@IvoHlebarov@PeterGleick@MichaelEMann@JKSteinberger@KHayhoe It is what the IPCC says. The way framed in the thread is not quite correct. Yes, the 50% and net zero 2050 is based on scenarios with carbon dioxide removal. You can do stylised with a carbon budget, and take the numbers from SR15 Table 2.2.
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@IvoHlebarov@PeterGleick@MichaelEMann@JKSteinberger@KHayhoe If we just accept these numbers (& not quibble over temp baselines, feedbacks, etc). These budgets are defined on when emissions reach zero (and temperature is about peak). The IPCC statement is equivalent to 50% 1.5C (at peak).
You want 66%, the 420GtCO2 budget? There are no scenarios in the literature, that I know of, that can do that!
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@IvoHlebarov@PeterGleick@MichaelEMann@JKSteinberger@KHayhoe To say it is a dangerous myth will get lots of retweets, but is itself a dangerous myth. I am not sure what the object is? Yes, quite ok to be critical of CO2 removal (as I have), but that is a different issue issue if you ask me.
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@IvoHlebarov@PeterGleick@MichaelEMann@JKSteinberger@KHayhoe And the point here is not to put in criteria which makes 1.5C seem harder & harder. The point is to stay below 1.5C (or well below 2C if you are into Paris). To do that, we need to reduce emissions, probably faster than we realistically could (disagree? Look out the window)
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Record high emissions means record high radiative forcing.
We have you covered, we also include aerosols (SO2, etc) & have done so for decades. Also shipping!
Short-lived aerosols are important, but should not distract from the drivers of change: greenhouse gas emissions!
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Most of the energy put into the system ends in the ocean (90%), so the Ocean Heat Content (OHC) has been increasing along with emissions and radiative forcing.
This also means the Earth Energy Imbalance is also increasing.
This question is ambiguous: "How high above pre-industrial levels do you think average global temperature will rise between now and 2100?"
* ...pre-industrial... between "now and 2100"?
* Where we are currently heading or where we could head? This is largely a policy question?
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One of the key arguments that Norway uses to continue oil & gas developments, is that under BAU it is expected that oil & gas production will decline in line with <2°C scenarios, even with continued investment.
Let's look closer at these projections & reality...
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Here is the projections from the 2003 report from the petroleum agency.
In reality (tweet 1) there was a dip around 2010, but production is now up around 250 million cubic again.
The forecast was totally & utterly WRONG!
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In 2011 there was a forecast for an increase in production to 2020, but then a decline. This is probably since they started to put the Johan Sverdrup field on the books.
The increase in production was way too low, again, they got it wrong.