Scenarios, carbon budgets and temperature projections in the new IPCC WG1 AR6 report

A/Prof Malte Meinshausen and Zebedee Nicholls, 10 August 2021.

The Physical Science (Working Group 1) contribution to the IPCC’s Sixth Assessment Report was released on the 10th August 2021. This first of two seminars will provide an overview of some key results in the IPCC report, presented by two authors that have been closely involved in this IPCC cycle. The seminar will cover the new scenarios that underpin future projections, historical warming updates, the question around how these scenarios compare to 1.5C warming, a comparison of when peak warming levels could be reached under the low mitigation scenarios, the impact of COVID, techniques to provide assessed future temperature projections based on multiple lines of evidence, the usefulness of providing projections against warming levels, remaining carbon budgets in comparison to the SR.5 report, as well as the importance of CO2 versus other gases, both in terms of past and future warming as well as in terms of so-called metrics that compare unit emissions of different GHGs. The second seminar (24th August) will provide more technical detail on two key aspects, i.e. assessed future warming levels and remaining carbon budgets.

This seminar is part of a series being hosted by the Climate and Energy College in 2021 that is supported by the Strategic Partnership for Implementation of the Paris Agreement.

[____________aaaaaaaaaaaaaaaaa]

2014 projections 1.5 by 2050 at the latest. 2021 projections 1.5 by late 2030s. 2028 projections... “oops” we just passed 1.5. Were fucked!

[cupsCoffee]

This presentation is emphasizing the best case scenario and not engaging with the other scenarios. I guess you don’t want people to get discouraged and give up? I think people should be scared into their wits by this data. Lots of hand waving. This is how I talk to my grandson. And this is how my doctor talks to me. Like I’m 5.

Lol “remaining carbon budgets”, that’s like a budget you get from a payday loan

[annakarenina]

Gusy: plz listen to actual scientists and not random people in in youtube comments. thx

[kadran]

We are completely fkt. The best we can hope for is +3ºC but this is unlikely.

[jonathanedwardgibson]

This is a journey to another planet. Not the one Musk planned. When we come out the other end there will be different plants and animals and weather and people.
We are locked-in to three decades of ever-hotter and awful weather, even if we took hammers to all the dinosaur-fart burning machinery today. Everything we’ve invested and built this last century is already obsolete… by about 100 years, but nobody feels it just yet. Our structures expect the different heating, humidity, pests, water tables, etc of bygones. Every construction must be questioned. This means freezing today’s power plants, airport expansions, and new refineries NOW. Is that an emergency freeway, or not? Get real.

[nl]

utter nonsense from guy saying 1.5 breech is not possible you dont even factor in ocean die off, forests emiting carbon instead of being sinks, oceans releasing carbon fromthe 40, 000 billion tonnes of legacy emmissons and so on. yes well done on the models and lots of work, but our mother is a holistic living organism and you guys ignore that

[callummackay]

The CO2 LEVEL WITHIN OUR ATMOSPHERE BY PERCENTAGE IS 0.04. MINUSCULE
WHY DO WE VILIFY CARBON.. ITS ALL ABOUT THE CARBON TAX. AH-AH

[rudigereichler]

paint that color curtain back to 7000 years ago if you are talking about climate seriously.

[drdusandr]

Without CO2 there is no life. Co2 is so rare commodity and you want to produce stone with it.
(All continental mountains like Himalaia, Andies, Alps, etc. are made of CO2 from the air by life). Plants grow faster, bigger because there is at least twice as much CO2 the century ago (ask farmers which produce plants in greenhouses, they put even 2x more CO2 and the temperature is even higher. Plants can close their pores to reduce dehydration due to heath because they can get CO2 faster. CO2 is GOOD GOOD NOT bad. CO2 is not C carbon.

[wallyblackler]

Let’s start this off with a hockey stick is a lie

[richardsb]

Climate does not rely on computer generated projections but on natural processes the most important being the sun's output of energy reaching the earth's surface. Any discussion which fails to accept the major role of the sun is doomed to reach conclusions which will fail to match actual climate outcomes. Hence the never-ending predictions that Arctic sea-ice will disappear during the summer whilst the sea-ice refuses to obey climate alarmists, is a clear example of the obsession with man-made climate change obstructing scientific assessment of why climate is always changing as it has done so, for the entire history of the earth.

[davidmcdonald]

better off looking at the HARTLAND INSTITUTE youtube vids

[nxgrs]

The ubiquitous K-T atmospheric heat budget shows 63 W/m^2 LWIR upwelling from the surface
This value appears TWICE!
Once sourced from the net, net solar energy 161 that arrived from the sun. Since it is not shown it must have slipped behind the sofa.
Second as part of the theoretical, “what if?” calculation for a BB at the surface temperature of 16 C used to calculate emissivity, i.e. 63/396=0.16.
When the music stops the solar 66 has chair in which to sit.
The calc’d 66 does not.
The greenhouse effect is a fifth grade math error.