Nobel Laureates across the world and across disciplines this week are gathering in Hong Kong to elevate the debate on climate change to a new level and to feed into the world climate summit in Paris later this year. For the first time, the Nobel Laureates are meeting in Asia for the symposium, “4C: Changing Climate, Changing Cities”. Cities are key to addressing the challenge of climate change which, if unabated, might result in a 4°C rise in mean temperature by the end of this century. Participants of the symposium include Nobel Prize winners Yuan T. Lee (Chemistry, 1986) from Taiwan, Brian Schmidt (Physics, 2011) from Australia, and James A. Mirrlees from the United Kingdom (Economics, 2006), complemented by international renowned experts such as K.S. Wong, Secretary for the Environment, The Government of the Hong Kong Special Administrative Region, and Aromar Revi of the Indian Institute for Human Settlements.
Climate change in Antarctica: Natural temperature variability underestimated - Cold spell superimposes man-made warming
04/16/2015 - The Antarctic ice sheet is one of the tipping elements in the climate system and hence of vital importance for our planet’s future under man-made climate change. Even a partial melting of the enormous ice masses of Antarctica would raise sea-levels substantially. Therefore it is of utmost importance to provide sound knowledge on the extent of anthropogenic warming of the ice-covered continent. A new analysis by German physicists shows that the uncertainties in the temperature trends over Antarctica are larger than previously estimated. “So far it seemed there were hardly any major natural temperature fluctuations in Antarctica, so almost every rise in temperature was attributed to human influence,” says Armin Bunde of Justus-Liebig-Universität Gießen (JLU). “Global warming as a result of our greenhouse gas emissions from burning fossil fuels is a fact. However, the human influence on the warming of West Antarctica is much smaller than previously thought. The warming of East Antarctica up to now can even be explained by natural variability alone.” The results of their study are now published in the journal Climate Dynamics.
03/24/2015 - The senate of the Leibniz Association - an organisation uniting more than 80 scientific institutions - issued a statement on Monday which brings the evaluation of PIK to a successful conclusion. The research results of the institute as a whole were rated “outstanding”. The rating is based on a review carried out by a team of top international researchers, which takes place only once every seven years. The reviewers judged that PIK has developed into a globally leading institute for climate science. As well as its achievements in research, the institute's important role in scientific policy advice was praised.
03/24/2015 - The Atlantic overturning is one of Earth’s most important heat transport systems, pumping warm water northwards and cold water southwards. Also known as the Gulf Stream system, it is responsible for the mild climate in northwestern Europe. Scientists now found evidence for a slowdown of the overturning – multiple lines of observation suggest that in recent decades, the current system has been weaker than ever before in the last century, or even in the last millennium. The gradual but accelerating melting of the Greenland ice-sheet, caused by man-made global warming, is a possible major contributor to the slowdown. Further weakening could impact marine ecosystems and sea level as well as weather systems in the US and Europe.
03/19/2015 - The current El Niño event has been predicted by an international team of scientists more than one year ago – earlier than ever before. This breakthrough in forecasting the most important phenomenon of natural climate variability has been enabled by novel approach of complex networks analysis of atmospheric temperature data from the Pacific. Such forecast can help farmers in Brazil, Australia or India to prepare and for instance seed the right crops. In an unusual move, the scientists had published their unprecedented early warning early on – fully aware of the reputational risks.
03/17/2015 - Although it sounds paradoxical, rising temperatures might result in more snowfall in Antarctica. Each degree of regional warming could increase snowfall on the ice continent by about 5 percent, an international team of scientists led by the Potsdam Institute for Climate Impact Research now quantified. Published in the journal Nature Climate Change, their work builds on high-quality ice-core data and fundamental laws of physics captured in global and regional climate model simulations. The results provide a missing link for future projections of Antarctica’s critical contribution to sea-level rise. However, the increase in snowfall will not save Antarctica from losing ice, since a lot of the added ice is transported out into the ocean by its own weight.
03/12/2015 - Storm activity in large parts of the US, Europe and Russia significantly calmed down during summers over the past decades, but this is no good news. The weakening of strong winds associated with the jetstream and weather systems prolongs and hence intensifies heat extremes like the one in Russia in 2010 which caused devastating crop failures and wildfires. This is shown in a study to be published in the renowned journal Science by a team of researchers from the Potsdam Institute for Climate Impact Research. They link the findings to changes in the Arctic caused by man-made global warming.
02/02/2015 - Clean technology support can to some extent make up for weak CO2 pricing and hence help keep the two degrees target within reach, a new study shows. Even if the world climate summit in Paris later this year is successful in striking a climate deal, it might not bring about sharp greenhouse-gas cuts in the near-term. However, emission targets could be strengthened by complementary policies, such as support for renewables, a ban on new coal-fired power plants, and an initially modest global minimum price on CO2. If such a policy package – each component of which has already been enacted in some countries – were to be put into practice globally now, this could also pave the way for a clean economy with faster long-term CO2 reductions after 2030.
01/16/2015 - Four of nine planetary boundaries have now been crossed as a result of human activity, says an international team of 18 researchers in the journal Science. The four are: climate change, loss of biosphere integrity, land-system change, altered biogeochemical cycles. The scientists say that two of these, climate change and biosphere integrity, are “core boundaries” – significantly altering either of these would “drive the Earth System into a new state”. The team will present their findings in seven seminars at the World Economic Forum in Davos (21-25 January).
12/19/2014 - Around the globe, forests are found to be undergoing strong changes due to human influence already today. Degradation of woods due to man-made climate change cannot be ruled out for the future, a Special Feature to be published next week in the Journal of Ecology, led by a team of scientists of the Potsdam Institute for Climate Impact Research (PIK), now shows. To understand and improve the resilience of forests, a combination of approaches from small-scale field experiments to large-scale computer simulations can help, according to the studies. Taking a risk perspective, the scientists caution that global warming puts additional pressure on some of the most valuable ecosystems on Earth.
Currently proposed climate policy pledges are an important step forward but fall short of 2 degrees Celsius
12/15/2014 - Pledges to reduce emissions in China, Europe and the US provide an important step forward for climate change action, but a more comprehensive effort is needed to stabilize the climate below critical thresholds. Climate finance can cover investment gaps and alleviate distributional tensions, a new study shows. The study looks into several key negotiation issues on the road from the climate summit in Lima to the one in Paris 2015.
11/23/2014 - Weather extremes such as heat waves that up to now were highly unusual are likely to become the new normal, according to a report by the Potsdam Institute for Climate Impact Research (PIK) now launched by the World Bank. Climate Change impacts are already being felt today and will grow even if warming is limited below 2 degrees. However, with unabated warming of probably 4 degrees within our century, the consequences increase drastically. The report is the third in a series, entitled “Turn down the heat” by the World Bank – now focused on how climate impacts and social vulnerability interact, or how the poor are hit hardest in Latin America and the Caribbean, Middle East and North Africa, and East and Central Asia.
11/17/2014 - Global forest conservation measures meant to mitigate climate change are likely to drive massive cropland expansion into shrublands or savannahs to satisfy the ever-growing hunger for arable land. The consequent changes in land use could cause substantial greenhouse gas emissions, a new study in the journal Nature Climate Change shows. In contrast to previous assumptions, conservation schemes that focus only on forests may thus fail to significantly reduce CO2 emissions from land-use change. If ecosystem protection policies aim at climate protection, they need to cover the whole range of land types, according to comprehensive computer simulations. To compensate for such restrictions on land use, intensification of agriculture to generate higher yields is important.
11/04/2014 - Reducing emissions of non-CO2 gases and air pollutants with climate effects would bring health benefits and near-term climate co-benefits - but the impact on long-term climate change might be lower than previously estimated, according to a new study of the potential of air pollution and carbon dioxide mitigation in climate stabilization scenarios.
11/02/2014 - The Intergovernmental Panel on Climate Change (IPCC) completed its Fifth Assessment Report on Sunday in Copenhagen. Ottmar Edenhofer, Co-Chair of the IPCC Working Group III ‘Mitigation of Climate Change’, and one of the authors of the now released Synthesis Report, points to the contrast between the potentially irreversible impacts of unmitigated climate change and the manageable costs of ambitious mitigation.
10/15/2014 - The recent natural gas boom due to the use of technologies such as fracking will not lead to a reduction of overall greenhouse gas emissions. Burning natural gas produces only half the CO2 emissions as coal per unit of energy. However, as natural gas becomes abundant and therefore cheap, it adds to the total energy supply and only partially replaces coal, a study published in the journal Nature shows. This market effect erases the advantage of lower emissions from the natural gas itself, according to an unprecedented international comparison of computer simulations.
10/14/2014 - Predicting floods following extreme rainfall in the central Andes is enabled by a new method. Climate change has made these events more frequent and more severe in recent decades. Now complex networks analysis of satellite weather data makes it possible to produce a robust warning system for the first time, a study to be published in the journal Nature Communications shows. This might allow for improved disaster preparedness. As the complex systems technique builds upon a mathematical comparison that can be utilised for any time series data, the approach could be applied to extreme events in all sorts of complex systems.
Dead ends and solutions for the climate crisis: Panel discussion with Environment Minister Barbara Hendricks
09/01/2014 – Dr. Barbara Hendricks, Federal Minister for the Environment, Nature Conservation, Building and Nuclear Safety, Dr. Michael Otto, Chairman of the Otto Group Supervisory Board and Chairman of the Board of Trustees of the Michael Otto Foundation for Environmental Protection, Prof. Dr. Christian Thomsen, President of the Technische Universität Berlin, Prof. Dr. Ottmar Edenhofer, chief economist at the Potsdam Institute for Climate Impact Research and Professor for Climate Economics at the Technische Universität Berlin and Jennifer Morgan of the World Resources Institute in Washington D.C. will discuss "Climate change and climate mitigation between global transformation and national challenges" in Hamburg on September 2, with topics ranging from Germany's energy transition to the European Union's emissions trading.
8/14/2014 - Ice discharge from Antarctica could contribute up to 37 centimeters to the global sea level rise within this century, a new study shows. For the first time, an international team of scientists provide a comprehensive estimate on the full range of Antarctica’s potential contribution to global sea level rise based on physical computer simulations. Led by the Potsdam Institute for Climate Impact Research, the study combines a whole set of state-of-the-art climate models and observational data with various ice models. The results reproduce Antarctica’s recent contribution to sea level rise as observed by satellites in the last two decades and show that the ice continent could become the largest contributor to sea level rise much sooner than previously thought.
08/12/2014 - Weather extremes in the summer - such as the record heat wave in the United States that hit corn farmers and worsened wildfires in 2012 - have reached an exceptional number in the last ten years. Man-made global warming can explain a gradual increase in periods of severe heat, but the observed change in the magnitude and duration of some events is not so easily explained. It has been linked to a recently discovered mechanism: the trapping of giant waves in the atmosphere. A new data analysis now shows that such wave-trapping events are indeed on the rise.
06/26/2014 - Technologies that are discussed controversially today may be needed to keep the future risks and costs of climate change in check. Combining the production of energy from fossil fuels and biomass with capturing and storing the CO2 they emit (CCS) can be key to achieving current climate policy objectives such as limiting the rise of the global mean temperature to below 2 degrees Celsius. This is shown by the most comprehensive study to date on technology strategies to combat climate change, published in a special issue of the journal Climatic Change. It is based on the analysis of 18 computer models by an international team of scientists under the roof of the Stanford Energy Modelling Forum (EMF 27).