TY - JOUR A1 - Bertram, Christoph A1 - Riahi, Keywan A1 - Hilaire, Jérôme A1 - Bosetti, Valentina A1 - Drouet, Laurent A1 - Fricko, Oliver A1 - Malik, Aman A1 - Nogueira, Larissa Pupo A1 - van der Zwaan, Bob A1 - van Ruijven, Bas A1 - van Vuuren, Detlef P. A1 - Weitzel, Matthias A1 - Longa, Francesco Dalla A1 - de Boer, Harmen-Sytze A1 - Emmerling, Johannes A1 - Fosse, Florian A1 - Fragkiadakis, Kostas A1 - Harmsen, Mathijs A1 - Keramidas, Kimon A1 - Kishimoto, Paul Natsuo A1 - Kriegler, Elmar A1 - Krey, Volker A1 - Paroussos, Leonidas A1 - Saygin, Deger A1 - Vrontisi, Zoi A1 - Luderer, Gunnar T1 - Energy system developments and investments in the decisive decade for the Paris Agreement goals JF - Environmental research letters N2 - The Paris Agreement does not only stipulate to limit the global average temperature increase to well below 2 °C, it also calls for 'making finance flows consistent with a pathway towards low greenhouse gas emissions'. Consequently, there is an urgent need to understand the implications of climate targets for energy systems and quantify the associated investment requirements in the coming decade. A meaningful analysis must however consider the near-term mitigation requirements to avoid the overshoot of a temperature goal. It must also include the recently observed fast technological progress in key mitigation options. Here, we use a new and unique scenario ensemble that limit peak warming by construction and that stems from seven up-to-date integrated assessment models. This allows us to study the near-term implications of different limits to peak temperature increase under a consistent and up-to-date set of assumptions. We find that ambitious immediate action allows for limiting median warming outcomes to well below 2 °C in all models. By contrast, current nationally determined contributions for 2030 would add around 0.2 °C of peak warming, leading to an unavoidable transgression of 1.5 °C in all models, and 2 °C in some. In contrast to the incremental changes as foreseen by current plans, ambitious peak warming targets require decisive emission cuts until 2030, with the most substantial contribution to decarbonization coming from the power sector. Therefore, investments into low-carbon power generation need to increase beyond current levels to meet the Paris goals, especially for solar and wind technologies and related system enhancements for electricity transmission, distribution and storage. Estimates on absolute investment levels, up-scaling of other low-carbon power generation technologies and investment shares in less ambitious scenarios vary considerably across models. In scenarios limiting peak warming to below 2 °C, while coal is phased out quickly, oil and gas are still being used significantly until 2030, albeit at lower than current levels. This requires continued investments into existing oil and gas infrastructure, but investments into new fields in such scenarios might not be needed. The results show that credible and effective policy action is essential for ensuring efficient allocation of investments aligned with medium-term climate targets. KW - Paris Agreement KW - energy investments KW - mitigation policies KW - climate policy KW - integrated assessment modelling Y1 - 2021 U6 - https://doi.org/10.1088/1748-9326/ac09ae SN - 1748-9326 VL - 16 IS - 7 PB - IOP Publishing CY - Bristol ER - 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 - RPRT A1 - Blanz, Alkis A1 - Eydam, Ulrich A1 - Heinemann, Maik A1 - Kalkuhl, Matthias T1 - Optimal carbon pricing with fluctuating energy prices — emission targeting vs. price targeting T2 - CEPA Discussion Papers N2 - Prices of primary energy commodities display marked fluctuations over time. Market-based climate policy instruments (e.g., emissions pricing) create incentives to reduce energy consumption by increasing the user cost of fossil energy. This raises the question of whether climate policy should respond to fluctuations in fossil energy prices? We study this question within an environmental dynamic stochastic general equilibrium (E-DSGE) model calibrated on the German economy. Our results indicate that the welfare implications of dynamic emissions pricing crucially depend on how the revenues are used. When revenues are fully absorbed, a reduction in emissions prices stabilizes the economy in response to energy price shocks. However, when revenues are at least partially recycled, a stable emissions price improves overall welfare. This result is robust to different modeling assumptions. T3 - CEPA Discussion Papers - 51 KW - energy prices KW - E-DSGE KW - climate policy KW - welfare Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-561049 SN - 2628-653X IS - 51 ER - TY - RPRT A1 - Hänsel, Martin C. A1 - Franks, Max A1 - Kalkuhl, Matthias A1 - Edenhofer, Ottmar T1 - Optimal carbon taxation and horizontal equity BT - A welfare-theoretic approach with application to German household data T2 - CEPA Discussion Papers N2 - We develop a model of optimal carbon taxation and redistribution taking into account horizontal equity concerns by considering heterogeneous energy efficiencies. By deriving first- and second-best rules for policy instruments including carbon taxes, transfers and energy subsidies, we then investigate analytically how horizontal equity is considered in the social welfare maximizing tax structure. We calibrate the model to German household data and a 30 percent emission reduction goal. Our results show that energy-intensive households should receive more redistributive resources than energy-efficient households if and only if social inequality aversion is sufficiently high. We further find that redistribution of carbon tax revenue via household-specific transfers is the first-best policy. Equal per-capita transfers do not suffer from informational problems, but increase mitigation costs by around 15 percent compared to the first- best for unity inequality aversion. Adding renewable energy subsidies or non-linear energy subsidies, reduces mitigation costs further without relying on observability of households’ energy efficiency. T3 - CEPA Discussion Papers - 28 KW - carbon price KW - horizontal equity KW - redistribution KW - renewable energy subsidies KW - climate policy KW - just transition Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-498128 SN - 2628-653X IS - 28 ER - TY - THES A1 - Schütze, Franziska T1 - Finance for a sustainable economy BT - implications for policy and practice BT - Implikationen für Politik und Praxis N2 - With his September 2015 speech “Breaking the tragedy of the horizon”, the President of the Central Bank of England, Mark Carney, put climate change on the agenda of financial market regulators. Until then, climate change had been framed mainly as a problem of negative externalities leading to long-term economic costs, which resulted in countries trying to keep the short-term costs of climate action to a minimum. Carney argued that climate change, as well as climate policy, can also lead to short-term financial risks, potentially causing strong adjustments in asset prices. Analysing the effect of a sustainability transition on the financial sector challenges traditional economic and financial analysis and requires a much deeper understanding of the interrelations between climate policy and financial markets. This dissertation thus investigates the implications of climate policy for financial markets as well as the role of financial markets in a transition to a sustainable economy. The approach combines insights from macroeconomic and financial risk analysis. Following an introduction and classification in Chapter 1, Chapter 2 shows a macroeconomic analysis that combines ambitious climate targets (negative externality) with technological innovation (positive externality), adaptive expectations and an investment program, resulting in overall positive macroeconomic outcomes. The analysis also reveals the limitations of climate economic models in their representation of financial markets. Therefore, the subsequent part of this dissertation is concerned with the link between climate policies and financial markets. In Chapter 3, an empirical analysis of stock-market responses to the announcement of climate policy targets is performed to investigate impacts of climate policy on financial markets. Results show that 1) international climate negotiations have an effect on asset prices and 2) investors increasingly recognize transition risks in carbon-intensive investments. In Chapter 4, an analysis of equity markets and the interbank market shows that transition risks can potentially affect a large part of the equity market and that financial interconnections can amplify negative shocks. In Chapter 5, an analysis of mortgage loans shows how information on climate policy and the energy performance of buildings can be integrated into risk management and reflected in interest rates. While costs of climate action have been explored at great depth, this dissertation offers two main contributions. First, it highlights the importance of a green investment program to strengthen the macroeconomic benefits of climate action. Second, it shows different approaches on how to integrate transition risks and opportunities into financial market analysis. Anticipating potential losses and gains in the value of financial assets as early as possible can make the financial system more resilient to transition risks and can stimulate investments into the decarbonization of the economy. N2 - Mit der Rede "Die Tragödie des Horizonts durchbrechen" im September 2015 hat der Präsident der englischen Zentralbank, Mark Carney, den Klimawandel auf die Agenda der Finanzmarktregulierer gebracht. Bis dahin wurde der Klimawandel vor allem als Problem einer negativen Externalität verstanden, welche langfristige Kosten verursacht. Dies führte dazu, dass sich die meisten Länder darauf konzentrieren, die kurzfristigen Kosten für Klimaschutzmaßnahmen auf ein Minimum zu reduzieren. Carney argumentierte, dass der Klimawandel, sowie Klimapolitik, auch zu kurzfristigen finanziellen Risiken führen kann, welche zu starken Anpassungen der Vermögenspreise führen können. Solche Auswirkungen zu untersuchen, stellt die traditionellen Wirtschafts- und Finanzmodelle jedoch vor Herausforderungen und erfordert ein tiefgreifenderes Verständnis der Zusammenhänge zwischen Klimapolitik und Finanzmärkten. Die vorliegende Arbeit untersucht daher die Auswirkungen der Klimapolitik auf die Finanzmärkte sowie die Rolle der Finanzmärkte in der Transformation zu einer nachhaltigeren Wirtschaft. Der Ansatz kombiniert Erkenntnisse aus der makroökonomischen Modellierung und der finanziellen Risikoanalyse. Nach einer Einführung und Einordnung in Kapitel 1, zeigt Kapitel 2 eine makroökonomische Analyse, welche ehrgeizige Klimaziele (negative Externalität) mit technologischer Innovationen (positive Externalität), adaptiven Erwartungen, sowie einem Investitionsprogramm kombiniert und damit zu positiven makroökonomischen Ergebnissen führt. Die Analyse zeigt auch die Grenzen klimaökonomischer Modelle in ihrer Darstellung der Finanzmärkte auf. Aus diesem Grund beschäftigt sich der nachfolgende Teil dieser Dissertation mit dem Zusammenhang zwischen Klimapolitik und Finanzmärkten. In Kapitel 3 wird eine empirische Analyse der Reaktionen von Aktienmärkten auf die Ankündigung klimapolitischer Ziele durchgeführt. Die Ergebnisse zeigen, dass sich internationale Klimaverhandlungen auf die Vermögenspreise auswirken und dass Investoren zunehmend Transformationsrisiken bei CO2-intensiven Firmen erkennen. Kapitel 4 zeigt, durch eine Analyse der Aktienmärkte und des Interbankenmarktes, dass Transformationsrisiken einen großen Teil des Aktienmarktes beeinflussen können und dass finanzielle Verflechtungen negative Schocks verstärken können. Kapitel 5 zeigt, durch eine Analyse von Hypothekenkrediten, wie Informationen über Klimapolitik und die Energieeffizienz von Gebäuden in das Risikomanagement integriert und sich damit im Zinssatz widerspiegeln können. Während die Kosten von Klimaschutzmaßnahmen in großem Umfang untersucht wurden, leistet diese Arbeit zwei wesentliche Beiträge. Erstens wird die Bedeutung eines grünen Investitionsprogramms zur Stärkung des makroökonomischen Nutzens von Klimaschutzmaßnahmen hervorgehoben. Zweitens zeigt diese Arbeit unterschiedliche Ansätze, wie Transformationsrisiken und -chancen in die Finanzmarktanalyse integriert werden können. Eine frühzeitige Erkennung und Einpreisung potenzieller Risiken und Chancen kann das Finanzsystem widerstandsfähiger machen und Investitionen in die Dekarbonisierung der Wirtschaft stimulieren. T2 - Die Finanzierung einer nachhaltigen Wirtschaft KW - Klimapolitik KW - climate policy KW - grüne Investitionen KW - green investments KW - sustainable finance KW - Nachhaltiges Finanzwesen Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-484415 ER -