The CO2
emissions as per the USA, China, and EU stated goals have been estimated to
yield a 0.2 degree C temperature reduction by 2050. This figure was estimated
assuming all other nations followed either the USA or the Chinese commitments (I
assumed the EU commitment is too stupid to be copied by other nations).
The USA China agreement is soft, Obama celebrated the deal with Chinese President Xi Jinping last week. He seemed really happy he got the Chinese to stop growing their emissions after 2030.
Obama toasts the big deal with Xi Jingping
If we follow my method then we have three sets of CO2 emissions commitments:
i. EU commitment, 40 % reduction by
2030.
ii. USA commitment, 28 % reduction by
2025.
iii. China commitment, continued growth
and no more increases beyond 2030.
Given the
lack of stated commitments by other nations, I used my judgment and placed them
in one of the three groups above. I also extrapolated these commitments
assuming all nations except for Africa would continue reducing their CO2 emissions
by 2.1 % per year. This happens to be the reduction the USA has to use to
achieve Obama´s pledge to the Chinese.
The Chinese
and other Asian nations (except Japan and South Korea) are the gorillas in the CO2 emissions
scenarios. Because they, as well as minor players (Latin America, former Soviet
Union, and so on) do not reduce emissions growth until 2030 the total world´s
emissions will continue to rise and peak at 20 % above today´s level, as shown
in this graph:
CO2
emissions if all nations participate
in CO2 reduction efforts in three classes…
However, if
we assume 50 % of the CO2 emissions do not stay in the atmosphere (this is
roughly what happened over the last century), then CO2 concentrations reach 493
ppm by 2050 (versus 536 ppm if we use my estimate of fossil fuel burn rate,
documented in a previous post).
But CO2
concentration isn´t really what has Obama worried. He´s worried about
temperature increases. So I took an equation (which I think is fairly conservative) from Clive Best´s blog and
estimated temperature increase caused by two CO2 emissions scenarios:
a. The Agreement Scenario as described
above.
b. The Fossil Fuel Reserves Scenario,
which uses the CO2 emissions caused by the consumption of all the fossil fuel
reserves (as shown by BP in their World Energy Factbook).
The
estimated temperature change due to the Agreement versus that of a “free market”
fossil fuel burn rate is much lower: the agreement scenario yields a 0.2 degree
C temperature difference! The actual temperature anomaly is 1.3 degrees C
versus 1.5 degrees C if we essentially do nothing.
This temperature anomaly is versus the temperature in 1750. Today´s temperature is about 0.8 degrees C higher. This means one has to cut the 1.3 to 0.5 and the 1.5 to 0.7 degrees C above the 2013 world average to get the 2050 number.
This temperature anomaly is versus the temperature in 1750. Today´s temperature is about 0.8 degrees C higher. This means one has to cut the 1.3 to 0.5 and the 1.5 to 0.7 degrees C above the 2013 world average to get the 2050 number.
Look at these results:
CO2 concentration and temperature resulting from two scenarios
This is
really good news, because as we all know a temperature increase below 2 degrees
C (or 1.2 versus last year´s temperature) will keep us safe from those super hurricanes and megadroughts Al Gore
mentions. And it will also allow polar bears to survive, and the huge violence
and crime we expect from global warming won´t really happen. So I´m pretty
happy with the whole thing.
The only
thing which worries me is the cost to reduce emissions as these guys have
projected, and what happens if the Chinese, the Indians and everybody else but
the EU and the USA refuses to reduce their emissions. If they continue to burn
fossil fuels then we may have to nuke them to make them stop? This potential
scenario does kinda worry me.
References
The problem is that Obama did not actually get China to agree to anything at all.
ResponderEliminarThat is right. I used the supposed agreement to see what would happen. I don't think what I assumed is reasonable. Most nations won't go along.
Eliminar