Re: THE DISCOVERY OF GLOBAL WARMING
Posted: Fri Jan 31, 2020 1:40 p
Often overlooked in the 2013 IPCC report was a statement about the world's permissible "carbon budget."
Two landmark articles published in 2009 had taken a new approach to global warming.
Avoiding the complexities of calculating one or another "pathway" of greenhouse emissions over the decades, the authors simply asked how much warming would arise from a given total amount of fossil fuel carbon emitted into the atmosphere.
It turned out that regardless of the pathway, the world was liable to pass beyond the 2°C limit for "dangerous" climate change if more than another trillion tons of fossil fuels were burned after the year 2000.
Since more than a quarter of that had already been burned, "less than half the proven economically recoverable oil, gas and coal reserves can still be emitted up to 2050 to achieve such a goal."
Diplomats shied away from the politically unthinkable problem of dividing up the remaining emissions (notably how to treat developed nations, which had already emitted far more than their equitable share).
Everyone agreed that a strong Kyoto-style comprehensive treaty was out of reach, and the future would have to rely on nations spurring and shaming each other into local pledges.
Some observers advised that it was time to give up the chaotic and time-consuming FCCC process altogether and settle for whatever could be negotiated among smaller groups of parties.
The European Union took the lead.
In October 2014, after complex negotiations, the EU's national leaders issued a joint pledge that by 2030 they would cut their combined greenhouse emissions by at least 40% from 1990 levels, and would get at least 27% of their energy from renewable sources.
Further hopes were raised in November by a diplomatic breakthrough between the United States and China, nations that together were producing nearly half the world's greenhouse gases.
Groundwork had been laid the previous year by a pact to restrict their hydrofluorocarbons (HFCs), a potent greenhouse gas.
Now the American President, Barack Obama, promised that his nation would reduce carbon emissions at least 26% below 2005 levels by 2025; China promised that its CO2 emissions would peak by 2030 and that the fraction of its energy produced by low-carbon sources would climb to 20% by then.
Both goals were achievable if the nations' current policies were continued and pursued aggressively.
However, it was far from clear whether the US political and legal system would allow Obama to follow through on his promise.
In December 2014, national representatives debated fiercely for two weeks in Lima, Peru, preparatory to a major conference scheduled for the following year.
In the end they could only agree to present national plans for voluntary cuts.
It was the first time that all nations, notably including the developing ones, had agreed to make any sort of cuts.
TO BE CONTINUED ...
Two landmark articles published in 2009 had taken a new approach to global warming.
Avoiding the complexities of calculating one or another "pathway" of greenhouse emissions over the decades, the authors simply asked how much warming would arise from a given total amount of fossil fuel carbon emitted into the atmosphere.
It turned out that regardless of the pathway, the world was liable to pass beyond the 2°C limit for "dangerous" climate change if more than another trillion tons of fossil fuels were burned after the year 2000.
Since more than a quarter of that had already been burned, "less than half the proven economically recoverable oil, gas and coal reserves can still be emitted up to 2050 to achieve such a goal."
Diplomats shied away from the politically unthinkable problem of dividing up the remaining emissions (notably how to treat developed nations, which had already emitted far more than their equitable share).
Everyone agreed that a strong Kyoto-style comprehensive treaty was out of reach, and the future would have to rely on nations spurring and shaming each other into local pledges.
Some observers advised that it was time to give up the chaotic and time-consuming FCCC process altogether and settle for whatever could be negotiated among smaller groups of parties.
The European Union took the lead.
In October 2014, after complex negotiations, the EU's national leaders issued a joint pledge that by 2030 they would cut their combined greenhouse emissions by at least 40% from 1990 levels, and would get at least 27% of their energy from renewable sources.
Further hopes were raised in November by a diplomatic breakthrough between the United States and China, nations that together were producing nearly half the world's greenhouse gases.
Groundwork had been laid the previous year by a pact to restrict their hydrofluorocarbons (HFCs), a potent greenhouse gas.
Now the American President, Barack Obama, promised that his nation would reduce carbon emissions at least 26% below 2005 levels by 2025; China promised that its CO2 emissions would peak by 2030 and that the fraction of its energy produced by low-carbon sources would climb to 20% by then.
Both goals were achievable if the nations' current policies were continued and pursued aggressively.
However, it was far from clear whether the US political and legal system would allow Obama to follow through on his promise.
In December 2014, national representatives debated fiercely for two weeks in Lima, Peru, preparatory to a major conference scheduled for the following year.
In the end they could only agree to present national plans for voluntary cuts.
It was the first time that all nations, notably including the developing ones, had agreed to make any sort of cuts.
TO BE CONTINUED ...