Uncertain 2 Degrees J Baehr I Hense L
Uncertain 2 Degrees J. Baehr, I. Hense, L. Kutzbach, S. Rödder, M. Scheffold, J. Scheffran Session 4, 24. 04. 2019 Uncertainty in Climate Modellingphysical perspective Lecturer: Johanna Baehr Moderator: Lars Kutzbach Course coordination: Lars Kutzbach, Simone Rödder, Maike Scheffold
Today's Schedule Uncertainty talks (role-play 30 min, plenary discussion 15 min) Lecture Johanna Baehr (30 min): Uncertainty in climate modelling - physical perspective Homework 4 (10 min)
Uncertainty talks: ”How certain are we that the global average near-surface air temperature has increased since 1850? ”
Uncertainty in climate modelling § All models are wrong, . . . George Box, 1976
Uncertainty in climate modelling § All models are wrong, but some are useful. George Box, 1976 § What we might aim for: § not: reducing uncertainty § maybe: increasing certainty § or possibly: increasing confidence § most likely: ‚adequacy for purpose‘ (W. Parker, 2009) § Today‘s purpose: § Statement about future climate evolution Wendy Parker, 10. 1111/j. 1467 -8349. 2009. 00180. x
RCP 8. 5 RCP 4. 5 RCP 2. 6
Uncertainty in climate modelling § Today‘s purpose: § Statement about future climate evolution § Future climate projections heavily depend on chosen scenario §. . . and on the model
SPM
Uncertainty in climate modelling § Today‘s purpose: § Statement about future climate evolution § Future climate projections heavily depend on chosen scenario §. . . and on the model § How to find out whether the model is ‚adequate for the purpose‘?
10
Uncertainty in climate modelling § Today‘s purpose: § Statement about future climate evolution § Future climate projections heavily depend on chosen scenario §. . . and on the model § How to find out whether the model is ‚adequate for the purpose‘? § For past climate evolution: comparison to observations § Multi-model analysis § Sensitivity analysis
All forcing AR 5, TSM
All forcing Natural forcing only AR 5, TSM
Uncertainty in climate modelling § Today‘s purpose: § Statement about future climate evolution § Future climate projections heavily depend on chosen scenario §. . . and on the model § How to find out whether the model is ‚adequate for the purpose‘? § For past climate evolution: comparison to observations (empirical) § Multi-model analysis (robustness) § Sensitivity analysis (classical test to estimate epistemic uncertainty) § Possibly: § (re-)define question/purpose? § check wording of answer. . .
SPM
Literature • IPCC AR 4, FAQ 8. 1: How Reliable Are the Models Used to Make Projections of Future Climate Change? https: //www. ipcc. ch/publications_and_data/ar 4/wg 1/en/faq-81. html • IPCC AR 5, Ch. 9 • Parker, e. g. , 2009: 10. 1111/j. 1467 -8349. 2009. 00180. x • Baumberger et al. , 2017: 10. 1002/wcc. 454
Homework – 4 PART 1 Due: 1 rst May For the bloggers: post a blog entry about role-play 1. Give your arguments, show differences, similarities, difficulties or processes you experienced… (This entry counts into the blog count. Use your username as author only. ) Further instructions on the next slide or see How to…add a blog post and How to…create a featured image on the blog. If you run into any problems, please contact Maike Scheffold (maike. scheffold@unihamburg. de) by 26 th April. Homework – 4 PART 2 Due: 7 th May For the students supposed to comment: choose one of the blog posts of your fellow students and comment on it. You are free to choose on what you want to comment (argumentation, different viewpoint, your perspective, perspective of one of the roles involved in the role-play…). However, make sure to be constructive and positive. See Guidelines for discussions, How to… comment on a blog post and How to… give feedback on the blog. If you run into any problems, please contact Maike Scheffold (maike. scheffold@unihamburg. de) by 6 th May.
Homework – 4 PART 3 (all) Due: 8 th May In the lecture on 8 th May, we start preparing the panel discussion for 26 th June (instead of role-playing). The topic of the panel will be “Sense and nonsense of the 2 -degrees-limit. Does such a limit make sense? How certain are we that we can reach it? ” As your input for the preparation session, please work on the following questions: • What are relevant perspectives and interesting positions with regard to the aim and scope of the panel discussion? • Who would be an appropriate speaker to put forward a relevant perspective (someone who has voiced an interesting and/or controversial position)? Please limit your scope to speakers that we can indeed invite, e. g. who are located in the Hamburg area. Please make notes on your research and bring them to class on 8 th May to inform our plenum discussion and planning. If you run into any problems, please contact Maike Scheffold (maike. scheffold@unihamburg. de) by 6 th May.
Set category: Role-play 1_2019 Min. Tags: Role-play, ideas Use the featured image according to your role • You will find a collection of images under Media • Feel free to adapt your featured image – see How to …create a featured image
- Slides: 19