TY  - JOUR
A1  - Harmsen, Mathijs
A1  - Kriegler, Elmar
A1  - van Vuuren, Detlef P.
A1  - van der Wijst, Kaj-Ivar
A1  - Luderer, Gunnar
A1  - Cui, Ryna
A1  - Dessens, Olivier
A1  - Drouet, Laurent
A1  - Emmerling, Johannes
A1  - Morris, Jennifer Faye
A1  - Fosse, Florian
A1  - Fragkiadakis, Dimitris
A1  - Fragkiadakis, Kostas
A1  - Fragkos, Panagiotis
A1  - Fricko, Oliver
A1  - Fujimori, Shinichiro
A1  - Gernaat, David
A1  - Guivarch, Céline
A1  - Iyer, Gokul
A1  - Karkatsoulis, Panagiotis
A1  - Keppo, Ilkka
A1  - Keramidas, Kimon
A1  - Köberle, Alexandre
A1  - Kolp, Peter
A1  - Krey, Volker
A1  - Krüger, Christoph
A1  - Leblanc, Florian
A1  - Mittal, Shivika
A1  - Paltsev, Sergey
A1  - Rochedo, Pedro
A1  - van Ruijven, Bas J.
A1  - Sands, Ronald D.
A1  - Sano, Fuminori
A1  - Strefler, Jessica
A1  - Arroyo, Eveline Vasquez
A1  - Wada, Kenichi
A1  - Zakeri, Behnam
T1  - Integrated assessment model diagnostics
BT  - key indicators and model evolution
JF  - Environmental research letters
N2  - Integrated assessment models (IAMs) form a prime tool in informing about climate mitigation strategies. Diagnostic indicators that allow comparison across these models can help describe and explain differences in model projections. This increases transparency and comparability. Earlier, the IAM community has developed an approach to diagnose models (Kriegler (2015 Technol. Forecast. Soc. Change 90 45–61)). Here we build on this, by proposing a selected set of well-defined indicators as a community standard, to systematically and routinely assess IAM behaviour, similar to metrics used for other modeling communities such as climate models. These indicators are the relative abatement index, emission reduction type index, inertia timescale, fossil fuel reduction, transformation index and cost per abatement value. We apply the approach to 17 IAMs, assessing both older as well as their latest versions, as applied in the IPCC 6th Assessment Report. The study shows that the approach can be easily applied and used to indentify key differences between models and model versions. Moreover, we demonstrate that this comparison helps to link model behavior to model characteristics and assumptions. We show that together, the set of six indicators can provide useful indication of the main traits of the model and can roughly indicate the general model behavior. The results also show that there is often a considerable spread across the models. Interestingly, the diagnostic values often change for different model versions, but there does not seem to be a distinct trend.
KW  - diagnostics
KW  - integrated assessment models
KW  - climate policy
KW  - Assessment Report IPCC
KW  - renewable energy
KW  - migration
KW  - AR6
Y1  - 2021
U6  - https://doi.org/10.1088/1748-9326/abf964
SN  - 1748-9326
VL  - 16
IS  - 5
PB  - IOP Publishing
CY  - Bristol
ER  - 
TY  - JOUR
A1  - van Soest, Heleen L.
A1  - Aleluia Reis, Lara
A1  - Baptista, Luiz Bernardo
A1  - Bertram, Christoph
A1  - Després, Jacques
A1  - Drouet, Laurent
A1  - den Elzen, Michel
A1  - Fragkos, Panagiotis
A1  - Fricko, Oliver
A1  - Fujimori, Shinichiro
A1  - Grant, Neil
A1  - Harmsen, Mathijs
A1  - Iyer, Gokul
A1  - Keramidas, Kimon
A1  - Köberle, Alexandre C.
A1  - Kriegler, Elmar
A1  - Malik, Aman
A1  - Mittal, Shivika
A1  - Oshiro, Ken
A1  - Riahi, Keywan
A1  - Roelfsema, Mark
A1  - van Ruijven, Bas
A1  - Schaeffer, Roberto
A1  - Silva Herran, Diego
A1  - Tavoni, Massimo
A1  - Ünlü, Gamze
A1  - Vandyck, Toon
A1  - van Vuuren, Detlef P.
T1  - Global roll-out of comprehensive policy measures may aid in bridging emissions gap
JF  - Nature communications
N2  - Closing the emissions gap between Nationally Determined Contributions (NDCs) and the global emissions levels needed to achieve the Paris Agreement’s climate goals will require a comprehensive package of policy measures. National and sectoral policies can help fill the gap, but success stories in one country cannot be automatically replicated in other countries. They need to be adapted to the local context. Here, we develop a new Bridge scenario based on nationally relevant, short-term measures informed by interactions with country experts. These good practice policies are rolled out globally between now and 2030 and combined with carbon pricing thereafter. We implement this scenario with an ensemble of global integrated assessment models. We show that the Bridge scenario closes two-thirds of the emissions gap between NDC and 2 °C scenarios by 2030 and enables a pathway in line with the 2 °C goal when combined with the necessary long-term changes, i.e. more comprehensive pricing measures after 2030. The Bridge scenario leads to a scale-up of renewable energy (reaching 52%–88% of global electricity supply by 2050), electrification of end-uses, efficiency improvements in energy demand sectors, and enhanced afforestation and reforestation. Our analysis suggests that early action via good-practice policies is less costly than a delay in global climate cooperation.
KW  - climate-change mitigation
KW  - climate-change policy
Y1  - 2021
U6  - https://doi.org/10.1038/s41467-021-26595-z
N1  - Corrigendum: https://doi.org/10.1038/s41467-022-27969-7
VL  - 12
IS  - 1
PB  - Nature Publishing Group UK
CY  - London
ER  - 
TY  - JOUR
A1  - Duan, Hongbo
A1  - Zhou, Sheng
A1  - Jiang, Kejun
A1  - Bertram, Christoph
A1  - Harmsen, Mathijs
A1  - Kriegler, Elmar
A1  - van Vuuren, Detlef P.
A1  - Wang, Shouyang
A1  - Fujimori, Shinichiro
A1  - Tavoni, Massimo
A1  - Ming, Xi
A1  - Keramidas, Kimon
A1  - Iyer, Gokul
A1  - Edmonds, James
T1  - Assessing China’s efforts to pursue the 1.5°C warming limit
JF  - Science
N2  - Given the increasing interest in keeping global warming below 1.5°C, a key question is what this would mean for China’s emission pathway, energy restructuring, and decarbonization. By conducting a multimodel study, we find that the 1.5°C-consistent goal would require China to reduce its carbon emissions and energy consumption by more than 90 and 39%, respectively, compared with the “no policy” case. Negative emission technologies play an important role in achieving near-zero emissions, with captured carbon accounting on average for 20% of the total reductions in 2050. Our multimodel comparisons reveal large differences in necessary emission reductions across sectors, whereas what is consistent is that the power sector is required to achieve full decarbonization by 2050. The cross-model averages indicate that China’s accumulated policy costs may amount to 2.8 to 5.7% of its gross domestic product by 2050, given the 1.5°C warming limit.
Y1  - 2021
U6  - https://doi.org/10.1126/science.aba8767
SN  - 1095-9203
SN  - 0036-8075
VL  - 372
IS  - 6540
SP  - 378
EP  - 385
PB  - American Association for the Advancement of Science
CY  - Washington, DC
ER  -