Stefan Rahmstorf's research while affiliated with Universität Potsdam and other places

Publications (241)

Article
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Non-technical summary We summarize some of the past year's most important findings within climate change-related research. New research has improved our understanding about the remaining options to achieve the Paris Agreement goals, through overcoming political barriers to carbon pricing, taking into account non-CO 2 factors, a well-designed implem...
Article
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Over the last decade, the world warmed by 0.25 °C, in-line with the roughly linear trend since the 1970s. Here we present updated analyses showing that this seemingly small shift has led to the emergence of heat extremes that would be virtually impossible without anthropogenic global warming. Also, record rainfall extremes have continued to increas...
Conference Paper
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Here, we examine the impacts of significant atmospheric circulation changes at seasonal scales on European temperature and precipitation and disentangle the thermodynamical from the dynamical contributions, under increasing CO2 concentrations. We use a very high resolution fully-coupled global climate model (CM2.6 GFDL), to document significant cha...
Article
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The Atlantic Meridional Overturning Circulation (AMOC)—one of Earth’s major ocean circulation systems—redistributes heat on our planet and has a major impact on climate. Here, we compare a variety of published proxy records to reconstruct the evolution of the AMOC since about ad 400. A fairly consistent picture of the AMOC emerges: after a long and...
Article
Full-text available
In their comment on our paper (Caesar et al 2020 Environ. Res. Lett. 15 024003), Chen and Tung (hereafter C&T) argue that our analysis, showing that over the last decades Atlantic meridional overturning circulation (AMOC) strength and global mean surface temperature (GMST) were positively correlated, is incorrect. Their claim is mainly based on two...
Article
Changes in atmospheric circulation under increasing greenhouse gas concentrations are important because of their implications for weather extremes and associated societal risks. However, uncertainties in models and future projections are still large and drivers behind circulation changes are not well understood. Particularly for Europe, a potential...
Article
This work reviews the literature on an alleged global warming 'pause' in global mean surface temperature (GMST) to determine how it has been defined, what time intervals are used to characterise it, what data are used to measure it, and what methods used to assess it. We test for 'pauses', both in the normally understood meaning of the term to mean...
Article
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Article
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Berlin, October 2, 2020 | Scientists for Future (S4F) confirm that the demands of Fridays for Future (FFF) on EU politics are factually necessary and scientifically justified. According to IPCC calculations , the EU27 will have a residual budget for emissions of 20 Gt CO from 2021 to limit global warming to a maximum of 1.5 degrees. An 80% reductio...
Conference Paper
The future response of the Antarctic ice sheet to rising temperatures remains highly uncertain. A useful period for assessing the sensitivity of Antarctica to warming is the Last Interglacial (LIG) (129 to 116 ky), which experienced warmer polar temperatures and higher global mean sea level (GMSL) (+6 to 11 m) relative to present day. LIG sea level...
Article
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Sea-level rise projections and knowledge of their uncertainties are vital to make informed mitigation and adaptation decisions. To elicit projections from members of the scientific community regarding future global mean sea-level (GMSL) rise, we repeated a survey originally conducted five years ago. Under Representative Concentration Pathway (RCP)...
Article
Full-text available
The future response of the Antarctic ice sheet to rising temperatures remains highly uncertain. A useful period for assessing the sensitivity of Antarctica to warming is the Last Interglacial (LIG) (129 to 116 ky), which experienced warmer polar temperatures and higher global mean sea level (GMSL) (+6 to 9 m) relative to present day. LIG sea level...
Article
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According to established understanding, deep-water formation in the North Atlantic and Southern Ocean keeps the deep ocean cold, counter-acting the downward mixing of heat from the warmer surface waters in the bulk of the world ocean. Therefore, periods of strong Atlantic meridional overturning circulation (AMOC) are expected to coincide with cooli...
Article
The growing threat of abrupt and irreversible climate changes must compel political and economic action on emissions. The growing threat of abrupt and irreversible climate changes must compel political and economic action on emissions. A plane flying over a river of meltwater on glacier in Alaska
Article
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The summer of 2018 witnessed a number of extreme weather events such as heatwaves in North America, Western Europe and the Caspian Sea region, and rainfall extremes in South-East Europe and Japan that occurred near-simultaneously. Here we show that some of these extremes were connected by an amplified hemisphere-wide wavenumber 7 circulation patter...
Conference Paper
Full-text available
North Atlantic oceanic and atmospheric variability is central in determining the behavior of surface climate and hence the occurrence of extremes over the Northern Hemisphere, which in turn have huge impacts on societies, economies and environment. The aim of this study is to gain further insight on the evolution of SST and atmospheric circulation...
Article
Full-text available
In March 2019, German-speaking scientists and scholars calling themselves Scientists for Future, published a statement in support of the youth protesters in Germany, Austria, and Switzerland (Fridays for Future, Klimastreik/Climate Strike), verifying the scientific evidence that the youth protestors refer to. In this article, they provide the full...
Preprint
The future response of the Antarctic ice sheets to rising temperatures remains highly uncertain. A valuable analogue for assessing the sensitivity of Antarctica to warming is the Last Interglacial (129-116 kyr), when global sea level peaked 6 to 9 meters above present. Here we report a blue-ice record of ice-sheet and environmental change from the...
Article
Full-text available
This work reviews the literature on an alleged global warming 'pause' in global mean surface temperature (GMST) to determine how it has been defined, what time intervals are used to characterise it, what data are used to measure it, and what methods used to assess it. We test for 'pauses', both in the normally understood meaning of the term to mean...
Article
Full-text available
We review the evidence for a putative early 21st-century divergence between global mean surface temperature (GMST) and Coupled Model Intercomparison Project Phase 5 (CMIP5) projections. We provide a systematic comparison between temperatures and projections using historical versions of GMST products and historical versions of model projections that...
Preprint
The summer of 2018 witnessed a number of extreme weather events such as heatwaves in North America, Western Europe and the Caspian Sea region and rainfall extremes in South-East Europe and Japan that occurred near-simultaneously. Here we show that these extremes were connected by an amplified hemisphere-wide wavenumber 7 circulation pattern. We sho...
Article
Full-text available
Persistent episodes of extreme weather in the Northern Hemisphere summer have been associated with high-amplitude quasi-stationary atmospheric Rossby waves, with zonal wave numbers 6 to 8 resulting from the phenomenon of quasi-resonant amplification (QRA). A fingerprint for the occurrence of QRA can be defined in terms of the zonally averaged surfa...
Article
Full-text available
The Atlantic meridional overturning circulation (AMOC)-a system of ocean currents in the North Atlantic-has a major impact on climate, yet its evolution during the industrial era is poorly known owing to a lack of direct current measurements. Here we provide evidence for a weakening of the AMOC by about 3 ± 1 sverdrups (around 15 per cent) since th...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Book
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Chapter
Der Klimawandel ist – nicht zuletzt nach der einzigartigen Serie verheerender Wetterextreme der letzten Jahre – in aller Munde. Angesichts seiner einschneidenden Bedeutung für Natur und Zivilisation ist das kein Wunder. Doch was ist eigentlich unter Klimawandel zu verstehen, und welche Faktoren sind für das Klima verantwortlich? Zwei international...
Article
Full-text available
Although the 2015 Paris Agreement seeks to hold global average temperature to 'well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 °C above pre-industrial levels', projections of global mean sea-level (GMSL) rise commonly focus on scenarios in which there is a high probability that warming exce...
Conference Paper
North Atlantic SST variability results from the interaction of atmospheric and oceanic processes. The North Atlantic Oscillation (NAO) drives changes in SST patterns but is also driven by them on certain time-scales. These interactions are not very well understood and might be affected by anthropogenic climate change. Paleo reconstructions indicate...
Article
Full-text available
Several recent northern hemisphere summer extremes have been linked to persistent high-amplitude wave patterns (e.g. heat waves in Europe 2003, Russia 2010 and in the US 2011, Floods in Pakistan 2010 and Europe 2013). Recently quasi-resonant amplification (QRA) was proposed as a mechanism that, when certain dynamical conditions are fulfilled, can l...
Article
We use a previously developed semi-empirical approach to assess the likelihood of the sequence of consecutive record-breaking temperatures in 2014, 2015, and 2016. This approach combines information from historical temperature data and state-of-the-art historical climate model simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP...
Article
Christiana Figueres and colleagues set out a six-point plan for turning the tide of the world’s carbon dioxide by 2020.
Article
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Scientific Reports 7 : Article number: 45242; 10.1038/srep45242 published online: 27 March 2017 ; updated: 26 May 2017 . This Article contains an error in Figure 1a, where the y-axis ‘Temperature (K)’ is incorrectly labelled as ‘Temperature (°C)’.
Article
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Global surface temperatures continue to rise. In most surface temperature data sets, the years 2014, 2015 and again 2016 set new global heat records since the start of regular measurements. Never before have three record years occurred in a row. We show that this recent streak of record heat does not in itself provide statistical evidence for an ac...
Article
Slow-moving planetary waves of high amplitudes are often associated with persistent surface weather conditions. This persistence can lead to extreme weather events with potentially serious implications for society and nature. Quasi-resonant amplification of planetary waves (QRA) has been proposed as a mechanism to generate high-amplitude hemisphere...
Article
Full-text available
Persistent episodes of extreme weather in the Northern Hemisphere summer have been shown to be associated with the presence of high-amplitude quasi-stationary atmospheric Rossby waves within a particular wavelength range (zonal wavenumber 6?8). The underlying mechanistic relationship involves the phenomenon of quasi-resonant amplification (QRA) of...
Article
The Paris Agreement duly reflects the latest scientific understanding of systemic global warming risks. Limiting the anthropogenic temperature anomaly to 1.5–2 °C is possible, yet requires transformational change across the board of modernity.
Article
Full-text available
In boreal spring-to-autumn (May-to-September) 2012 and 2013, the Northern Hemisphere (NH) has experienced a large number of severe midlatitude regional weather extremes. Here we show that a considerable part of these extremes were accompanied by highly magnified quasistationary midlatitude planetary waves with zonal wave numbers m = 6, 7, and 8. We...
Article
Full-text available
In May 2014, the Balkans were hit by a Vb-type cyclone that brought disastrous flooding and severe damage to Bosnia and Herzegovina, Serbia, and Croatia. Vb cyclones migrate from the Mediterranean, where they absorb warm and moist air, to the north, often causing flooding in central/eastern Europe. Extreme rainfall events are increasing on a global...
Article
Full-text available
We assess the relationship between temperature and global sea-level (GSL) variability over the Common Era through a statistical metaanalysis of proxy relative sea-level reconstructions and tide-gauge data. GSL rose at 0.1 ± 0.1 mm/y (2σ) over 0-700 CE. A GSL fall of 0.2 ± 0.2 mm/y over 1000-1400 CE is associated with ∼0.2 °C global mean cooling. A...
Article
Full-text available
2014 was nominally the warmest year on record for both the globe and northern hemisphere based on historical records spanning the past one and a half centuries1,2. It was the latest in a recent run of record temperatures spanning the past decade and a half. Press accounts reported odds as low as one-in-650 million that the observed run of global te...
Chapter
The thermohaline circulation (THC) is that part of the ocean circulation which is driven by fluxes of heat and freshwater across the sea surface and subsequent interior mixing of heat and salt. The term thus refers to a driving mechanism. Important features of the THC are deep water formation, spreading of deep waters partly through deep boundary c...
Article
Full-text available
Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change. Maps of temperature trends over the twentieth century show a conspicuous region of cooling in the northern Atlantic. Here we present multiple lines of evidence suggesting that this cooling may be due to a reduc...
Article
Persistent episodes of extreme weather in the Northern Hemisphere summer have been associated with high-amplitude quasi-stationary atmospheric Rossby waves, with zonal wave numbers 6 to 8 resulting from the phenomenon of quasi-resonant amplification (QRA). A fingerprint for the occurrence of QRA can be defined in terms of the zonally averaged surfa...
Article
Full-text available
We aim to address the question of whether or not there is a significant recent ‘hiatus’, ‘pause’ or ‘slowdown’ of global temperature rise. Using a statistical technique known as change point (CP) analysis we identify the changes in four global temperature records and estimate the rates of temperature rise before and after these changes occur. For e...
Article
Full-text available
Interdisciplinary studies of geologic archives have ushered in a new era of deciphering magnitudes, rates, and sources of sea-level rise from polar ice-sheet loss during past warm periods. Accounting for glacial isostatic processes helps to reconcile spatial variability in peak sea level during marine isotope stages 5e and 11, when the global mean...
Article
Full-text available
Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change. Maps of temperature trends over the twentieth century show a conspicuous region of cooling in the northern Atlantic. Here we present multiple lines of evidence suggesting that this cooling may be due to a reduc...
Article
Full-text available
The recent decade has seen an exceptional number of high-impact summer extremes in the Northern Hemisphere midlatitudes. Many of these events were associated with anomalous jet stream circulation patterns characterized by persistent high-amplitude quasi-stationary Rossby waves. Two mechanisms have recently been proposed that could provoke such patt...
Conference Paper
The Eurasian Arctic contains some of the largest rivers on Earth. Our synthesis of river monitoring data reveals that the average annual discharge of freshwater from the six largest Eurasian rivers (Yenisey, Lena, Ob', Kolyma, Pechora, S. Dvina) to the Arctic Ocean increased about 7% from 1936 through 1999. Correspondence between discharge from the...