, in a world that's warmed by up to 1.5C, about 14% of the population are exposed to a heat wave every five years. That increases to 37% of the population at 2°C.
Also if the 2°C threshold were reached, expert says that in some areas winter rainfalls could increase by 20% while summer rains could decrease by the same amount, contributing to droughts (increasing the probability of wildfires, like the Californian fires), damages to agricultural fields and reduction in tourism that would have an impact on the economy of the interested areas. On the other hand, the enlargement of winter falls can contribute to floods and destruction, like what Italy has experienced in the last weeks, causing huge damages in economic terms.The most immediate economic losses due to structural damages caused by extreme phenomena (hurricanes, floods, drought, fires) pair up with the “longer term” social issues, when several people will be obliged to migrate due to the climate conditions, and of course with the naturalistic consequences of the global warming. Reportedly the great iced territories, like Artic Ices, Antarctica and Greenland, are losing volume, contributing to the raise of sea levels and many ecosystems could be destroyed at the current pace of warming: a consistent portion of the coral reef is at risk and may disappear.
The IPCC report reveals that it is possible to limit global warming to 1.5°, especially thanks to the unexpected commitment of China (the country with the highest CO2 emissions) in decreasing GHG, but in order to reach the target, urgent, unprecedented and collective action must be taken. Global net human-caused emissions of carbon dioxide would need to fall by about 45 percent from 2010 levels by 2030, reaching ‘net zero’ around 2050. This situation tells that the commitment of investing on and developing renewable energies is crucial for countries and industries and population.
The growing importance of the topic has brought to the assignation of the Nobel prize to the Yale economist William Nordhaus for his studies, dated in the 90s, that describe the interaction between economy and climate change, considering nature not only as the framework in which economic life takes place, but recognizing it as an agent that is itself influenced by how the economic activity is run by humans.The climate emergency is calling again and it is time to give a concrete answer.
WRITTEN BY OLIVIERO BERTONI FOR BESA
PLEASE DIRECT ANY INQUIRY TO AS.BESA @UNIBOCCONI.IT
