Climate Change Economics in Vietnam: Redefining Economic Impact
Christian Otto, Christoph Schult, Thomas Vogt
Energy Economics,
Vol. 160 (August),
2026
Abstract
Vietnam, a low middle-income economy, grapples with considerable climate impacts, primarily driven by heat waves, sea level rise, and tropical cyclones. Under ongoing global warming, these extreme weather events are projected to further intensify. We use a dynamic general equilibrium model to study economic transition dynamics from 2015 to 2100, accounting for heat-induced labor productivity losses, agricultural land loss from sea level rise, and residential property damage from tropical cyclones. We compare a Paris-compatible strong mitigation scenario where global warming is limited to well below 2 °C above preindustrial levels to a strong emission scenario where warming reaches 4–5 °C. We find that the impacts of climate change on output and investment are highly uncertain, with differences between the two emission scenarios remaining statistically insignificant until the end of the century, despite substantially higher climate forcing in the latter. By contrast, consumption losses are significantly larger under the high emission scenario. These negative impacts are primarily driven by heat-induced labor productivity losses, while TCs are the main source of uncertainty. Our findings highlight the need for analytical frameworks to capture the different channels through which climate and climate change affect economic development, rather than focusing mainly on output-related damage, as done in many existing studies.
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Transition Dynamics in Heterogeneous-agent Models and the Distributional Consequences of Taxation
Alexandra Gutsch, Christoph Schult
IWH Discussion Papers,
No. 7,
2026
Abstract
We study how idiosyncratic income risk shapes the aggregate and distributional effects of labor and capital income taxation in dynamic general equilibrium models. To this end, we compare a heterogeneous-agent (HA) model with uninsurable idiosyncratic labor productivity risk and a ten-representative-agent (TE) model in which households correspond to fixed wealth deciles without such risk. At the aggregate level, both models generate qualitatively similar responses; however, the HA model exhibits a smaller recessionary impact driven by precautionary savings behavior, which stabilizes investment. At the distributional level, the models differ sharply. In the HA framework, tax shocks trigger endogenous mobility across wealth deciles. These inter-decile transition dynamics tend to benefit lower deciles. In contrast, the TA model features fixed household positions. Our findings highlight that while simpler multi-representative-agent models can approximate aggregate dynamics well, they may miss important distributional adjustment channels. The relevance of these mechanisms ultimately depends on the empirical importance of mobility across the wealth distribution, pointing to a key trade-off between model simplicity and accuracy.
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Road to Net Zero: Carbon Policy and Redistributional Dynamics in the Green Transition
Alessandro Sardone
IWH Discussion Papers,
No. 16,
2025
Abstract
This paper examines the macroeconomic and distributional effects of the European Union’s transition to Net Zero emissions through a gradually increasing carbon tax. I develop a New Keynesian Environmental DSGE model with two household types and distinct energy and non-energy sectors. Five alternative uses of carbon tax revenues are considered: equal transfers to households, targeted transfers to Hand-to-Mouth households, subsidies to green energy firms, and reductions in labor and capital income taxes. In the absence of technological progress, the carbon tax policy induces a persistent increase in energy prices and a reduction in GDP, investment, and consumption. Headline inflation falls below zero in the medium run, reflecting weaker aggregate demand. Distributional outcomes vary significantly depending on the implemented revenue recycling scheme: targeted transfers are the most progressive but entail larger macroeconomic costs, while subsidies and tax cuts mitigate output and investment losses but are less effective in narrowing the consumption gap. A limited foresight scenario, in which agents learn about policy targets sequentially, generates more volatile adjustment paths and temporary inflationary spikes around announcements, but long-run outcomes remain close to the baseline.
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Climate Change Economics in Vietnam: Redefining Economic Impact
Christian Otto, Christoph Schult, Thomas Vogt
Abstract
Vietnam, a lower-middle-income economy, faces severe climate risks from heat waves, sea-level rise, and tropical cyclones, which are expected to intensify under ongoing global warming. Using a dynamic general equilibrium model, we analyze economic transition dynamics from 2015 to 2100, incorporating heat-induced labor productivity losses, agricultural land loss, and cyclone-related property damage. We compare a Paris-compatible scenario limiting warming to below 2 °C with a high-emission scenario reaching 4–5 °C. While output and investment impacts remain highly uncertain and statistically indistinguishable across scenarios until 2100, consumption losses are significantly larger under high emissions, mainly driven by heat-related productivity declines, with cyclones contributing most to uncertainty. These findings underscore the importance of considering multiple impact channels beyond output damages in climate-development research.
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Die Verteilung und Struktur des deutschen Nationaleinkommens von 1992 bis 2019
Stefan Bach, Charlotte Bartels, Theresa Neef
Wirtschaft im Wandel,
No. 2,
2025
Abstract
Wie haben sich die Einkommen unterschiedlicher Bevölkerungsgruppen in Deutschland seit der Wiedervereinigung entwickelt? Unsere Studie untersucht die Entwicklung und Zusammensetzung des Nationaleinkommens entlang der Verteilung im Zeitraum von 1992 bis 2019. Während die untere Hälfte der Einkommensverteilung (unterhalb des Medianeinkommens) bis Mitte der 2000er Jahre reale Einkommensverluste verzeichnete, stiegen die Einkommen der oberen Mittelschicht (die obersten 10%, ohne das einkommensstärkste 1%) stetig. Die Spitzeneinkommen (oberstes 1%) blieben zwischen 1992 und 2019 relativ stabil. Arbeitseinkommen dominieren bei den unteren 99%, während das oberste 1% von Unternehmenseinkommen – insbesondere aus arbeitsintensiven Dienstleistungsunternehmen und freien Berufen – bestimmt ist. Unsere Ergebnisse sind zentral für die Debatte über Reformen der Sozialversicherungsbeiträge und der Einkommensbesteuerung.
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Die deutsche Investitionsschwäche: Warum gibt es sie, warum ist sie wichtig und was sollte die neue Bundesregierung dagegen tun?
Reint E. Gropp
Wirtschaft im Wandel,
No. 2,
2025
Abstract
Deutschland befindet sich schon im zweiten Jahr in einer Rezession, und Wachstum ist laut den Prognosen der Wirtschaftsforschungsinstitute auch 2025 kaum zu erwarten. Viel schlimmer ist allerdings, dass neue Prognosen des langfristigen Wachstums im Gleichgewicht (das so genannte Produktionspotenzial) dramatisch niedrigere Wachstumsraten für die nächsten 20 Jahre vorhersagen, wenn sich die Wirtschaftspolitik nicht deutlich ändert. Eine wesentliche Ursache für die Wachstumsschwäche ist die Investitionsschwäche. Um diese anzugehen, reicht das beschlossene Sondervermögen für Infrastruktur nicht aus. Die neue Bundesregierung muss die Bürokratie abbauen und Planungsverfahren verkürzen, eine rationale Klima- und Energiepolitik verfolgen, das Rentensystem mutig in Richtung Kapitaldeckungsverfahren umbauen und eine Einkommensteuerreform auf den Weg bringen, die mittlere Einkommen entlastet.
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