News — Potsdam Institute for Climate Impact Research

More than 500 million people might face increasing water scarcity

10/08/2013 - Both freshwater availability for many millions of people and the stability of ecosystems such as the Siberian tundra or Indian grasslands are put at risk by climate change. Even if global warming is limited to 2 degrees above pre-industrial levels, 500 million people could be subject to increased water scarcity – while this number would grow by a further 50 percent if greenhouse-gas emissions are not cut soon. At 5 degrees global warming almost all ice-free land might be affected by ecosystem change. This is shown by complementary studies now published by scientists of the Potsdam Institute for Climate Impact Research (PIK).

Extreme events forcing global warming? Climate extremes and the carbon cycle

08/15/2013 – Extreme events like heat waves, droughts, heavy rain might not only occur more frequently due to climate change. They could also force global warming if terrestrial ecosystems release CO2 as a result of those extremes. An international team of researchers now analyzed the impacts of extremes on forests, bogs, grass landscapes and arable areas througout the world, among them scientists from the Potsdam Institute for Climate Impact Research (PIK). Terrestrial ecosystems absorb about 11 billion tons less carbon dioxide every year as the result of the extreme climate events than they could if the events did not occur, the researchers write in the renowned journal Nature. This is equivalent to approximately a third of global CO2 emissions per year.

Multifold increase in heat extremes by 2040

08/15/2013 - Extremes such as the severe heat wave last year in the US or the one 2010 in Russia are likely to be seen much more often in the near future. A few decades ago, they were practically absent. Today, due to man-made climate change monthly heat extremes in summer are already observed on 5 percent of the land area. This is projected to double by 2020 and quadruple by 2040, according to a study by scientists of the Potsdam Institute for Climate Impact Research (PIK) and the Universidad Complutense de Madrid (UCM). A further increase of heat extremes in the second half of our century could be stopped if global greenhouse-gas emissions would be reduced substantially.

Carbon Dioxide Removal: Assessing potentials - and risks

06/24/2013 - With global greenhouse-gas emissions continuing to rise and a possibility that international cooperation in climate policy will continue to be delayed, a number of large-scale technical approaches have been suggested to counter strong climate change. Direct carbon dioxide removal (CDR) from the atmosphere is a measure that two groups of scientists at the Potsdam Institute for Climate Impacts Research (PIK) are now looking into. Theoretically, it could make ambitious mitigation economically more feasible, increase the likelihood of achieving the 2-degrees warming threshold agreed by the international community, or lower atmospheric carbon dioxide concentrations in the future to partially compensate for lack of mitigation today. The PIK projects are part of a programme financed by Deutsche Forschungs-Gemeinschaft on climate engineering that is starting this month.

Floods in the light of climate change

06/21/2013 - The nationwide floods have been keeping the country´s attention for some time now. This week, the Minister for the Environment, Peter Altmaier, visited flooded regions near Dessau/Bitterfeld. He was accompanied by Friedrich-Wilhelm Gerstengarbe of the Potsdam Institute for Climate Impact Research (PIK), who briefed him on the relation between climate change and extreme weather events, as well as a number of other high-ranking experts. In the previous weeks, Gerstengarbe and other PIK scientists have given several interviews on the subject, mainly on the question if climate change is one of the causes for the floods.

Research on Antarctica awarded with prize for upcoming scientists

05/03/2013 - For her research on climate change and the Antarctic ice shield, Ricarda Winkelmann was awarded with a young scientists prize. The Natural Sciences Department at the University of Potsdam presents this prize for outstanding publications. Winkelmann, aged 27, leads the group on projections of Antarctica´s contribution to future global sea level rise at the Potsdam Institute for Climate Impact Research. The jury highlighted her "most impressive contribution to our understanding of the physics of Antarctica's ice shield dynamics."

A cold March despite of climate change

03/28/2013 - March 2013 in Europe has been somewhat cold. How this might be linked to global warming was shown by a study by PIK scientist Vladimir Petoukhov in 2010 already. The shrinking of sea-ice in the eastern Arctic causes some regional heating of the lower levels of air – which may lead to strong anomalies in atmospheric airstreams, triggering an overall cooling of the northern continents. These anomalies could increase the probability of cold winter extremes in Europe and northern Asia, the analysis showed.

Permafrost soil thawing accelerates climate change despite more abundant vegetation

2013/03/13 - Global warming affects permafrost soils, for instance in Siberia, in two opposing ways. Their thawing accelerates decomposition processes in the soil, leading to higher CO2 emissions. On the other hand, enhanced vegetation growth due to higher temperatures leads to carbon intake by the plants, and consequently storage in the soil. However, the – often neglected – second effect in the long run cannot counter the first one, reveals a study now published by scientists of the Potsdam Institute for Climate Impact Research.

Naturkundemuseum and PIK link history and future

03/08/2013 - Naturkundemuseum Berlin, Germany´s leading natural history museum, and the Potsdam Institute for Climate Impact Research have agreed to work closer together at a meeting in early March. When a delegation from the museum, led by its Director-General Prof. Dr. Johannes Vogel, visited PIK, a number of ideas for a closer cooperation were identified.

Weather extremes provoked by trapping of giant waves in the atmosphere

02/25/2013 - The world has suffered from severe regional weather extremes in recent years, such as the heat wave in the United States in 2011 or the one in Russia 2010 coinciding with the unprecedented Pakistan flood. Behind these devastating individual events there is a common physical cause, propose scientists of the Potsdam Institute for Climate Impact Research (PIK). The study will be published this week in the US Proceedings of the National Academy of Sciences and suggests that man-made climate change repeatedly disturbs the patterns of atmospheric flow around the globe's Northern hemisphere through a subtle resonance mechanism.

Global warming has increased monthly heat records by a factor of five

01/14/2013 - Monthly temperature extremes have become much more frequent, as measurements from around the world indicate. On average, there are now five times as many record-breaking hot months worldwide than could be expected without long-term global warming, shows a study now published in Climatic Change. In parts of Europe, Africa and southern Asia the number of monthly records has increased even by a factor of ten. 80 percent of observed monthly records would not have occurred without human influence on climate, concludes the authors-team of the Potsdam Institute for Climate Impact Research (PIK) and the Complutense University of Madrid.

Why early Earth was no snowball: Illuminating the ”faint young Sun paradox”

12/17/2012 - In the early history of planet Earth, the Sun was up to 25 per cent less luminous than today. Yet there is strong evidence that the Earth’s oceanic surface was not completely frozen. High concentrations of warming greenhouse gases like carbon dioxide (CO2) seem to be the most obvious solution to this famous “faint young Sun paradox”. A team of scientists from the Potsdam Institute for Climate Impact Research (PIK) analyzed in computer simulations how much CO2 in the atmosphere was necessary to prevent the early Earth from falling into a “snowball state”. They found the critical amount to be significantly higher than previously assumed, according to their study now published in Geophysical Research Letters. This sheds light on the environment on early Earth during a time when life first appeared on our planet.

Projected sea-level rise may be underestimated

11/28/2012 - The rate of sea-level rise in the past decades is greater than projected by the latest assessments of the IPCC, while global temperature increases in good agreement with its best estimates. This is shown by a study now published in the journal Environmental Research Letters. Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research (PIK) and his colleagues compare climate projections to actual observations from 1990 up to 2011. That sea level is rising faster than expected could mean that the Intergovernmental Panel on Climate Change’s (IPCC) sea-level rise projections for the future may be biased low as well, their results suggest.

„Clouds, wind and weather“ is green book of the year

09/26/2012 - For its “lasting impact on ecological awareness in Germany”, PIK-scientist Stefan Rahmstorf´s children´s book “Clouds, wind and weather“ was elected green book of the year 2012 last night. The price is awarded by the German Environment Foundation and the editorial team of “Jahrbuch Ökologie”.