|The fog of warm|
The definition of "civilization", for the purposes of this series, is defined by two posts "What Do You Mean - World Civilization?", and "Confusing 'Civilization' With 'Species'."
A peer reviewed report written for The World Bank and prepared by the Potsdam Institute for Climate Impact Research and Climate Analytics has been circulated since about November of this year.
The title of that report is "Why a 4°C Warmer World Must Be Avoided", and is available for download in a link that follows.
One of the first questions that naturally arises is "where did they get the four degree celsius ("4°C") figure?"
The answer to that question is in the report itself:
It is my hope that this report shocks us into action. Even for those of us already committed to fighting climate change, I hope it causes us to work with much more urgency.(Why a 4°C Warmer World Must Be Avoided, emphasis added). Ok, so the scientific establishment came up with the four degrees, so let's look further to what else they said:
This report spells out what the world would be like if it warmed by 4 degrees Celsius, which is what scientists are nearly unanimously predicting by the end of the century, without serious policy changes.
The 4°C scenarios are devastating: the inundation of coastal cities; increasing risks for food production potentially leading to higher malnutrition rates; many dry regions becoming dryer, wet regions wetter; unprecedented heat waves in many regions, especially in the tropics;(ibid, emphasis added). In other words they are saying it would be bad beyond the beyond, but could even be surprisingly worse than that in some ways.
substantially exacerbated water scarcity in many regions; increased frequency of high-intensity tropical cyclones; and irreversible loss of biodiversity [species], including coral reef systems.
Coastal cities are endangered
And most importantly, a 4°C world is so different from the current one that it comes with high uncertainty and new risks that threaten our ability to anticipate and plan for future adaptation needs.
The lack of action on climate change not only risks putting prosperity out of reach of millions of people in the developing world, it threatens to roll back decades of sustainable development.
It is clear that we already know a great deal about the threat before us. The science is unequivocal that humans are the cause of global warming ...
The previous post in this series is here.
The lyrics to the following song are here.